Association between anemia and cognitive dysfunction in the hypertensive elderly: a cross-sectional study

Background Cognitive dysfunction has become one of the most serious social health problems around the world. Anemia may increase the risk of cognitive dysfunction in elderly population. Hypertension may also deteriorate cognitive function. Few studies reported the association of anemia and cognitive dysfunction in hypertensive elderly. Methods Data were obtained from the 2011–2014 National Health and Nutrition Examination Survey (NHANES). Cognitive performance was evaluated by the Consortium to Establish a Registry for Alzheimer’s Disease (CERAD) Word Learning subtest, the Animal Fluency Test (AFT), and the Digit Symbol Substitution Test (DSST). Multivariate logistic regression analysis and subgroup analysis were conducted to assess the relationship between anemia and cognitive dysfunction. Results A total of 2005 elderly participants (aged ≥ 60 years) were included. Anemia was associated with the greater risk of low cognitive performance in hypertensive elderly (OR = 1.427, 95% CI: 1.065–1.911). Anemia was associated with lower performance in AFT (OR = 1.331, 95% CI: 1.008–1.758) and DSST (OR = 1.818, 95% CI: 1.335–2.475). In subgroups of age younger than 65 or older than 80 years, being a female, being non-Hispanic White, with poverty income ratio less than 5.00, being a nonsmoker or nondrinker, anemia was significantly associated with cognitive dysfunction. Conclusions The findings of the present study suggest the existence of an association between anemia and low cognitive performance among hypertensive elderly. Clinical trial number: not applicable.