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Published on: December 9, 2015
Prescription drug dispensations 15 years before multiple sclerosis onset: A matched cohort study, British Columbia,
Marta Ruiz-Algueró1, Seid Mussa Ahmed1, Feng Zhu1
1Faculty of Medicine (Neurology), UBC Hospital, University of British Columbia and The Djavad Mowafaghian Centre for Brain Health, Vancouver, BC, Canada.
Background:
Few studies assessed drug dispensations for periods >5 years pre-multiple sclerosis (MS) onset or examined the time pre-MS symptom onset.
Objective:
The objective of this study was to examine prescription drug dispensations up to 15 years pre-MS symptom onset.
Methods:
Matched cohort study linking prescription, clinical and administrative data, 1996-2018.
Results:
Among 1243/6212 MS/non-MS persons, those with MS had higher dispensation rate ratios (RRs) pre-onset for systemic antibacterials up to 15 years (RR (range) = 1.15-1.30; q-values (range) = 0.11-0.31), airway drugs up to 8 years (RR (range) = 1.49-1.71; q-values (range) = 0.26-0.35), sex hormones (females only) up to 7 years (RR (range) = 1.19-1.46; q-values (range) = 0.26-0.39) and psychoanaleptics up to 6 years (RR (range) = 1.36-1.59; q-values (range) = 0.09-0.31), but lower beta-blockers (years 13-14 pre-onset, RRs = 0.10; q-values (range) = <0.00001-0.31). After multiple-comparison adjustment, beta-blockers remained significant.
Conclusion:
Drug dispensations differed up to 15 years pre-MS onset and may reflect early disease.
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