Hospitalization after hydroxychloroquine initiation in patients with heart failure with preserved ejection fraction and autoimmune disease.

Background: Hydroxychloroquine (HCQ) reduces cardiovascular events among patients with autoimmune disorders and is being evaluated as a therapeutic option for populations with high-risk cardiovascular disease. However, recent studies have raised concerns about HCQ use and cardiovascular events.

Objective: To assess the association of HCQ initiation with heart failure-related and all-cause hospitalizations among patients with heart failure and preserved ejection fraction (HFpEF).

Methods: We conducted a cohort study of patients aged ≥18 years with diagnosed HFpEF and autoimmune disease using MarketScan Commercial and Medicare Supplemental databases (2007-2019). Patients were required to initiate HCQ after their first HFpEF diagnosis (HCQ users) or not (HCQ nonusers). For the patients in the HCQ users group, the first HCQ prescription date was assigned as the index date. Index date for the HCQ nonuser group was assigned by prescription-time distribution matching HCQ users, by utilizing the number of days from HFpEF diagnosis to the first HCQ prescription. After 1:≥3 propensity score (PS) matching, Cox proportional hazards regression models were used to compare HF-related and all-cause hospitalizations between users and nonusers.

Results: After PS matching, 2229 patients (592 HCQ users and 1637 HCQ nonusers) were included. After controlling for covariates, patients who received HCQ had lower risks of HF-related hospitalization (adjusted hazard ratio, 0.44; 95% CI, 0.24-0.82) and all-cause hospitalization (adjusted hazard ratio, 0.69; 95% CI, 0.57-0.83) compared with patients not using HCQ.

Conclusions: Among patients with HFpEF and autoimmune disease, initiation of HCQ use was associated with a decreased risk of HF-related and all-cause hospitalizations.