Introduction: The period prevalence rate for anti-parkinson drugs (APD) use was reported in the Local Health Service of Ferrara (USL 31), Northern Italy, in 1988 (resident population: 177,000 inhabitants).
Material and methods: The study was performed through the analysis of the complete list of APD prescriptions in the USL 31 area provided by the computerized archives of USL 31 and the identification code of the patients which is unique for each resident of USL 31. The patients treated with neuroleptics known to be potential parkinsonism-inducing drugs were excluded.
Results: The period prevalence rate for APD users was 456.9 per 100,000 population. The prevalence rate for dopa derivatives users was 391.3 per 100,000. The prevalence did not varied between rural and urban zones of USL 31 both for APD and dopa derivatives users. A higher prevalence was obtained in a small rural commune of USL 31 both for APD users (758.5 per 100,000) and dopa derivatives users (718.6 per 100,000) than in the other 4 communes in which the study area is subdivided.
Conclusion: The reported prevalence could provide information on the occurrence of most parkinsonisms in the study area and some suggestion on the role of possible environmental factors.