Subjective memory complaints in later life: longitudinal evidence from the GERDA

Background

Subjective memory complaints (SMC) are common in later life and may indicate early cognitive decline. We examined longitudinal associations between social and health‑related factors and SMC, and factors related to changes in SMC over time.

Methods

Data from the GERDA study of adults aged ≥65 years in western Finland and northern Sweden (n = 4 872) collected in 2016 and 2021 was used. SMC were assessed with a single item (none, mild, severe). Baseline predictors included social contacts, associational membership, loneliness, self‑rated health, sleep quality, and depressive symptoms. Covariates were age, gender, education, civil status, and region. Ordinal logistic regression estimated adjusted odds ratios (OR) for higher SMC severity.

Results

In 2016, 55% reported no SMC, 39% mild, and 6% severe complaints. Over five years, 71% showed no change; deterioration was more common than improvement (19% vs. 11%). Half of those with severe SMC at baseline remained severe at follow‑up. Higher baseline SMC strongly predicted greater severity in 2021 (OR 7.87, p < 0.001). Compared with those aged 85, individuals aged 65 and 75 had lower odds of severe SMC. Women and those with good self‑rated health or no depressive symptoms had lower odds. Västerbotten (Sweden) showed higher odds of severe SMC than Pohjanmaa (Finland). Social participation, social contacts, loneliness, education, and civil status were not independently associated after adjustment.

Conclusions

SMC show moderate stability in later life and are primarily associated with prior complaints, older age, male gender, poorer self‑rated health, and depressive symptoms. Health factors appear to outweigh social factors in explaining SMC severity. Early identification of individuals with SMC and health problems is important, and regional differences warrant further investigation.

Key messages

• Subjective memory complaints in later life are moderately stable and predicted by prior complaints, older age, poor self‑rated health, and depressive symptoms.

• Health factors outweigh social factors in explaining subjective memory complaints, while regional differences merit further investigation.