Objectives

To assess the relation of obesity to opioid use in people with or at risk of knee osteoarthritis (OA), and the extent to which this association is mediated by number of painful joints or depressive symptoms.

Methods

We used data from the Multicenter Osteoarthritis Study, a longitudinal cohort of older adults with or at risk of knee OA. Opioid use was identified by prescription medications and self-report. Obesity was defined as BMI ≥ 30 kg/m². Multi-joint pain was assessed using a standardized body homunculus, and depressive symptoms using the Center for Epidemiological Studies Depression scale. We quantified the direct and indirect effect of obesity on opioid use through the number of painful joints or depressive symptoms using causal mediation analysis by natural-effects models.

Results

We studied 2,335 participants (mean age: 68; mean BMI 31 kg/m²; 60% women). Persons with obesity had ∼50% higher odds of opioid use than those without. Estimates of indirect (mediated) effect by the number of painful joints and depressive symptoms suggested an increased odds of opioid use by 34% (odds ratio [OR] = 1.34, 95% CI: 1.04, 1.70) and 35% (OR 1.35, 95% CI: 1.05, 1.71), respectively, in obese vs non-obese individuals. The total effect of obesity on opioid use was higher in women than in men.

Conclusions

Multi-joint pain and depressive symptoms partially explained greater opioid use among obese persons with knee OA, demonstrating that the negative impact of obesity on knee OA extends beyond its influence on knee pain and structural progression.

中文翻译：

---

抑郁症状和多关节疼痛部分介导膝骨关节炎患者肥胖与阿片类药物使用之间的关系

目标

评估患有膝骨关节炎 (OA) 或有风险的人群中肥胖与阿片类药物使用的关系，以及这种关联在多大程度上是由关节疼痛或抑郁症状的数量介导的。

方法

我们使用了多中心骨关节炎研究的数据，该研究是患有或有膝骨关节炎风险的老年人的纵向队列。阿片类药物的使用是通过处方药和自我报告来确定的。肥胖定义为BMI≥30 kg/m ²。使用标准化的身体小人评估多关节疼痛，并使用流行病学研究中心抑郁量表评估抑郁症状。我们通过自然效应模型进行因果中介分析，通过关节疼痛或抑郁症状的数量来量化肥胖对阿片类药物使用的直接和间接影响。

结果

我们研究了 2,335 名参与者（平均年龄：68 岁；平均 BMI 31 kg/m ²；60% 为女性）。肥胖者使用阿片类药物的几率比非肥胖者高约 50%。对疼痛关节和抑郁症状数量的间接（介导）影响的估计表明，阿片类药物使用的几率增加了 34%（比值比 [OR] = 1.34，95% CI：1.04、1.70）和 35%（OR 1.35，肥胖者与非肥胖者的 95% CI 分别为：1.05、1.71）。肥胖对阿片类药物使用的总体影响在女性中高于男性。

结论

多关节疼痛和抑郁症状部分解释了患有膝骨关节炎的肥胖者更多地使用阿片类药物，这表明肥胖对膝关节骨关节炎的负面影响超出了其对膝关节疼痛和结构进展的影响。