Serum vitamin D and the risk of Parkinson disease.
OBJECTIVE
To investigate whether serum vitamin D level predicts the risk of Parkinson disease.


METHODS
Cohort study.


METHODS
The study was based on the Mini-Finland Health Survey, which was conducted from 1978 to 1980, with Parkinson disease occurrence follow-up through the end of 2007. During the 29-year follow-up period, 50 incident Parkinson disease cases occurred. Serum 25-hydroxyvitamin D level was determined from frozen samples stored at baseline. Estimates of the relationship between serum vitamin D concentration and Parkinson disease incidence were calculated using the Cox model.


METHODS
Three thousand one hundred seventy-three men and women, aged 50 to 79 years and free of Parkinson disease at baseline. Main Outcome Measure Parkinson disease incidence.


RESULTS
Individuals with higher serum vitamin D concentrations showed a reduced risk of Parkinson disease. The relative risk between the highest and lowest quartiles was 0.33 (95% confidence interval, 0.14-0.80) after adjustment for sex, age, marital status, education, alcohol consumption, leisure-time physical activity, smoking, body mass index, and month of blood draw.


CONCLUSIONS
The results are consistent with the suggestion that high vitamin D status provides protection against Parkinson disease. It cannot, however, be excluded that the finding is due to residual confounding and further studies are thus needed.
Knekt
Paul
P
National Institute for Health and Welfare, Helsinki, Finland. paul.knekt@thl.fi
Kilkkinen
Annamari
A
Rissanen
Harri
H
Marniemi
Jukka
J
Sääksjärvi
Katri
K
Heliövaara
Markku
M
D000368:Aged; D005260:Female; D005387:Finland / Q000453:epidemiology; D006306:Health Surveys; D006801:Humans; D015994:Incidence; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000097:blood* / Q000175:diagnosis; D016016:Proportional Hazards Models; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood
D014807:Vitamin D; C104450:25-hydroxyvitamin D