Aims While obesity is associated with an increased risk of complications after total hip arthroplasty (THA), the relationship between BMI and the risk of early postoperative complications has not been fully characterized. This study sought to describe the relationship between BMI and the risk of early postoperative complications, including periprosthetic joint infection (PJI), and composite surgical and composite medical complications. Methods Primary, elective THAs performed from 1 October 2015 to 31 December 2021 were identified using the Premier Healthcare Database. The study's primary outcome was the diagnosis of PJI within 90 days of THA. Using BMI as a continuous variable, logistic regression was used to develop restricted cubic splines (RCSs) to determine the impact of BMI on PJI risk. Bootstrap simulation was used to identify an inflection point in the final RCS model. The same technique was used to characterize the effects of BMI on composite medical and surgical complications. Results We found that PJI risk increased exponentially beyond a BMI threshold of 37.4 kg/m2. Relative to this threshold, patients with a BMI of 40 or 50 kg/m2 were at a 1.22-fold and 2.55-fold increased risk of developing PJI, respectively. Surgical complications increased at a BMI of 32 kg/m2 and medical complications increased at a BMI of 39 kg/m2. Relative to these cut points, patients with a BMI of 50 kg/m2 were at a 1.36-fold and 2.07-fold increased risk of developing medical and surgical complications, respectively. Conclusion The results of this study indicate a non-linear relationship between patient BMI and early postoperative risk of PJI, composite medical complications, and composite surgical complications following THA. The identified cut points with associated odds ratios can serve as tools to help risk-stratify and counsel patients seeking primary THA.

中文翻译：

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BMI 对全髋关节置换术后并发症风险的影响。


目的 虽然肥胖与全髋关节置换术 （THA） 后并发症风险增加有关，但 BMI 与术后早期并发症风险之间的关系尚未完全表征。本研究旨在描述 BMI 与术后早期并发症风险之间的关系，包括人工体周围关节感染 （PJI） 以及复合手术和复合医学并发症。方法 使用 Premier Healthcare Database 确定 2015 年 10 月 1 日至 2021 年 12 月 31 日期间进行的主要选择性 THA。该研究的主要结果是在 THA 后 90 天内诊断为 PJI。使用 BMI 作为连续变量，使用 logistic 回归开发限制性三次样条 （RCS） 以确定 BMI 对 PJI 风险的影响。Bootstrap 仿真用于识别最终 RCS 模型中的拐点。使用相同的技术来表征 BMI 对复合内科和手术并发症的影响。结果我们发现 PJI 风险在 BMI 阈值 37.4 kg/m2 之后呈指数级增加。相对于该阈值，BMI 为 40 或 50 kg/m2 的患者患 PJI 的风险分别增加了 1.22 倍和 2.55 倍。当 BMI 为 32 kg/m2 时，手术并发症增加，当 BMI 为 39 kg/m2 时，躯体并发症增加。相对于这些切点，BMI 为 50 kg/m2 的患者发生内科和手术并发症的风险分别增加了 1.36 倍和 2.07 倍。结论 本研究结果表明，患者 BMI 与 PJI 术后早期风险、复合躯体并发症和 THA 后复合手术并发症之间存在非线性关系。 确定的切入点和相关比值比可作为工具，帮助风险分层和咨询寻求原发性 THA 的患者。