The clinical relevance of mild cognitive impairment in acute heart failure: A comparison with cognitive impairment

Background: Although mild cognitive impairment (MCI) has received much attention as a precursor of dementia, its prognostic role has not been fully clarified in patients with heart failure (HF). Methods and results: We studied 274 patients admitted for acute decompensated HF. Cognitive function was evaluated using Mini Mental State Examination (MMSE). According to the previous definition, MMSE of 0-23, 24-27, and 28-30 were classified as CI (n = 132), MCI (n = 81), and normal cognitive function (n = 61). The primary endpoint was cardiac events, defined as the composite of unplanned HF hospitalization and cardiovascular mortality. During a mean follow-up period of 4.9 +/- 3.1 years, 145 patients experienced cardiac events. Multivariable logistic regression analysis showed that hypertension (p = 0.043), low cardiac index (p = 0.022), and low serum albumin level (p = 0.041) had a significant association with cognitive abnormalities. Both CI and MCI were significantly associated with cardiac events after Cox multivariable adjustment [CI: p = 0.001, adjusted HR 2.66 (1.48-4.77); MCI: p = 0.025, adjusted HR 1.90 (1.09-3.31), normal cognitive function group: reference]. Patients with MCI had a significantly higher risk of unplanned HF hospitalization [p = 0.033, adjusted HR 1.91 (1.05-3.47)], but not all-cause mortality (p = 0.533) or cardiovascular mortality (p = 0.920), while CI was significantly associated with all-cause mortality (p = 0.025) and cardiovascular mortality (p = 0.036). Conclusion: Even MCI had a significant risk of cardiac events in patients with acute decompensated HF. This risk was mainly derived from unplanned HF hospitalization. (c) 2023 Japanese College of Cardiology. Published by Elsevier Ltd. This is an open access article under the CC BY -NC -ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).