Influence of mental health and physical activity on memory complaints in older adults: results from the HUNT study

Subjective memory impairment, including short-term (STM) and long-term (LTM) memory complaints, is common in older adults and may signal underlying cognitive decline. Good mental health (MH) and physical activity (PA) have been associated with better cognitive functioning and reduced risk of memory problems, yet their relationships with self-reported memory complaints remain ambiguous. Additionally, the impact of mid-adulthood MH and PA on later-life memory complaints is not well understood. Few large-scale population-based studies have examined these associations longitudinally. This population-based study has two primary aims: (a) to examine the concurrent associations between self-reported MH, PA, and subjective memory complaints in older adults, and (b) to investigate the longitudinal associations between mid-adulthood MH and PA and memory complaints 11 years later, with both analyses controlling for demographic factors. This mixed cross-sectional and longitudinal study used data from the third (2006–2008) and the fourth (2017–2019) waves of the HUNT Study in Norway. Subjective self-reported STM and LTM complaints were measured by the nine-item Meta-Memory Questionnaire. The sample included 9,226 and 6,986 healthy participants from the HUNT3 and HUNT4 waves, respectively, who completed the questionnaire and were aged 60 or above by HUNT4. Independent t-tests, ANOVAs and linear regression analysis were used to examine group differences and associations between PA, MH, and memory complaints. While individuals with lower levels of PA had more STM complaints in both HUNT3 and HUNT4, these associations did not hold after adjustment for sociodemographic and mental health-related variables. However, male gender and MH problems – in particular depressive symptoms – were found to be related to LTM and STM complaints, concurrently and in part longitudinally. Male gender and MH - particularly depressive symptoms—emerged as consistently associated with both STM and LTM complaints in older adults, both concurrently and, to an extent, over time. Although PA initially appeared related to memory complaints, this association weakened after accounting for MH and sociodemographic factors. These findings highlight MH as a key modifiable factor in addressing memory complaints in aging. Future research should clarify the causal mechanisms linking depressive symptoms and subjective memory complaints.