Risk of Dyslipidemia Associated With Oral Janus Kinase Inhibitors: A Systematic Review and Meta‐Analysis of Randomized Placebo‐Controlled Trials

Janus kinase inhibitors (JAKi) have sparked a new era in the treatment of immune-mediated diseases. While some studies have reported an increased incidence of dyslipidemia in JAKi-treated patients, the full extent of this adverse event is not established. The study aimed to assess the association between treatment with oral JAKi and dyslipidemia in phases 2 and 3 placebo-controlled randomized clinical trials (RCTs). A systematic review and meta-analysis were conducted, encompassing phase 2 and 3 RCTs. The Embase, PubMed, and Web of Science databases were searched up to March 9, 2025. Only RCTs reporting lipid levels before and after treatment with JAKi were included. Data were extracted for changes in high-density lipoprotein (HDL), low-density lipoprotein (LDL), total cholesterol (TC), and triglycerides (TG) with values reported in mg/dL. A total of 13 studies were included in the analysis, comprising nine studies on rheumatoid arthritis, two on atopic dermatitis, one on Crohn's disease, and one on psoriasis. The studies encompassed a total of 3978 patients treated with JAKi and 1680 controls. Across all indications, the mean difference between JAKi and placebo for individual drug, was increased by 6.07 mg/dL (95% confidence interval [CI], 5.01-7.14) for HDL and 9.05 mg/dL (95% CI, 7.78-10.32) for LDL for baricitinib; HDL 5.4 mg/dL (95% CI, 3.2-7.7) and LDL 12.4 mg/dL (95% CI, 8.9-15.9) for upadacitinib; HDL 7.0 mg/dL (95% CI, 5.7-8.3) and LDL 15.7 mg/dL (95% CI, 12.9-18.6) for tofacitinib; and lastly HDL 3.0 mg/dL (95% CI, 0.2-5.8) and LDL 14.9 mg/dL (95% CI, 3.6-26.3) for decernotinib. This systematic review and meta-analysis highlight the risk of dyslipidemia during treatment with JAKi, which could pose cardiovascular risks. Thus, regular assessments of cardiovascular risk factors and routine lipid monitoring in patients undergoing JAKi therapy may be essential for managing dyslipidemia and evaluating long-term cardiovascular safety.