This study investigates temporal trends and disparities in mortality among adults with both Alzheimer's disease (AD) and cerebrovascular disease in the US from 1999 to 2020.

AD and cerebrovascular disease often co-occur, sharing many risk factors such as hypertension, diabetes, and aging. Despite their frequent overlap, limited research has examined long-term mortality trends in individuals with both conditions.

We analyzed death certificate data (1999-2020) from the CDC WONDER database for adults aged ≥45 using ICD-10 codes for AD (G30) and cerebrovascular disease (I60-I69). Age-adjusted mortality rates (AAMRs) per 100,000 persons with 95% CIs were calculated by adjusting crude mortality rates (CMRs) to the 2000 US standard population. Annual percent changes (APCs) in AAMRs were assessed using Joinpoint regression, stratified by year, sex, race, and region. Statistical significance was set at P<0.05.

Between 1999 and 2020, 174,453 deaths were identified, primarily occurring in nursing homes and homes. Overall AAMRs declined (APC: -1.1, 95% CI: -1.4 to -0.9) over the 2 decades. After an initial rise from 8.3 (1999) to 9.1 (2002), AAMRs declined to 5.2 by 2013, before increasing to 6.8 by 2020 (APC 3). Females had higher mortality rates (AAMR 7.3 vs 5.9). Non-Hispanic Whites showed a decline from 8.4 to 6.8, while Hispanics’ AAMR rose from 5.1 to 6.3. No significant changes were observed in Asians or Non-Hispanic Blacks. Rural areas (8.5), the Western region (7.7), Vermont, and Washington (both 11.6) had the highest AAMRs, while the Northeastern region (3.9), Nevada (3), and New York (3) had the lowest.

While overall mortality decreased from 1999, AAMRs have risen since 2014, with females, Hispanics, and Non-Hispanic African Americans being most at risk. Regions with the highest AAMRs, particularly rural and Western areas, emphasize the need for targeted healthcare interventions to reduce disparities and improve outcomes.