MULTIFACTORIAL ETIOLOGY IN IDIOPATHIC PAR KINSONS-DISEASE - A CASE-CONTROL STUDY

The etiology of Parkinson's disease (PD) is currently thought to be du e to an interplay of genetic and environmental factors. We examined (1 ) familial prevalences of PD and essential tremor (ET) using a control population and personal investigation; (2) comorbidity and possible t raits of a altered premorbid lifestyle in PD were also investigated. S ixty-six PD patients with disease onset after 40 and before 70 years o f life and 72 age- and sex-matched hospital controls with chronic dise ases underwent neurologic examination and a structured interview. Alle gedly symptomatic relatives were investigated personally. - For the ti me prior to 40 years of age, PD patients reported significantly less f requent cigarette smoking overall (Odds ratio=OR 0.37); significantly less frequently a smoking duration of more than 2 years (OR 0.42); sig nificantly less frequently an amount of more than 10 cigarettes smoked per diem (OR 0.24); they did report, however, more frequently an onse t for smoking before the age of 20 (OR 3.56). Place of residence and s ource of drinking water during the first 15 years of life, and number of moves and journeys outside Europe before 40th year of life were not significantly different. PD patients demonstrated an increased risk o f a 1 st or 2nd degree relative with PD (OR 7.14) or ET (OR 3.62) comp ared to the control families. Congenital or perinatal abnormalities, a nd comorbid diseases did not suggest greater risk for PD. Stepwise log istic regression analysis yielded three variables that separated PD pa tients and controls most significantly, though not completely: ''smoki ng more than 10 cigarettes per diem'', ''additional family members wit h PD'', ''additional family members with ET''.