Physical activity in midlife seems to protect from dementia in old age, according to a study carried out at the University of Eastern Finland. Those who engaged in physical activity at least twice a week had a lower risk of dementia than those who were less active. The protective effects were particularly strong among overweight individuals. In addition, the results showed that becoming more physically active after midlife may also contribute to lowering dementia risk.
Several modifiable risk factors for dementia have been suggested, but further refinement of this information is essential for effective preventive interventions targeted at high-risk groups. Leisure-time physical activity (LTPA) is a particularly important due to its broader effects on health in general and cardiovascular health in particular. Previous research has yielded inconsistent evidence on the association between LTPA and dementia, possibly because of short follow-up time, intensity of physical activity or population characteristics such as sex, body mass index, age or genetic risk factors of dementia.
Recent findings from the Cardiovascular Risk Factors, Aging and Incidence of Dementia (CAIDE) Study demonstrated that those who engaged in leisure-time physical activity (LTPA) at least twice per week had lower risk of dementia in comparison to less active individuals. Although these protective effects were observed in the entire study population, regardless of their sex or genetic risk factors, they were particularly strong among overweight and obese individuals.
Becoming physically active after midlife may still lower the risk of dementia
Further staying physically active, or becoming more active, after midlife may also contribute to lowering dementia risk, especially in people who are overweight or obese at midlife. The findings were not explained by socioeconomic background, age, sex, genetic risk factors, obesity, weight loss, general health status or work-related physical activity.
These results suggest that the window of opportunity for physical activity interventions to prevent dementia may extend from midlife to older ages. Results from currently ongoing trials, such as the Finnish multi-center trial FINGER may give more detailed information about the type, intensity, and duration of physical activity interventions that can be used for preventing late-life cognitive decline.
CAIDE participants were derived from four separate, independent, population-based random samples examined in the North Karelia Project and FINMONICA study in 1972, 1977, 1982, or 1987. The average age at the beginning of the study was 50 years. This study included 1432 participants from Kuopio and Joensuu region, who attended cognitive tests in 1998 and 2005-2008. To account for survivor or selection bias, the analyses were also conducted among those 3242 North Karelia Project/FINMONICA-participants who were from Kuopio and Joensuu but did not attend the cognitive assessments using dementia diagnoses from registers.