Heart failure (HF) is a costly, chronic, and complex condition that impacts veterans' quality of life, morbidity, and mortality. In the VA population up to 20% of patients are readmitted for HF within 30 days. Non-adherence to prescribed medication and self-care regimens in patients with HF is known to lead to increased morbidity, including readmissions. Cognitive impairment (CI) has been shown to predict nonadherence in elderly people without HF, however, this link has not been studied in HF populations. In the non-veteran population, HF patients are known to have an increased prevalence of cognitive impairment (CI), however, no existing study has determined the extent and type of CI in veterans with HF.
This pilot study was designed as a descriptive cross-sectional study as a pre-implementation effort with following goals: (1) determine the prevalence of CI in veterans with all-cause HF in an outpatient setting; (2) quantitatively describe the extent of CI in this population; (3) qualitatively describe neuropsychological domains affected by CI; (4) evaluate the association of CI with medication adherence and other clinical variables.
All consenting eligible outpatients in our VA HF clinic underwent a simple screening test for CI (Saint Louis University Mental Status Exam). Demographic and clinical variables were collected by patient interviews and chart reviews, and included Geriatric Depression Scale and questionnaires about medication-taking behaviors. All subjects were invited back for 30-day direct pill-count of all their routinely prescribed medications. Subjects who screened positive for CI were invited back for a modified battery of neuropsychological tests to determine the cognitive domains affected. Subjects will also be followed after the 12-month study period to collect data on hospital readmissions.
In 251 study patients, we found a startlingly high prevalence of undiagnosed CI (59%), with 35% of those impaired scoring in the 'dementia' range. CI correlated with medication adherence (r=0.24, p=0.004). On average, patients in our study were taking 8 prescription medications, and made a mistake in 20% of their doses (either took too many or too few pills). Subjects were as likely to "overtake" as "undertake" their medications, making this a significant patient safety issue. Subjects completing the neuropsychological testing (n=88) had most impairment in the domains of immediate and delayed verbal memory .
This study showed that screening for CI in outpatients with HF is feasible, and that CI is prevalent in outpatients with HF, thus providing a target for interventions to improve outcomes in this population, including reduced readmissions. Based on this pilot data, we are designing a trial to assess the impact of an intervention targeted to improve adherence specifically in patients with CI and HF.
- Hawkins LA, Kilian S, Firek A, Kashner TM, Firek CJ, Silvet H. Cognitive impairment and medication adherence in outpatients with heart failure. Heart & lung : the journal of critical care. 2012 Nov 1; 41(6):572-82.