BackgroundSymptoms of depression, anxiety, and distress are more common in undergraduates compared to age-matched peers. Mental ill health among students is associated with impaired academic achievement, worse occupational preparedness, and lower future occupational performance. Research on mental health promoting and mental ill health preventing interventions has shown promising short-term effects, though the sustainability of intervention benefits deserve closer attention. We aimed to identify, appraise and summarize existing data from randomized control trials (RCTs) reporting on whether the effects of mental health promoting and mental ill health preventing interventions were sustained at least three months post-intervention, and to analyze how the effects vary for different outcomes in relation to follow-up length. Further, we aimed to assess whether the effect sustainability varied by intervention type, study-level determinants and of participant characteristics.Material and MethodsA systematic search in MEDLINE, PsycInfo, ERIC, and Scopus was performed for RCTs published in 1995–2015 reporting an assessment of mental ill health and positive mental health outcomes for, at least, three months of post-intervention follow-up. Random-effect modeling was utilized for quantitative synthesis of the existing evidence with standardized mean difference (Hedges’ g) used to estimate an aggregated effect size. Sustainability of the effects of interventions was analyzed separately for 3–6 months, 7–12 months, and 13–18 months of post-intervention follow-up.ResultsAbout 26 studies were eligible after reviewing 6,571 citations. The pooled effects were mainly small, but significant for several categories of outcomes. Thus, for the combined mental ill health outcomes, symptom-reduction sustained up to 7–12 months post-intervention (standardized mean difference (Hedges’ g) effect size (ES) = −0.28 (95% CI [−0.49, −0.08])). Further, sustainability of symptom-reductions were evident for depression with intervention effect lasting up to 13–18 months (ES = −0.30 (95% CI [−0.51, −0.08])), for anxiety up to 7–12 months (ES = −0.27 (95% CI [−0.54, −0.01])), and for stress up to 3–6 months (ES = −0.30 (95% CI [−0.58, −0.03])). The effects of interventions to enhance positive mental health were sustained up to 3–6 months for the combined positive mental health outcomes (ES = 0.32 (95% CI [0.05, 0.59])). For enhanced active coping, sustainability up to 3–6 months was observed with a medium and significant effect (ES = 0.75 (95% CI [0.19, 1.30])).DiscussionThe evidence suggests long-term effect sustainability for mental ill health preventive interventions, especially for interventions to reduce the symptoms of depression and symptoms of anxiety. Interventions to promote positive mental health offer promising, but shorter-lasting effects. Future research should focus on mental health organizational interventions to examine their potential for students in tertiary education.

BackgroundThe dual continuum model suggests that positive mental health not only implies the absence of mental illness, but also constitutes an entity of its own. Measures that encompass both positive and negative mental health in young adults are rare. Thus, we assessed whether dimensions corresponding to positive and negative mental health could be identified in a sample of young individuals. Additionally, we explored how such dimensions were associated with potential health-related factors.MethodsWe obtained data from the Swedish National Public Health Survey 2004–2009 (23,394 women, 18,274 men, aged 16–29 years). We used exploratory factor analysis (EFA) to identify relevant factors revealed by the 12-item General Health Questionnaire (GHQ-12) and confirmatory factor analysis (CFA) to verify the factor structure. We tested the significance of the difference between effects of potential health-related factors on positive mental health (PMH) and negative mental health (NMH).ResultsThe EFA for the GHQ-12 revealed a two factor model with negative items that had high positive loadings on one factor and lower negative loadings on the other factor. The positive items had loading trends that were opposite those of the negative items. The fit of this model was supported by the CFA, which yielded a significantly better match than a unidimensional model. When we investigated the associations between GHQ-scores and potential predictors of health, we found that most potential predictors had significant and opposing effects on both PMH and NMH; with the strongest effects from suicidal ideation and perceived humiliation.ConclusionsOur results could be seen to indicate that positive and negative mental health are distinct and complementary constructs. Still, the results of our factor analysis may specifically reflect the wording of the items. We conclude that the GHQ-12 is an appropriate tool for its original purpose, to detect “psychiatric morbidity”. More refined measures, including predictors of health, are needed to assess PMH and validate the bidimensionality hypothesis.

Mental health has decreased in young people since the 1990s, and mental health promotion is an urgent matter. A first step is to identify which social determinants could be of importance for intervention. We used the Stockholm Public Health Cohort, a longitudinal population-based health survey, completed by 31,000 inhabitants in the Stockholm County. We focused on the 18–29 age group, n = 3373 (60% females, 40% males) and aimed at assessing which social determinants predict stable mental health, measured as scoring <3 points on the General Health Questionnaire 12 at all time points: 2002, 2007, 2010, and 2014. Forty-six percent of males and 36% of females reported stable mental health. Among the 17 predictors on sociodemographics, socioeconomics, social capital, health behavior, and victimization, six predicted stable mental health in the following order: occupation and especially employment, emotional support, male gender, being born in Sweden, absence of financial strain, and consumption of fruit and berries. In the 30–84 age group, 66% males and 55% females reported stable mental health. Nine determinants in the following rank predicted stable mental health: absence of financial strain, occupation and especially being self-employed, emotional support, male gender, physical activity, instrumental support, interpersonal trust, community trust, and absence of hazardous alcohol consumption. Interaction analysis showed significant difference between the younger and older group regarding physical activity and absence of financial strain with importance being higher for the older group. Our findings indicate that the determinants of health differ across the life-course with fewer predictors related to social capital and health behavior in the younger group compared to the older. We conclude that health-promoting interventions should be lifespan-sensitive.