Secular- and longitudinal trends in mental health among older adults in Norway: The Tromsø Study 2001-2016

Self-reported symptoms of anxiety and depression may help identify at-risk groups and examine mental health trends on the population level. This study examined sex-specific secular- and longitudinal trends in mental health among Norwegian older adults.

Data from the Tromsø Study (2001, 2007-2008, 2015-2016) were analyzed. Secular trend analyses involved 12,884 individuals aged 60-84 years (19,631 observations). Longitudinal trends analyses included a subset of 8,766 individuals born between 1917-1947. Depression and anxiety symptoms were measured using the HSCL-10. Scores ≥ 1.85 were used to identify cases with mental distress, a predictor for clinically diagnosed mental disorders. Linear mixed regression and multiple imputation were used for analysis.

From 2001 to 2016, age-adjusted proportions of mental distress among participants aged 60-84 years declined (overall: 9.8 % to 6.6 %, women: 13.7 % to 8.9 %, men: 5.0 % to 4.0 %). Secular trends revealed lower average symptom scores in 2016 than in 2001, particularly in anxiety symptoms and among women. The youngest birth cohorts (1942-1947) experienced the largest longitudinal reductions in HSCL-10 scores; -0.08 (95% confidence interval [CI]: -0.11, -0.04) among women, and -0.04 (95% CI: -0.08, -0.01) among men. The largest increase in HSCL-10 score occurred during 2001-2008 among women born 1917-1921 and among men born between 1922-1931.

Mental distress prevalence among older adults declined from 2001 to 2016. Mental health trends appear to be driven by reduced anxiety scores. Women exhibited stronger trends, narrowing sex differences in mental health. Further research is needed to elucidate these trends.