Prevalence and Incidence of Rheumatoid Arthritis in Urban China: A National Population-Based Study.

INTRODUCTION

Rheumatoid arthritis (RA) is a global health problem with a heavy disease burden on both individuals and society. However, there is a lack of comprehensive nationwide data on RA prevalence, incidence, and associated economic burdens based on large-scale population studies in China.

METHODS

A population-based study was conducted based on data from the Urban Employee Basic Medical Insurance and Urban Resident Basic Medical Insurance claims covering 380 million residents from 23 provinces in China, from 2013 to 2017. The prevalence and incidence rates of RA stratified by sex, age, and region were estimated by a two-stage approach with Poisson regression models. The rates were age- and sex-standardized. The associated annual costs and hospital visit times were estimated.

RESULTS

789 583 patients were identified with a mean age of 54.74 ± 14.72 years, of whom 61.25% were female. The standardized prevalence rate of RA in China in 2017 was 334.35 (95% CI 288.20-383.92) per 100 000 people with 443.97 (95% CI 368.23-526.76) and 242.25 (95% CI 188.87-302.24) per 100 000 people in females and males. The prevalence increased at an average annual rate of 21.79%. The incidence rate in 2017 was 128.71 (95% CI, 101.69-158.91) per 100 000 person-years. The prevalence and incidence rates peaked at 65-74 years old in both sexes. The prevalence and incidence rates were lower in Southern China compared to other regions. The average annual cost per capita for RA patients was estimated to be US$907.78.

CONCLUSIONS

The high and rising prevalence, incidence, and medical costs of RA impose a substantial societal burden. Distinct patterns in prevalence across geographic regions require further research for underlying causes.