Secular trends in prevalent mild cognitive impairment: Data from the Swedish population-based study Good Aging in Skåne

Abstract

Background: Research suggests that incident dementia is decreasing, yet research on secular trends of prodromal dementia such as mild cognitive impairment (MCI) is lacking. Methods: To determine change of MCI prevalence over time and potential explanatory factors, four baseline samples (years 2001–2020) of Swedish participants (n = 3910) aged 60 and 81 at examination were compared. Results: An overall drop of 9 to 10 percentage points in MCI prevalence between 2001 and 2020 was observed, with lower odds ratios (OR) for MCI in the latest birth cohorts compared to earliest (e.g., ORs for 60-year-olds in latest born = 0.53; 95% confidence interval [CI] 0.37–0.76). Adjustments for sociodemographic (e.g., education), lifestyle, vascular and metabolic health and depression could not fully explain the observed MCI decline (e.g., 60-year-olds, OR = 0.59; 95% CI 0.40–0.88). Discussion: Studies like this are imperative as even a slight postponement in the onset of dementia could have a substantial impact on future public health burden.