Trends in Alzheimer's-Related Mortality Among Type 2 Diabetes Patients in the United States: 1999-2019

Recent research has shown that type 2 diabetes mellitus (T2DM) has increased the burden of Alzheimer's disease (AD) in the US aging population. However, trends in mortality from this comorbidity among adults aged ≥ 65 years have not been investigated.

This study examined trends and disparities in AD-related mortality among older US adults with T2DM from 1999 to 2019.

Data from the CDC WONDER database were analysed to assess AD-related mortality in patients with T2DM aged ≥ 65 between 1999 and 2019. Age-adjusted mortality rates (AAMRs) per 100,000 people and annual percent change (APC) were calculated and stratified by year, sex, race/ethnicity, age, urbanisation and geographical region.

From 1999 to 2019, there were 71,550 deaths with T2DM and AD among adults aged ≥ 65. AAMRs rose from 4.12 in 1999 to 11.65 in 2019, with the sharpest increase between 2014 and 2017 (APC: 10.81; 95% CI: -3.20 to 13.43). Women had slightly higher AAMRs than men, with rates increasing from 4.71 in 1999 to 11.61 in 2019 for women, and from 4.08 to 11.70 for men. Hispanic individuals saw the highest increase in AAMR (11.15), followed by non-Hispanic Black (9.30) and White populations (7.92). AAMRs were highest in the West (10.91) and the Midwest (9.62), while the Northeast (4.70) had the lowest. Nonmetropolitan areas had consistently higher AAMRs (10.74) than large metropolitan areas (6.68) and small/medium metropolitan areas (9.25). States in the top 90th percentile for T2DM-AD mortality included California, South Dakota and Kentucky, where rates were approximately eight times higher than in states in the lowest 10th percentile.

This study reveals a significant rise in T2DM-AD comorbidity-related mortality among older adults, especially among Hispanics, women and rural residents. These findings underscore the need for targeted interventions to reduce the burden in vulnerable populations.