The mind of a failing heart: a systematic review of the association between congestive heart failure and cognitive functioning

Background: Congestive heart failure (CHF) is a frequent complication of mo st diseases of the heart. CHF is associated with impairment in several aspe cts of the quality of life of patients, including mood and cognitive perfor mance. Early reports indicated that patients with CHF display deficits in m emory and other intellectual abilities, although the clinical relevance of these findings remains unclear. Aim: We reviewed systematically the medical literature with the aim of clar ifying the association between CHF and cognitive functioning. Methods: Systematic review of Medline database for studies published betwee n 1966 and June 2000 using the following key words: congestive heart failur e, cognition, cognitive disorders, memory, memory disorders, short-term mem ory, attention. Results: Thirteen studies reported cognitive information on patients with C HF, but only five met inclusion criteria for systematic review. Three repor ts described attention (total number of subjects = 369 patients and 882 con trols) and memory scores (total number of subjects = 247 patients and 748 c ontrols), two studies reported measures of general cognitive functioning (t otal number of subjects = 203 patients and 704 controls) and one reported t he rate of cognitive impairment (total number of subjects = 88 patients and 987 controls). Pooled analysis indicated that CHF is associated with a pat tern of generalized cognitive impairment that includes memory and attention deficits. Conclusions: The results of the present review highlight the enormous pauci ty of systematic information about the association between CHF and cognitiv e functioning, with only five studies reporting data suitable for analysis. We expect that new case-control and cohort studies will be designed to con firm the presence of cognitive impairment in patients with CHF and trust th at this information will improve the management of CHF patients and our und erstanding of the mechanisms associated with cognitive decline in later lif e.