The Prevalence of Cognitive Impairment among African-American Patients with Congestive Heart Failure Abimbola Akomolafe, MD, MPH, MSc; Alexander Quarshie, MD, MS; Patricia Jackson, RN; Jerome Thomas, MD; Orlando Deffer, MD; Adefisayo Oduwole, MD; Anekwe Onwuanyi, MD; Rigobert Lapu-Bula, MD, PhD; Gregory Strayhorn, MD, PhD; Elizabeth Ofili, MD, MPH; and Robert Mayberry, MPH, PhD Atlanta, Georgia Financial support: This project was supported in part by grant number P01 HS10875 from the Agency for Healthcare Research and Quality for the Program for Healthcare Effectiveness Research and grant numbers P20RR 11 104, (CRC) 5P20RR1 104-09 and (CCRE) U54RR14758-05 for the MSM Clinical Research Center from the National Institutes of Health, National Center for Research Resources (NCRR). This cross-seclional study sought to determine the prevalence of cognitive impairment among African-American patients with congestive heart failure (CHF). We studied 100 AfrcanAmerican CHF patients (aged 55-87 years) in New York Heart Association classes II-IV, who are enrolled in an ongoing, randomized, controlled tral, evaluating the effectiveness of a telemonitoring intervention to improve access to ambulatory care for heart failure patients. These CHF patients were recruited from an inner-city practice, rural physician practices and an urban physician practice in Atlanta. The Mini-Mental Status Examination (MMSE) was used to measure cognifion. Cognitive impairment was defined as a MMSE score of less than 24. The crude prevalence of cognitive impairment was 10%o in this population of African Americans with CHF. The results of multivariate logistic regression analysis indicated an increase in odds of cognitive impairment with increasing age [odds ratio (OR) = 1.10 and 95% confidence interval, 1.00-1.20; p=0.042]. There was no significant relationship between cognitive impairment and gender, education status, depression and severity of CHF. This study indicates that cognitive impairment is relatively prevalent among African Americans with CHF, but lower than previously reported among Caucasians with CHF. Key words: cognitive impairment a African Amercans U congestive * heart failure © 2005. From the Department of Medicine, Clinical Research Center and Department of Family Medicine, Morehouse School of Medicine, Atlanta, GA. Send correspondence and reprnt requests for J Natl Med Assoc. 2005;97:689-694 to: Abimbola Akomolafe, MD, MPH, MSc, Department of Medicine, Section of Geri atrics, Morehouse School of Medicine, 720 Westview Ddve SW, Atlanta, GA 30310; phone: (404) 756-1330; fax: (404) 756-1328; e-mail:
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JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION
INTRODUCTION Congestive heart failure (CHF) is a major public health problem affecting over 4.7 million Americans and 15 million people worldwide.' More than 550,000 new cases occur annually in the United States.'-3 Approximately 1.5-2% of the population has CHF, and the prevalence increases to 6-10% in patients 65 years and over.4-6 CHF is a major cause of morbidity and mortality among older people in Western countries.7 It is the leading indication for hospital admission in adults older than age 65.8 Among factors related to rehospitalization are nonadherence to medication and advice on lifestyle modifications, as well as failure to seek medical attention when the condition deteriorates.9-'l Despite advances in pharmacological treatment, the prognosis of older patients hospitalized for heart failure is poor, with one-month posthospitalization mortality exceeding 25% and one-year mortality greater than 50% in persons age 85 years and above.'2"'3 Although normal aging is not necessarily associated with diminished cognitive function, up to 17% of those aged 65 years and older do experience at least mild-to-moderate decreases in cognitive function, especially those related to memory, which are not related to dementia of either the vascular or Alzheimer's type.'4"5 Cognitive impairment is rapidly becoming a public health problem, and it shows a strong association with dependency,'6 morbidity'7 and mortality.'8 Decrease in cognitive function has been reported in patients with a variety of cardiovascular conditions.'9'20 There is increasing evidence that CHF is independently associated with cognitive impairment.2'-23 "Cardiogenic" or "circulatory" dementia24'25 has been proposed to explain cognitive impairment in these patients. CHF and cognitive impairment are both associated with increased mortality,26 disability,27 decreased quality of life28 and spousal and caregiver distress.29 VOL. 97, NO. 5, MAY 2005 689
COGNITIVE IMPAIRMENT AND CONGESTIVE HEART FAILURE
Our search of the medical literature highlighted the paucity of data on the prevalence of cognitive impairment among CHF patients, especially in the AfricanAmerican population.30 The above-referenced study indicated that African Americans were found to go home much sicker, more dependent and more cognitively impaired than their white counterparts. Because CHF disproportionately affects African Americans and the incidence and prevalence ofthis disease is higher in this population of patients than other racial groups,31 the high prevalence of cognitive impairment among this group of patients could have clinical and public health implications. Therefore, the present study sought to assess the prevalence of cognitive impairment among African-American patients with CHF.
METHODS This cross-sectional sample was drawn from patients who were consecutively recruited for an ongoing, single-blinded, randomized, controlled trial evaluating the effectiveness of a telemonitoring, patient-oriented intervention to improve access to ambulatory care for heart failure patients. Eligible study subjects were African-American CHF patients, 55 years of age and older in New York Heart Associa-
tion (NYHA) classes II-IV, attending the inner-city practice (Grady Hospital and ambulatory clinic); rural counties surrounding Columbus, GA; and urban practice in metropolitan Atlanta. Patients were included if they had a primary diagnosis of heart failure (International Classification of Disease-9 code 428.0), NYHA severity index II and greater and were at high risk for readmission as measured by one of the following: a) patients who are within two weeks of a hospital discharge for heart failure and who had at least one heart failure hospitalization in the preceding six months; b) at least two emergency room visits over two months for heart failure exacerbation; and c) excessive office visits for heart failure exacerbation as documented by the primary physician (at least two such visits over two months were required for study entry). Patients with a confirmed diagnosis of CHF were excluded from this study for the following reasons: 1) hemodynamic instability, or need for inpatient or intensive-care unit monitoring; 2) uncooperative or combative patient; 3) patient in long-term facility; 4) advanced dementia or psychiatric illness; 5) refusal to participate by the patient or physician; and 6) inability to obtain informed consent. The diagnosis of CHF was confirmed when at least one of the fol-
Table 1. Characteristics of the Study Population (n=100) and Association with Cognitive Impairment All Subjects P Value Characteristic Cognitive Impairment n (%) Yes (n=10) No (n=90) Age n (%) n (%) 2 (20.00) 75 years 22 (22.00) 5 (50.00) 17 (18.89) 0.074
Gender Females Males
64 36
(64.00) (36.00)
4 (40.00) 6 (60.00)
60 (66.67) 30 (33.33)
0.096
Depression
76 23
(76.00) (23.00)
8 (80.00) 2 (20.00)
69 (76.67) 21 (23.33)
0.812
Education 40
