Arthritis Research Centre of Canada, 5591 No. 3 Road, Richmond, BC, V6X 2C7, Canada.
Rheumatology (Oxford). 2013 Jan;52(1):68-75. doi: 10.1093/rheumatology/kes353. Epub 2012 Nov 28.
To determine the effect of glucocorticoids (GCs) on acute myocardial infarction (MI) risk in patients with RA.
Using administrative health data, we conducted a population-based cohort study of 8384 incident RA cases (1997-2006). Primary exposure was incident GC use. MI events were ascertained using hospitalization and vital statistics data. We used Cox proportional-hazards models and modelled GC use as four alternative time-dependent variables (current use, current dose, cumulative dose and cumulative duration), adjusting for demographics, comorbidities, cardiovascular drug use, propensity score and RA characteristics. Sensitivity analyses explored potential effects of unmeasured confounding.
Within 50 238 person-years in 8384 RA cases, we identified 298 incident MI events. Multivariable models showed that current GC use was associated with 68% increased risk of MI [Hazard ratio (HR) = 1.68, 95% CI 1.14, 2.47]. Similarly, separate multivariable models showed that current daily dose (HR = 1.14, 95% CI 1.05, 1.24 per each 5 mg/day increase), cumulative duration of use (HR = 1.14, 95% CI 1.00, 1.29 per year of GC use) and total cumulative dose (HR = 1.06, 95% CI 1.02, 1.10 per gram accumulated in the past) were also associated with increased risk of MI. Furthermore, in the same multivariable model, current dose and cumulative use were independently associated with an increased risk of MI (10% per additional year on GCs and 13% per 5 mg/day increase).
GCs are associated with an increased risk of MI in RA. Our results suggest a dual effect of GCs on MI risk, an immediate effect mediated through current dosage and a long-term effect of cumulative exposure.
确定糖皮质激素（GCs）对类风湿关节炎（RA）患者急性心肌梗死（MI）风险的影响。
我们使用行政健康数据，对 8384 例新发 RA 病例（1997-2006 年）进行了基于人群的队列研究。主要暴露因素是新发生的 GC 使用。MI 事件通过住院和生命统计数据确定。我们使用 Cox 比例风险模型，并将 GC 使用建模为四个替代的时变变量（当前使用、当前剂量、累积剂量和累积持续时间），调整了人口统计学因素、合并症、心血管药物使用、倾向评分和 RA 特征。敏感性分析探讨了未测量混杂因素的潜在影响。
在 8384 例 RA 病例的 50238 人年中，我们发现 298 例新发 MI 事件。多变量模型显示，当前 GC 使用与 MI 风险增加 68%相关[风险比（HR）=1.68，95%可信区间（CI）1.14-2.47]。同样，单独的多变量模型显示，当前每日剂量（HR=1.14，95%CI 1.05-1.24，每增加 5mg/天）、累积使用时间（HR=1.14，95%CI 1.00-1.29，每使用一年 GC 增加 1.14 年）和总累积剂量（HR=1.06，95%CI 1.02-1.10，过去每累积 1 克增加 1.06）也与 MI 风险增加相关。此外，在相同的多变量模型中，当前剂量和累积使用与 MI 风险增加独立相关（GC 增加 1 年风险增加 10%，每日增加 5mg 风险增加 13%）。
GCs 与 RA 患者 MI 风险增加相关。我们的结果表明，GCs 对 MI 风险有双重作用，一种是通过当前剂量介导的即时效应，另一种是累积暴露的长期效应。
