Reduced risk of Parkinson's disease associated with lower body mass index and heavy leisure-time physical activity

This is similar to what has been found previously in epidemiological studies looking at BMI and other measures of obesity preceding PD. It is the tendency that after diagnosis people tend to lose weight. Regarding physical activity, it is always difficult to know whether the subjects that had reduced physical activity pre-morbidly where not simply in an early phase of the disease.

Eur J Epidemiol. 2014 Mar 16. [Epub ahead of print]

Sääksjärvi K, Knekt P, Männistö S, Lyytinen J, Jääskeläinen T, Kanerva N, Heliövaara M.

Abstract

The risk factors for Parkinson's disease (PD) are not well established. We therefore examined the prediction of various lifestyle factors on the incidence of PD in a cohort drawn from the Finnish Mobile Clinic Health Examination Survey, conducted in 1973-1976. The study population comprised 6,715 men and women aged 50-79 years and free of PD at the baseline. All of the subjects completed a baseline health examination (including height and weight measurements) and a questionnaire providing information on leisure-time physical activity, smoking, and alcohol consumption. During a 22-year follow-up, 101 incident cases of PD occurred. The statistical analyses were based on Cox's model including age, sex, education, community density, occupation, coffee consumption, body mass index (BMI), leisure-time physical activity, smoking and alcohol consumption as independent variables. At first, BMI was not associated with PD risk, but after exclusion of the first 15 years of follow-up, an elevated risk appeared at higher BMI levels (P for trend 0.02). Furthermore, subjects with heavy leisure-time physical activity had a lower PD risk than those with no activity [relative risk (RR) 0.27, 95 % confidence interval (CI) 0.08-0.90]. In variance with findings for other chronic diseases, current smokers had a lower PD risk than those who had never smoked (RR 0.23, 95 % CI 0.08-0.67), and individuals with moderate alcohol intake (at the level of <5 g/day) had an elevated PD risk compared to non-drinkers. The results support the hypothesis that lifestyle factors predict the occurrence of Parkinson's disease, but more research is needed.