Cognitive performance is associated with left ventricular function in older chronic hemodialysis patients: result of a pilot study

Background Cognitive impairment is a common finding in end-stage renal disease patients on chronic hemodialysis, but data on the associated factors are still scanty. Aims The present study evaluated the association between cognitive function and left ventricular systolic function in hemodialysis patients. Methods We enrolled 72 patients admitted to the Hemodialysis Unit of the Catholic University, Rome. Cognitive performance was evaluated using the Mini Mental State Examination (MMSE); a cutoff of 24 was used to diagnose cognitive impairment. Left ventricular ejection fraction (LVEF) was assessed by echocardiography. Multivariable linear and logistic regressions were adopted to assess the adjusted association between cognitive performance and LVEF. Also, linear discriminant analysis was performed to ascertain the cutoff level of LVEF which best predicted cognitive impairment. Results Cognitive impairment was found in 37 (51 %) patients. According to linear regression, MMSE was independently associated with LVEF (B = 0.06; 95 % CI = 0.01-0.12; P = 0.040). Logistic regression confirmed the inverse association between LVEF and cognitive impairment (OR = 0.87; 95 % CI = 0.78-0.98; P = 0.022). In linear discriminant analysis, the LVEF cutoff level that best predicted cognitive impairment was <= 51 %. Conclusion Cognitive impairment is a common finding in hemodialysis patients. Even mildly depressed LVEF is independently associated with cognitive impairment. This association and its potential therapeutic implications should be assessed in dedicated studies.