Mortality in Parkinson's disease: a 20-year follow-up study

Abstract

We determined mortality rates and predictors of survival in 238 consecutive patients with Parkinson's disease (PD) with symptom onset between 1974 and 1984. All patients were regularly followed at the Movement Disorder Clinic (Department of Neurology at the Innsbruck Medical University) until December 31, 2004, or death. As of December 31, 2004, 189 patients had died. Standardized mortality ratios (SMRs) increased over time. SMRs were 0.6 (95% CI 0.4-1.0) by 5 years, 0.9 (95% CI 0.7-1.2) by 10 years, 1.2 (95% CI 1.0-1.4) by 15 years, and 1.3 (95% CI 1.1-1.5) by 20 to 30 years. SMR for male patients was significantly increased to 1.3 (95% CI 1.1-1.6), whereas SMR increase of 1.2 (0.9-1.4) observed in female patients was not significant. Significantly increased SMRs were detected in patients with younger and older age of onset. Male gender, gait disorder, lack of tremor, and lack of asymmetry as presenting clinical features predicted poor survival in a Cox's proportional hazard analysis. This study demonstrates similar survival of patients with PD to the normal control population up to a disease duration of 10 years, followed by a modest rise of mortality with disease duration beyond 10 years compared with the general population. Under regular specialist care using all currently available therapies life expectancy in PD does not appear seriously compromised, but male gender, gait disorder, and absent rest tremor at presentation are associated with poorer long-term survival.