Trends in Mortality of Renal Tubulointerstitial Diseases in the United States from 1999 to 2020 Using CDC WONDER Data

Purpose: Renal tubulointerstitial disease, also known as tubulointerstitial nephritis, involves primary injury to renal structures, leading to kidney inflammation. It may result from drug hypersensitivity, infections, or toxic exposures. This study examined mortality trends due to renal tubulointerstitial disease in the United States from 1999 to 2020 and evaluated disparities by demographic and geographic factors. Methods: Mortality data from 1999 to 2020 were obtained from the CDC WONDER database. Age-adjusted mortality rates (AAMRs) per 1,000,000 population and annual percent change (APC) with 95% confidence intervals were calculated. The Joinpoint Regression Program was used to assess temporal trends and demographic disparities. Results: A total of 7,341 deaths were recorded. AAMR increased from 15.228 in 1999 to 17.962 in 2020. APC trends showed an initial decline (1999–2011: −2.1150), followed by an increase (2011–2018: 3.8974) and a marked rise (2018–2020: 9.5021). Higher mortality occurred among Black individuals, males, those ≥ 85 years, rural residents, and individuals in the western US. Tests for parallelism revealed significant differences by sex (p = 0.000667), race (p = 0.00444), and region: Northeast vs. West (p = 0.009778), Northeast vs. South (p = 0.000222), Midwest vs. South (p = 0.014000), Midwest vs. West (p = 0.029111), and South vs. West (p = 0.000444). Significant differences were also observed between urban and rural populations (p = 0.028889). Conclusion: Mortality from renal tubulointerstitial disease has risen over the past two decades, with persistent demographic disparities. These findings underscore the need for targeted research and public health interventions to address these inequalities.