Comorbid Alzheimer Disease and Diabetes Linked to Compounded Health Challenges

Older adults with Alzheimer disease (AD) and diabetes face compounding adverse effects on blood pressure, medication use, and mental health, according to results of a study published in the Journal of Alzheimer’s Disease.

Researchers analyzed data from adults aged 50 years and older in the Uniform Data Set collected at US Alzheimer’s Disease Research Centers between 2005 and 2024. The study population (N=52,537) included individuals with AD alone (33.3%), diabetes alone (4.1%), both AD and diabetes (1.73%), and neither condition (60.9%). Across these cohorts, the proportions of women were 53.6%, 57.0%, 48.7%, and 61.0% (P <.01), respectively. Mean ages were 76.9, 73.8, 77.7, and 73.8 years (P <.01), and the proportions of White participants were 84.4%, 60.5%, 68%, and 82.6% (P <.01). Mean BMI values were 26.3, 30.8, 28.6, and 27.2 kg/m² (P <.01), respectively.

Compared with individuals without AD or diabetes, participants with comorbid AD and diabetes had the largest increase in systolic blood pressure (5.33 mmHg), followed by those with diabetes alone (2.36 mmHg) and AD alone (1.86 mmHg; all P <.01). Comorbid AD and diabetes was also associated with the greatest increase in number of medications used (0.66), compared with diabetes alone (0.52) and AD alone (0.24; all P <.01). The highest BMI was observed in participants with diabetes alone (2.90 kg/m²), followed by comorbid AD and diabetes (1.27 kg/m²), while AD alone was associated with a slight decrease (-0.75 kg/m²; all P <.01). Only AD alone was associated with higher diastolic blood pressure relative to controls (0.64 mmHg; P <.01).

These findings highlight the value of co-located chronic disease clinics that integrate geriatric, endocrinological, and neurological expertise.

Comorbid AD and diabetes was associated with the highest increased risk for schizophrenia (odds ratio [OR], 3.20; P £.01). Participants with comorbid AD and diabetes or AD alone also had higher risks for depression (OR range, 1.32-1.61; both P <.01) and anxiety (OR range, 1.38-1.56; both P <.01), but lower risk for speech apraxia (OR range, 0.11-0.12; both P £.05) and sleep disorder (OR range, 0.49-0.51; both P <.01). Comorbid AD and diabetes or diabetes alone were associated with increased risk for hypertension (OR range, 3.22-3.64; both P <.01) relative to controls.

All outcomes were moderated at least in part by age, gender, race and ethnicity, marital status, living situation, education level, independence, tobacco use, and/or alcohol consumption.

This study was limited by its reliance on clinician-reported diabetes status and by the use of convenience sampling.

The study authors concluded, “These findings highlight the value of co-located chronic disease clinics that integrate geriatric, endocrinological, and neurological expertise.”