Objective: Both stress-related exhaustion and depression have previously been associated with a decline in cognitive performance, but there is a lack of evidence on whether these conditions have different associations with different cognitive domains and whether they have additive effects on cognitive performance. Furthermore, very little is known about the cognitive effects of chronic stress-related exhaustion. Consequently, the aims of this study were to 1) examine the associations between current stress-related exhaustion and cognitive performance, 2) investigate whether different developmental trajectories of stress-related exhaustion are differently associated with cognitive performance, 3) compare the association between stress-related exhaustion and cognitive performance to the relationship between depressive symptoms and cognitive performance, 4) examine if individuals with comorbid stress-related exhaustion and depression have lower cognitive performance than individuals with at most one of these conditions (i.e., whether clinical stress-related exhaustion and clinical depression might have additive effects on cognitive performance). Methods: The data used in the study was a Finnish population-based sample of six cohorts born between 1962 and 1977 from the Cardiovascular Risk in Young Finns Study. Stress-related exhaustion was assessed using the Maastricht Questionnaire, depressive symptoms with the Beck Depression Inventory, and cognitive performance with four subtests of the Cambridge Neuropsychological Test Automated Battery, measuring visuospatial associative learning, reaction time, sustained attention, and executive functions. Cognitive performance and depressive symptoms were assessed in 2012, and stress-related exhaustion in 2001, 2007, and 2012. Participants were 35 to 50 years old in 2012. Linear associations between stress-related exhaustion and cognitive performance (N = 905) and depressive symptoms and cognitive performance (N = 904) were examined by conducting multivariate regression analyses. Age, sex, socioeconomic status, and parents’ socioeconomic status were controlled in the regression models. Additionally, multivariate analyses of variance were performed to investigate the different developmental trajectories of stress-related exhaustion and their relation to cognitive performance (N = 541) and the associations of comorbid stress-related exhaustion and depression with cognitive performance (N = 1273). Results and conclusion: The main finding was that high stress-related exhaustion is associated with slower reaction times, but not with performance in spatial working memory, visuospatial associative learning, or executive functions. Ongoing, chronic stress-related exhaustion was more strongly associated with slower reaction times than short-term exhaustion experienced years ago. Compared to depressive symptoms, high stress-related exhaustion was associated with slower reaction times also when subclinical cases were included, whereas only clinical levels of depressive symptoms had an association with slower reaction times. There were no differences in cognitive performance between individuals with only stress-related exhaustion or depression and those with comorbid stress-related exhaustion and depression, which supports the notion that these conditions do not have additive effects on cognitive performance. These findings add to the existing evidence of the cognitive effects of stress-related exhaustion in the general population and have several practical implications. Further research is needed on the topic, preferably with longitudinal designs, more comprehensive cognitive measures, and clinical assessment of the psychiatric symptoms.

Studies on the intergenerational transmission of depressive symptoms form a long research tradition. Numerous studies have indicated that children of depressed mothers face an up to 3-fold risk of exhibiting depressive symptoms later in life compared with those children whose mother has not had depressive symptoms. Later studies have observed that paternal depressive symptoms pose an almost equal risk factor particularly for boys. After having established the association between parental and offspring depressive symptoms, research has focused on exploring the mechanisms underlying the transmission of risk. These are also the principal point of interest in the present thesis that gives particular weight to the role of gender, socioeconomic circumstances (parental education and household income) and timing of exposure, belonging to often-hypothesized but seldom-examined shapers of the transmission of risk. Besides these, the study sheds light on the significance of gender of which previous research has produced mixed results. The interpretation of the results leans on the conceptual framework of life course epidemiology, which understands the development of a disease or a disorder as the outcome of biological, psychosocial, and environmental processes that entangle with each other throughout the life course. The study utilized the register-based EKSY014 data set that contains a 20% random sample of all Finnish households with at least one child aged 0-14 years at the end of 2000. Information on the purchases of prescription medicines and visits to inpatient and outpatient care were used as proxy for the incidence of depressive symptoms. Cox proportional hazards regression model, which belongs to the field of survival analysis, was used to compare the event rates between the groups of interest. Exposure to depression of biological parents was measured when persons were 9-14 years old, and the follow-up of an individual’s own depressive symptoms started on the first day of the year the person turned 15 and ended on the last day of the year the person turned 20. Altogether, the principal study population included more than 130,000 persons born between 1986 and 1996. A smaller sub-sample was used to study the effects of an early-life exposure at age 0-5 years and recurrent parental depressive symptoms. According to the analysis, exposure to maternal depressive symptoms at age 9-14 years poses an equally large 2-fold risk for boys and girls. Paternal depressive symptoms put boys at an equal risk as maternal depressive symptoms, but for girls, they pose a smaller 1.5-fold risk. Among those persons who are living with their biological parents, controlling for the effects of socioeconomic factors weakens the association only little and no differences are seen in the risk of intergenerational transmission across the groups of socioeconomic status. Exposure to both maternal depressive symptoms and paternal depressive symptoms poses a bigger risk than a single exposure among both girls and boys. The analysis conducted with the smaller sub-sample implies that an exposure at age 9-14 years poses a bigger risk than an exposure at age 0-5 years. Recurrent exposure to maternal depressive symptoms appears to be a particularly severe risk factor. The results of the study support the life course epidemiological processes of accumulation of risk and chains of risk: Exposure to depressive symptoms in both parents and the long-term chaining of parental depressive symptoms put the person at the greatest risk. Parental depressive symptoms and socioeconomic status appear as largely independent risk factors of adolescent depressive symptoms; thus, those adolescents having a low socioeconomic status and a history of parental depressive symptoms face a particularly elevated risk of exhibiting depressive symptoms. The preliminary analysis did not give support to the assumed sensitive period in the first years of life, but the question should be examined further with a larger sample. Overall, the results advocate a more holistic approach to the prevention of adolescent depressive symptoms, beginning from the identification of familial risk and leading to actions that target all members of the family.

Objective Depression and high blood pressure are becoming more common problems, but their relation remains unclear. This master's thesis studied the relation between depression and high blood pressure in the longitudinal Young Finns Study over a follow-up of four years. The aim was to examine whether 1) baseline depressive symptoms predict blood pressure over the follow-up, 2) the relation between depression and blood pressure differs among men and women, 3) health choices affect the relation, and 4) there is a relation between the duration of depression and blood pressure. Methods The participants (N=909) were about 42 years old, and 61 % of them were women. Their blood pressure and BDI-II depression scores were measured in 2007 ja 2011. Three-step regression analysis was used to predict the systolic and diastolic blood pressure based on the baseline depression score. The first model was controlled for age, gender and baseline blood pressure, the second model also for education and income, and the third model additionally for health choices. The average blood pressures of non-depressed, once depressed and twice depressed participants were compared in analysis of variance. The group comparisons were additionally controlled for age, gender and baseline blood pressure in analysis of covariance. Results and conclusions Baseline depressive symptoms did not predict blood pressure. Among women, a positive relation between depression and blood pressure was found in the first model, but not in the more controlled models. The relation between depression and blood pressure was partly explained by health choices; higher body mass index predicted higher blood pressure. Controlling for age, gender and baseline blood pressure, the duration of depression was connected to higher blood pressure; the diastolic blood pressure was higher, when the participant was depressed both in the beginning and end of the follow-up.

Objectives The modified Telephone Interview for Cognitive Status (TICS-m) is an efficient and cost-effective screening instrument of dementia, but there is less support for its utility in the detection of mild cognitive impairment (MCI). We undertook a comprehensive evaluation of the utility of different TICS-m versions with or without an education-adjusted scoring method to classify dementia and MCI in a large population-based sample. Methods Cross-sectional assessment of cognition (TICS-m), depressive symptoms (CES-D), and apolipoprotein E (APOE) epsilon 4 status was performed on 1772 older adults (aged 71-78 y, education 5-16 y, 50% female) from the population-based older Finnish Twin Cohort. TICS-m classification methods with and without education adjustment were used to classify individuals with normal cognition, MCI, or dementia. Results The prevalence of dementia and MCI varied between education-adjusted (dementia = 3.7%, MCI = 9.3%) and unadjusted classifications (dementia = 8.5%-11%, MCI = 22.3%-41.3%). APOE epsilon 4 status was associated with dementia irrespective of education adjustment, but with MCI only when education adjustment was used. Regardless of the version, poorer continuous TICS-m scores were associated with higher age, lower education, more depressive symptoms, male sex, and being an APOE epsilon 4 carrier. Conclusions We showed that demographic factors, APOE epsilon 4 status, and depressive symptoms were similarly related to continuous TICS-m scores and dementia classifications with different versions. However, education-adjusted classification resulted in a lower prevalence of dementia and MCI and in a higher proportion of APOE epsilon 4 allele carriers among those identified as having MCI. Our results support the use of education-adjusted classification especially in the context of MCI.

An increasing number of studies have addressed how adolescents’ social media use is associated with depressive symptoms. However, few studies have examined whether these links occur longitudinally across adolescence when examined at the individual level of development. This study investigated the within-person effects between active social media use and depressive symptoms using a five-wave longitudinal dataset gathered from 2891 Finnish adolescents (42.7% male, age range 13–19 years). Sensitivity analysis was conducted, adjusting for gender and family financial status. The results indicate that depressive symptoms predicted small increases in active social media use during both early and late adolescence, whereas no evidence of the reverse relationship was found. Yet, the associations were very small, statistically weak, and somewhat inconsistent over time. The results provide support for the growing notion that the previously reported direct links between social media use and depressive symptoms might be exaggerated. Based on these findings, we suggest that the impact of social media on adolescents’ well-being should be approached through methodological assumptions that focus on individual-level development.

Objective: To examine health service (HS) utilization profiles among a non-depressive population and patients with depressive symptoms (DS) with and without clinical depression. Design, subjects and setting: The study population was based on primary care patients with DS scoring >= 10 in the 21-item Beck Depression Inventory (BDI) and who were at least 35 years old and had been referred to depression nurse case managers (n = 705). Their psychiatric diagnosis was confirmed with the Mini-International Neuropsychiatric Interview (M.I.N.I.). Of these patients, 447 had clinical depression. The number of patients with DS without clinical depression was 258. The control group consisted of a random sample of 414 residents with a BDI score <10. Use of HS (visits and phone calls to a doctor and a nurse) was based on patient records. Main outcome measures: Number of visits and calls to physicians and nurses. Results: Patients with DS regardless of their depression diagnosis used primary health care (PHC) services three times more than the controls (p <0.001). In the secondary care, the differences were smaller but significant. Of the controls, 70% had 0-4 HS contacts per year whereas a majority of the patients having DS had more than 5 contacts per year. The number of contacts correlated with the BDI from a score of 0 to 10 but not as clearly in the higher scores. Conclusion: Depressive symptoms, both with or without clinical depression, are associated with increased HS use, especially in PHC. This study suggests that even mild depressive symptoms are associated with an increased use of HS.