Global, regional, and national burden of ischemic heart disease attributable to lead exposure, 1990-2021: decomposition, frontier, and projection analysis

Abstract

Introduction: Ischemic heart disease (IHD) is a leading global health burden, with lead exposure identified as a significant environment risk factor contributing to its prevalence.

Methods: Data from the Global Burden of Disease Study (GBD) 2021 were used to analyze deaths and disability-adjusted life years (DALYs) of IHD due to lead exposure at global, regional, and national levels. Decomposition analysis, frontier analysis, and Bayesian age-period cohort (BAPC) models were applied to assess trends from 1990 to 2021.

Results: In 2021, deaths and DALYs attributable to lead exposure reached 590,370.03 and 11,854,611.43, respectively, though age-standardized rates (ASRs) declined. Males and the older adult exhibited higher ASRs. At regional level, South Asia had the highest number of deaths and DALYs, while North Africa and the Middle East had the highest ASRs. Certain countries showed increasing ASRs over time, with a negative correlation between socio-demographic index (SDI) and ASRs. Decomposition analysis identified that population growth as the primary driver of increasing deaths and DALYs, particularly in middle-SDI regions. Frontier analysis suggested that middle and low-SDI regions have the greater potential to reduce the IHD burden. BAPC projections indicated a global decrease in IHD burden due to lead exposure by 2050.

Conclusions: The burden remains disproportionately high in males, the older adult and low- and middle-SDI regions, highlighting the need for targeted prevention and lead exposure control efforts in these populations.

Keywords: death; disability-adjusted life years; global burden; ischemic heart disease; lead exposure.

Figure 1

The global burden of IHD due to lead exposure in 1990 and 2021. (A, B) Sex-specific death and DALYs number for different age groups, 1990 and 2021. (C, D) Sex-specific mortality and DALYs rates for different age groups, 1990 and 2021. (E, F) Ranking of the burden of IHD due to different risk factors in 1990 and 2021. Error bars and shadow bands indicate 95% uncertainty interval. IHD: ischemic heart disease; DALYs: disability-adjusted life years. Risk factors are connected by lines between time periods, where solid lines represent an increase or no change in rank and dashed lines represent a decrease in rank.

Figure 2

Regional level burden of lead exposure IHD: sex-specific disparities and multiple disease comparative risk assessment (2021). (A) The ASMR of IHD due to lead exposure by sex at the regional level in 2021. (B) The ASMR of IHD due to lead exposure by sex at the regional level in 2021. (C) Ranking of the deaths number from 13 diseases caused by lead exposure. (D) Ranking of the DALYs number from 13 diseases caused by lead exposure. Error bars indicate 95% uncertainty intervals. IHD: ischemic heart disease; ASMR: age-standardized mortality rate; ASDR: age-standardized disability-adjusted life years rate.

Figure 3

Correlation between SDI and ASMR/ASDR of IHD due to lead exposure at the global and regional level from 1990 to 2021. (A) Correlation between SDI and ASMR, r = −0.3637, P < 0.001, df = 670. (B) Correlation between SDI and ASDR, r = −0.4389, P < 0.001, df = 670. Colored lines show global and regional values for ASRs, and each point in a line represents 1 year. Expected values based on the SDI and ASRs in all locations are shown as the line. SDI: socio-demographic index; IHD: ischemic heart disease; ASMR: age-standardized mortality rate; ASDR: age-standardized disability-adjusted life years rate.

Figure 4

The ASMR/ASDR of IHD due to lead exposure at the national level in 1990 and 2021. (A, B) The ASMR in 1990 and 2021. (C, D) The ASDR in 1990 and 2021. IHD: ischemic heart disease; ASMR: age-standardized mortality rate; ASDR: age-standardized disability-adjusted life years rate.

Figure 5

Correlation between SDI and ASMR/ASDR of IHD due to lead exposure at the national level in 2021 (A) Correlation between SDI and ASMR, r = −0.6443, P < 0.001, df = 6,526. (B) Correlation between SDI and ASDR, r = −0.6910, P < 0.001, df = 6,526. Each colored dot above represents a country, and the line represents the average expected value based on the SDI and ASRs in 204 countries and territories. SDI: socio-demographic index; ASRs, age-standardized rates; IHD: ischemic heart disease; ASMR: age-standardized mortality rate; ASDR: age-standardized disability-adjusted life years rate.

Figure 6

Correlation between the EAPC of ASMR/ASDR and SDI of IHD due to lead exposure at the national level in 2021. (A) Correlation between the EAPC of ASMR and SDI. (B) Correlation between the EAPC of ASDR and SDI. Each red dot above represents a country, and the line represents the average expected value based on the EAPC and SDI in 204 countries and territories. The size of the red dots represents the ASRs of the IHD. SDI: socio-demographic index; IHD: ischemic heart disease; EAPC: estimated annual percentage change; ASRs, age-standardized rates; ASMR: age-standardized mortality rate; ASDR: age-standardized disability-adjusted life years rate.

Figure 7

Changes in IHD due to exposure of deaths and DALYs numbers according to population growth, aging, and epidemiological change from 1990 to 2021 at the global level and by SDI quintile. (A) The driving factors of deaths number. (B) The driving factors of DALYs number. The black dot represents the overall value of change contributed by all three components. For each component, the magnitude of a positive value indicates a corresponding increase in IHD due to lead exposure of death and DALYs attributed to the component; the magnitude of a negative value indicates a corresponding decrease in IHD due to lead exposure of death and DALYs attributed to the related component. SDI: socio-demographic index; IHD: ischemic heart disease; DALYs: disability-adjusted life years.

Figure 8

Frontier analysis of SDI-based ASMR and ASDR for IHD in 2021. (A, B) The frontier values of ASMR and ASDR from 1990–2021 for all 204 countries with the SDI. (C, D) The frontier values in 2021 for all 204 countries. The red dots indicated that the rate in 2021 is higher than 1990, while the blue dots indicate that 2021 is lower than 1990. The dots marked in black are the 10 countries with the largest gap between the frontier and the actual value, the dots marked in red are the five countries with the largest gap between the frontier and the actual value for countries above the high SDI threshold, and the dots marked in blue are the five countries with the smallest gap between the frontier and the actual value for countries below the low SDI threshold. SDI: socio-demographic index; IHD: ischemic heart disease; ASMR: age-standardized mortality rate; ASDR: age-standardized disability-adjusted life years rate.

Figure 9

The projection of ASMR/ASDR of IHD due to lead exposure globally from 2021 to 2050. (A–C) The projection of ASMR and sex-specific ASMR. (D–F) The projection of ASDR and sex-specific ASDR. IHD: ischemic heart disease; ASRs: age-standardized rates; ASMR: age-standardized mortality rate; ASDR: age-standardized disability-adjusted life years rate.