The Prevalence of Behavioural Symptoms and Psychiatric Disorders in Hadza Children.

The worldwide pooled prevalence of psychiatric disorders in children is 13.4%. Studying the prevalence of childhood psychiatric disorders across radically different economic systems and social structures could indicate universal factors leading to their development. The prevalence of childhood psychiatric disorders in a mixed-subsistence foraging society has not been studied. The Strengths and Difficulties Questionnaire and the Development and Well-Being Assessment were used to compare the prevalence of behavioural symptoms and psychiatric disorders in Hadza children aged 5-16 years (n = 113) to a nationally representative sample from England (n = 18,029) using a cross-sectional study design. Emotional problems, conduct problems and hyperactivity were lower in the Hadza children. Prosocial behaviour and peer problems were higher in Hadza children. 3.6% of Hadza children met the criteria for a psychiatric disorder compared to 11.8% of English children. All psychiatric disorders in Hadza children were co-morbid with autism spectrum disorder. No child from the Hadza group met the criteria for an emotional, behaviour or eating disorder. Further work should study the factors which lead to the different prevalence of psychiatric disorders in Hadza children.

Reconsidering the Use of Population Health Surveys for Monitoring of Mental Health.

Monitoring of the mental health status of the population and assessment of its determinants are 2 of the most relevant pillars of public mental health, and data from population health surveys could be instrumental to support them. Although these surveys could be an important and suitable resource for these purposes, due to different limitations and challenges, they are often relegated to the background behind other data sources, such as electronic health records. These limitations and challenges include those related to measurement properties and cross-cultural validity of the tools used for the assessment of mental disorders, their degree of representativeness, and possible difficulties in the linkage with other data sources. Successfully addressing these limitations could significantly increase the potential of health surveys in the monitoring of mental disorders and ultimately maximize the impact of the relevant policies to reduce their burden at the population level. The widespread use of data from population health surveys, ideally linked to electronic health records data, would enhance the quality of the information available for research, public mental health decision-making, and ultimately addressing the growing burden of mental disorders.

Prevalence and variability of depressive symptoms in Europe: update using representative data from the second and third waves of the European Health Interview Survey (EHIS-2 and EHIS-3).

BACKGROUND: Assessing the prevalence of clinically relevant depressive symptoms and their possible variation by country and over time could be a valuable resource to inform the development of public health policies and preventive resources to reduce mental health burden. We aimed to assess cross-national differences in the point prevalence of clinically relevant depressive symptoms in Europe in 2018-20, and to evaluate point prevalence differences between countries and over time between 2013-15 and 2018-20. METHODS: In this population-based study, data from participants in the second and third waves of the European Health Interview Survey (EHIS-2 from 2013 to 2015 and EHIS-3 from 2018 to 2020) from 30 European countries were used (n=542 580). From the total sample, 283 692 participants belonging to EHIS-3 were included in the study (52·4% women and 47·5% men). The non-response in EHIS-3 ranged by country, from 12% to 78%. Point prevalence of clinically relevant depressive symptoms was evaluated using a cutoff score of 10 or more for the 8-item version of the Patient Health Questionnaire. Crude prevalence ratios and adjusted prevalence ratios (aPRs) were obtained to assess differences in the prevalence between countries and over time within countries. FINDINGS: The point prevalence of clinically relevant depressive symptoms in Europe in 2018-20 was 6·54% (95% CI 6·34-6·73), ranging across countries from 1·85% (1·53-2·17) in Greece to 10·72% (10·04-11·40) in Sweden. Compared with the other European countries, those with the lowest aPRs were Greece, Serbia, and Cyprus and those with the highest aPRs were Belgium, Slovenia, and Croatia. A small but significant increase in the prevalence between EHIS-2 and EHIS-3 was observed (aPR 1·11 [1·07-1·14]). A wide variability over time in the point prevalence within countries was observed, ranging from an aPR of 0·63 (0·54-0·74) in Hungary to 1·88 (1·53-2·31) in Slovenia. INTERPRETATION: This study, based on large and representative datasets and a valid and reliable screening tool for the assessment of depression, indicates that the point prevalence of clinically relevant depressive symptoms in Europe from 2013 to 2020 remains relatively stable, with wide variability between countries. These findings could be considered a baseline for monitoring the prevalence of clinically relevant depressive symptoms in Europe, and could inform policy for the development of preventive strategies for depression both at a country and European level. FUNDING: Center for Biomedical Research in Epidemiology and Public Health Network and AGAUR.

Organisational and student characteristics, fidelity, funding models, and unit costs of recovery colleges in 28 countries: a cross-sectional survey.

BACKGROUND: Recovery colleges were developed in England to support the recovery of individuals who have mental health symptoms or mental illness. They have been founded in many countries but there has been little international research on recovery colleges and no studies investigating their staffing, fidelity, or costs. We aimed to characterise recovery colleges internationally, to understand organisational and student characteristics, fidelity, and budget. METHODS: In this cross-sectional study, we identified all countries in which recovery colleges exist. We repeated a cross-sectional survey done in England for recovery colleges in 28 countries. In both surveys, recovery colleges were defined as services that supported personal recovery, that were coproduced with students and staff, and where students learned collaboratively with trainers. Recovery college managers completed the survey. The survey included questions about organisational and student characteristics, fidelity to the RECOLLECT Fidelity Measure, funding models, and unit costs. Recovery colleges were grouped by country and continent and presented descriptively. We used regression models to explore continental differences in fidelity, using England as the reference group. FINDINGS: We identified 221 recovery colleges operating across 28 countries, in five continents. Overall, 174 (79%) of 221 recovery colleges participated. Most recovery colleges scored highly on fidelity. Overall scores for fidelity (ß=-2·88, 95% CI 4·44 to -1·32; p=0·0001), coproduction (odds ratio [OR] 0·10, 95% CI 0·03 to 0·33; p<0·0001), and being tailored to the student (OR 0·10, 0·02 to 0·39; p=0·0010), were lower for recovery colleges in Asia than in England. No other significant differences were identified between recovery colleges in England, and those in other continents where recovery colleges were present. 133 recovery colleges provided data on annual budgets, which ranged from €0 to €2 550 000, varying extensively within and between continents. From included data, all annual budgets reported by the college added up to €30 million, providing 19 864 courses for 55 161 students. INTERPRETATION: Recovery colleges exist in many countries. There is an international consensus on key operating principles, especially equality and a commitment to recovery, and most recovery colleges achieve moderate to high fidelity to the original model, irrespective of the income band of their country. Cultural differences need to be considered in assessing coproduction and approaches to individualising support. FUNDING: National Institute for Health and Care Research.

Associations between air pollution and mental health service use in dementia: a retrospective cohort study.

BACKGROUND: Little is known about the role of air pollution in how people with dementia use mental health services. OBJECTIVE: We examined longitudinal associations between air pollution exposure and mental health service use in people with dementia. METHODS: In 5024 people aged 65 years or older with dementia in South London, high resolution estimates of nitrogen dioxide (NO2) and particulate matter (PM2.5 and PM10) levels in ambient air were linked to residential addresses. Associations between air pollution and Community Mental Health Team (CMHT) events (recorded over 9 years) were examined using negative binomial regression models. Cognitive function was measured using the Mini Mental State Examination (MMSE) and health and social functioning was measured using the Health of the Nation Outcomes Scale (HoNOS65+). Associations between air pollution and both MMSE and HoNOS65+ scores were assessed using linear regression models. FINDINGS: In the first year of follow-up, increased exposure to all air pollutants was associated with an increase in the use of CMHTs in a dose-response manner. These associations were strongest when we compared the highest air pollution quartile (quartile 4: Q4) with the lowest quartile (Q1) (eg, NO2: adjusted incidence rate ratio (aIRR) 1.27, 95% CI 1.11 to 1.45, p<0.001). Dose-response patterns between PM2.5 and CMHT events remained at 5 and 9 years. Associations were strongest for patients with vascular dementia. NO2 levels were linked with poor functional status, but not cognitive function. CONCLUSIONS: Residential air pollution exposure is associated with increased CMHT usage among people with dementia. CLINICAL IMPLICATIONS: Efforts to reduce pollutant exposures in urban settings might reduce the use of mental health services in people with dementia, freeing up resources in already considerably stretched psychiatric services.

Reliability and cross-country equivalence of the 8-item version of the Patient Health Questionnaire (PHQ-8) for the assessment of depression: results from 27 countries in Europe.

Background: The 8-item version of the Patient Health Questionnaire (PHQ-8) is one of the self-reported questionnaires most frequently used worldwide for the screening and severity assessment of depression. However, in some European countries its reliability is unknown, and it is unclear whether its psychometric properties vary between European countries. Therefore, the aim of this study was to assess the internal structure, reliability and cross-country equivalence of the PHQ-8 in Europe. Methods: All participants from the 27 countries included in the second wave of the European Health Interview Survey (EHIS-2) between 2014 and 2015 with complete information on the PHQ-8 were included (n = 258,888). The internal structure of the PHQ-8 was assessed using confirmatory factor analyses (CFA) for categorical items. Additionally, the reliability of the questionnaire was assessed based on the internal consistency, Item Response Theory information functions, and item-discrimination (using Graded Response Models), and the cross-country equivalence based on multi-group CFA. Findings: The PHQ-8 shows high internal consistency for all countries. The countries in which the PHQ-8 was more reliable were Romania, Bulgaria and Cyprus and less reliable were Iceland, Norway and Austria. The PHQ-8 item with highest discrimination was item 2 (feeling down, depressed, or hopeless) in 24 of the 27 countries. Measurement invariance between countries in Europe was observed from multigroup CFA at the configural, metric and scalar levels. Interpretation: The results from our study, likely the largest study to the date assessing the internal structure, reliability and cross-country comparability of a self-reported mental health assessment measure, shows that the PHQ-8 has an adequate reliability and cross-country equivalence across the 27 European countries included. These results highlight the suitability of the comparisons of the PHQ-8 scores in Europe. They could be helpful to improve the screening and severity assessment of depressive symptoms at the European level. Funding: This work was partially funded by CIBER Epidemiology and Public Health (CIBERESP) as part of the Intramural call of 2021 (ESP21PI05).

Evidence-based Recovery Colleges: developing a typology based on organisational characteristics, fidelity and funding.

PURPOSE: Recovery Colleges (RCs) have been implemented across England with wide variation in organisational characteristics. The purpose of this study is to describe RCs across England in terms of organisational and student characteristics, fidelity and annual spending, to generate a RC typology based on characteristics and to explore the relationship between characteristics and fidelity. METHODS: All RC in England meeting criteria on recovery orientation, coproduction and adult learning were included. Managers completed a survey capturing characteristics, fidelity and budget. Hierarchical cluster analysis was conducted to identify common groupings and generate an RC typology. RESULTS: Participants comprised 63 (72%) of 88 RC in England. Fidelity scores were high (median 11, IQR 9-13). Both NHS and strengths-focussed RCs were associated with higher fidelity. The median annual budget was £200,000 (IQR £127,000-£300,000) per RC. The median cost per student was £518 (IQR £275-£840), cost per course designed was £5,556 (IQR £3,000-£9,416) and per course run was £1,510 (IQR £682-£3,030). The total annual budget across England for RCs is an estimated £17.6 m including £13.4 m from NHS budgets, with 11,000 courses delivered to 45,500 students. CONCLUSION: Although the majority of RCs had high levels of fidelity, there were sufficiently pronounced differences in other key characteristics to generate a typology of RCs. This typology might prove important for understanding student outcomes and how they are achieved and for commissioning decisions. Staffing and co-producing new courses are key drivers of spending. The estimated budget for RCs was less than 1% of NHS mental health spending.

The relationship between air pollution and multimorbidity: Can two birds be killed with the same stone?

Air pollution and multimorbidity are two of the most important challenges for Public Health worldwide. Although there is a large body of evidence linking air pollution with the development of different single chronic conditions, the evidence about the relationship between air pollution and multimorbidity (the co-occurrence of multiple long-term conditions) is sparse. To obtain evidence about this relationship could be challenging and different aspects should be considered, such as its multifaceted and complex nature, the specific pollutants and their potential influence on health, their levels of exposure over time, or the data that could be used for its study. This evidence could be instrumental to inform the development of new recommendations and measures to reduce harmful levels of air pollutants, as means to prevent the development of multimorbidity and reduce its burden.

Ethnic differences in physical and mental multimorbidity in working age adults with a history of depression and/or anxiety.

BACKGROUND: The current study used data from an ethnically diverse population from South London to examine ethnic differences in physical and mental multimorbidity among working age (18-64 years) adults in the context of depression and anxiety. METHOD: The study included 44 506 patients who had previously attended Improving Access to Psychological Therapies services in the London Borough of Lambeth. Multinomial logistic regression examined cross-sectional associations between ethnicity with physical and mental multimorbidity. Patterns of multimorbidity were identified using hierarchical cluster analysis. RESULTS: Within 44 056 working age adults with a history of depression or anxiety from South London there were notable ethnic differences in physical multimorbidity. Adults of Black Caribbean ethnicity were more likely to have physical multimorbidity [adjusted relative risk ratio (aRRR) = 1.25, 95% confidence interval (CI) 1.15-1.36] compared to adults of White ethnicity. Relative to adults of White ethnicity, adults of Asian ethnicity were more likely to have physical multimorbidity at higher thresholds only (e.g. 4 + conditions; aRRR = 1.53, 95% CI 1.17-2.00). Three physical (atopic, cardiometabolic, mixed) and three mental (alcohol/substance use, common/severe mental illnesses, personality disorder) multimorbidity clusters emerged. Ethnic minority groups with multimorbidity had a higher probability of belonging to the cardiometabolic cluster. CONCLUSION: In an ethnically diverse population with a history of common mental health disorders, we found substantial between- and within-ethnicity variation in rates of physical, but not mental, multimorbidity. The findings emphasised the value of more granular definitions of ethnicity when examining the burden of physical and mental multimorbidity.

Multimorbidity clusters among people with serious mental illness: a representative primary and secondary data linkage cohort study.

BACKGROUND: People with serious mental illness (SMI) experience higher mortality partially attributable to higher long-term condition (LTC) prevalence. However, little is known about multiple LTCs (MLTCs) clustering in this population. METHODS: People from South London with SMI and two or more existing LTCs aged 18+ at diagnosis were included using linked primary and mental healthcare records, 2012-2020. Latent class analysis (LCA) determined MLTC classes and multinominal logistic regression examined associations between demographic/clinical characteristics and latent class membership. RESULTS: The sample included 1924 patients (mean (s.d.) age 48.2 (17.3) years). Five latent classes were identified: 'substance related' (24.9%), 'atopic' (24.2%), 'pure affective' (30.4%), 'cardiovascular' (14.1%), and 'complex multimorbidity' (6.4%). Patients had on average 7-9 LTCs in each cluster. Males were at increased odds of MLTCs in all four clusters, compared to the 'pure affective'. Compared to the largest cluster ('pure affective'), the 'substance related' and the 'atopic' clusters were younger [odds ratios (OR) per year increase 0.99 (95% CI 0.98-1.00) and 0.96 (0.95-0.97) respectively], and the 'cardiovascular' and 'complex multimorbidity' clusters were older (ORs 1.09 (1.07-1.10) and 1.16 (1.14-1.18) respectively). The 'substance related' cluster was more likely to be White, the 'cardiovascular' cluster more likely to be Black (compared to White; OR 1.75, 95% CI 1.10-2.79), and both more likely to have schizophrenia, compared to other clusters. CONCLUSION: The current study identified five latent class MLTC clusters among patients with SMI. An integrated care model for treating MLTCs in this population is recommended to improve multimorbidity care.

Physical multimorbidity, depressive symptoms, and social participation in adults over 50 years of age: findings from the English Longitudinal Study of Ageing.

OBJECTIVES: The aim of the current study was to identify specific patterns of physical multimorbidity and examine how these patterns associated with changes in social participation over time. METHODS: We used latent class analysis to identify clusters of physical multimorbidity in 11,391 older adults. Mixed effects regression models were used to assess associations between physical multimorbidity clusters and changes in social participation over 15 years. RESULTS: Four clusters of physical multimorbidity were identified. All physical multimorbidity clusters were associated with a reduction in cultural engagement (e.g. visits to theatre, cinema, museums) over time, with the strongest association seen in the complex/multisystem cluster (ß = -0.26, 95% CI = -0.38 to -0.15). Similar results emerged for leisure activities. Adjusting for depressive symptoms fully attenuated some associations. All physical multimorbidity clusters were associated with an increase in civic participation over time. CONCLUSIONS: Physical multimorbidity reduced some aspects of social participation over time, with specific combinations of conditions having increased risk of reductions.Supplemental data for this article is available online at http://dx.doi.org/10.1080/13607863.2021.2017847.

Associations between air pollution and multimorbidity in the UK Biobank: A cross-sectional study.

Background: Long-term exposure to air pollution concentrations is known to be adversely associated with a broad range of single non-communicable diseases, but its role in multimorbidity has not been investigated in the UK. We aimed to assess associations between long-term air pollution exposure and multimorbidity status, severity, and patterns using the UK Biobank cohort. Methods: Multimorbidity status was calculated based on 41 physical and mental conditions. We assessed cross-sectional associations between annual modeled particulate matter (PM)2.5, PMcoarse, PM10, and nitrogen dioxide (NO2) concentrations (µg/m3-modeled to residential address) and multimorbidity status at the baseline assessment (2006-2010) in 364,144 people (mean age: 52.2 ± 8.1 years, 52.6% female). Air pollutants were categorized into quartiles to assess dose-response associations. Among those with multimorbidity (≥2 conditions; n = 156,395) we assessed associations between air pollutant exposure levels and multimorbidity severity and multimorbidity patterns, which were identified using exploratory factor analysis. Associations were explored using generalized linear models adjusted for sociodemographic, behavioral, and environmental indicators. Results: Higher exposures to PM2.5, and NO2 were associated with multimorbidity status in a dose-dependent manner. These associations were strongest when we compared the highest air pollution quartile (quartile 4: Q4) with the lowest quartile (Q1) [PM2.5: adjusted odds ratio (adjOR) = 1.21 (95% CI = 1.18, 1.24); NO2: adjOR = 1.19 (95 % CI = 1.16, 1.23)]. We also observed dose-response associations between air pollutant exposures and multimorbidity severity scores. We identified 11 multimorbidity patterns. Air pollution was associated with several multimorbidity patterns with strongest associations (Q4 vs. Q1) observed for neurological (stroke, epilepsy, alcohol/substance dependency) [PM2.5: adjOR = 1.31 (95% CI = 1.14, 1.51); NO2: adjOR = 1.33 (95% CI = 1.11, 1.60)] and respiratory patterns (COPD, asthma) [PM2.5: adjOR = 1.24 (95% CI = 1.16, 1.33); NO2: adjOR = 1.26 (95% CI = 1.15, 1.38)]. Conclusions: This cross-sectional study provides evidence that exposure to air pollution might be associated with having multimorbid, multi-organ conditions. Longitudinal studies are needed to further explore these associations.

Recovery Colleges Characterisation and Testing in England (RECOLLECT): rationale and protocol.

BACKGROUND: Recovery Colleges are a relatively recent initiative within mental health services. The first opened in 2009 in London and since then numbers have grown. They are based on principles of personal recovery in mental health, co-production between people with lived experience of mental health problems and professionals, and adult learning. Student eligibility criteria vary, but all serve people who use mental health services, with empirical evidence of benefit. Previously we developed a Recovery College fidelity measure and a preliminary change model identifying the mechanisms of action and outcomes for this group, which we refer to as service user students. The Recovery Colleges Characterisation and Testing (RECOLLECT) study is a five-year (2020-2025) programme of research in England. The aim of RECOLLECT is to determine Recovery Colleges' effectiveness and cost-effectiveness, and identify organisational influences on fidelity and improvements in mental health outcomes.  METHODS: RECOLLECT comprises i) a national survey of Recovery Colleges, ii) a prospective cohort study to establish the relationship between fidelity, mechanisms of action and psychosocial outcomes, iii) a prospective cohort study to investigate effectiveness and cost-effectiveness, iv) a retrospective cohort study to determine the relationship between Recovery College use and outcomes and mental health service use, and v) organisational case studies to establish the contextual and organisational factors influencing fidelity and outcomes. The programme has been developed with input from individuals who have lived experience of mental health problems. A Lived Experience Advisory Panel will provide input into all stages of the research. DISCUSSION: RECOLLECT will provide the first rigorous evidence on the effectiveness and cost effectiveness of Recovery Colleges in England, to inform their prioritising, commissioning, and running. The validated RECOLLECT multilevel change model will confirm the active components of Recovery Colleges. The fidelity measure and evidence about the fidelity-outcome relationship will provide an empirically-based approach to develop Recovery Colleges, to maximise benefits for students. Findings will be disseminated through the study website (researchintorecovery.com/recollect) and via national and international Recovery College networks to maximise impact, and will shape policy on how Recovery Colleges can help those with mental health problems lead empowered, meaningful and fulfilling lives.

Prospective associations between depression and risk of hospitalisation for infection: Findings from the UK Biobank.

BACKGROUND: Associations between depression and non-communicable disease have been well-described. However, the evidence for its role in the development of infectious disease is less understood. We aimed to examine prospective associations between depression and risk of hospitalisation for infection in middle-aged adults from the UK Biobank (linked with Hospital Episode Statistics) and assessed the role of several depression-related factors. METHODS: We assessed prospective associations between depression status at the baseline assessment (2006-2010) and hospitalisations for infection up to the end of March 2016 in 460,418 middle-aged adults enrolled in the UK Biobank (mean age = 56.23 ± 8.11 years, 53.5% female). Cox regression was used to assess associations between depression and subsequent hospitalisations for any infections, as well as infection subtypes, viral infections, and bacterial infections. Amongst those with depression, we also examined the role of depression duration, the age of onset, and the use of antidepressants in hospitalisation risk. RESULTS: Depression at baseline was prospectively associated with an increased risk of hospitalisation for infection (adjusted hazard ration (aHR) = 1.20, 95% confidence interval (CI) = 1.16 to 1.25). This association was found for all infection subtypes apart from infections of the central nervous system (p = 0.911) and the skin (p = 0.313). Receipt of a depression diagnosis in late adulthood and use of antidepressants (but only in those with none/mild depressive symptoms at baseline) increased the risk of hospitalisation for infection amongst those with depression. CONCLUSIONS: These findings suggest that depression might be a risk factor which could be used to identify those at risk of hospitalisation for infection. Future research is required to understand the underlying factors that might result in this increased risk, so that targeted interventions can be developed. FUNDING: AD and AR are funded by Guy's Charity grant number EIC180702 (MLTC Challenge Fund); AD and JAT are co-funded by MRC and NIHR through grant number MR/S028188/1. IB is supported by the NIHR Maudsley BRC and by the NIHR Collaboration for Leadership in Applied Health Research and Care South Londnoo at King's College Hospital NHS Foundation Trust, King's College London. The views expressed are those of the author[s] and not necessarily those of the ESRC, NIHR, the Department of Health and Social Care or King's College London.

Using Structural Equation Modelling in Routine Clinical Data on Diabetes and Depression: Observational Cohort Study.

BACKGROUND: Large data sets comprising routine clinical data are becoming increasingly available for use in health research. These data sets contain many clinical variables that might not lend themselves to use in research. Structural equation modelling (SEM) is a statistical technique that might allow for the creation of "research-friendly" clinical constructs from these routine clinical variables and therefore could be an appropriate analytic method to apply more widely to routine clinical data. OBJECTIVE: SEM was applied to a large data set of routine clinical data developed in East London to model well-established clinical associations. Depression is common among patients with type 2 diabetes, and is associated with poor diabetic control, increased diabetic complications, increased health service utilization, and increased health care costs. Evidence from trial data suggests that integrating psychological treatment into diabetes care can improve health status and reduce costs. Attempting to model these known associations using SEM will test the utility of this technique in routine clinical data sets. METHODS: Data were cleaned extensively prior to analysis. SEM was used to investigate associations between depression, diabetic control, diabetic care, mental health treatment, and Accident & Emergency (A&E) use in patients with type 2 diabetes. The creation of the latent variables and the direction of association between latent variables in the model was based upon established clinical knowledge. RESULTS: The results provided partial support for the application of SEM to routine clinical data. Overall, 19% (3106/16,353) of patients with type 2 diabetes had received a diagnosis of depression. In line with known clinical associations, depression was associated with worse diabetic control (ß=.034, P<.001) and increased A&E use (ß=.071, P<.001). However, contrary to expectation, worse diabetic control was associated with lower A&E use (ß=-.055, P<.001) and receipt of mental health treatment did not impact upon diabetic control (P=.39). Receipt of diabetes care was associated with better diabetic control (ß=-.072, P<.001), having depression (ß=.018, P=.007), and receiving mental health treatment (ß=.046, P<.001), which might suggest that comprehensive integrated care packages are being delivered in East London. CONCLUSIONS: Some established clinical associations were successfully modelled in a sample of patients with type 2 diabetes in a way that made clinical sense, providing partial evidence for the utility of SEM in routine clinical data. Several issues relating to data quality emerged. Data improvement would have likely enhanced the utility of SEM in this data set.

Prospective associations between vitamin D and depression in middle-aged adults: findings from the UK Biobank cohort.

BACKGROUND: A possible role of vitamin D in the pathophysiology of depression is currently speculative, with more rigorous research needed to assess this association in large adult populations. The current study assesses prospective associations between vitamin D status and depression in middle-aged adults enrolled in the UK Biobank. METHODS: We assessed prospective associations between vitamin D status at the baseline assessment (2006-2010) and depression measured at the follow-up assessment (2016) in 139 128 adults registered with the UK Biobank. RESULTS: Amongst participants with no depression at baseline (n = 127 244), logistic regression revealed that those with vitamin D insufficiency [adjusted odds ratio (aOR) = 1.14, 95% confidence interval (CI) = 1.07-1.22] and those with vitamin D deficiency (aOR = 1.24, 95% CI 1.13-1.36) were more likely to develop new-onset depression at follow-up compared with those with optimal vitamin D levels after adjustment for a wide range of relevant covariates. Similar prospective associations were reported for those with depression at baseline (n = 11 884) (insufficiency: aOR = 1.11, 95% CI 1.00-1.23; deficiency: aOR = 1.30, 95% CI 1.13-1.50). CONCLUSIONS: The prospective associations found between vitamin D status and depression suggest that both vitamin D deficiency and insufficiency might be risk factors for the development of new-onset depression in middle-aged adults. Moreover, vitamin D deficiency (and to a lesser extent insufficiency) might be a predictor of sustained depressive symptoms in those who are already depressed. Vitamin D deficiency and insufficiency is very common, meaning that these findings have significant implications for public health.

Depressive symptoms during early adulthood and the development of physical multimorbidity in the UK: an observational cohort study.

BACKGROUND: An understanding of whether early-life depression is associated with physical multimorbidity could be instrumental for the development of preventive measures and the integrated management of depression. We therefore aimed to map out the cumulative incidence of physical multimorbidity over adulthood, and to determine the association between the presence of depressive symptoms during early adulthood and the development of physical multimorbidity in middle age. METHODS: In this observational cohort study, we used pooled data from the 1958 National Child Development Study (NCDS) and the 1970 British Cohort Study (BCS). Cohort waves were pooled in each decade of adult life available (when cohort members were aged 26 years in the BCS and 23 years in the NCDS [baseline]; 34 years in the BCS and 33 years in the NCDS [age 34 BCS/33 NCDS]; 42 years in the BCS and NCDS [age 42 BCS/NCDS]; and 46 years in the BCS and 50 years in the NCDS [age 46 BCS/50 NCDS]). We included participants who had completed the nine-item Malaise Inventory at baseline, and did not have a history of physical multimorbidity, any physical multimorbidity at baseline, or the presence of depressive symptoms before the development of physical multimorbidity. The presence of depressive symptoms was determined using the nine-item Malaise Inventory (cutoff score ≥4). Physical multimorbidity was defined as having at least two measures of any of the following ten self-reported groups of long-term conditions: asthma or bronchitis; backache; bladder or kidney conditions; cancer; cardiovascular conditions; convulsions or epilepsy; diabetes; hearing conditions; migraine; and stomach, bowel, or gall conditions. Cumulative incidence (with 95% CI) of physical multimorbidity was calculated for each decade considered after baseline, with physical multimorbidity being assessed as both a dichotomous and categorical variable. The association between depressive symptoms and the development of physical multimorbidity was assessed using adjusted relative risk ratios (with 95% CIs). FINDINGS: Analyses included 15 845 participants, of whom 4001 (25·25%; 95% CI 24·57-25·93) had depressive symptoms at baseline and 11 844 (74·75%; 74·07-75·42) did not. The cumulative incidence of physical multimorbidity (dichotomous) ranged over the study period from 2263 (18·44%; 95% CI 17·75-18·14) of 12 273 participants at age 34 BCS/33 NCDS, to 4496 (42·90%; 41·95-43·85) of 10 481 participants at age 46 BCS/50 NCDS, and was consistently higher in participants with depressive symptoms at baseline. The adjusted relative risk of physical multimorbidity was higher in participants with depressive symptoms than in those without and remained stable over the study period (adjusted relative rate ratio 1·67, 95% CI 1·50-1·87, at age 34 BCS/33 NCDS; 1·63, 1·48-1·79, at age 42 BCS/NCDS; and 1·58, 1·43-1·73, at age 46 BCS/50 NCDS). INTERPRETATION: The presence of depressive symptoms during early adulthood is associated with an increased risk of the development of physical multimorbidity in middle age. Although further research about the drivers of this relationship is needed, these results could help to enhance the integrated management of individuals with depressive symptoms and the development of preventive strategies to reduce the effect and burden of physical multimorbidity. FUNDING: UK Medical Research Council and Guy's Charity.