The Comparison Between Dietary Vitamin A Deficiency and the CRP Level in Alzheimer's Disease in Patients with Type 2 Diabetes: A Case-Control Study.

backgroundType 2 Diabetes Mellitus (T2DM) patients are 50-60% more likely to develop Alzheimer's Disease (AD). T2DM has many risk factors, including inflammation. Previous studies suggest that CRP was higher in diabetic patients, indicating that it may play a role in diabetogenesis and insulin resistance. Many diseases are prevalent in older age, including T2DM and AD. Moreover, multiple studies suggested a possible association between vitamin A levels, AD, and T2DM. However, the role of Vitamin A in Alzheimer's patients with T2DM has not yet been fully investigated. Therefore, this study aims to measure the association between dietary vitamin A deficiency and AD patients with T2DM in King Abdulaziz Medical City, Jeddah, Western Region, Saudi Arabia, to help expand the preexisting knowledge of the diagnostic risk factors of both the diseases and to determine the significance of vitamin A as a nutritional factor in their management and prevention.

methodsThis case-control study investigates the prevalence of vitamin A deficiency (VAD) among Alzheimer's disease (AD) patients with and without type 2 diabetes mellitus (T2DM). Participants included 103 AD patients aged 40 and older from the National Guard Hospital in Saudi Arabia, recruited between 2016 and 2022. Data collection occurred in two phases: first, through a review of medical records to gather demographic and health history information, including retrospective blood tests for systemic C-reactive protein (CRP) levels and comorbidities; second, using the HKI Food Frequency Questionnaire (FFQ) to assess dietary intake of vitamin A-rich foods over the past week, with caregiver interviews facilitating this process. Each subject was also prospectively interviewed to assess the presence of VAD events. The study aims to elucidate the relationship between dietary habits and VAD prevalence in AD patients, contributing to the understanding of nutritional impacts on cognitive health in this population.

resultsThis study examined demographic and clinical characteristics of the Alzheimer's group, with 70.1% having both Alzheimer's with T2DM and 29.9% having Alzheimer's alone. Significant differences in age were found (p-value = 0.03), but gender distribution was similar (p-value = 0.45). Most caregivers were sons, and 81.43% of patients received oral feeding. Comorbidities included hypertension (94.90%) and dyslipidemia (63.4%), with significant differences (p-value < 0.001). Correlation analyses showed weak negative correlations between CRP and vitamin A concentrations in both groups (Alzheimer with T2DM: p-value = 0.713, rho = -0.064; AD only: p-value = 0.223, rho = -0.121). Age and vitamin A levels also exhibited weak correlations: Alzheimer's with 2DM (p-value = 0.727, rho = 0.053) and Alzheimer's only (p-value = 0.223, rho = -0.253), neither of them was statistically significant. Symptoms of vitamin A deficiency were noted in Alzheimer's patients with T2DM, with no significant differences between groups. Dietary intake was lower for vitamin B complex, vitamin D, and multivitamins in AD patients with T2DM.

conclusionThe findings highlight the need for further investigation into the factors influencing vitamin A metabolism in these populations. Additionally, the prevalence of vitamin A deficiency symptoms and low dietary intake of essential nutrients among patients with Alzheimer's with T2DM suggests critical areas for nutritional intervention. Addressing these deficits may improve patient outcomes and enhance overall care strategies for individuals living with Alzheimer's disease.