# Epidemiological trends and age-period-cohort effects on intracerebral hemorrhage burden across the BRICS-plus from 1992 to 2021

## TL;DR

This study examines how the burden of intracerebral hemorrhage has changed over time in BRICS-plus countries, finding a general decline but highlighting ongoing health inequalities.

## Contribution

The study provides new insights into age-period-cohort effects on ICH burden across diverse BRICS-plus nations.

## Key findings

- All BRICS-plus countries showed a decline in age-standardized ICH DALYs rates from 1992 to 2021.
- China had the highest ICH DALYs rate in 2021, while Brazil showed the most significant decrease.
- A strong negative correlation was found between ICH DALYs rates and the Socio-demographic Index.

## Abstract

Intracerebral hemorrhage (ICH) is a major global health concern associated with significant morbidity and mortality. The BRICS nations—comprising Brazil, Russian Federation, India, China, and South Africa—along with an expansion to include Saudi Arabia, Egypt, United Arab Emirates, Iran, and Ethiopia (BRICS-plus), represent a significant proportion of the global population and present unique health challenges. This study aims to evaluate the epidemiological trends and variations in the burden of ICH across BRICS-plus nations in a timely manner.

Data on the number, all-age rate, age-standardized rate, and relative change in ICH disability-adjusted life years (DALYs) from 1992 to 2021 within BRICS-plus were obtained from the Global Burden of Disease Study (GBD) 2021. Relationships between the DALYs rate and the Socio-demographic Index (SDI) were evaluated using Pearson correlation analyses. Additionally, age-period-cohort modeling was employed to estimate net drift, local drift, age, period, and cohort effects over the past three decades.

All BRICS-plus countries exhibited a declining trend in the age-standardized DALYs rate from 1992 to 2021. China reported the highest DALYs rate (1351.55 per 100,000 population) in 2021, while Brazil displayed the most significant decrease, at 64.53%. The annual net drift in the ICH DALYs rate ranged from −3.99% for Ethiopia to −1.61% for India among the ten countries. A significant negative correlation was observed between the DALYs rate of ICH and SDI values. Countries exhibited similar age effect patterns, with an increasing risk of DALYs rate with advancing age, as well as varying period and cohort effects, indicative of differential control measures and temporal burden trends.

The burden of ICH showed an overall declining trend across the BRICS-plus from 1992 to 2021, but persistent health inequalities between these countries were driven by socioeconomic disparities. Furthermore, it emphasizes the necessity for targeted interventions across age, period, and cohort dimensions to address the distinct challenges posed by ICH in these rapidly developing countries.