Parkinsonian signs in older people: prevalence and associations with smoking and coffee

Cigarette smoking and coffee consumption may reduce the risk of PD. Parkinsonian signs (tremor, rigidity, bradykinesia) occur in 30 to 40% of the elderly.

To determine whether there was an association between cigarette smoking, coffee consumption, and parkinsonian signs in a community population of older people.

Data on smoking were collected and a neurologic examination performed on 1,339 residents > or = 65 years of age in the Washington Heights-Inwood community in northern Manhattan, NY. Parkinsonian signs were rated with an abbreviated Unified Parkinson's Disease Rating Scale, resulting in a parkinsonian sign score. Coffee consumption was assessed with a semiquantitative food-frequency questionnaire, and caffeine consumption was determined. Analyses were cross-sectional.

Mean age was 76.6 years. Parkinsonian signs were present in 537 (40.1%). The odds for presence of parkinsonian signs was lower in smokers than nonsmokers (odds ratio [OR] = 0.58, 95% CI = 0.47 to 0.73). Smokers had a lower mean parkinsonian sign score than nonsmokers (p < 0.001). Coffee drinking and caffeine consumption were not associated with the presence of parkinsonian signs. The odds for presence of parkinsonian signs remained lower in smokers (OR = 0.75, 95% CI = 0.57 to 0.99) after adjusting for age, gender, ethnicity, years of education, adjusted daily caffeine consumption, and dementia.

The reduced risk of parkinsonian signs in cigarette smokers could reflect a protective effect of smoking on age-related parkinsonian signs in the elderly or an aversion to smoking in elderly persons with mild parkinsonism.