US Dementia-Related Mortality Rising with Greatest Impact Among Black Adults, Women, and in Nonurban Areas

Dementia-related mortality in the US has steadily and substantially increased over the past 2 decades, disproportionately affecting racial and ethnic minority groups and women, according to a new study that analyzed data from the CDC’s WONDER database for more than 6.5 million deaths between 1999 and 2020.

The annual age-adjusted dementia-related mortality rate (AAMR) per 10,000 individuals was highest among non-Hispanic Black adults (18.23) compared to non-Hispanic (NH) White (18.09), and Hispanic (12.7) adults between the ages of 35 years and older, including those aged 85 years and older. The increase in AAMR between 1999 and 2020 also was highest among individuals identifying as NH Black or African American, rising from 10.12 to 23.24, respectively, a jump of 13%. See below for increases for other groups represented in the study.

Previous studies have yielded similar trends in dementia-related mortality for Black adults, according to first author Mohsan Ali, MBBS, of the department of psychiatry at King Edward Medical University in Lahore, Pakistan, and colleagues. The factors underlying the increased risk are many and complex and include genetic variants, eg, ABCA7 and APOE 4, as well as longstanding inequities in health care and access to care, chronic health conditions, limited health literacy, and socioeconomic disadvantage, Ali and team wrote. They also emphasize that marginalized groups are less likely to receive early and accurate diagnoses, timely interventions, and support.

Their research was published online August 13, 2024, in the Primary Care Companion for CNS Disorders.

The overall dementia-related AAMR was 17.49, according to the study results, and higher among women (18.19) than among men (16.05). Ali and colleagues attribute the higher prevalence among women to the longer lifespan “as age stands out as the most significant risk factor for AD, the most prevalent form of dementia.” Both men and women experienced near two-fold increases in dementia-related mortality over the study period with the upward trend in AAMR for men from 10.16 in 1999 to 19.26 in 2020 and among women, from 11.08 in 1999 to 22.64 in 2020, according to the results.

Women do demonstrate a higher risk of developing dementia than men, the investigators added. They cite data from the Framingham Risk Study that found a woman aged 65 years has twice the lifetime risk of developing AD as a man of the same age. They call for research into both genetics and also environmental influences that may increase women’s vulnerability to Alzheimer disease and related dementias (ADRD).

Ali and colleagues attribute the higher prevalence among women to the longer lifespan “as age stands out as the most significant risk factor for AD, the most prevalent form of dementia.”

The results “also depict significant geographic variations in dementia-related mortality,” the team wrote, with nonmetropolitan areas seeing a greater increase in AAMR from 1999 to 2020 (11.69 to 24.06) compared with urban areas. The urban-rural divergence in ADRD … “is contributing significantly to the urban-rural life expectancy gap, particularly among women, surpassing the impact of other leading causes of death,” Ali et al wrote. They point to the rapidly aging rural areas of the country where socioeconomic resources are being depleted and health care infrastructure is in decline.

For the retrospective cohort analysis, Ali and fellow researchers tapped mortality data from the CDC’s Wide-Ranging Online Data for Epidemiologic Research (WONDER) database for individuals aged 35 to 85 years and older where the cause of death was listed as dementia/Alzheimer disease as a contributing or underlying cause of death. The designated time frame was 1999 to 2020. Mortality rates adjusted for age due to dementia were categorized by gender, racial and ethnic groups, and geography.

The research team reported a cumulative number of 6,601,680 dementia-associated deaths between 1999 and 2020 among individuals aged 35 years to age 85 years or older. Of the more than 6.5 million fatalities, 33.7% were men, thus 66.3% women. The distribution of race and ethnicity non-Hispanic White, 85.5%; NH Black, 8%; Hispanic or Latino 4.34%; NH Asian or pacific islander 1.6%; and AIAN, 0.3%. (Location – figure)

Future burden

“AD affects 6.2 million elderly Americans, ranking as the sixth leading cause of death in the United States and the fifth among those aged ≥65 years,” authors wrote in the study’s discussion. “With the aging population, AD cases are expected to rise significantly, with every US state projected to witness at least a 6.7% increase between 2020 and 2025.”

Ali and team observe that the impact on individuals will be mirrored in and extrapolated to the personal and social support systems meant to assist them and that would include families and government programs designed as resources for this population. “There is a critical need for targeted health care policy initiatives aimed at mitigating the increasing dementia burden,” they concluded

Source
Ali M, Talha M, Naseer B, Jaka S, Gunturu S. Divergent mortality patters associated with dementia in the United States: 1999-2020. Prim Care Companion CNS Disord. 2024;26(4):24m03724 . doi:10.4088/PCC.24m03724