Prevalence and incidence of chronic kidney diseases in Hong Kong: a 12-year territory-wide retrospective cohort study.

Background: Over the past decades, epidemiology studies on chronic kidney disease (CKD) have been widely conducted globally, but research on its prevalence and incidence in Chinese population remain scarce. This retrospective cohort study utilized all creatinine and urine albumin-to-creatinine ratio data obtained from the Clinical Data Analysis and Reporting System (CDARS), a territory-wide electronic medical database in Hong Kong, to provide the most up-to-date and largest Chinese cohort with long-term follow-up for comprehensive analysis of the trends in CKD prevalence and incidence. Methods: Patients diagnosed with CKD between 2010 and 2021 were identified from CDARS. Prevalence, crude incidence, and age-standardized incidence using the United Nations population in 2018 as a reference were estimated. Subgroups of age and sex were also estimated accordingly. Joinpoint regression was used to estimate the annual percent change (APC) and average annual percent change (AAPC). Findings: A total of 496,796 CKD patients between 2010 and 2021 were identified from CDARS. The prevalence of CKD (per 100,000 persons) increased from 3065.76 (95% confidence interval, CI: 3051.68-3079.88) to 6296.38 (95% CI: 6277.02-6315.78) between 2010 and 2021, with males generally having higher prevalence. The overall prevalence AAPC was 6.69% (95% CI: 6.45-7.03; p < 0.001), with the APC trend decelerating from 13.82% (95% CI: 11.17-16.10; p < 0.001) in 2012 to 4.06% (95% CI: 3.30-4.52; p < 0.001) in 2021. Both crude and age-standardized incidence (per 100,000 persons) showed a decreasing trend, in which the age-standardized incidence decreased from 533.61 (95% CI: 528.4-538.86) to 391.14 (95% CI: 387.2-395.11) between 2010 and 2021, with an AAPC of -3.74% (95% CI: -5.04 to -2.50; p < 0.001). Disparity in trends was observed among sex and age groups. Interpretation: The deceleration in CKD prevalence growth after 2012, along with the declining incidence trends may reflect the impact of the strategic framework launched by the Hong Kong government to prevent and control chronic diseases. Meanwhile, the sex differences in CKD trends support evidence that Asian males generally have a higher prevalence than females, differing from patterns observed in other regions. Further studies in diverse Asian populations are needed to reduce geographical bias and enhance understanding of CKD. Funding: None.