Prevalence of Parkinson Disease in Italy: a systematic review and meta-analysis

Introduction: Parkinson’s disease (PD) is a common disease of unknown etiology. Even though ac-curate information on the epidemiology of PD is critical for defining appropriate health policies, epidemio-logical data on Parkinson’s disease (PD) in Italy are often defined as scant or conflicting. Our study attempted to provide an overview on the prevalence of (PD) by means of a systematic review and metanalysis of existing data. Material and methods: We searched into two different databases (PubMed and EMBASE), focusing on studies reporting the prevalence of PD in Italy. Data were extracted using a standardized assessment form, and results of such analyses were systematically reported, summarized and compared. Results: A total of 16 studies were eventually included in the analyses, with a prevalence rate of 193.7/100,000. Available reports were heterogeneous both in design and in eventual figures, and also prevalence estimates were affected by substantial heterogeneity. Interestingly, prevalence rates ranged from 37.8/100,000 inhabitants in subjects aged 0 to 64 years, to 578.7 in age group 65 to 75 years, and 1235.7 in age group 75 years or older. PD was sig-nificantly associated with male sex, but only in older age groups (i.e. Odds Ratio, or 1.37 95%CI 1.22-1.53, and or 1.31, 95%CI 1.21-1.42 for age groups 65-74 years and 75 years or more, respectively). Discussion and conclusion: While the observed variations in prevalence rates may result from environmental or genetic factors, differences in methodologies for case ascertainment and diagnostic criteria may have significantly affected our estimates. As a consequence, the comparability of existing studies is limited.