Enhancing the accuracy of register-based metrics: Comparing methods for handling overlapping psychiatric register entries in Finnish healthcare registers.

OBJECTIVES: Healthcare registers are invaluable resources for research. Partly overlapping register entries and preliminary diagnoses may introduce bias. We compare various methods to address this issue and provide fully reproducible open-source R scripts. METHODS: We used all Finnish healthcare registers 1969-2020, including inpatient, outpatient and primary care. Four distinct models were formulated based on previous reports to identify actual admissions, discharges, and discharge diagnoses. We calculated the annual number of treatment events and patients, and the median length of hospital stay (LOS). We compared these metrics to non-processed data. Additionally, we analyzed the lifetime number of individuals with registered mental disorders. RESULTS: Overall, 2,130,468 individuals had a registered medical contact related to mental disorders. After processing, the annual number of inpatient episodes decreased by 5.85%-10.87% and LOS increased by up to 3 days (27.27%) in years 2011-2020. The number of individuals with lifetime diagnoses reduced by more than 1 percent point (pp) in two categories: schizophrenia spectrum (3.69-3.81pp) and organic mental disorders (1.2-1.27pp). CONCLUSIONS: The methods employed in pre-processing register data significantly impact the number of inpatient episodes and LOS. Regarding lifetime incidence of mental disorders, schizophrenia spectrum disorders require a particular focus on data pre-processing.

Transmission of Mental Disorders in Adolescent Peer Networks.

Importance: Previous research indicates that mental disorders may be transmitted from one individual to another within social networks. However, there is a lack of population-based epidemiologic evidence that pertains to the full range of mental disorders. Objective: To examine whether having classmates with a mental disorder diagnosis in the ninth grade of comprehensive school is associated with later risk of being diagnosed with a mental disorder. Design, Setting, and Participants: In a population-based registry study, data on all Finnish citizens born between January 1, 1985, and December 31, 1997, whose demographic, health, and school information were linked from nationwide registers were included. Cohort members were followed up from August 1 in the year they completed ninth grade (approximately aged 16 years) until a diagnosis of mental disorder, emigration, death, or December 31, 2019, whichever occurred first. Data analysis was performed from May 15, 2023, to February 8, 2024. Exposure: The exposure was 1 or more individuals diagnosed with a mental disorder in the same school class in the ninth grade. Main Outcomes and Measures: Being diagnosed with a mental disorder during follow-up. Results: Among the 713 809 cohort members (median age at the start of follow-up, 16.1 [IQR, 15.9-16.4] years; 50.4% were males), 47 433 had a mental disorder diagnosis by the ninth grade. Of the remaining 666 376 cohort members, 167 227 persons (25.1%) received a mental disorder diagnosis during follow-up (7.3 million person-years). A dose-response association was found, with no significant increase in later risk of 1 diagnosed classmate (HR, 1.01; 95% CI, 1.00-1.02), but a 5% increase with more than 1 diagnosed classmate (HR, 1.05; 95% CI, 1.04-1.06). The risk was not proportional over time but was highest during the first year of follow-up, showing a 9% increase for 1 diagnosed classmate (HR, 1.09; 95% CI, 1.04-1.14), and an 18% increase for more than 1 diagnosed classmate (HR, 1.18; 95% CI, 1.13-1.24). Of the examined mental disorders, the risk was greatest for mood, anxiety, and eating disorders. Increased risk was observed after adjusting for an array of parental, school-level, and area-level confounders. Conclusions and Relevance: The findings of this study suggest that mental disorders might be transmitted within adolescent peer networks. More research is required to elucidate the mechanisms underlying the possible transmission of mental disorders.

Intergenerational continuity of loneliness and potential mechanisms: Young Finns Multigenerational Study.

Evidence on the intergenerational continuity of loneliness and on potential mechanisms that connect loneliness across successive generations is limited. We examined the association between loneliness of (G0) parents (859 mothers and 570 fathers, mean age 74 years) and their children (G1) (433 sons and 558 daughters, mean age 47 years) producing 991 parent-offspring pairs and tested whether these associations were mediated through subjective socioeconomic position, temperament characteristics, cognitive performance, and depressive symptoms. Mean loneliness across parents had an independent effect on their adult children's experienced loneliness (OR = 1.72, 95% CI 1.23-2.42). We also found a robust effect of mothers' (OR = 1.64, 95% CI 1.17-2.29), but not of fathers' loneliness (OR = 1.47, 95% CI 0.96-2.25) on offspring's experienced loneliness in adulthood. The associations were partly mediated by offspring depressive (41-54%) and anxiety (29-31%) symptoms. The current findings emphasize the high interdependence of loneliness within families mediated partly by offspring's mental health problems.

Which predicts longevity better: Satisfaction with life or purpose in life?

Life satisfaction and purpose in life are fundamental yet separate ways to evaluate one's life. Both positively predict physical health and longevity, making them key factors for length and quality of life. However, we do not know which of them predicts mortality, when controlling for the influence of each other. Given that purpose in life involves a more active engagement with life and can help to cope with suffering, we hypothesize that purpose in life could be a more direct prospective predictor of longevity, overshadowing any effect of life satisfaction, when the two are pitted against each other as prospective predictors of longevity. To examine these hypotheses, we utilized Midlife in the U.S. survey, which is a 23-year follow-up study, (N = 5,993) and Cox proportional hazards models, repeating the analyses both without covariates and when controlling for various demographic and health-related variables. We show that both life satisfaction and purpose in life predict mortality when modeled separately. When life satisfaction, purpose in life and self-rated health were entered as simultaneous predictors of mortality, purpose in life remained a slightly more robust predictor of mortality, while life satisfaction became only marginally significant, suggesting that some of the factors that connect it to mortality are covered by the other two subjective evaluations. Overall, the results demonstrate that purpose in life is a robust predictor of mortality, and thus a key dimension of well-being to attend to as people age, while the predictive power of life satisfaction is more dependent on the choice of covariates. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Variations in Suicide Risk and Risk Factors After Hospitalization for Depression in Finland, 1996-2017.

Importance: Although incidence of suicide in depression varies remarkably temporally, risk factors have been modeled as constant and remain uncharted in the short term. How effectively factors measured at one point in time predict risk at different time points is unknown. Objective: To examine the absolute risk and risk factors for suicide in hospitalized patients with depression starting from the first days after discharge up to 2 years and to evaluate whether the size of relative risk by factor displays temporal patterns over consecutive phases of follow-up. Design, Setting, and Participants: This population-based study using Finnish registers (hospital discharge, population, and cause of death registers) included all hospitalizations for depression as the principal diagnosis in Finland from 1996 to 2017, with a maximum follow-up of 2 years. Data were analyzed from January 2022 to November 2023. Main Outcomes and Measures: Incidence rate (IR), IR ratios, hazard functions, and hazard ratios for suicide by consecutive time periods (0 to 3 days, 4 to 7 days, 7 to 30 days, 31 to 90 days, 91 to 365 days, and 1 to 2 years) since discharge. Results: This study included 193 197 hospitalizations among 91 161 individuals, of whom 51 197 (56.2%) were female, and the mean (SD) age was 44.0 (17.3) years. Altogether, patients were followed up to 226 615 person-years. A total of 1219 men and 757 women died of suicide. Incidence of suicide was extremely high during the first days after discharge (IR of 6062 [95% CI, 4963-7404] per 100 000 on days 0 to 3; IR of 3884 [95% CI, 3119-4835] per 100 000 on days 4 to 7) and declined thereafter. Several factors were associated with risk of suicide over the first days after discharge. Current suicide attempt by hanging or firearms increased the risk of suicide most on days 0 to 3 (IR ratio, 18.9; 95% CI, 3.1-59.8) and on days 0 to 7 (IR ratio, 10.1; 95% CI, 1.7-31.5). Temporal patterns of the size of the relative risk diverged over time, being constant, declining, or increasing. Clinical factors had the strongest association immediately. Relative risk remained constant among men and even increased among those with alcohol or substance use disorder. Conclusions and Relevance: In this study, patients hospitalized for depression had extremely high risk of suicide during the first days after discharge. Thereafter, incidence declined steeply but remained high. Within the periods of the highest risk of suicide, several factors increased overall risk manyfold. Risk factors' observed potencies varied over time and had characteristic temporal patterns.

Association of antidepressant and benzodiazepine use, and anticholinergic burden with cognitive performance in schizophrenia.

Schizophrenia is characterized by cognitive impairment affecting everyday functioning. Earlier research has hypothesized that antidepressants may associate with better cognitive functioning, but results are mixed. This study explored the association between antidepressant use and cognitive performance in terms of reaction time and visual learning in a clinical sample. In addition, we examined benzodiazepine use and anticholinergic burden. Study participants were drawn from the SUPER-Finland cohort, collected among patients with psychotic illnesses in 2016-2018 throughout Finland (n = 10,410). The analysis included adults with a schizophrenia diagnosis (F20) and results from a cognitive assessment (n = 3365). Information about medications and psychosocial factors were gathered through questionnaire and interview. Cognitive performance was assessed with the Cambridge Neuropsychological Test Automated Battery (CANTAB) with two subtests measuring reaction time and visual learning. Almost 36 % of participants used at least one antidepressant. The use of antidepressants in general was not associated with performance in the reaction time and visual learning tasks. However, the use of SNRI antidepressants was associated with a faster reaction time. Benzodiazepine use and a higher anticholinergic burden were associated with poorer performance in both tests. The results strengthen earlier findings that there is no association between antidepressant use in general and cognitive performance in schizophrenia. However, the association of SNRI medications with a faster reaction time warrants further research. Moreover, the results suggest that more attention should be paid to the anticholinergic burden of the medications used by patients with schizophrenia, as well as avoiding continuous benzodiazepine use.

Geographical variation in treated psychotic and other mental disorders in Finland by region and urbanicity.

PURPOSE: In Finland, prevalence of schizophrenia is higher in the eastern and northern regions and co-occurs with the distribution of schizophrenia polygenic risk scores. Both genetic and environmental factors have been hypothesized to contribute to this variation. We aimed to examine the prevalence of psychotic and other mental disorders by region and degree of urbanicity, and the impacts of socio-economic adjustments on these associations. METHODS: Nationwide population registers from 2011 to 2017 and healthcare registers from 1975 to 2017. We used 19 administrative and three aggregate regions based on the distribution of schizophrenia polygenic risk scores, and a seven-level urban-rural classification. Prevalence ratios (PRs) were calculated by Poisson regression models and adjusted for gender, age, and calendar year (basic adjustments), and Finnish origin, residential history, urbanicity, household income, economic activity, and physical comorbidity (additional adjustments) on an individual level. Average marginal effects were used to visualize interaction effects between region and urbanicity. RESULTS: A total of 5,898,180 individuals were observed. All mental disorders were slightly more prevalent (PR 1.03 [95% CI, 1.02-1.03]), and psychotic disorders (1.11 [1.10-1.12]) and schizophrenia (1.19 [1.17-1.21]) considerably more prevalent in eastern and northern than in western coastal regions. After the additional adjustments, however, the PRs were 0.95 (0.95-0.96), 1.00 (0.99-1.01), and 1.03 (1.02-1.04), respectively. Urban residence was associated with increased prevalence of psychotic disorders across all regions (adjusted PR 1.21 [1.20-1.22]). CONCLUSION: After adjusting for socioeconomic and sociodemographic factors, the within-country distribution of mental disorders no longer followed the traditional east-west gradient. Urban-rural differences, on the other hand, persisted after the adjustments.

Loneliness and cognitive function in older adults: Longitudinal analysis in 15 countries.

This study aims to evaluate the directionality of the association between loneliness and cognitive performance in older adults, accounting for confounding factors. Data were from 55,662 adults aged ≥ 50 years who participated in Waves 5-8 of the Survey of Health, Ageing and Retirement in Europe (SHARE). Loneliness was assessed with the Three-Item Loneliness Scale (TILS) and with a one-item direct question. Cognitive performance was assessed with four measures: verbal fluency, numeracy, immediate recall, and delayed recall. Age, sex, geographical area, educational attainment, partnership status, depressive symptoms, and previous chronic diseases at baseline were used as covariates. We analyzed the associations with three-wave random intercept cross-lagged panel models (RI-CLPM) and conducted age-stratified analysis among those younger versus older than 65 years. Full information maximum likelihood estimators were used to handle missing values in Waves 6-8 in the main analyses. We also conducted additional sensitivity analyses stratified by retirement status (retired vs. not) at baseline. At the within-person level, loneliness and cognitive performance were not associated with each other among those aged 50-64 years in the main time-lagged analysis. Among those aged ≥ 65 years, loneliness was associated with lower cognitive performance in the next wave in all four cognitive domains. In addition, lower verbal fluency predicted greater loneliness in the next waves among this age group. Similar patterns were found independently of retirement status at baseline. These results suggest that loneliness is a psychosocial risk factor for cognitive decline among older adults (≥ 65 years). (PsycInfo Database Record (c) 2023 APA, all rights reserved).

School achievement in adolescence and the risk of mental disorders in early adulthood: a Finnish nationwide register study.

School grades in adolescence have been linked to later psychiatric outcomes, but large-scale nationwide studies across the spectrum of mental disorders are scarce. In the present study, we examined the risk of a wide array of mental disorders in adulthood, as well as the risk of comorbidity, associated with school achievement in adolescence. We used population-based cohort data comprising all individuals born in Finland over the period 1980-2000 (N = 1,070,880) who were followed from age 15 or 16 until a diagnosis of mental disorder, emigration, death, or December 2017, whichever came first. Final grade average from comprehensive school was the exposure, and the first diagnosed mental disorder in a secondary healthcare setting was the outcome. The risks were assessed with Cox proportional hazards models, stratified Cox proportional hazard models within strata of full-siblings, and multinomial regression models. The cumulative incidence of mental disorders was estimated using competing risks regression. Better school achievement was associated with a smaller risk of all subsequent mental disorders and comorbidity, except for eating disorders, where better school achievement was associated with a higher risk. The largest associations were observed between school achievement and substance use disorders. Overall, individuals with school achievement more than two standard deviations below average had an absolute risk of 39.6% of a later mental disorder diagnosis. By contrast, for individuals with school achievement more than two standard deviations above average, the absolute risk of a later mental disorder diagnosis was 15.7%. The results show that the largest mental health burden accumulates among those with the poorest school achievement in adolescence.

Socioeconomic position at the age of 30 and the later risk of a mental disorder: a nationwide population-based register study.

BACKGROUND: A study was undertaken to examine the association between multiple indicators of socioeconomic position (SEP) at the age of 30 and the subsequent risk of the most common mental disorders. METHODS: All persons born in Finland between 1966 and 1986 who were alive and living in Finland at the end of the year when they turned 30 were included. Educational attainment, employment status and personal total income were used as the alternative measures of SEP. Cox proportional hazards models were used to examine the association of SEP at the age of 30 with later risk of mental disorders. Additional analyses were conducted using a sibling design to account for otherwise unobserved shared family characteristics. Competing risks models were used to estimate absolute risks. RESULTS: The study population included 1 268 768 persons, 26% of whom were later diagnosed with a mental disorder. Lower SEP at age 30 was consistently associated with a higher risk of being later diagnosed with a mental disorder, even after accounting for shared family characteristics and prior history of a mental disorder. Diagnosis-specific analyses showed that the associations were considerably stronger when substance misuse or schizophrenia spectrum disorders were used as an outcome. Absolute risk analyses showed that, by the age of 52 years, 58% of persons who had low educational attainment at the age of 30 were later diagnosed with a mental disorder. CONCLUSIONS: Poor SEP at the age of 30 is associated with an increased risk of being later diagnosed with a mental disorder.

Association of social isolation and loneliness with risk of incident hospital-treated infections: an analysis of data from the UK Biobank and Finnish Health and Social Support studies.

BACKGROUND: Although loneliness and social isolation have been linked to an increased risk of non-communicable diseases such as cardiovascular disease and dementia, their association with the risk of severe infection is uncertain. We aimed to examine the associations between loneliness and social isolation and the risk of hospital-treated infections using data from two independent cohort studies. METHODS: We assessed the association between loneliness and social isolation and incident hospital-treated infections using data for participants from the UK Biobank study aged 38-73 years at baseline and participants from the nationwide population-based Finnish Health and Social Support (HeSSup) study aged 20-54 years at baseline. For inclusion in the study, participants had to be linked to national health registries, have no history of hospital-treated infections at or before baseline, and have complete data on loneliness or social isolation. Participants with missing data on hospital-treated infections, loneliness, and social isolation were excluded from both cohorts. The outcome was defined as a hospital admission with a primary diagnosis of infection, ascertained via linkage to electronic health records. FINDINGS: After exclusion of 8·6 million participants for not responding or not providing appropriate consent, the UK Biobank cohort consisted of 456 905 participants (249 586 women and 207 319 men). 26 860 (6·2%) of 436 001 participants with available data were reported as being lonely and 40 428 (9·0%) of 448 114 participants with available data were socially isolated. During a median 8·9 years (IQR 8·0-9·6) of follow-up, 51 361 participants were admitted to hospital due to an infectious disease. After adjustment for age, sex, demographic and lifestyle factors, and morbidities, loneliness was associated with an increased risk of a hospital-treated infection (hazard ratio [HR] 1·12 [95% CI 1·07-1·16]), whereas social isolation was not (HR 1·01 [95% CI 0·97-1·04]). Of 64 797 individuals in the HeSSup cohort, 18 468 (11 367 women and 7101 men) were eligible for inclusion. 4466 (24·4%) of 18 296 were lonely and 1776 (9·7%) of 18 376 socially isolated. During a median follow-up of 10·0 years (IQR 10·0-10·1), 814 (4·4%) participants were admitted to hospital for an infectious disease. The HRs for the HeSSup study replicated those in the UK Biobank (multivariable-adjusted HR for loneliness 1·32 [95% CI 1·06-1·64]; 1·08 [0·87-1·35] for social isolation). INTERPRETATION: Loneliness might increase susceptibility to severe infections, although the magnitude of this effect appears modest and residual confounding cannot be excluded. Interventional studies are required before policy recommendations can advance. FUNDING: Academy of Finland, the UK Medical Research Council, and Wellcome Trust UK.

Association between depression and the likelihood of having children: a nationwide register study in Finland.

BACKGROUND: Depression may be associated with a lower likelihood of having children, but the findings are inconsistent. Previous population-based studies on this topic are limited. OBJECTIVE: We examined associations between depression and the likelihood of having children, the number of children, and the parental age at first birth. We also evaluated whether these associations differ for people with low, middle, and high educational levels. STUDY DESIGN: We conducted a nationwide register cohort study including all individuals born in Finland from 1960 to 1980 (n=1,408,951). Depression diagnoses were identified from the Care Register for Health Care (containing records of inpatient hospital episodes for the period 1969 to 2017 and of specialist outpatient visits for the period 1996 to 2017). The main outcomes-having biological children, the number of biological children, and the parental age at first birth-were identified from the Population Register of Statistics Finland and were defined either in the last year of the follow-up in 2017 or the last year alive or living in Finland. The association between depression and the likelihood of having children was examined using a logistic regression analysis; the association between depression and the number of children was evaluated using Poisson regression analyses, and the association between depression and the age at first birth was evaluated using a linear regression analysis. All analyses were conducted separately for men and women. RESULTS: For both men and women, secondary care-treated depression was associated with a lower likelihood of having children (odds ratio, 0.66; 95% confidence interval, 0.64-0.67 for men; odds ratio, 0.84; 95% confidence interval, 0.82-0.85 for women) and with having fewer children (incidence rate ratio, 0.86; 95% confidence interval, 0.86-0.87 for men; incidence rate ratio, 0.96; 95% confidence interval, 0.96-0.96 for women). Depression was associated with a slightly lower parental age at first birth (33.1 vs 34.0; P<.001 for men; 31.3 vs 32.1; P<.001 for women). Dose-response associations between the severity of depression and a decreased likelihood of having children, as well as having fewer children, were observed. Earlier onset of depression was related to a lower likelihood of having children and to having fewer children. Among men and women in middle- and high-level educational groups, depression was associated with a lower likelihood of having children and with having fewer children. Among men with a low level of education, no associations were observed. Among women with a low level of education, depression was associated with a higher likelihood of having children and with having more children. CONCLUSION: Both men and women with secondary care-treated depression have a lower likelihood of having children and have fewer children. Our findings suggest that depression may be one of the factors that contribute to the likelihood of having children, which should be addressed by policy makers.

The association between mental disorders and subsequent years of working life: a Danish population-based cohort study.

BACKGROUND: Mental disorders can affect workforce participation via a range of mechanisms. In this study, we aimed to estimate the association between different types of mental disorders and working years lost, defined as the number of years not actively working or enrolled in an educational programme. METHODS: In this population-based cohort study, we included all people aged 18-65 years (mean 38·0 [SD 13·9]) in the Danish Civil Registration System from Jan 1, 1995 to Dec 31, 2016. Information on mental disorders was obtained from the Danish Psychiatric Central Research Register and information on labour market characteristics was obtained from administrative registers. Follow-up started at age 18 years, immigration to Denmark, or on Jan 1, 1995, whichever came later; and it ended at age 65 years, death, emigration from Denmark, disability pension, voluntary early retirement, or Dec 31, 2016 (whichever came earlier). As the main outcome, we estimated working years lost for those diagnosed with any mental disorder and 24 types of mental disorders, as well as for the general population of same age and sex. We decomposed total working years lost into periods of unemployment or sick leave, disability pension, voluntary early retirement, or death. Data on ethnicity were not available through administrative registers. FINDINGS: A total of 5 163 321 individuals, 2 642 383 men and 2 520 938 women, were followed up for 65·4 million person-years. Overall, 488 775 (9·47%) individuals were diagnosed with a mental disorder. On average, individuals with mental disorders lost an additional 10·52 (95% CI 10·48-10·57) years of working life compared with the general Danish population. Receiving a disability pension (7·54 [7·49-7·59] years) and longer periods of unemployment (2·24 [2·21-2·27] years) accounted for most of this difference. INTERPRETATION: Our findings foreground the substantial impact of mental disorders on workforce participation. There is a need to invest in programmes that reduce the burden of working years lost and assist people with mental disorders in returning to the workforce. FUNDING: Lundbeck Foundation and Danish National Research Foundation.

Long-term residential sunlight exposure associated with cognitive function among adults residing in Finland.

While sunlight may influence cognitive function through several pathways, associations of residential sunlight exposure with cognitive function are not well known. We evaluated associations of long-term residential sunlight exposure with cognitive function among a representative cohort of 1838 Finnish adults residing in Finland who underwent comprehensive cognitive assessment in midlife. We linked daily recordings of global solar radiation to study participants using residential information and calculated the average daily residential exposure to sunlight for four exposure time intervals: 2 months, 1 year, 2 years and 5 years prior to the date of the cognition assessment. Associations of the residential sunlight exposure with cognitive function were assessed using linear regression analyses adjusting for season, sex, age, and individual- and neighborhood-level socioeconomic characteristics. Greater average residential sunlight exposure over 2 and 5 years prior to the cognitive function assessment was associated with better global cognitive function (b = 0.13, 95% CI = 0.01, 0.25; b = 0.17, 95% CI = 0.05, 0.29, per 1 MJ/m2 difference in sunlight exposure), while no associations with global cognitive function were observed at shorter exposure time intervals. In domain-specific analyses, greater residential exposure to sunlight over 1, 2 and 5 years prior to the cognitive function assessment was associated with better performance on new learning and visual memory (b = 0.10, 95% CI = 0.00, 0.20; b = 0.16, 95% CI = 0.04, 0.28; b = 0.19, 95% CI = 0.08, 0.31) and sustained attention (b = 0.15, 95% CI = 0.05, 0.25; b = 0.18, 95% CI = 0.06, 0.30; b = 0.17, 95% CI = 0.05, 0.29), but worse performance on reaction time (b = - 0.12, 95% CI = - 0.22, - 0.02; b = -0.15, 95% CI = - 0.28, - 0.02; b = - 0.18, 95% CI = - 0.30, - 0.05). Residential sunlight exposure was not associated with executive function. These findings suggest long-term residential sunlight exposure may be an environmental factor influencing cognitive function among a cognitively healthy cohort residing in Northern Europe. Further studies in populations residing in different geographical locations are needed.

Climatic exposures in childhood and the risk of schizophrenia from childhood to early adulthood.

BACKGROUND: Season of birth is a risk factor of schizophrenia, and it is possible that cumulative exposure to climatic factors during childhood affects the risk of schizophrenia. We conducted a cohort study among 365,482 persons born in Finland in 1990-1995 to examine associations of 10-year cumulative exposure to global solar radiation and ambient temperature in childhood with schizophrenia. METHODS: Data on schizophrenia diagnoses and sociodemographic factors from the Finnish population register and health care register were linked to daily meteorological data using residential information. The study population was followed from age 10 until the first schizophrenia diagnosis, death, emigration or December 31, 2017, whichever came first. Hazard ratios (HR) for the risk of schizophrenia were estimated using Cox proportional hazards model. RESULTS: Compared to the lowest quintile of global solar radiation or ambient temperature, growing up in the second highest quintile (Q4) was associated with greater risk of schizophrenia. These hazard ratios were attenuated after adjustment for parental mental disorder, parental education, parental income, area-level socioeconomic characteristics and urbanicity (HR = 1.29, 95 % CI 1.06-1.58 for radiation; HR = 1.24, 95 % CI, 1.02-1.52 for temperature). Continuous linear terms evaluated in secondary models suggested a greater risk of schizophrenia at greater childhood exposure to global radiation and ambient temperature, but these associations did not remain in fully adjusted models. CONCLUSIONS: We found no consistent evidence that cumulative exposure to sunlight and ambient temperature in childhood is associated with the risk of developing schizophrenia. Studies in other populations residing in different latitudes are needed.

A genome-wide association study of total child psychiatric problems scores.

Substantial genetic correlations have been reported across psychiatric disorders and numerous cross-disorder genetic variants have been detected. To identify the genetic variants underlying general psychopathology in childhood, we performed a genome-wide association study using a total psychiatric problem score. We analyzed 6,844,199 common SNPs in 38,418 school-aged children from 20 population-based cohorts participating in the EAGLE consortium. The SNP heritability of total psychiatric problems was 5.4% (SE = 0.01) and two loci reached genome-wide significance: rs10767094 and rs202005905. We also observed an association of SBF2, a gene associated with neuroticism in previous GWAS, with total psychiatric problems. The genetic effects underlying the total score were shared with common psychiatric disorders only (attention-deficit/hyperactivity disorder, anxiety, depression, insomnia) (rG > 0.49), but not with autism or the less common adult disorders (schizophrenia, bipolar disorder, or eating disorders) (rG < 0.01). Importantly, the total psychiatric problem score also showed at least a moderate genetic correlation with intelligence, educational attainment, wellbeing, smoking, and body fat (rG > 0.29). The results suggest that many common genetic variants are associated with childhood psychiatric symptoms and related phenotypes in general instead of with specific symptoms. Further research is needed to establish causality and pleiotropic mechanisms between related traits.

Do the Temperamental Characteristics of Both Mother and Child Influence the Well-Being of Adopted and Non-Adopted Children?

(1) Background: For decades, the temperaments of infants and small children have been a focus of studies in human development and been seen as a potential contributor to children's developmental patterns. However, less is known about the interplay between the temperamental characteristics of mothers and their children in the context of explaining variations in developmental outcomes. The aim of our study was to explore the associations-with or without genetic links-of the temperaments and psychological distress of mothers and the temperaments of children with behavioral problems in a group of internationally adopted children and their adoptive mothers and in a group of non-adopted children and their mothers. (2) Methods: Data (n = 170) were derived from the ongoing Finnish Adoption (FinAdo) follow-up study. The children included were under the age of 7 years; 74 were adopted internationally through legal agencies between October 2010 and December 2016, and the remaining 96 were non-adopted children living with their birth parents (biological group) recruited from day-care centers. We used Mary Rothbart's temperament questionnaires to assess temperament, the Child Behavior Checklist (CBCL) to obtain data on the children's behavioral/emotional problems and competencies, and the General Health Questionnaire (GHQ) to assess parental psychological distress. The study was approved by the Ethics Committee of the Hospital District of Southwest Finland, and written informed consent was obtained from the parents and the children themselves. (3) Results: The negative affectivities of both mothers and children were associated with the total CBCL and with both internalizing and externalizing problem behaviors after adjusting for age, gender, and adoption status. Both relationships remained significant when tested simultaneously, suggesting additive effects. Maternal negative affect was associated with problem behavior irrespective of child extraversion/surgency. Child extraversion/surgency was associated with lower levels of all internalizing behavioral problems when adjusted for maternal sociability. Child negative affect was associated with all behavioral problem measures irrespective of maternal sociability or maternal psychological distress. Maternal distress was associated with child problem behaviors only in children with low extraversion/surgency. (4) Limitations: The sample size was relatively small, and the information was gathered solely with questionnaires. (5) Conclusions: The results of the study may be clinically significant. Child negative affect, maternal negative affect, and maternal experienced distress, combined with low child extraversion/surgency, may increase the risk of child problem behaviors in both adoptees and non-adoptees.

Psychosocial work environment as a dynamic network: a multi-wave cohort study.

While characteristics of psychosocial work environment have traditionally been studied separately, we propose an alternative approach that treats psychosocial factors as interacting elements in networks where they all potentially affect each other. In this network analysis, we used data from a prospective occupational cohort including 10,892 participants (85% women; mean age 47 years) and repeated measurements of seven psychosocial work characteristics (job demands, job control, job uncertainty, team climate, effort-reward imbalance, procedural justice and interactional justice) assessed in 2000, 2004, 2008 and 2012. Results from multilevel longitudinal vector autoregressive models indicated that job demands as well as interactional and procedural justice were most broadly associated with the subsequent perceptions of the work-related psychosocial factors (high out-Strength), suggesting these factors might be potentially efficient targets of workplace interventions. The results also suggest that modifying almost any of the studied psychosocial factors might be relevant to subsequent perceptions of effort-reward imbalance and interactional justice at the workplace.