BACKGROUND: Case reports suggest that isotretinoin use is associated with an increased risk of cardiovascular disorders; however, the clinical significance has not been determined. OBJECTIVE: To determine whether isotretinoin increases the risk of cardiovascular outcomes. METHODS: A case crossover study was performed among subjects who filled ≥1 isotretinoin prescription during 1984-2003. Cases were defined as those with a first-ever diagnosis or hospitalization for acute myocardial infarction (MI), stroke, phlebitis/thrombophlebitis, pulmonary embolism (PE) or thrombosis. Exposure to isotretinoin in a 5-month hazard period immediately prior to the index date (calendar date of the diagnosis or hospitalization for the study outcomes) was compared to a 5-month control period. Odds ratios (ORs) along with 95% confidence intervals (CIs) were estimated using conditional logistic regression. RESULTS: Of 30,496 isotretinoin users identified, 872 (3%) cases met the inclusion criteria; 381 (43.7%) had a stroke, 268 (30.7%) phlebitis/thrombophlebitis, 133 (15.3%) MI, 61 (7.0%) PE and 29 (3.3%) thrombosis. When stratified according to type of outcome, ORs were 0.75 (95% CI: 0.38-1.47), 1.31 (95% CI: 0.64-2.69) and 2.00 (95% CI: 0.50-8.00) for stroke, phlebitis/thrombophlebitis and MI, respectively. CONCLUSION: No statistically significant association was found between isotretinoin and cardiovascular, cerebrovascular and thromboembolic outcomes.
BACKGROUND: Case reports suggest that isotretinoin use is associated with an increased risk of cardiovascular disorders; however, the clinical significance has not been determined. OBJECTIVE: To determine whether isotretinoin increases the risk of cardiovascular outcomes. METHODS: A case crossover study was performed among subjects who filled ≥1 isotretinoin prescription during 1984-2003. Cases were defined as those with a first-ever diagnosis or hospitalization for acute myocardial infarction (MI), stroke, phlebitis/thrombophlebitis, pulmonary embolism (PE) or thrombosis. Exposure to isotretinoin in a 5-month hazard period immediately prior to the index date (calendar date of the diagnosis or hospitalization for the study outcomes) was compared to a 5-month control period. Odds ratios (ORs) along with 95% confidence intervals (CIs) were estimated using conditional logistic regression. RESULTS: Of 30,496 isotretinoin users identified, 872 (3%) cases met the inclusion criteria; 381 (43.7%) had a stroke, 268 (30.7%) phlebitis/thrombophlebitis, 133 (15.3%) MI, 61 (7.0%) PE and 29 (3.3%) thrombosis. When stratified according to type of outcome, ORs were 0.75 (95% CI: 0.38-1.47), 1.31 (95% CI: 0.64-2.69) and 2.00 (95% CI: 0.50-8.00) for stroke, phlebitis/thrombophlebitis and MI, respectively. CONCLUSION: No statistically significant association was found between isotretinoin and cardiovascular, cerebrovascular and thromboembolic outcomes.