Pilot study of the incidence and prognosis of degenerative parkinsonian disorders in Aberdeen, United Kingdom: methods and preliminary results

The objective of this study was to test the methods for a large study of the incidence and prognosis of Parkinson's disease and other degenerative parkinsonian disorders and provide provisional incidence figures. This was a community-based prospective study to identify patients with newly diagnosed non-drug-induced Parkinsonism (>= 2 of tremor, rigidity, bradykinesia, postural instability) from a population of 148,600 people in Aberdeen, Scotland, over 18 months. Multiple search strategies were used to identify patients, including some population screening. Incident patients and age/sex-matched controls had assessments of impairment, disability, quality of life, mood, and cognition and are being followed up yearly. Two hundred and two people with possible parkinsonian symptoms were assessed, and 82 incident patients were identified, 50 with probable Parkinson's disease. The crude incidences of probable Parkinsonism and probable Parkinson's disease were 31.4/ 100,000/year (95% CI: 24.5-39.7) and 22.4/100,000/year (95% CI: 16.6-29.6), respectively. The mean age of diagnosis of Parkinson's disease was 76.1 +/- 10.0 years and the incidence was greater in men. The methods were generally successful. Provisionally, we found a higher incidence of Parkinson's disease than other comparable studies, and our patients were considerably older. This may reflect better case ascertainment in the elderly. A larger study is planned. (C) 2006 Movement Disorder Society.