Temporal trends and health inequalities in global, regional, and national years lived with disability of severe periodontitis from 1990 to 2021

This study evaluates changes in cross-national disparities in the burden of severe periodontitis between 1990 and 2021. All data on severe periodontitis used in this study were derived from the 2021 Global Burden of Disease (GBD) study. Annual years lived with disability (YLDs) and their estimated annual percentage changes (EAPCs) were calculated and stratified by year, age, geographical region, and socio-demographic index (SDI) at global, regional, and national levels. Decomposition analysis assessed the contributions of demographic and epidemiological factors to the evolving burden of severe periodontitis. A frontier analysis identified areas for improvement and disparities among countries based on development levels. Distributional inequalities were measured using the slope index of inequality (SII) and concentration index. The autoregressive integrated moving average model (ARIMA) was used to project the disease burden up to 2036. In 2021, there were 6,903.28 thousand YLDs (95% uncertainty interval [UI]: 2,772.28-14,106.18 thousand) attributed to severe periodontitis globally. Between 1990 and 2021, the global age-standardized rate (ASR) of YLDs showed a stable trend, increasing slightly from 79.62 (95% UI: 31.46-169.62) to 80.89 (95% UI: 32.47-165.37) with an EAPC of 0.08% (95% confidence interval [CI]: -0.03 to 0.18). Population growth accounted for 66.73% of the global increase in YLDs. SII values rose from 12.72 (95% CI: 1.92-23.52) in 1990 to 44.99 (95% CI: 31.14-58.85) in 2021, while the concentration index decreased from 0.05 (95% CI: -0.04 to 0.13) in 1990 to 0.035 (95% CI: -0.06 to 0.13). According to the forecasts, the global ASR of YLDs for severe periodontitis is projected to show a slight decline over the next 15 years. Significant potential exists for reducing the burden of severe periodontitis across countries, irrespective of their development levels. Severe periodontitis remains a significant global health challenge, with substantial cross-country disparities that persist despite overall stable trends in global YLDs. Targeted interventions and policies are urgently needed to address these disparities, focusing on improving oral health outcomes across all countries, regardless of their socio-demographic development levels.