Mortality of Parkinson's disease in Italy from 1980 to 2015

To evaluate mortality for Parkinson's disease (PD) in Italy during a long time period (1980-2015) and to discuss the role of possible general and specific influencing factors.

Based on mortality data provided by the Italian National Institute of Statistics, sex- and age-specific crude mortality rates were computed, for the whole country and for its main geographical sub-areas. Rates were standardized using both direct (annual mortality rates AMRs) and indirect (standardized mortality rates SMRs) methods. SMRs were used to evaluate geographical differences, whereas AMRs and joinpoint linear regression analysis to study mortality trends.

Considering the entire period, highest mortality rates were observed in males (AMR/100,000: 9.0 in males, 5.25 in females), in North-West and Central Italy (SMR > 100). Overall PD mortality decreased from mid-eighties onwards and then rapidly reversed the trend in the period 1998-2002, rising up to a maximum in 2015, with some differences according to sex and geographical areas.

Several factors may have contributed to the rapid inversion of decreasing trend in mortality observed in the last part of XX century. Possible explanations of this rising trend are related to the increasing burden of PD (especially in males and in certain Italian regions), caused by different factors as population aging, physiological prevalence rise due to incidence exceeding mortality, and growing exposure to environmental or occupational risk factors. In addition, the accuracy of death certificate compilation could account for geographical differences and for the temporal trend. The role of levodopa and recently introduced dopaminergic drugs is also discussed.