Twin Study Shows Physical Activity May Decrease Dementia Mortality Interview with:
Paula Iso-Markku, MD,
Department of Clinical Physiology and Nuclear Medicine, 
HUS Medical Imaging Center, 
Helsinki University Central Hospital and University of Helsinki
Helsinki , Finland

MedicalResearch: What is the background for this study? What are the main findings?

Dr. Iso-Markku : The social, financial and humane burden of the dementia is extensive as the worldwide prevalence of dementia is estimated around 35.6 million. Finding efficient prevention strategies for dementia is crucial. Within the past decade vascular risk factors have been recognized as very potential risk factors of dementia. As physical activity is known to affect vascular risk factors, it might also be a potential preventive tool against dementia. Few comprehensive epidemiological studies on physical activity in middle age and dementia occurrence later in life have been conducted.

The comprehensive Finnish Twin Study offers a unique approach to the subjects as the shared growing up environment and genes can be taken into account. The study population is extensive and a good representation of the Finnish population. In this study the association of physical activity in adulthood and dementia mortality was investigated in a 29-year follow-up.

The main finding in this study was that persistent vigorous (i.e. more strenuous than walking) physical activity was significantly associated with lower dementia mortality. The results in the paired analysis, comparing twins to co-twins, were similar but remained non-significant. The analyses of the volume of physical activity were, however, controversial.

MedicalResearch: What should clinicians and patients take away from your report?

Dr. Iso-Markku : Late onset Alzheimer’s disease and vascular dementia cause the majority of dementia cases. The risk profile in these diseases is similar to that of cardiovascular diseases; smoking, type 2 diabetes, hypertension and dyslipidemia have been associated to greater dementia incidence.  Our gives additional evidence on that also physical inactivity is a risk factor for dementia.

MedicalResearch: What recommendations do you have for future research as a result of this study?

Dr. Iso-Markku :  The evidence of the association of physical activity and dementia remains still scarce. More good quality research on physical activity precisely in midlife and dementia incidence later in life is needed.


Ann Med. 2015 Jan 22:1-7. [Epub ahead of print]

Physical activity and dementia: Long-term follow-up study of adult twins.

Iso-Markku P, Waller K, Kujala UM, Kaprio J.