“Obesity Paradox” Evident in the Relationship between Cognitive Function and Hospitalizations in Heart Failure Patients: A Pilot Study

Abstract

Heart failure (HF) is one of the leading causes of hospitalization and readmission. Given the chronicity of HF, it is critically important to identify risk factors for repeated hospitalizations. Both cognitive dysfunction and obesity are prevalent in HF, and each have been shown to independently be related to hospitalizations. However, while elevated body mass index (BMI) is linked to cognitive dysfunction in HF, how BMI and cognition interact to predict clinical endpoints in HF is unknown. We aimed to explore the retrospective association between BMI, cognitive performance, and 6-month hospitalization rates. As a part of a pilot program to incorporate cognitive and behavioral health screening into regular HF outpatient treatment, 28 participants completed the Montreal Cognitive Assessment (MoCA) and provided demographic and medical information during a routine cardiology visit. Number of inpatient hospitalizations over the previous 6 months was regressed on BMI, MoCA score, and their interaction, adjusting for age and severity of HF. The omnibus model significantly predicted hospitalization (F = 3.56, p = 0.02). The interaction of BMI and MoCA score was related to number of hospitalizations at a trend level (β = 0.016, t(20) = 1.8, p = 0.087), controlling for age and New York Heart Class. Participants with lower BMI demonstrated a negative association between cognitive performance and hospitalizations, such that lower cognitive function, is associated with a greater number of hospitalization in the prior six months. Participants with higher BMIs did not demonstrate this relationship between MoCA score and hospitalization. Our findings are consistent with research suggesting an “obesity paradox” among HF patients. It is unclear whether the interaction of BMI and cognitive dysfunction influences risk for hospitalization, or if hospitalization influences subsequent cognitive function, depending on BMI. Further research is necessary to explore predictors of hospitalizations prospectively. However, these data demonstrate the need for regular cognitive screening in the HF outpatient setting to ensure appropriate coordination of care.