OBJECTIVE

The effect of a healthy lifestyle on diabetes-related dementia remains unknown. We examined whether an active lifestyle and rich social network may counteract the increased risk of dementia in people with diabetes.

RESEARCH DESIGN AND METHODS

Dementia-free older adults from the Swedish National Study on Aging and Care in Kungsholmen (n = 2,650) were followed up for 10 years. Diabetes was ascertained on the basis of medical history, medication use, medical records, or glycated hemoglobin (HbA_1c) ≥6.5% and prediabetes as HbA_1c between 5.7 and 6.5%. Dementia was diagnosed by specialists following standard criteria. An active lifestyle was defined as a moderate to high (vs. low) level of engagement in leisure activities or a rich social network (having moderate to rich [vs. poor] social connections and support). Hazard ratios (HRs) of dementia risk were derived from Cox regression models.

RESULTS

There were 246 incident dementia cases during follow-up. Those with diabetes (n = 243), but not those with prediabetes (n = 921), had greater risk of dementia (adjusted HR 2.0 [95% CI 1.4–2.9]) than diabetes-free participants. Participants with diabetes but low level of engagement in leisure activities (HR 4.2 [95% CI 2.2–8.2]) or a poor social network (HR 3.4 [95% CI 1.9–6.1]) had greater dementia risk than diabetes-free participants with moderate to high levels of leisure activity engagement or a moderate to rich social network. In participants with diabetes, an active lifestyle (high level of engagement in leisure activities or a rich social network) was associated with less of a raised risk (HR 1.9 [95% CI 1.1–3.4]).

CONCLUSIONS

An active and socially integrated lifestyle may significantly counteract the detrimental effect of diabetes on dementia risk.