Quantifying the contribution of rheumatoid arthritis to the acquisition of subsequent health care costs is an emerging focus of the rheumatologic community and payers of health care. Our objective was to determine the healthcare costs before and after diagnosis of rheumatoid arthritis (RA) from the public payer's perspective. The study design was a longitudinal observational administrative data-based cohort with RA cases from Ontario Canada (n = 104,933) and two control groups, matched 1:1 on year of cohort entry from 2001 to 2016. The first control group was matched on age, sex and calendar year of cohort entry (diagnosis year for those with RA); the second group added medical history to the match before RA diagnosis year. The main exposure was new onset RA. The secondary exposure was calendar year of RA diagnosis to compare attributable costs over the study observation window. Main outcomes were health care costs in 2015 Canadian dollars, overall and by cost category. We used attribution methods to classify costs into those associated with RA, those associated with comorbidities, and age/sex-related underlying costs. Health care costs associated with RA increased up to the year of diagnosis, where they reached $8,591: $4,142 in RA associated costs; $1,242 in RA comorbidity associated costs; and $3,207 in underlying costs. In the eighth-year post diagnosis, the RA costs declined to $2,567 while the RA comorbidity associated costs remained relatively constant at $1,142, and the underlying age/sex related cost increased to $4,426. RA patients had lower costs when diagnosed in later calendar years. Our results suggest a large proportion of disease related health care costs are a result of costs associated with RA comorbidities, which may appear many years before diagnosis.

中文翻译：

---

类风湿关节炎的医疗保健费用：一项纵向人群研究。

量化类风湿关节炎对以后获得医疗保健费用的贡献是风湿病界和医疗保健支付者的一个新兴焦点。我们的目标是从公共付款者的角度确定类风湿关节炎（RA）诊断前后的医疗费用。该研究设计是基于纵向观察性行政数据的队列研究，来自加拿大安大略省（n = 104,933）和两个对照组的RA病例，从2001年至2016年在队列输入年份匹配1：1。第一个对照组按年龄匹配队列的性别，性别和日历年（RA人群的诊断年）；第二组在RA诊断年之前将病史添加到比赛中。主要暴露是新发的RA。次要暴露是RA诊断的日历年，以比较研究观察期内的可归因成本。主要成果是总体医疗保健费用（按费用类别）的2015年加元医疗费用。我们使用归因方法将成本分类为与RA相关的成本，与合并症相关的成本以及与年龄/性别相关的基本成本。直到诊断之年，与RA相关的医疗保健费用都增加了，达到$ 8,591：RA相关的费用为$ 4,142。RA合并症相关费用为1,242美元；以及3,207美元的基本成本。在诊断后的第八年中，RA成本下降至$ 2,567，而与RA合并症相关的成本则保持相对恒定在$ 1,142，与年龄/性别相关的基本成本增加到$ 4,426。RA患者在以后的日历年中被诊断出费用较低。