変形性股関節症は免疫チェックポイント阻害薬誘発性炎症性関節炎のリスク因子ではない

To evaluate whether hip osteoarthritis (OA) is a risk factor for checkpoint inhibitor-induced inflammatory arthritis (ICI-IA).

Patients treated for thoracic cancers with ICI therapy and with a CT of the abdomen/pelvis within one month of ICI start were included; hip OA was graded from a coronal slice of the CT by a radiologist. Chart review determined the presence of ICI-IA and other immune related adverse events Those with Kellgren-Lawrence grade of 2 or higher in either hip on CT abdomen/pelvis were classified as having hip OA. Incidence rates of ICI-IA were calculated in patients with and without hip OA. Development of ICIIA and overall survival were compared by Kaplan-Meier curves and Cox proportional hazards.

A total of 309 patients were included; 103 had hip OA on CT scan. Overall, the cumulative incidence of ICI-IA was 54.8/1000 person-years and did not significantly differ between those with and without hip OA (p=0.78). In the Cox proportional hazards model for ICI-IA development, hip OA was not associated with ICI-IA development (HR 1.24, p=0.55), but higher BMI was associated with a significantly lower hazard for ICI-IA (HR 0.93, p=0.049). Survival did not differ by hip OA status but was improved in patients with ICI-IA (HR 0.59, p=0.02) and higher BMI (HR 0.97, p=0.03) and worsened in higher cancer stage (HR 1.61, p=0.003) in the multivariable analysis.

CT-derived Hip OA was not significantly associated with development of ICI-IA in this cohort of lung cancer patients. ICI-IA was associated with decreased mortality.