Objectives: Although both heart disease (including heart failure, myocardial infarction, and coronary and peripheral artery diseases) and depression are associated with increased dementia risk, little research has been published evaluating the relationship between these conditions and dementia or Alzheimer’s disease (AD). The objective of this study was to explore the association between having both these comorbidities and developing dementia or AD.

Methods: This retrospective study analyzed electronic medical records database (Private Source 42) provided by HealthVerity Marketplace. Patients were required to have a diagnosis in an inpatient/outpatient setting between January 1, 2014 and June 30, 2019. Patients had at least 3 years of continuous enrollment. The participants characteristics were documented and the likelihood of developing dementia or AD was analyzed using adjusted models for logistic regression.

Results: There were 49,735 patients included in the analysis (age: 69.4±11.1 years; 52.7% male). At the study baseline, 13,294 (26.7%) had heart disease; 2,978 (6.7%) had depression; 1277 (2.6%) had both heart disease and depression. Analysis revealed that patients with heart disease or depression had a greater risk of developing dementia including Alzheimer’s disease and vascular dementia. Patients with both heart disease and depression were more likely to develop dementia (OR 3.47, 95% CI 2.76-4.36) and AD (OR 3.23, CI 1.93-5.41) compared to patients with only heart disease (OR 1.87, CI 1.65-2.12). These patients were also more likely to develop vascular dementia (OR 5.51, CI 3.04-10). Patients with depression were almost four times more likely to have dementia (OR 3.95, CI 3.37-4.62).

Conclusions: Our study showed that having both heart disease and depression was associated with higher odds of developing dementia and AD. Findings are important due to the high prevalence of dementia and AD. Therefore, early diagnosis and treatment of these comorbidities is vital to reduce the burden of dementia and AD.