Cross-sectional case-control studies (Blue)
The aim of the study was to assess the risk of hospitalisation for COVID‐19 and death in a cohort of patients with Parkinson’s disease or Parkinsonism compared to a control population cohort, during the epidemic bout (March‐May 2020) in Bologna, northern Italy. Participants of the ParkLink study with a clinical diagnosis of Parkinson’s disease or Parkinsonism, and people anonymously matched (ratio 1:10) for sex, age, district, and Charlson Index were included. The hospital admission rate for COVID‐19 (February 26 ‐ May 31, 2020) and the death rate for any cause were the outcomes of interest. The ParkLink cohort included 696 subjects with Parkinson’s disease and 184 with Parkinsonism; the control cohort contained 8,590 subjects. The 3‐month hospitalisation rate for COVID‐19 was 0.6% in Parkinson’s disease, 3.3% in Parkinsonism, and 0.7% in controls. The adjusted hazard ratio (age, sex, district, Charlson Index) was 0.8 (95% CI 0.3–2.3, p=0.74) in Parkinson’s disease and 3.3 (1.4‐7.6, p=0.006) in Parkinsonism compared to controls. Twenty‐nine of subjects who contracted the infection died; the 30‐day fatality rate was 35.1%, without any differences among the three groups. Six out of ten Parkinson’s disease/Parkinsonism patients had the infection during hospitalisation or in a nursing home. The authors concluded that PD per se is probably not a risk factor for COVID‐19 hospitalisation. Conversely, Parkinsonism is an independent risk factor probably due to more severe health problems, entailing higher care dependency and placement in high infection-risk accommodation.