Validation of Methods to Control for Immortal Time Bias in a Pharmacoepidemiologic Analysis of Renin–Angiotensin System Inhibitors in Type 2 Diabetes
スポンサーリンク
概要
- 論文の詳細を見る
Background: Pharmacoepidemiologic analysis can confirm whether drug efficacy in a randomized controlled trial (RCT) translates to effectiveness in real settings. We examined methods used to control for immortal time bias in an analysis of renin–angiotensin system (RAS) inhibitors as the reference cardioprotective drug.<BR>Methods: We analyzed data from 3928 patients with type 2 diabetes who were recruited into the Hong Kong Diabetes Registry between 1996 and 2005 and followed up to July 30, 2005. Different Cox models were used to obtain hazard ratios (HRs) for cardiovascular disease (CVD) associated with RAS inhibitors. These HRs were then compared to the HR of 0.92 reported in a recent meta-analysis of RCTs.<BR>Results: During a median follow-up period of 5.45 years, 7.23% (n = 284) patients developed CVD and 38.7% (n = 1519) were started on RAS inhibitors, with 39.1% of immortal time among the users. In multivariable analysis, time-dependent drug-exposure Cox models and Cox models that moved immortal time from users to nonusers both severely inflated the HR, and time-fixed models that included immortal time deflated the HR. Use of time-fixed Cox models that excluded immortal time resulted in a HR of only 0.89 (95% CI, 0.68–1.17) for CVD associated with RAS inhibitors, which is closer to the values reported in RCTs.<BR>Conclusions: In pharmacoepidemiologic analysis, time-dependent drug exposure models and models that move immortal time from users to nonusers may introduce substantial bias in investigations of the effects of RAS inhibitors on CVD in type 2 diabetes.
- 日本疫学会の論文
日本疫学会 | 論文
- Comparison of the National Nutritional Survey in Japan Estimated Individual-Based Nutritional Data and NIPPON DATA80 Food Frequency Questionnaires
- Fatty Acids Intakes and Serum Lipid Profiles: NIPPON DATA90 and the National Nutrition Monitoring
- Is Maternal Smoking during Early Pregnancy a Risk Factor for All Low Birth Weight Infants?
- High Serum Carotenoids Are Inversely Associated with Serum Gamma-glutamyltransferase in Alcohol Drinkers within Normal Liver Function
- Cardiovascular Risk Factors in Hemodialysis Patients : Results from Baseline Data of Kaleidoscopic Approaches to Patients with End-stage Renal Disease Study