Reduced Risk of Parkinson’s Disease in Users of Calcium Channel Blockers: A Meta-Analysis

Table 1

Characteristics of cohort studies included in meta-analysis.

Author, year (country)^a	Cohort name	Cohort size	Follow-up period (start–end year)	Assessment of CCB use	Number of CCB users	Assessment of PD	Number of PD cases	Quality rating (NOC)
Pasternak et al. [15] 2012 (Denmark)^a	NR	25,73,281	8 (1998–2006)	Prescription drug registry	2,02,836	National patient registry	5,711	9^b
Simon et al. [17] 2010 (USA)^a	Nurses Health study & Health Professionals Follow-Up Study	1,71,355	16 (1986–2002)	Self-reported through structured questionnaire	3,826	Self-reported and after confirmed by medical records and physician	421	7^c
Louis et al. [16] 2009 (Spain)^a	Neurological Disorder in Central Spain	3,942	4 (1994–1998)	Self-reported	NR	Presence of any two cardinal signs and physician confirmed PD	NR	8^c

Country of study conducted.
^bHigh quality.
^cMedium quality.
USA: United States of America, NR: not reported, CCB: calcium channel blockers, PD: Parkinson’s disease, and NOC: Newcastle-Ottawa Scale.