Tomor Harnod1, Cheng-Li Lin2, Fung-Chang Sung2, Chia-Hung Kao3. 1. Department of Neurosurgery, Buddhist Tzu Chi General Hospital, Hualien, Taiwan; College of Medicine, Tzu Chi University, Hualien, Taiwan. 2. Management Office for Health Data, China Medical University Hospital, Taichung, Taiwan; Department of Public Health, China Medical University, Taichung, Taiwan. 3. Department of Nuclear Medicine and PET Center, China Medical University Hospital, Taichung, Taiwan; Graduate Institute of Clinical Medical Science, School of Medicine, College of Medicine, China Medical University, Taiwan. Electronic address: d10040@mail.cmuh.org.tw.
Abstract
OBJECTIVE: This study was designed to evaluate the impact of long-term benzodiazepine use on the subsequent risk of benign brain tumor (BBT) or malignant brain tumor (MBT) development. METHOD: We used data from the National Health Insurance System of Taiwan. For the study cohort, we identified 62,186 patients who had been prescribed benzodiazepine for at least 2 months between January 1, 2000 and December, 31, 2009. For each of the benzodiazepine cases, we randomly selected one insured person from the non-benzodiazepine cohort with frequency matching sex, age, and year of index date. The non-benzodiazepine cohort comprised 62,050 patients. The related hazard ratios (HRs) and 95% confidence intervals (CIs) of developing brain tumors were investigated. RESULTS: The overall BBT incidence rate was 3.33-fold higher in the benzodiazepine cohort than the non-benzodiazepine cohort (46.3 vs 13.9 per 100,000 person-years) with an adjusted HR of 3.15 (95% CI=2.37-4.20). Similarly, the MBT incidence rate was 84% higher in the benzodiazepine cohort (3.71 vs 2.02 per 1000 person-years), and the adjusted HR of 1.21 (95% CI=0.52-2.81) was not statistically significant. When compared with the non-benzodiazepine cohort, the adjusted HRs of BBTs increased with benzodiazepine dosage (adjusted HR=2.12, 95% CI=1.45-3.10, for 36-150 mg/year; adjusted HR=7.03, 95% CI=5.19-9.51, for ≥151 mg/year). CONCLUSION: In this population-based study, we found a significant increase in the risk of benign brain tumor development in a cohort of long-term BZD users.
OBJECTIVE: This study was designed to evaluate the impact of long-term benzodiazepine use on the subsequent risk of benign brain tumor (BBT) or malignant brain tumor (MBT) development. METHOD: We used data from the National Health Insurance System of Taiwan. For the study cohort, we identified 62,186 patients who had been prescribed benzodiazepine for at least 2 months between January 1, 2000 and December, 31, 2009. For each of the benzodiazepine cases, we randomly selected one insured person from the non-benzodiazepine cohort with frequency matching sex, age, and year of index date. The non-benzodiazepine cohort comprised 62,050 patients. The related hazard ratios (HRs) and 95% confidence intervals (CIs) of developing brain tumors were investigated. RESULTS: The overall BBT incidence rate was 3.33-fold higher in the benzodiazepine cohort than the non-benzodiazepine cohort (46.3 vs 13.9 per 100,000 person-years) with an adjusted HR of 3.15 (95% CI=2.37-4.20). Similarly, the MBT incidence rate was 84% higher in the benzodiazepine cohort (3.71 vs 2.02 per 1000 person-years), and the adjusted HR of 1.21 (95% CI=0.52-2.81) was not statistically significant. When compared with the non-benzodiazepine cohort, the adjusted HRs of BBTs increased with benzodiazepine dosage (adjusted HR=2.12, 95% CI=1.45-3.10, for 36-150 mg/year; adjusted HR=7.03, 95% CI=5.19-9.51, for ≥151 mg/year). CONCLUSION: In this population-based study, we found a significant increase in the risk of benign brain tumor development in a cohort of long-term BZD users.