It has been estimated that there are 55 million people with dementia worldwide and the number is expected to triple in the next 30 years. Depression is thought to either be a risk factor or a biomarker for dementia, and as shown in the current study, depressive symptoms in the elderly nearly doubles the incidence of dementia.
Elderly patients (n = 6317) who were enrolled in the Health and Retirement Study and who had dementia and depressive symptom data were enrolled in the current study.
Depressive symptoms were assessed based on the Center for Epidemiologic Studies Depression (CES-D) Scale. A score > 4 was considered significant depressive symptoms.
At the end of the 8-year follow-up period, elderly patients who progressed from mild depressive symptoms or had persistently high depressive symptoms were shown to be at an increased risk for dementia (HR = 1.86 and 1.74, respectively).