# Inequalities in the burden of disease due to dementia, including Alzheimer disease, in British Columbia, Canada, from 2001 to 2022

## TL;DR

This study examines how dementia burden, measured by disability-adjusted life-years, has changed and varied by age, sex, and socioeconomic status in British Columbia from 2001 to 2022.

## Contribution

The study provides new insights into the widening socioeconomic gap in dementia burden and trends in incidence, prevalence, and mortality over two decades.

## Key findings

- Age-standardized dementia mortality increased by 1.6% annually since 2001.
- DALYs increased by 1.4% annually, with the most deprived socioeconomic group experiencing the fastest rise.
- The gap in dementia burden between socioeconomic groups has widened over time.

## Abstract

Disability-adjusted life-years (DALYs) integrate mortality and prevalence (or incidence) data. DALYs can be used as a surveillance measure to assess dementia burden and inequalities.

We utilized dementia case and mortality counts from linked administrative data to estimate incidence, prevalence, cause-specific mortality and DALYs in people aged 65 years and older, from 2001 to 2022, in British Columbia, Canada. Dementia-specific mortality rates adjusted for changes in death certification practices over time were estimated using logistic regression that incorporated multiple cause-of-death data from vital statistics records. All measures were stratified by sex; DALYs were also stratified by age and area-based socioeconomic status (SES) quintiles. Average annual percent change (AAPC) in rates was estimated using joinpoint regression.

Age-standardized dementia incidence and prevalence have declined since 2013, while mortality has increased by, on average, 1.6% per year since 2001 (95% CI: 1.4% to 1.8%). Age-standardized DALYs have increased by, on average, 1.4% per year (95% CI: 1.3% to 1.4%). DALY rates are highest in females aged 90 years and older but are increasing more rapidly in males. DALYs have declined for those in the least deprived SES quintile (AAPC: −0.6%; 95% CI: −1.0% to −0.3%) and conversely, have increased—with recent rates the highest—in the most deprived quintile (AAPC: 2.9%; 95% CI: 2.5% to 3.2%).

The socioeconomic gap in dementia disease burden has widened over time in British Columbia. DALYs are highest in females aged 90 years and older, but the overall gap between males and females has declined.