The incidence of Parkinson's disease in the North-East of England.

BACKGROUND Parkinson's disease is a common disorder among older people. Accurate epidemiological information is essential to identify possible aetiological factors, plan health services and set priorities for medical research. OBJECTIVE to determine the incidence of idiopathic Parkinson's disease in a defined geographical area in the North-East of England. METHODS using a prospective, longitudinal design, we sought to identify every new case of Parkinson's disease arising in the Newcastle and Gateshead area in the North-East of England. The base population comprised 488 576 individuals and multiple sources of case ascertainment were employed. All the patients with newly diagnosed idiopathic Parkinson's disease or parkinsonism between 1 June 2009 and 31 May 2011 were invited to participate. Patients were examined by a specialist and followed longitudinally to permit diagnostic review. RESULTS we identified 257 potential cases, of whom 181 had suspected idiopathic Parkinson's disease. After a follow-up period of 18 months, 155 patients retained a clinical diagnosis of probable Parkinson's disease. The mean age at diagnosis was 72.4 ± 10 years. The crude incidence of PD in Newcastle and Gateshead was 15.9 per 100 000 persons per year (95% CI: 13.4-18.4). Age-standardised to the European population the incidence of Parkinson's disease was 12.0 per 100 000 (95% CI: 10.1-14.0). We found a higher crude incidence among men 17.7 per 100 000 (95% CI: 14.0-21.4) than women 14.0 per 100 000 (95% CI: 10.7-17.4). CONCLUSION in this prospective longitudinal study, the incidence rate of Parkinson's disease in North-East England is similar to that of other modern European and American studies.