Aspects of positive and negative mental health in young people, aged 16-29 years : measurements, determinants, and interventions

Abstract: Background: Mental health problems in young people, i.e. those self-reported as well as registered diagnoses, have been of concern for decades. For Western societies, most studies indicate a rise in symptoms, but also in diagnoses of depression, anxiety and stress in younger age groups since the 1990s. The increase follows a pattern of societal changes, namely a prolongation of young people’s years in education, later entry into the labour market with frequently insecure conditions, longerstanding time without own housing and postponed building of partnership and family. A large number of studies focusing on young people’s mental ill health have been carried out, but less attention has been paid to positive mental health (PMH) in the age group of 16-29 years. PMH allows a view where building on strengths, capacity and health promotion is accentuated rather than leaning on deficit models and prevention of mental ill health. A balanced consideration of both aspects of mental health should give a more complete picture of the mental health characteristics in young people. Aim: The overall aim was to identify which potential determinants are associated with or may predict positive and negative mental health (NMH) in the age group of 16-29 years by self-reporting measurements, and to investigate the effectiveness of mental health interventions. Methods: The thesis is built on analyses of two population surveys (Study I and Study II), along with merged data from intervened secondary schools (Study III), and lastly on a systematic review and meta-analysis of mental health interventions for students in tertiary education (Study IV). Specifically, the data-sources and study populations for the specific research questions were as follows. First, we investigated if the 12-item General Health Questionnaire (GHQ-12) had the capacity to measure PMH in addition to NMH. We employed data from the cross-sectional Swedish National Public Health Survey 2004-2009, including 41,668 individuals aged 16-29 years. Additionally, we investigated if the survey’s health and background factors, i.e. potential determinants of mental health, could be related to either PMH or NMH factors (Study I). Second, we examined which potential determinants predict stable mental health, specifically reporting < 3 GHQ-points at all four measurement waves in the population aged 18-29 years compared to older age groups. We utilised longitudinal data from the Stockholm Public Health Cohort 2002, 2007, 2010, and 2014 including 3,373 individuals in the younger group, and 16,614 individuals aged 30-84 years (Study II). Third, we explored whether subjective well-being (SWB), i.e. emotional well-being and life satisfaction, is associated with personality traits at baseline and at 15-18 months of follow-up and whether personality traits may prospectively predict subjective well-being and vice versa. We employed our earlier data-collection from four secondary schools, two intervention- and two control schools, including 446 pupils (Study III). Finally, we investigated sustainable promotive and preventive mental health intervention effects for students in higher education. A systematic review and meta-analyses based on 26 included studies and a study population of 8,136 individuals were conducted (Study IV). Results: Study I. The General Health Questionnaire 12 (GHQ-12) in the National Health Survey revealed a capacity to measure PMH as well as NMH. However, when we examined the association between the GHQ-12 scores and 22 potential determinants of health, we found that most determinants showed significant and opposing effects on both PMH and NMH. Nonetheless, female sex, economic strain, risky gambling, and, above all, suicide ideation and perceived humiliation increased NMH more than they decreased PMH, and could qualify as risk factors. Participating in societal events and moderate gambling elevated PMH more than they reduced NMH and could subsequently be ascribed as promotive factors. Being a student was associated with lower PMH and higher NMH compared to being employed. Lastly, PMH decreased as age increased in the group of 16-29 years, whereas no age-related changes were found for NMH. Study II. In the Stockholm Public Health Cohort, 46% for males and 36% for females reported stable mental health among young people aged 18-29 years, compared to 66% and 55% respectively, in the age group 30 years and above. Out of 17 possible determinants of health, six predicted stable mental health in the younger group: occupational status, especially employment, emotional support, being male, being born in Sweden, absence of financial strain, and consumption of fruit and berries. In the older age group, the pattern was similar, with 11 significant determinants of health. However, more determinants were related to social capital and health behaviour compared to the younger group, and a significant group difference was evident for physical activity and absence of financial strain with higher importance in the older group. Study III. Among secondary school pupils aged 16 years, SWB at baseline and follow-up was associated with low levels of Neuroticism, and high levels of Conscientiousness, Extraversion and Agreeableness. In particular, the correlation between SWB and Neuroticism was strong. Compared to boys, trait stability was significantly higher in girls. However, one exception was Neuroticism, the only trait with stability in boys. SWB showed one prospective effect, namely on Agreeableness and only in girls. For personality traits, no prospective effects on SWB were found. Study IV. According to our systematic review and meta-analysis combined effects for interventions designed to prevent mental ill health in students in higher education showed that the symptom reduction sustained up to 7-12 months postintervention, although the effect size was small, ES of -0.28 (95% CI -0.49, -0.08). Specifically, for depression the sustainability was up to 13-18 months, for anxiety up to 7-12 months, and for stress up to 3-6 months. The sustainability for interventions designed to increase positive mental health was up to 3-6 months for all effects combined, and the effect size was small, ES of 0.32 (95% CI 0.05, 0.59). Specifically, active coping sustained 3-6 months with a medium effect size, ES of 0.75 (95% CI 0.19, 1.30). Conclusions: In our national sample, the GHQ-12 did not systematically discriminate potential determinants associated to positive and negative mental health, respectively, and therefore should be reserved for its purpose of origin, namely to measure symptoms of mental ill health in the population. Our results which show that young females seem to perceive less stable mental health and higher levels of Neuroticism compared to their male peers confirm the results from earlier studies. This is also true regarding young people’s less stable mental health and higher levels of mental ill health symptoms compared to older age groups. As occupational status, especially employment, and emotional support may serve as determinants predicting mental health stability among young people, promoting them should be a matter of urgency. Interventions in higher education showed sustainable effects, and it may be of importance to endorse those interventions. As other interventions enhancing positive mental health, and those with a whole-system approach in schools, higher education, and working-life are less well explored, further research should shed a light on these important topics