The Association between Clonal Hematopoiesis and Gout

Background: Gout is a highly prevalent arthritis associated with debilitating joint pain and functional impairment. It is caused by elevated serum uric acid levels (hyperuricemia) and triggered by precipitation of urate crystals in and around joints. Urate crystals are ingested by macrophages and provoke an innate immune response with subsequent secretion of inflammatory cytokines including interleukin 1 beta (IL-1B). Clonal hematopoiesis of indeterminate potential (CHIP) is a precursor to hematologic malignancies defined by somatic mutations in hematopoietic cells that drive clonal expansion and inflammation. Specifically, CHIP is associated with an increased risk of cardiovascular events and can accelerate atherosclerosis. Mutations in TET2, one of the most commonly mutated genes in CHIP, lead to increased expression of IL-1B through inflammasome activation. Here we investigate the role of CHIP in the development of gout using a combination of human genetic studies and mouse models of CHIP. Methods: To determine the clinical association between CHIP and gout, we analyzed exome sequencing and clinical data from >50,000 individuals included in the UK Biobank (UKB) and Mass General Brigham Biobank (MGBB). To test whether mutant blood cells can promote gout, Tet2- and Dnmt3a-deficient mouse models were used. Results: CHIP was more prevalent in individuals with gout than without gout (MGBB: 12.3% vs. 7.9%, P=0.017; UKB: 8.2% vs. 5.8%, P=0.011) and individuals with CHIP were at increased risk of developing gout (UKB: hazard ratio [HR], 1.59; 95% confidence interval [CI], 1.27-2.00; P Conclusion: CHIP is associated with an increased risk of having and developing gout in human cohorts and distinct mouse models confirm a direct influence of mutant hematopoietic cells on gout-induced inflammation and arthropathy. CHIP may provide a mechanistic explanation for the heterogeneity in clinical symptoms and inflammation due to gout. Our findings substantiate the biologic rationale for interventional strategies directed at CHIP-associated inflammatory conditions beyond cardiovascular disease and thereby define a path for clinical evaluation of targeted therapies for patients with CHIP-positive gout. Disclosures Miller: Foundation Medicine: Consultancy. Neuberg: Pharmacyclics: Research Funding; Madrigal Pharmaceuticals: Other: Stock ownership. Natarajan: Amgen: Research Funding; Apple: Consultancy, Research Funding; AstraZeneca: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Boston Scientific: Research Funding; Blackstone Life Sciences: Consultancy; Genentech: Consultancy; Foresite Labs: Consultancy. Rao: Janssen: Honoraria, Research Funding; Pfizer: Honoraria; Bristol-Myers Squibb: Honoraria, Research Funding; GlaxoSmithKline: Honoraria; Merck: Honoraria; Scipher Medicine: Honoraria.