Exploring Susceptibility of Dementia in Spouses of Diagnosed Patients: A Cross‐Sectional Study

ABSTRACT The number of patients with dementia is rising. Although there is abundant information on the prevalence of dementia, we specifically focused our sample in the Jimo region in China which has a higher than typical prevalence. Additionally, there is insufficient evidence concerning the effects of having a diagnosis of dementia on the spouse of the diagnosed patient. Evidence suggests that one spouse having cognitive impairment has a negative impact on the cognitive function of the other spouse. Studies suggest that when one spouse has dementia, the other spouse is also at risk for dementia. Hence, evidence suggests that when one spouse was experiencing dementia symptoms, the risk of dementia for the other spouse has been found to be higher than that whose spouse was not experiencing dementia symptoms and vice‐versa. The risk for dementia in the spouse of dementia patients needs to be further studied. To estimate the prevalence of dementia in the Jimo region in China and to provide evidence on the risk for dementia in the spouse of dementia patients from a local population. For the sample of over 6231 participants, a questionnaire survey was conducted on the general demographic information and the presence of chronic diseases. Fasting blood samples were collected for blood profile and blood biochemistry tests, and a 12‐lead electrocardiogram was performed on each subject. Mini‐Mental State Examination was used to assess the cognitive status of the subjects, and the Instrumental Activity of Daily Living scale was used for daily living abilities. Univariate analysis and multivariate logistic regression analysis were performed to identify the risk factors of dementia for the overall sample and within couples. This study followed the STROBE Protocol Statement's recommendations. The study results for the 1119 spouses suggest that the risk of dementia was significantly higher in both male and female spouses of diagnosed patients, with female spouses at a 5.591 times higher risk and male spouses at a 5.904 times higher risk compared to spouses without dementia, after adjusting for age, education, presence of coronary artery disease, stroke or diabetes, and high LDL‐C levels. For the full data set ( n = 6231), there was a 7.8% prevalence of dementia, where female gender, advanced age, coronary heart disease, stroke, diabetes, and high LDL‐C were identified as risk factors for dementia, while a higher level of education was a protective factor. For the Jimo region of China, the prevalence of dementia was slightly higher than in other regions, and our study generated evidence on the higher probabilities of dementia in spouses of patients already diagnosed with dementia. Although causality cannot be ascertained, the data in this study help support that there is an association among the spouses, but not necessarily a causal link. It is possible that both spouses have similar lifestyles, diet, and other shared environmental factors leading them both to dementia at some point.