Major psychiatric disorders associated with shorter telomeres, indicative of cellular ageing
3-4 cups linked to longer telomeres, equal to 5 extra ‘biological’ years, say researchers
But no such effects observed beyond this daily amount

Drinking a maximum of 3-4 cups of coffee a day may slow the ‘biological’ ageing of people with severe mental illness, by lengthening their telomeres—indicators of cellular ageing—and giving them the equivalent of 5 extra biological years, compared with non-coffee drinkers, finds research published in the open access journal BMJ Mental Health.

But no such effects were observed beyond this quota, which is the maximum daily intake recommended by several international health authorities, including the NHS and the US Food and Drug Administration.

Telomeres sit on the end of chromosomes and perform a role similar to the plastic tips on the end of shoelaces.  While telomere shortening is a natural part of the ageing process, it seems to be accelerated in those with major psychiatric disorders, such as psychosis, schizophrenia, and bipolar disorder, note the researchers.

Telomeres are sensitive to environmental factors, including, possibly, diet. And coffee, when drunk in moderation, has been associated with various health benefits, prompting the researchers to explore whether it might influence the rate at which telomeres shorten in people with major mental ill health.

They included 436 adult participants from the Norwegian Thematically Organised Psychosis (TOP) study, recruited between 2007 and 2018: 259 had schizophrenia; the rest (177) had affective disorders, including bipolar disorder and major depressive disorder with psychosis.

Participants were asked how much coffee they drank every day and were grouped into 4 categories: zero (44); 1–2 cups; 3–4 cups (110); and 5 or more cups. And they were asked whether they smoked, and if so, for how long they had done so.

Participants who drank 5+ cups a day were significantly older than those who drank none or 1–2 cups a day. And those with schizophrenia drank significantly more coffee than those with an affective disorder.

Smoking is associated with faster caffeine metabolism. And around three quarters of participants (77%; 337) smoked, and had done so, on average, for 9 years. And those drinking 5+ cups a day had smoked for significantly longer than any of the other groups.

Telomere length was measured from white blood cells (leucocytes) extracted from blood samples, and this revealed a significant difference among the 4 groups, forming a J shaped curve.

Compared with those drinking no coffee, drinking up to 3–4 cups a day was associated with longer telomeres, but not in those participants drinking 5 or more every day.

Those participants getting a daily 4-cup caffeine hit had telomere lengths comparable to a biological age 5 years younger than that of non-coffee drinkers after adjusting for age, sex, ethnicity, tobacco use, type of mental ill health, and drug treatment.

This is an observational study, and, as such, no firm conclusions can be drawn about cause and effect. And the researchers acknowledge that they had no information on potentially influential factors, including the type and timing of the coffee consumed, actual caffeine levels, or other sources of caffeinated drinks.

But there are plausible biological explanations for their findings, they suggest. These include the powerful antioxidant and anti-inflammatory compounds found in coffee.

“Telomeres are highly sensitive to both oxidative stress and inflammation, further highlighting how coffee intake could help preserve cellular ageing in a population whose pathophysiology may be predisposing them to an accelerated rate of ageing,” they explain.

Coffee is popular worldwide, with an estimated 10.56 billion kilos consumed around the globe in 2021-2 alone, they point out.

But despite its potential benefits, “consuming more than the daily recommended amount of coffee may also cause cellular damage and [telomere] shortening through the formation of reactive oxygen species,” they caution, emphasising that international health authorities recommend limiting caffeine intake to a maximum of 400 mg/day (4 cups of coffee).

Notes for editors
Research: Coffee intake is associated with telomere length in severe mental disorders Doi: 10.1136/bmjment-2025-301700
Journal: BMJ Mental Health

External funding: Medical Research Council; Research Council of Norway

Link to Academy of Medical Sciences press release labelling system http://press.psprings.co.uk/AMSlabels.pdf

Externally peer reviewed? Yes
Evidence type: Observational
Subjects: People

The post Daily coffee drinking may slow biological ageing of people with major mental illness first appeared on BMJ Group.

Increasing from twice as high for one disorder to 11 times as high for four or more
In particular, concurrent mood + anxiety disorder linked to odds of up to 90% for dementia

The odds of developing dementia are strongly linked to the number of co-existing mental health disorders, rising from twice as high for one disorder to 11 times as high for four or more, finds research published in the open access journal BMJ Mental Health.

In particular, the combination of concurrent mood and anxiety disorders is linked to odds of  dementia of up to 90%, the findings indicate.

Psychiatric disorders, such as depression, anxiety, and bipolar disorder, have been individually associated with an increased risk of dementia. But the existing body of research hasn’t assessed the impact of multiple co-existing psychiatric disorders, say the researchers.

In a bid to plug this knowledge gap, they drew on information extracted from the clinical database of the psychiatry department of Bicêtre Hospital, Paris.

They included 3688 patients aged at least 45 and diagnosed with one or more of the most common psychiatric disorders—depression, anxiety, psychosis, substance misuse, personality disorder and bipolar disorder—between August 2009 and October 2023. And they included every type of dementia and cognitive impairment.

The average age of the entire group  was 67: 70 in those with dementia, and 66 in those without. And the average delay between diagnosis of the first psychiatric disorder and dementia diagnosis was 18 months, but ranged from 7 to 13 years.

Nearly 71% (2608) of the patients had one psychiatric disorder; 21.5% (789) had two; 6% (226) had three; and 2% (65) had four or more.

After adjusting for age, sex, and cardiovascular risk factors, the odds of dementia rose in tandem with the number of psychiatric disorders.

Compared with those with one psychiatric disorder, those with two, were twice as likely to be diagnosed with dementia, while those with three, were more than 4 times as likely to do so.

And those with four or more, were 11 times as likely to have dementia.

In particular, the combination of concurrent mood and anxiety disorders was linked to odds of dementia of up to 90%.

The effect of concurrent psychiatric disorders seems to be specific to dementia and suggests they may be early warning signs of it, because further in-depth analysis testing the potential effects on the likelihood of other disease—in this case renal failure–failed to show any link, note the researchers.

This is an observational study, and as such, no firm conclusions can be drawn about cause and effect. And the researchers caution that dementia diagnoses may have been delayed, and, without clinical confirmation, misclassification may have occurred.

All the study participants were also drawn from just one psychiatric department, so may not be representative of all patients with mental health disorders, added to which, information on several potentially influential factors, including socioeconomic status, family history, duration of psychiatric disorder, treatment and brain scans, wasn’t available, the researchers add.

Nevertheless, they conclude:“The findings of this study highlight the strong association between the co-occurrence of psychiatric disorders and an increased posterior probability of developing dementia, particularly for patterns with anxiety and mood disorders.

“Recent advancements in dementia diagnoses, such as the development of biomarkers in blood and cerebrospinal fluid, as well as the use of positron emission tomography, encourage earlier and more accurate detection of dementia.

“Integrating these tools into clinical practice for high-risk individuals, especially those with specific psychiatric comorbidities identified in this study, could significantly enhance their care management, given the recent advancements in dementia treatment.”

09/09/2025

Notes for editors
Research: Strong association between psychiatric disorders co-occurrence and dementia: a Bayesian approach on a 14-year clinical data warehouse  Doi:10.1136/bmjment-2025- 301651
Journal: BMJ Mental Health

Link to Academy of Medical Sciences press release labelling system http://press.psprings.co.uk/AMSlabels.pdf

Externally peer reviewed? Yes
Evidence type: Observational
Subjects: People

The post Odds of dementia strongly linked to number of co-existing mental health disorders first appeared on BMJ Group.

The post ‘Solastalgia’ might help explain effects of climate change on mental health first appeared on BMJ Group.

Risks higher in women than in men with the same condition
Chronic exposure to systemic inflammation may explain associations, say researchers

Living with an autoimmune disease is linked to a near doubling in the risk of persistent mental health issues, such as depression, generalised anxiety, and bipolar disorder, with these risks higher in women than in men, finds a large population-based UK study, published in the open access journal BMJ Mental Health.

Chronic exposure to the systemic inflammation caused by the autoimmune disease may explain the associations found, say the researchers.

A growing body of evidence suggests that inflammation is linked to mental ill health, but many of the published studies have relied on small sample sizes, limiting their statistical power, note the researchers.

In a bid to overcome this, they drew on data from 1.5 million participants in the recently established Our Future Health dataset from across the UK. Participants’ average age was 53; just over half (57%) were women; and 90% identified as White.

On recruitment to Our Future Health, participants completed a baseline questionnaire to provide personal, social, demographic, health and lifestyle information.

Health information included lifetime diagnoses–including for their biological parents–for a wide range of disorders, including autoimmune and psychiatric conditions.

Six autoimmune conditions were included in the study: rheumatoid arthritis; Graves’ syndrome (thyroid hormone disorder); inflammatory bowel disease; lupus, multiple sclerosis; and psoriasis.

The mental health conditions of interest were self-reported diagnoses of affective disorders, defined as depression, bipolar, or anxiety disorder.

In all, 37,808 participants reported autoimmune conditions and 1,525,347 didn’t. Those with autoimmune conditions were more likely to be women (74.5% vs 56.5%) and more likely to report lifetime diagnoses of affective disorders for their biological parents:  8% vs 5.5% for fathers; 15.5% vs 11% for mothers.

Chronic and pathogenic immune system activation—including the presence of markers of inflammation—is a hallmark of many autoimmune conditions. And in the absence of direct measurements of inflammatory biomarkers, an autoimmune condition was regarded as a proxy for chronic inflammation in this study.

The lifetime prevalence of any diagnosed affective disorder was significantly higher among people with an autoimmune disorder than it was among the general population: 29% vs 18%.

Similar associations in lifetime prevalence emerged for depression and anxiety: 25.5% vs just over 15% for depression; and just over 21% vs 12.5% for anxiety.

While the overall prevalence of bipolar disorder was much lower, it was still significantly higher among those with an autoimmune disorder than it was among the general population:  just under 1% compared with 0.5%.

The prevalence of current depression and anxiety was also higher among people with autoimmune conditions.

And the prevalence of affective disorders was significantly and consistently higher among women than it was among men with the same physical health conditions: 32% compared to 21% among participants with any autoimmune disorder.

The reasons for this aren’t clear, say the researchers, but “theories suggest that sex hormones, chromosomal factors, and differences in circulating antibodies may partly explain these sex differences,” they write.

“Women (but not men) with depression exhibit increased concentrations of circulating cytokines and acute phase reactants compared with non-depressed counterparts. It is therefore possible that women may experience the compounding challenges of increased occurrence of autoimmunity and stronger effects of immune responses on mental health, resulting in the substantially higher prevalence of affective disorders observed in this study,” they add.

Overall, the risk for each of the affective disorders was nearly twice as high—87-97% higher—in people with autoimmune conditions, and remained high even after adjusting for potentially influential factors, including age, household income, and parental psychiatric history.

No information was available on the time or duration of illness, making it impossible to determine whether autoimmune conditions preceded, co-occurred with, or followed, affective disorders, note the researchers.

No direct measurements of inflammation were made either, and it was therefore impossible to establish the presence, nature, timing or severity of inflammation, they add.

“Although the observational design of this study does not allow for direct inference of causal mechanisms, this analysis of a large national dataset suggests that chronic exposure to systemic inflammation may be linked to a greater risk for affective disorder,” they conclude.

“Future studies should seek to determine whether putative biological, psychological, and social factors—for example, chronic pain, fatigue, sleep or circadian disruptions and social isolation—may represent potentially modifiable mechanisms linking autoimmune conditions and affective disorders.”

And they suggest that it may be worth regularly screening people diagnosed with autoimmune disease for mental health conditions, especially women, to provide them with tailored treatment early on.

25/06/2025

Notes for editors
Research: Affective disorders and chronic inflammatory conditions: analysis of 1.5 million participants in Our Future Health Doi: 10.1136/bmjment-2025-301706
Journal: BMJ Mental Health

External funding: UK Medical Research Council

Link to Academy of Medical Sciences press release labelling system
http://press.psprings.co.uk/AMSlabels.pdf

Externally peer reviewed? Yes
Evidence type: Observational
Subjects: People

The post Autoimmune disease linked to doubling in depression, anxiety, bipolar risks first appeared on BMJ Group.

Figures reflect growing public and professional awareness and potential impact of COVID-19
But wide regional variations point to inequalities in access to care, say researchers 

Prescriptions for attention deficit hyperactivity disorder (ADHD) in England have risen 18%  year on year since the pandemic. This is higher than previously reported, and masks wide regional variations in prescribing rates, finds research published in the open access journal BMJ Mental Health.

The trends likely reflect growing public and professional awareness of the condition, driven in part by social media, as well as the potential impact of COVID-19, suggest the researchers. But the regional variations point to inequalities in access to care, they add.

ADHD is common in children, with a global prevalence of around 7%, note the researchers, while its prevalence in symptomatic adults is also on the rise, with a reported rate of nearly 7%.

Five drugs are licensed for its treatment in the UK: three stimulants (methylphenidate, dexamfetamine, lisdexamfetamine); and two non-stimulants (atomoxetine, guanfacine). And in the absence or lack of availability of alternative treatment options, such as psychological or behavioural therapy, these drugs have a key role in ADHD management, say the researchers.

Several studies have reported an increase in ADHD prescriptions in England since the COVID-19 pandemic, but most of these studies were based on the old NHS structure—before the introduction of 42 integrated care systems—and/or focused on specific groups or types of drug.

And little is currently known about the potential influence of other factors, such as social deprivation, inequalities, and mental health needs, they add.

To explore this further, they mined the English Prescribing Dataset from April 2019 to March 2024, looking at prescription trends for the 5 currently licensed ADHD drugs at national, regional, and integrated care board (ICB) levels.

The findings showed that prescriptions increased significantly from around 25 items per 1000 people in 2019-20, before the advent of the pandemic to 41.55 items in 2023-24, with an average annual increase of 18% nationally—higher than previously reported.

Methylphenidate remained the most frequently prescribed drug (19 items/1000 people), but the highest increase was for lisdexamfetamine, prescriptions for which increased by 55% year on year, rising from 2.86 items/1000 people in 2019-20 to 8.68 items in 2023-24.

ADHD prescriptions rose in all 7 regions of England, but there were significant regional variations: London saw the highest annual increase of 28%; the Northeast and Yorkshire saw the lowest at 13%.

The second highest change in the annual prescription rate of almost 19.5% was in Southeast England.

Prescribing trends also varied widely at the ICB level. The NHS Birmingham and Solihull ICB witnessed the highest increase in prescriptions of almost 51.5%, but with considerable variation within the ICB itself. The smallest increase of just over 4.5% was in NHS Norfolk and Waveney ICB.

Further analysis showed significant statistical associations between socioeconomic factors and ADHD prescriptions, particularly ethnicity and deprivation, but also age and inequality.

Several factors may explain the substantial rise in prescription rates, say the researchers. “Increased public and professional awareness, partly driven by social media platforms like TikTok and Instagram, has likely encouraged more people to seek assessment, diagnosis and treatment,” they write.

And they caution: “There is a pressing need for research into effective methods for vetting and moderating ADHD-related information on social media platforms to ensure that awareness efforts do not inadvertently spread misinformation.”

The widespread disruption and increased psychological stress levels caused by the COVID-19 pandemic may also have driven up prescribing rates, they suggest.

“While our study has identified significant changes in prescription patterns during and after the pandemic, it is crucial to determine whether these trends represent a temporary shift or a more permanent change in ADHD prescriptions,” they emphasise.

And they conclude: “The significant rise in ADHD prescriptions across England highlights the urgent need for policies that address both regional and socioeconomic disparities in ADHD care access. Targeted efforts should be made to meet the needs of each region by identifying specific barriers to care and their root causes.”

12/03/2025

Notes for editors
Research: Socioeconomic status and prescribing of ADHD medications: a study of ICB-level data in England  Doi: 10.1136/bmjment-2024-301384
Journal: BMJ Mental Health

External funding: None declared

Link to Academy of Medical Sciences press release labelling system
http://press.psprings.co.uk/AMSlabels.pdf

Externally peer reviewed? Yes
Evidence type: Observational
Subjects: People

The post Yearly 18% rise in ADHD prescriptions in England since COVID-19 pandemic first appeared on BMJ Group.

Clear time of day patterns in frame of mind: best early on; worst late at night

Generally, things really do seem better in the morning, with clear differences in self-reported mental health and wellbeing across the day, suggest the findings of a large study published in the open access journal BMJ Mental Health.

People generally wake up feeling in the best frame of mind in the morning but in the worst around midnight, the findings indicate, with day of the week and season of the year also playing their part.

Mental health and wellbeing are dynamic in nature, and subject to change over both short and extended periods, note the researchers. But relatively few studies have looked at how these might change over the course of the day, and those studies that have, have included particular, or only small, groups, they add.

The researchers therefore wanted to explore whether time of day was associated with  variations in mental health (depressive and/or anxiety symptoms), happiness (hedonic wellbeing), life satisfaction, sense of life being worthwhile (eudemonic wellbeing) and loneliness (social wellbeing). They also wanted to find out if these associations varied by day, season, and year.

They analysed data from the University College London COVID-19 Social Study, which began in March 2020, and involved regular monitoring until November 2021, and then additional monitoring up to March 2022.

All studied aspects were measured via questionnaires using validated assessment tools or through single direct questions: “In the past week, how happy did you feel; how satisfied have you been with your life; to what extent have you felt the things you are doing in your life are worthwhile?”

Time stamps on completion of each survey provided information on time of day (continuous from 6 am to midnight); day of the week; season; and year (2020, 2021, 2022).

Information on other potentially influential factors included age groups (18–29, 30–45, 46–59, 60+), gender, ethnicity, educational attainment, employment status, residential area (rural, urban) and diagnosed physical and mental health conditions (yes, no).

Complete information was available for 49, 218 people, three quarters of whom (76.5%) were women. People educated to degree level or above were over represented (68%) while those from ethnic minority backgrounds were under represented (6%). The sample was therefore weighted to reflect population proportions.

Analysis of the data revealed a clear pattern in self-reported mental health and wellbeing across the day, with people generally waking up in the morning feeling best—lowest depressive/anxiety symptoms and loneliness and highest happiness, life satisfaction, and worthwhile ratings—and feeling worst around midnight.

The influence of day of the week was less clear-cut, with more variation in mental health and wellbeing during weekends than on week days.

Happiness, life satisfaction, and worthwhile ratings were all higher on Mondays and Fridays than on Sundays, and happiness was also higher on Tuesdays. But there was no evidence that loneliness differed across days of the week.

There was clear evidence of a seasonal influence on mood, however. Compared with winter, people tended to have lower levels of depressive and anxiety symptoms and loneliness, and higher levels of happiness, life satisfaction, and feeling that life was worthwhile in other seasons.

And mental health was best in the summer across all outcomes. But the season didn’t affect the associations observed across the day, however.

Mental health and wellbeing also steadily improved from 2020, the first year of the COVID-19 pandemic.

This is an observational study, and as such, can’t establish cause. And when people chose to fill in their questionnaires might have influenced the findings, say the researchers. No information was available for sleep cycles, latitude, or weather, all of which may also have been influential, they add.

But the changes in mental health and wellbeing across the day might be explained by the physiological changes associated with the body clock, they suggest.

“For example, cortisol peaks shortly after waking and reaches its lowest levels around bedtime. However, it is important to acknowledge the differences between weekends and weekdays,” they write.

“Given there is little evidence that physiological processes differ across different days of the week, differences might be related to other factors that drive [mental health and wellbeing] changes over the course of the day. This could include contextual factors and sequence of daily activities, which are likely to be different between weekends and weekdays.”

The similar time of day patterns in mental health and wellbeing, irrespective of the seasons, is surprising, as one of the main reasons for seasonal changes in frame of mind is the number of daylight hours, say the researchers.

“Other drivers of the seasonal variation in [mental health and wellbeing] could include weather (temperature, precipitation, humidity) as well as various sociocultural cycles, including cultural holidays, norms, and employment patterns,” they suggest.

The findings have implications for service delivery and clinical assessments, say the researchers. “Finally, in relation to public health, our findings indicate that people’s [mental health  and wellbeing] tends to be lowest around midnight, mid-week, and in winter. This should be considered when planning service and resource provision.”

05/02/2025

Notes for editors
Research: Will things feel better in the morning? A time-of-day analysis of mental health and wellbeing from nearly 1 million observations Doi: 10.1136/bmjment-2024-301418
Journal: BMJ Mental Health

External funding: Nuffield Foundation; MARCH Mental Health Network

Link to Academy of Medical Sciences press release labelling system
http://press.psprings.co.uk/AMSlabels.pdf

Externally peer reviewed? Yes
Evidence type: Observational
Subjects: People

The post Generally, things really do seem better in the morning, large study suggests first appeared on BMJ Group.

These oral microbiome variations are different to the associations with life stress and mental health in the gut microbiome

The number and type of microbes present in the saliva of pregnant women differ according to whether they are experiencing life stress and symptoms of anxiety, depression and post-traumatic stress disorder (PTSD), finds a study published in the open access journal BMJ Mental Health.

Although several studies have shown links between the diversity of microbes in the gastrointestinal tract and stress, anxiety and depression in pregnant women and new mothers, no previous study has looked at the association between the type and number of microorganisms in the mouth and throat—oral microbiome—and maternal mental health.

The study included 224 pregnant women enrolled in the Michigan Prenatal Stress Study assessed for recent stresses and mental health symptoms during their second trimester. Women were asked to provide saliva samples during the week of their assessments.

The results showed the oral microbiome varied with whether women had reported life stress, anxiety, depression or post-traumatic stress disorder (PTSD) symptoms during the assessments.

Oral microbiomes of women with high anxiety or depression symptoms showed high alpha diversity, which means they included many types of microbe species present at relatively even levels, i.e. it was less likely that one species dominated.

Oral microbiomes of women with high levels of PTSD symptoms instead showed high beta diversity, which means the specific microbe species in their saliva notably differed from the species found in women with low PTSD symptoms.

Specific stress and mental health traits were also associated with high levels of certain microbe species. Women who had experienced recent life stress had a greater abundance of species in the phylum Proteobacteria, while Spirochaetes was more abundant in women with high levels of depression symptoms. Greater numbers of Dialister species and species in the phylum Firmicutes were seen in women with levels of anxiety and depression symptoms, and species in the genus Eikenella were elevated in women with high anxiety, depression or PTSD.

Twenty two potential covariates were investigated to see whether they influenced changes in the microbiome. This analysis revealed that cigarette smoking could explain 7.2% of the variance seen in oral microbiomes, dental problems could explain 3.1%, intimate partner violence could explain 4.1% and unplanned pregnancy could explain 2%.

The authors highlight several study limitations, including insufficient data to examine other potential covariates related to diet and body weight, and the focus on a single time point in pregnancy. Women self-reported anxiety and depression measures which could have affected their accuracy, and there was no investigation of potential sources of microbes, such as the lower gut and long-term oral health.

The authors conclude, “Our study shows that numerous aspects of the oral microbiome in pregnancy are associated with women’s life stress and mental health. Importantly, these associations differ from studies of the gut microbiome and studies of non-pregnant people.”

They add that their findings suggest that the oral microbiome could be a potential target for interventions to improve poor psychological well-being during pregnancy.

“Successful targeting of the gut microbiome with probiotic treatment to improve maternal mental health could be extended in future studies to target oral cavity microbes through dietary changes, making recommendations for improving oral health, and probiotic treatments that might benefit mothers struggling with high life stress and poor mental health,” they say.

20/11/2024

Notes for editors
Research: Stress and mental health symptoms in early pregnancy are associated with the oral microbiome Doi: 10.1136//bmjment-2024-301100
Journal: BMJ Mental Health

External funding: National Institutes of Health; Michigan State University College of Social Science Faculty Initiative Fund.

Link to Academy of Medical Sciences press release labelling system
http://press.psprings.co.uk/AMSlabels.pdf

Externally peer reviewed? Yes
Evidence type: Observational
Subjects: People

The post Oral microbiome varies with life stress and mental health symptoms in pregnant women first appeared on BMJ Group.

But further research needed to understand effects of heavy use and cannabis potency

Lifetime cannabis use is associated with several changes in brain structure and function in later life, suggests an observational study, but these associations may not be causal, finds a genetic analysis of the same data, published in the open access journal BMJ Mental Health.

Some other unidentified factors may explain the differences found, say the researchers, who nevertheless emphasise that further research is needed to fully understand the effects of heavy use and cannabis potency on the brain.

Cannabis use has increased worldwide following its legalisation for medical and recreational purposes. But this has happened in the absence of a thorough understanding of its potential long term effects on the brain, say the researchers.

Its use is associated with deleterious effects on neurocognitive performance, brain structure, and function. And it’s not known if there is a safe threshold, they add.

But previously published observational studies have not been able to confirm that cannabis caused the changes seen among regular users of the drug, and few of these studies have included older people.

In a bid to strengthen the evidence base, the researchers used Mendelian randomisation, a technique that uses genetic variants as proxies for a particular risk factor—in this case cannabis use or dependence—to obtain genetic evidence in support of a particular outcome—in this study brain structure among older lifetime users.

They drew on 15,896 cannabis users participating in the UK Biobank for whom genetic profiling (2012-13) and brain imaging (MRI scans) (2014-19) data were available.

Participants reported if they had ‘ever taken cannabis’, with response options ranging from once or twice to more than 100 times.

All participants who responded ‘yes’ were categorised as lifetime cannabis users (3641; average age 61), with ‘no’ responders categorised as the comparison group (12,225; average age 64).

Cannabis users were further divided into low frequency users, defined as lifetime cannabis use of up to 10 times, and high frequency users defined as lifetime use of 11–100+ times. Participants also reported how old they were when they last used the drug.

The researchers accounted for a range of potentially influential factors, including: age at first scan (in years), sex, and age-by-sex interaction; level of deprivation; employment status; qualifications; smoking and alcohol consumption; blood pressure; weight (BMI); mental state; and 613 brain imaging-related variables.

After adjusting for these factors, cannabis use was associated with multiple measures of changes in brain structure and function.

Participants who had ever used cannabis had poorer white matter integrity, a constituent of the brain that is important for cognitive function. And this was particularly evident in the corpus callosum, the main route of communication between the left and right sides of the brain.

Cannabis users also had weaker resting state neuronal connectivity in brain regions which make up underlying the default mode network, thought to be active during mind wandering or daydreaming.

These areas of the brain are densely packed with cannabinoid receptors, the researchers point out.

Neither the duration of cannabis abstinence nor the frequency of cannabis use were strongly associated with any of the observed findings in brain structure and function.

But there were some notable differences between the sexes: while significant associations were observed in six specific brain regions among the men, the observations seen in women were spread across 24 brain structures and functional regions.

Most associations were observed in functional connectivity among the men; in women, associations were primarily seen in white matter integrity, suggesting that cannabis use affects the sexes differently, say the researchers.

When Mendelian randomisation was applied to the findings, no significant associations emerged between genetically predicted cannabis dependence/abuse or lifetime cannabis use.

“To the best of our knowledge, this is the largest observational study of relationships between cannabis use and brain structure and function to date, and the first Mendelian randomisation investigation,” say the researchers.

“Cannabis users had significant differences in brain structure and function, most markedly for markers of lower white matter microstructure integrity. Genetic analyses found no support for causal relationships underlying these observed associations,” they add.

There are several possible explanations for the differences between the observational and Mendelian randomisation findings, they suggest.

An unmeasured variable, such as family history, dietary intake, or use of certain medications, might have influenced the observational findings. And the Mendelian randomisation analyses might have had less statistical power to detect small effects.

Mendelian randomisation also assesses the lifelong impact of cannabis use, while changes in observational studies might be due to factors occurring at different points in a person’s life rather than cumulative impact across the life course, suggest the researchers.

They also acknowledge the limitations of using the UK Biobank, which is made up of predominantly healthy White participants. And few of those included in this study had cannabis use disorders.

The researchers were also unable to look at the time points during life that might be critical for cannabis effects, and the study relied on participants’ recall concerning the amount or frequency of cannabis use during their lifetime, which may have been inaccurate.

They caution: “Our results need to be interpreted with careful consideration. Additional research is needed to understand the effects of heavy cannabis use in this population, including considerations of potency and related information to inform public policy.”

30/10/2024

Notes for editors
Imaging study: Association between cannabis use and brain structure and function: an observational and Mendelian randomisation study Doi: 10.1136/bmjment-2024-301065
Journal: BMJ Mental Health

External funding: Wellcome: Society for the Study of Addiction; Department of Veterans Affairs Office of Research and Development

Link to Academy of Medical Sciences press release labelling system
http://press.psprings.co.uk/AMSlabels.pdf

Externally peer reviewed? Yes
Evidence type: Observational + Mendelian Randomisation
Subjects: People

The post Brain changes seen in lifetime cannabis users may not be causal first appeared on BMJ Group.

Findings underscore importance of efforts to bolster mental resilience, say researchers

The ability to cope well with, and adapt to, challenging life circumstances and events in older age is linked to a lower risk of death, suggests a large nationally representative study, published in the open access journal BMJ Mental Health.

The findings underscore the importance of efforts to bolster mental resilience, conclude the researchers.

The available evidence suggests that mental resilience is a dynamic and active process influenced by various factors, including sex, hormones, and the genes regulating the body’s stress response. This capacity is believed to evolve and vary across different periods of the life cycle, say the researchers.

In older age, good coping skills can help offset the negative impact of long term conditions and subsequent disability. And while the ability to bounce back physically after illness and trauma is associated with slower ageing and the risk of death, it’s not clear if mental resilience might have similar effects, they explain.

To explore this further, the researchers mined the US Health and Retirement Study (HRS), a long term nationally representative study of US adults aged at least 50. This study began in 1992 and includes information on the economic, health, marital and family status of participants who are monitored every 2 years.

The researchers drew on two waves (2006–08) of HRS data, when questions on mental resilience were collected for the first time, and included a total of 10,569 participants with complete data in the final analysis. Their average age was 66; 59% of them were women.

Mental resilience was assessed using a validated scale encompassing qualities, such as perseverance, calmness, a sense of purpose, self-reliance and the recognition that certain experiences have to be faced alone. The average score of the entire sample was 9.18 (range 0-12).

Participants were followed up until death or the end of May 2021, whichever came first. During an average tracking period of 12 years, 3489 people died.

An almost linear association emerged between mental resilience score and death from any cause: the higher the score, the lower was the risk of death, with this association stronger in women than in men.

Resilience scores were divided into quartiles (25%) and linked to 10-year survival probabilities. These were 61% for those in the bottom quartile (1), rising to 72% and 79% for the middle quartiles (2 and 3), and 84% for those in the top quartile (4).

Survival analysis showed that those in the highest quartile were 53% less likely to die in the next 10 years than those in the lowest.

This association remained statistically significant after adjusting for marital status, sex, race, and weight (BMI), but fell to 46% after factoring in ill health (diabetes, cancer, and cardiovascular disease) and to 38% after factoring in an unhealthy lifestyle.

In all, the risk of death was 20% lower (2nd quartile), 27% lower (3rd), and 38% lower (4th) in those with higher mental resilience scores than it was in those with the lowest scores (Ist quartile), once potentially influential factors had been accounted for.

This is an observational study, and as such, no firm conclusions can be drawn about causality. And the researchers acknowledge that the potential influence of genetic and hormonal factors and childhood adversity weren’t considered. The analysis also relied on baseline data, overlooking potentially influential changes during the monitoring period.

“Various factors, including but not limited to, meaning in life, positive emotions, self-rated health and satisfaction with social support, have been identified as potential influences on psychological resilience,” they explain.

“Triggering these positive emotions may enhance the protective effects of psychological resilience and mitigate the negative impact of accumulated adversity on mental health in adults.”

They conclude: “The findings underscore the potential effectiveness of interventions aimed at promoting psychological resilience in order to mitigate mortality risks.”

04/09/2024

Notes for editors
Research: Association between psychological resilience and all cause mortality in the Health and Retirement Study Doi: 10.1136/bmjment-2024-301064
Journal: BMJ Mental Health

External funding: Pearl River Scholar Program of Guangdong Province

Link to Academy of Medical Sciences press release labelling system
http://press.psprings.co.uk/AMSlabels.pdf

Externally peer reviewed? Yes
Evidence type: Observational
Subjects: People

The post Ability to cope well with adversity in older age linked to lower death risk first appeared on BMJ Group.

Linked to major depression, post-traumatic stress, anorexia nervosa, suicide attempts
Vigilance required for those affected to ward off psychiatric problems, say researchers

The hyperactivity disorder, usually referred to as ADHD, is an independent risk factor for several common and serious mental health issues, finds research published in the open access journal BMJ Mental Health.

It is associated with major depression, post traumatic stress disorder, the eating disorder anorexia nervosa, and suicide attempts, the findings show, prompting the researchers to recommend vigilance by health professionals in a bid to ward off these disorders later on.

Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental condition in children and teens that extends into adulthood in up to around two thirds of cases. Worldwide, its prevalence is estimated to be around 5% in children/teens and 2.5% in adults.

ADHD has been linked to mood and anxiety disorders in observational studies, but it’s not known if it’s causally associated with other mental ill health.

To try and find out, the researchers used Mendelian randomisation, a technique that uses genetic variants as proxies for a particular risk factor—in this case ADHD—to obtain genetic evidence in support of a particular outcome—in this study, 7 common mental health issues.

These were: major clinical depression; bipolar disorder; anxiety disorder; schizophrenia; post traumatic stress disorder (PTSD); anorexia nervosa; and at least one suicide attempt.

The researchers initially used the technique to establish potential links between ADHD and the 7 disorders. They then used it to see if disorders associated with ADHD could potentially be responsible for the effects detected in the first analysis. Finally, they pooled the data from both analyses to calculate the direct and indirect effects of ADHD. 

There was no evidence for a causal link between ADHD and bipolar disorder, anxiety, or schizophrenia, the results of the analysis showed.

But there was evidence for a causal link with a heightened risk of anorexia nervosa (28%), and evidence that ADHD both caused (9% heightened risk), and was caused by (76% heightened risk), major clinical depression. 

And after adjusting for the influence of major depression, a direct causal association with both suicide attempt (30% heightened risk) and PTSD (18% heightened risk) emerged.

The researchers caution that while Mendelian randomisation is less prone than observational studies to the influence of unmeasured factors and reverse causality—whereby ADHD could be a consequence of the various disorders studied rather than the other way round—it is not without its limitations.

For example, the same gene may be associated with different traits, making it difficult to pinpoint the relevant causal effect, they point out. Only people of European ancestry were included so the findings might not apply to other ethnicities.

Nevertheless, the researchers conclude that their findings should encourage clinicians to be more proactive when treating people with ADHD.

”This study opens new insights into the paths between psychiatric disorders. Thus, in clinical practice, patients with ADHD should be monitored for the psychiatric disorders included in this study and preventive measures should be initiated if necessary,” they write.  

05/09/2023

Notes for editors
Research: Understanding the causal relationships of attentiondeficit/hyperactivity disorder with mental disorders and suicide attempt: a network Mendelian randomisation study doi 10.1136/bmjment-2022-300642
Journal: BMJ Mental Health

Funding: None declared

Link to Academy of Medical Sciences press release labelling system http://press.psprings.co.uk/AMSlabels.pdf

Externally peer reviewed? Yes
Evidence type: Mendelian Randomisation study
Subjects: People

The post Hyperactivity disorder (ADHD) risk factor for serious mental health issues first appeared on BMJ Group.