The Burden of Severe Periodontitis in China From 1990 to 2021, With Projections to 2050: A Comprehensive Analysis From The Global Burden of Disease Study 2021

Abstract

Background

The study aims to explore the epidemiologic information related to severe periodontitis in China.

Methods

We analyzed data from the Global Burden of Disease (GBD) 2021 study to delineate the incidence, prevalence, and disability-adjusted life years (DALYs) attributable to severe periodontitis in China, stratified by age and gender. A range of analytical methods, including comparative analysis, trend analysis, decomposition analysis, hierarchical cluster analysis, health inequality analysis, and predictive modeling, were employed to provide a comprehensive evaluation of the disease burden.

Results

The GBD 2021 estimated the annual age-standardized prevalence, incidence and DALYs of severe periodontitis in China to be 0.97% (95% CI: 0.83, 1.10), 10.80% (95% CI: 8.88, 12.78), and 70.15 per 100,000 (95% CI, 27.97, 144.15), respectively. The burden was higher in males than in females, with a marked increase observed in middle-aged and elderly populations. Trend analysis revealed a general rise in the burden of severe periodontitis in China over time. Decomposition analysis identified population growth and aging as the principal drivers of the increase in disease burden. Health inequality analysis indicated a growing disparity related to the Socio-Demographic Index (SDI), with a disproportionate burden concentrated in regions with higher SDI. Projections suggest that the burden of severe periodontitis in China will remain substantial from 2022 through 2050.

Conclusion

Future public health initiatives should prioritize enhancing the management of middle-aged and elderly populations, while simultaneously advancing public health systems in tandem with economic growth. These efforts are critical to effectively addressing the challenges posed by population growth and aging.

Clinical Relevance.

The burden of severe periodontitis in China is projected to remain substantial in the coming decades, driven largely by population growth and aging. Targeted preventive and control strategies will be essential to mitigate this burden, particularly among high-risk populations.

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Introduction

Periodontitis, a chronic inflammatory disorder, is marked by a cascade of bacterial-induced immune responses, resulting in progressive destruction of periodontal tissues.^1,2 And severe periodontitis is the primary cause of tooth loss in adults,³ leading to compromised masticatory function, malnutrition, and diminished quality of life. Recent data indicate that over 1 billion individuals globally were affected by periodontitis in 2021, with an age-standardized prevalence of 12.5%,⁴ underscoring the significant public health burden it represents. Furthermore, periodontitis has been implicated in the pathogenesis of several systemic conditions, including cardiovascular disease and diabetes,⁵ highlighting the imperative for effective management and prevention strategies.

As the world's most populous nation and largest developing country, China faces an equally serious epidemiologic burden of periodontitis. Data from the Fourth National Oral Health Survey (2015-2016) reveal a continued rise in the prevalence and severity of periodontal disease, with significant consequences for public health and quality of life.⁶ Moreover, China's population surpassed 1.4 billion according to the 2021 national census, with a growing proportion of elderly individuals.⁷ These demographic shifts are poised to further exacerbate the burden of periodontitis. In this context, a detailed analysis of the historical trends and current burden of severe periodontitis in China, as well as a comparison on a global scale, is of critical importance.

This study provides a comprehensive and systematic assessment of the temporal trends and dynamic evolution of the burden of severe periodontitis in China from 1990 to 2021, with projections extending to 2050, based on the GBD 2021. Using a range of analytical methods, the findings offer valuable insights for policymakers to evaluate the overall burden of severe periodontitis in China. Furthermore, a multilevel comparative analysis positions China within the global context of periodontitis burden, supporting efforts to enhance prevention strategies and optimize the allocation of health resources by drawing on successful experiences from other countries.

Methods

Data sources and disease definition

The GBD 2021 study, conducted by the Institute for Health Metrics and Evaluation (IHME) at the University of Washington, comprehensively evaluated the burden of 369 diseases and 88 risk factors across 204 countries and territories from 1990 to 2021.⁸ In the GBD 2021 analysis, severe periodontitis was defined with the following criteria: Community Periodontal Index (CPI) = 4, Clinical Attachment Loss (CAL) > 6 mm, and Probing Pocket Depth (PPD) > 5 mm. It should be noted that any 1 of these criteria being met was considered sufficient for diagnosing severe periodontitis.Disability-adjusted life years (DALYs), calculated as the sum of years lived with disability (YLDs) and years of life lost (YLLs) due to premature death, were used to assess both the fatal and nonfatal impacts of periodontitis.⁹ The Sociodemographic Index (SDI), a composite measure of socioeconomic status, incorporates total fertility, mean years of education, and lagged per capita income for individuals aged 15 years and older in each region.¹⁰ Given the use of publicly available data, this study did not require ethical approval or informed consent.

Descriptive analysis

To comprehensively assess the burden of severe periodontitis in China and globally from 1990 to 2021, we performed descriptive analyses stratified by age and sex, examining incidence, prevalence, and DALYs.

Trend analysis

To examine temporal trends in severe periodontitis, we quantified the overall burden of disease using the estimated annual percentage change (EAPC). Annual incidence rates were log-transformed, and a linear regression model was applied to calculate the slope between time and the logarithmic values. EAPC was computed using the formula $\text{EAPC}=\left(\text{eb}^-1\right)\times 100$ where b represents the regression slope. Positive EAPC values indicate an increasing trend, while negative values reflect a decreasing trend.¹¹

We further examined localized trends in severe periodontitis using joinpoint regression analysis, a method frequently employed in epidemiologic studies.^12,13 This approach combines multiple linear regression models, segments them into time intervals, and fits a regression line within each interval,¹⁴ providing more accurate trend analysis than traditional linear regression.¹⁵ Analyses were performed using Joinpoint software (version 4.9.1.0; National Cancer Institute, Rockville, MD, USA), calculating the annual percentage change (APC) and average annual percentage change (AAPC). An APC or AAPC greater than 0 indicates an upward trend, while values less than 0 indicate a downward trend.

We also investigated the effects of age, period, and birth cohort on trends in the burden of severe periodontitis using the age-period-cohort (APC) model. This model, based on a Poisson distribution, incorporates age, period, and cohort simultaneously, addressing the identification issues that arise when these factors are analyzed independently.^16,17 Specifically, the age effect reflects the risk at different ages, the period effect captures societal-level changes over time, and the cohort effect assesses the influence of individual birth cohorts on disease burden.¹⁸ In this study, we recoded year data into consecutive 5-year intervals (1992-2021), stratified age into 17 groups (15-19 years to 90-94 years, with a 95+ category), and conducted analyses using a web-based tool (https://analysistools.cancer.gov/apc/).¹⁹

Decomposition analysis

To understand the factors driving changes in severe periodontitis incidence, prevalence, and DALYs from 1990 to 2021, we performed a decomposition analysis. We first divided these metrics by sex (female, male, both), then used the Das Gupta method to assess the contributions of epidemiological shifts, population growth, and aging to the observed changes.²⁰

Hierarchy cluster analysis

This analysis aimed to assess the similarity in trends related to the burden of severe periodontitis between China and countries in the European Union, G20, and East Asia. Hierarchical cluster analysis, an unsupervised machine learning technique, constructs a hierarchical structure by sequentially merging data points, making it well-suited for identifying natural groupings and patterns within datasets.²¹ In our analysis, 48 countries and regions were categorized into 4 groups based on changes in the burden of disease: significant increase, minor increase, stable or minor decrease, and significant decrease.

Cross-country inequality analysis

Health inequality analysis evaluates disparities in the distribution of disease burden across countries and regions, serving as a foundation for the development and refinement of public health policies. This analysis quantifies both absolute and relative inequalities between countries using the slope index of inequality (SII) and the concentration index (CI).²² The SII quantifies the linear relationship between health indicators and socioeconomic status and is derived through linear regression, with the SDI as the independent variable and the health indicator as the dependent variable.²³ The positive or negative values indicate that countries with higher or lower socioeconomic status, respectively, bear a disproportionate burden of severe periodontitis.²⁴

Predictive analysis

To enhance the formulation of public health policies and optimize healthcare resource allocation, we stratified the population by gender (female and male) and projected the burden of severe periodontitis in China through 2050 using a Bayesian-periodic-cohort (BAPC) model. The BAPC model is well-suited for predictive analyses, as its integration of the Integrated Nested Laplace Approximation (INLA) with the BAPC facilitates the approximation of the marginal posterior distribution. This approach effectively mitigates the mixing and convergence issues commonly associated with traditional methods relying on Markov chain Monte Carlo (MCMC) sampling.²⁵

Results

Descriptive analysis

In 2021, China recorded 18295038 new cases of severe periodontitis (95% CI: 15747998, 20729598), with a total prevalence of 220238287 cases (95% CI: 183074953, 258996015). The age-standardized incidence rate (ASIR), prevalence rate (ASPR), and DALYs were 0.97% (95% CI: 0.83, 1.10), 10.80% (95% CI: 8.88, 12.78), and 70.15 per 100,000 (95% CI: 27.97, 144.15), respectively (Table 1). Table 1 also provides comparative data for the global average, Asia, the G20, the European Union, and Japan. China's ASIR, ASPR, and DALYs were slightly lower than the averages for the global population, Asia, the G20, and the European Union, but higher than those observed in Japan.

Table 1.

All-age cases and age-standardized prevalence, incidence and DALYs rates for severe periodontitis

Location	1990			2021			EAPC (95%CI)
	Prevalence (per 100)	Incidence (per 100)	DALYs (per 100000)	Prevalence (per 100)	Incidence (per 100)	DALYs (per 100000)	Prevalence	Incidence	DALYs
China	11.08 (8.38, 13.87)	1.00 (0.79, 1.18)	72.13 (28.83, 156.29)	10.80 (8.88, 12.78)	0.97 (0.83, 1.10)	70.15 (27.97, 144.15)	2.93% (2.56, 3.30)	2.27% (2.03, 2.52)	2.91% (2.54, 3.29)
Global	12.28 (9.49, 15.06)	1.07 (0.85, 1.24)	79.62 (31.46, 169.62)	12.50 (10.53, 14.50)	1.07 (0.94, 1.20)	80.89 (32.47, 165.37)	2.18% (2.09, 2.27)	1.91% (1.85, 1.96)	2.17% (2.08, 2.26)
Asia	12.41 (9.53, 15.31)	1.07 (0.85, 1.24)	80.44 (31.85, 172.12)	13.17 (11.19, 15.16)	1.11 (0.97, 1.24)	85.31 (34.67, 171.13)	2.72% (2.60, 2.83)	2.32% (2.25, 2.39)	2.71% (2.59, 2.82)
European Union	10.99 (8.75, 13.28)	0.97 (0.79, 1.12)	71.41 (28.46, 148.61)	10.17(7.96, 12.57)	0.91 (0.75, 1.08)	65.9 (25.89, 137.03)	0.43% (0.26, 0.59)	0.47% (0.40, 0.53)	0.40% (0.23, 0.57)
G20	11.71 (8.99, 14.53)	1.04 (0.83, 1.21)	75.88 (30.06, 162.85)	12.51 (10.54, 14.46)	1.09 (0.95, 1.22)	80.99 (32.72, 164.86)	2.24% (2.13, 2.35)	1.90% (1.83, 1.97)	2.23% (2.12, 2.34)
Japan	9.04 (6.605,11.43)	0.84 (0.64, 1.02)	58.91 (23.25, 128.69)	9.21 (6.99, 11.66)	0.87 (0.69, 1.05)	59.78 (23.5, 121.91)	0.81% (0.46, 1.16)	0.74% (0.54, 0.94)	0.76% (0.41, 1.12)

DALYs, disability-adjusted life-years; EAPC, Estimated Annual Percentage Change.

Burden of severe periodontitis in different age groups in China in 1990 and 2021

Figure 1 presents a comparison of the incidence and prevalence of severe periodontitis across different age groups in China in 1990 and 2021, along with the corresponding crude rates. The incidence data indicate that severe periodontitis predominantly affects individuals over 40 years of age, with a marked increase observed from the 15-19 age group to the 40-44 age group. Regarding prevalence, the peak was noted in the 35-39 age group in 1990 and shifted to the 50-54 age group in 2021. Additionally, there was a substantial increase in prevalence among individuals aged 40 years and older in 2021 compared to 1990. This trend was similarly reflected in the prevalence data, showing a significant rise in the number of affected individuals in 2021, particularly among middle-aged and older populations. Comparable trends were observed in global, Asian, EU, G20, and Japanese analyses (Supplementary Figure1-5).

Figure 1.

Burden of severe periodontitis in China. (A) Age-standardized incidence rate and number of cases of severe periodontitis; (B) Age-standardized prevalence rate and number of cases of severe periodontitis; (C) Comparison of incidence by age group in 1990 and 2021; (D) Comparison of prevalence by age group in 1990 and 2021.

Gender disparities in the burden of periodontitis in different age groups in China

Figure 2 illustrates the differences in the burden of severe periodontitis between men and women across various age groups in China in 2021. It is evident that males experience a higher disease burden than females. In the gender-specific analysis of ASIR, ASPR, and Age-standardized DALYs rate, we observed that males in most age groups bear a greater burden than females across all 3 indicators.

Figure 2.

Age-standardized prevalence, incidence, and DALYs rates of severe periodontitis in China, 2021. (A) Age-standardized prevalence rate; (B) Age-standardized incidence rate; (C) Age-standardized DALYs rate.

Overall trends in severe periodontitis burden

In China, the incidence, prevalence, and DALYs of severe periodontitis increased by an average of 2.27% (95% CI: 2.03, 2.52), 2.93% (95% CI: 2.56, 3.30), and 2.91% (95% CI: 2.54, 3.29) per year from 1990 to 2021, respectively. These rates of increase were significantly higher than those observed in global, Asian, EU, G20, and Japan (Table 1). Figure 3 depicts the overall trends in incidence, prevalence, and DALYs from 1990 to 2021.

Figure 3.

Trend comparison of ASIR, ASPR, ASMR, and DALYs of severe periodontitis from 1990 to 2021.

Local trends in severe periodontitis burden using joinpoint regression analysis

Figure 4 presents the ASIR, ASPR and DALYs of severe periodontitis exhibited notable fluctuations over time. Specifically, a clear decline was observed in ASIR, ASPR, and DALYs between 1990-2000 and 2005-2010, while an upward trend occurred between 2000-2005 and 2010-2014. From 2014 to 2021, the ASIR remained relatively stable, whereas both ASPR and DALYs demonstrated a downward trend. Global, G20 and Japan revealed similar patterns, while the burden of periodontitis in the European Union and Asia has shown a rising trend since 2014 (Supplementary Figures11-15, Table S1-S18).

Figure 4.

Joinpoint regression analysis of ASIR, ASPR, DALYs in China from 1990 to 2021. (A) ASIR for both in China; (B) ASPR for both in China; (C) Age-standardized DALYs rate for both in China.

Age-period-cohort analysis on severe periodontitis incidence

The results of the APC analysis on the incidence of severe periodontitis in China are presented in Figure 5. After adjusting for period and birth cohort effects, a significant age-related effect on the incidence of severe periodontitis was observed, with the relative risk (RR) increasing until stabilizing, peaking at ages 50-54 years (Figure 5, Table 2). When controlling for age and birth cohort effects, a significant period effect was identified. Between 1995 and 2000, the RR was below 1, indicating a reduced relative risk of severe periodontitis. In 2010, the RR declined again, indicating a further reduction in risk, followed by a significant increase between 2010 and 2015, reflecting an elevated burden of severe periodontitis during this period. Since 2015, the RR has remained close to 1, indicating a stabilization of risk (Figure 5, Table 2). Controlling for age and period effects, birth cohort effects revealed an elevated risk in earlier birth cohorts (Figure 5, Table 2). Supplementary Figures 16-20 present comparable findings for the global, Asia, EU, G20, and Japan. Of particular note, the global, Asian, and G20 APC analyses reveal a marked increase in severe periodontitis incidence among more recent birth cohorts (Table S19-S23).

Figure 5.

Parameter estimates of age, period, and cohort effects on severe periodontitis. (A) Age effect on incidence; (B) Period effects on incidence; (C) Cohort effects on incidence.

Table 2.

RRs of incidence due to age, period and cohort effects in China

Factor	Incidence
	RR (95% CI)	P
Age (years)
15-19	69.075 (58.501, 81.56)	<.001
20-24	204.635 (183.637, 228.034)	<.001
25-29	451.768 (415.754, 490.901)	<.001
30-34	811.077 (755.63, 870.592)	<.001
35-39	1310.101 (1230.119, 1395.283)	<.001
40-44	1770.111 (1670.259, 1875.933)	<.001
45-49	2014.104 (1911.384, 2122.345)	<.001
50-54	2115.826 (2010.455, 2226.72)	<.001
55-59	2072.58 (1967.514, 2183.257)	<.001
60-64	1995.128 (1889.036, 2107.179)	<.001
65-69	1955.939 (1843.907, 2074.778)	<.001
70-74	1921.23 (1795.86, 2055.351)	<.001
75-79	1913.029 (1754.527, 2085.849)	<.001
80-84	1898.398 (1699.744, 2120.269)	<.001
85-89	1849.962 (1569.675, 2180.298)	<.001
90-94	1790.528 (1323.627, 2422.125)	<.001
95+	1735.754 (856.051, 3519.465)	<.001
Period
1992-1996	0.92 (0.872, 0.971)	<.001
1997-2001	0.887 (0.847, 0.928)	<.001
2002-2006	1 (1, 1)	<.001
2007-2011	0.887 (0.85, 0.926)	<.001
2012-2016	0.989 (0.94, 1.042)	<.001
2017-2021	0.989 (0.928, 1.054)	<.001
Cohort
1897	0.975 (0.027, 34.931)	<.001
1902	0.995 (0.325, 3.04)	<.001
1907	1.013 (0.633, 1.622)	<.001
1912	1.028 (0.797, 1.326)	<.001
1917	1.03 (0.873, 1.214)	<.001
1922	1.028 (0.912, 1.158)	<.001
1927	1.028 (0.936, 1.128)	<.001
1932	1.026 (0.95, 1.108)	<.001
1937	1.021 (0.955, 1.093)	<.001
1942	1.014 (0.953, 1.078)	<.001
1947	1 (1, 1)	<.001
1952	0.981 (0.93, 1.035)	<.001
1957	0.967 (0.916, 1.022)	<.001
1962	0.967 (0.914, 1.023)	<.001
1967	1 (0.944, 1.06)	<.001
1972	1.063 (0.999, 1.132)	<.001
1977	1.149 (1.07, 1.234)	<.001
1982	1.265 (1.165, 1.372)	<.001
1987	1.403 (1.278, 1.54)	<.001
1992	1.519 (1.34, 1.722)	<.001
1997	1.642 (1.343, 2.007)	<.001
2002	1.751 (1.193, 2.569)	<.001

CI, confidence interval.

Decomposition analysis

The burden of severe periodontitis in China has risen dramatically over the past 32 years, primarily driven by aging and population growth (Figure 6). Specifically, aging and population growth contributed to 50.18% and 55.76% of the increase in incidence, respectively. Aging accounted for 59.25% of the increase in prevalence, while population growth contributed 44.5%. Similarly, aging and population growth were responsible for 59.17% and 45.00% of the rise in DALYs, respectively (Table S24-S26). Notably, decomposition analyses for the global, Asian, G20, and EU populations indicated that population growth was the predominant factor behind the increased burden of severe periodontitis. In contrast, the rise in the burden of severe periodontitis in Japan was mainly attributed to aging (Figure 6).

Figure 6.

Changes in Incidence, Prevalence and DALYs of severe periodontitis according to aging, population growth and epidemiological change from 1990 to 2021 by subgroups of sexes. The black dot denotes the overall value of the change resulting from all 3 components. For each component, positive values represent increases; negative values represent decreases. Abbreviations: DALYs, disability-adjusted life years.

Hierarchy cluster analysis

To identify regions with similar trends in disease burden and better contextualize China's position, we conducted a hierarchical cluster analysis based on the EAPC for incidence, prevalence, and DALYs. The results for DALYs are presented in Figure 7. China was categorized in the significantly increasing segment, with an EAPC of 2.27% (95% CI: 2.03, 2.52). Turkey exhibited the most pronounced increase [EAPC: 5.29% (95% CI: 4.63, 5.96)], followed by Saudi Arabia [EAPC: 4.92% (95% CI: 4.73, 5.11)]. In contrast, Spain had the greatest reduction in periodontitis burden [EAPC: -3.66% (95% CI: -5.14, -2.20)]. Most EU member states exhibited either a slight increase or remained stable, with some showing small decreases. These findings were consistent across the stratified analysis of both incidence and prevalence (Supplementary Figure 21-22, Table S27).

Figure 7.

Results of cluster analysis based on the EAPC values of DALYs from 1990 to 2021. Abbreviations: EAPC, estimated annual percentage change; DALYs, disability-adjusted-life-years.

Cross-country inequality analysis

The health inequalities analysis revealed the burden of severe periodontitis have increased markedly over time (Figure 8). The SII demonstrated that the difference in DALYs between countries with the highest and lowest income levels rose from 7.60 (95% CI: -3.42, 18.63) DALYs per 100,000 in 1990 to 48.62 (95% CI: 34.34, 62.91) DALYs per 100,000 in 2021. Similarly, the CI increased from 0.01 (95% CI: -0.02, 0.03) in 1990 to 0.05 (95% CI: 0.02, 0.07) in 2021, indicating a growing imbalance in the distribution of the burden across countries with varying SDI levels. Notably, the burden of severe periodontitis in China has escalated significantly alongside economic development, with the magnitude of increase surpassing that observed in most other countries. A similar trend was found in the health inequality analysis of severe periodontitis incidence and prevalence (Supplementary Figures 23-24).

Figure 8.

Chart of health inequality analysis results of DALYs in severe periodontitis. (A) Health inequality regression curves of DALYs in severe periodontitis globally; (B) Concentration curves of DALYs in severe periodontitis globally.

Predictive analysis of severe periodontitis burden through 2050

Figure 9 illustrates the projected trends in severe periodontitis incidence and prevalence through 2050. From 2022 to 2050, the incidence and prevalence of severe periodontitis among both men and women in China are expected to remain at relatively high levels.

Figure 9.

Projection of age-standardized incidence and prevalence of severe periodontitis in China, 2022-2050. (A) ASIR of males; (B) ASIR of females; (C) ASPR of males; (D) ASPR of females. ASIR: age-standardized incidence rate; ASPR: age-standardized prevalence rate.

Discussion

In this study, we presented the most up-to-date data on the incidence, prevalence, and DALYs of severe periodontitis in China from 1990 to 2021, and conducted a comprehensive assessment of the disease burden through comparative, trend, decomposition, hierarchical clustering, health inequality, and predictive analyses. Our findings indicate that the burden of severe periodontitis in China is generally increasing, with a disproportionate impact on middle-aged and older individuals, and a higher burden observed in men compared to women. Decomposition analysis identified aging and population growth as the primary drivers of the rising burden. Health inequality analysis demonstrated a significant rise in SDI-related inequalities over time. Furthermore, predictive analysis suggests that the burden of severe periodontitis in China will remain at elevated levels through 2050.

Age-specific analyses demonstrated significant age-dependent variations in the burden of severe periodontitis in China, particularly among middle-aged and elderly populations. Severe periodontitis was prevalent in individuals over 40 years of age. This trend may be attributable to population aging, as the natural deterioration of periodontal tissues with age²⁶ and a decline in immune function.²⁷ The sharp rise in incidence from the 15-19 to 40-44 age groups may be closely associated with lifestyle changes as individuals transition into adulthood, such as smoking,²⁸ and alcohol consumption,²⁹ which are contributing factors to periodontitis. Notably, the age of onset has shifted significantly from the 35-39 years age group in 1990 to the 50-54 years age group in 2021, reflecting the cumulative burden of the disease in older populations. This shift may be linked to aging and the growing prevalence of chronic diseases, as studies have demonstrated strong associations between periodontitis and conditions such as cardiovascular disease³⁰ and diabetes mellitus.³¹ Gender-specific analyses showed that the burden of severe periodontitis was significantly higher in men than in women. Evidence suggests that sex hormones may influence periodontal health, with higher testosterone levels in men potentially contributing to a stronger inflammatory response and an elevated risk of severe periodontitis.³² Additionally, lifestyle factors may play a role, as men tend to have higher rates of smoking³³ and alcohol consumption.³⁴

The burden of severe periodontitis in China has generally been increasing, with notable fluctuations when the overall trend is divided into distinct phases. Specifically, the burden of severe periodontitis rose rapidly from 2010 to 2015, followed by a period of stability after 2015. The sharp increase in severe periodontitis burden during the earlier phase may be attributed to several factors. Jinli Liu et al. reported that China has the largest number of diabetic patients over the age of 20 worldwide.³⁵ Additionally, the China Health and Nutrition Examination Survey indicated a significant rise in obesity rates among individuals over 18 years of age.³⁶ Tobacco consumption is another key factor, with approximately 316 million smokers in China, 27.7% of whom are over the age of 15.³⁷ It is noteworthy that the State Council of China introduced the "Healthy China 2030" strategy in 2016, aimed at strengthening the prevention and control of chronic diseases. This initiative may explain the stabilization of the severe periodontitis burden since 2015.

The APC model allows for the integration of age, period, and birth cohort effects.³⁸ Analysis of the age effect revealed that the incidence of severe periodontitis increases with age, peaking in the 50-54 years age group, a finding consistent with the study by Gustavo G. et al.⁴ This suggests that individuals within this age group should be prioritized for targeted prevention and management strategies. Regarding the period effect, the incidence of periodontitis stabilized after a rapid increase from 2010 to 2015, likely reflecting a combination of factors such as changes in lifestyle, the rising burden of chronic diseases, and the implementation of public health interventions. As for the birth cohort effect, our analysis indicated that individuals born earlier had a higher risk of developing severe periodontitis compared to those born later. This may be due to the earlier cohorts being exposed to more risk factors, while later cohorts benefited from improvements in oral care and preventive health measures.

Decomposition analysis indicates that the increasing burden of severe periodontitis in China is primarily attributable to population growth and aging. In contrast, the rising burden of severe periodontitis globally, as well as in Asia, the G20, and the European Union, is predominantly driven by population growth. Aging, a major risk factor for many oral diseases, including periodontitis, is of particular concern.³⁹ Projections suggest the global population will reach 9.7 billion by 2050, with 22% aged 60 years or older,⁴⁰ while China alone will have 400 million individuals over 65, of whom 150 million will be over 80.⁴¹ These demographic shifts underscore the urgent need for all countries to strengthen healthcare systems in anticipation of the public health challenges posed by population growth and aging.

Health inequality analysis revealed a significant increase in inequality over time, which was closely associated with economic development, consistent with previous studies.⁴² Notably, the rise in the burden of severe periodontitis with economic development was more pronounced in China compared to other countries. This disparity may be attributed to 2 factors: first, the imbalance between economic growth and healthcare investment in China, where health spending has not kept pace with rapid economic expansion⁴³; and second, the accelerated aging of the population, which has not been accompanied by a corresponding reduction in disease burden.

Projections indicate that the burden of severe periodontitis in China will remain high between 2022 and 2050. In light of this, it is imperative to strengthen early prevention and intervention efforts, particularly targeting high-risk populations, such as individuals aged 50 to 54. The rising burden of severe periodontitis can be mitigated through enhanced public health education, the promotion of regular dental checkups and healthy lifestyles, and the reduction of high-risk behaviors, such as smoking. Additionally, future research should focus on the association between severe periodontitis and other chronic diseases, fostering multidisciplinary collaboration to support more effective, comprehensive health management.

This study has several limitations. First, the analysis relies on the quality of the raw GBD data, which varies across countries and is subject to differing levels of data quality. Second, although the most recent GBD data were utilized, the inherent delay in interpreting trends in disease burden should be acknowledged. Third, the study was conducted at a national level, and the limited availability of data precluded a more detailed analysis of heterogeneity across provinces and ethnic groups within China.

Conclusion

This study demonstrates a substantial and sustained increase in the burden of severe periodontitis in China, with the greatest impact observed among middle-aged and elderly populations. The principal drivers of this rising burden are population growth and aging, underscoring the need for tailored preventive strategies.

Conflicts of Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.