The prevalence of Parkinson's disease in British Columbia, Canada, estimated by using drug tracer methodology.

OBJECTIVE: To estimate the prevalence of Parkinson's disease (PD) in British Columbia utilizing the prescription database of the College of Pharmacists. METHODS: Patients receiving anti-parkinsonian drug (anti-PD) prescriptions between 1996 and 1998 were stratified by year, age, gender, drug use category, and geographic location. The numbers of patients on levodopa alone, or levodopa and/or other anti-PD drugs were adjusted using published data which gave estimates of the proportion of undiagnosed patients with PD, the proportion of those treated for parkinsonism with definite PD, the proportion of patients with PD not being treated with anti-PD medications, and the proportion of patients treated with anti-PD medications who have PD. Use of the anti-PD drug bromocriptine for other purposes in women under 50 years of age was also considered. RESULTS: The estimated prevalences of PD based on all anti-PD medications used were 109, 121, and 125 per 100,000 population in 1996, 1997, and 1998, respectively. Estimated prevalences of PD based on levodopa use were 126, 134, and 144, respectively. The prevalence in both prescription groups increased with age. The male to female ratio of prevalence ranged from 1.16 to 1.21. CONCLUSIONS: Using a large, accurate database, it is possible to estimate the prevalence of PD in a large population, though the assumptions built into the estimate remain to be validated in the subject population.

Occupational and environmental risk factors for Parkinson's disease.

The etiology of Parkinson's disease (PD) remains obscure. Current research suggests that a variety of occupational and environmental risk factors may be linked to PD. This paper provides an overview of major occupational and environmental factors that have been associated with the development of PD and tries to assess current thinking about these factors and their possible mechanisms of operation. While clear links to rural living, dietary factors, exposure to metals, head injury, and exposure to infectious diseases during childhood have not been established, there is general agreement that smoking and exposure to pesticides affect the probability of developing PD.

Alternating two finger tapping with contralateral activation is an objective measure of clinical severity in Parkinson's disease and correlates with PET

We explored an objective method of measuring clinical severity of Parkinson's disease. Eighty-six patients with PD and 136 healthy subjects were studied. We serially carried out four types of finger tapping (FT) using a computerized drum machine: (i) repetitive one-finger tapping with an index-finger (F1K1); (ii) one-finger tapping on two keys separated by 20cm (F1K2); (iii) alternate tapping with index and middle fingers on two adjacent keys (F2K2); and (iv) F2K2 with contralateral activation (aF2K2). Analyses on FT included: (i) age and gender effects in healthy volunteers and Parkinson's disease; (ii) comparison between Parkinson patients and controls of similar age distribution; (iii) correlation with the Purdue Pegboard and Modified Columbia Scale in Disease; and (iv) in a subset of patients in whom PET scans were performed (n=30), correlation with 18F-DOPA uptake constant (Ki). In healthy subjects, there was a negative age effect on FT scores and a gender effect, with males scoring higher than females. All FT scores were significantly lower in the Parkinson patients, correlated with Purdue Peg Board, and inversely with the duration of illness, and with the Modified Columbia Scale. The 18F-DOPA Ki correlated significantly with aF2K2 (p=0.024), less so with PPB (p=0.038), but not with the Modified Columbia Scale. We conclude that alternating two-finger tapping with contralateral hand activation is a simple, objective test for measuring the severity of Parkinson's disease.