Hyponatremia, Cognitive Function, and Mobility in an Outpatient Heart Failure Population

Abstract

BackgroundThe association of hyponatremia with cognitive impairment and mobility in heart failure (HF) patients is unknown. The purpose of this study was to determine if hyponatremia is associated with cognitive and mobility impairment as measured by simple, validated, and time-sensitive tests.Material/MethodsThis was a prospective study in patients with reduced and preserved ejection fraction (HFrEF, HFpEF) seen in outpatient HF clinics. Hyponatremia was defined as sodium level ≤136 mEq/L. Cognitive function was measured using the Montreal Cognitive Assessment (MoCA) tool, and mobility was measured with the Timed Up and Go test (TUG-t).ResultsA total of 121 patients were evaluated; 30% were hyponatremic (134±1.9 mEq/l, range 128–136 mEq/l). Overall, 92% of hyponatremic patients had cognitive impairment (MoCA <26) compared to 76% of the non-hyponatremic patients [relative risk 1.2 (confidence interval: 1.02–1.4, p=0.02)]. In regard to mobility, 72% of hyponatremic patients and 62% of non-hyponatremic patients (p=0.4) had TUG-t times that were considered to be worse than average. A total of 84% (N=76) of HFrEF and 71% (N=22) of HFpEF patients had cognitive impairment (p=0.86). HFrEF patients had significantly lower overall MoCA scores (21.2±3.7 vs. 23.3±3.6, p=0.006) and similar TUG-t times compared to HFpEF patients.ConclusionsMost heart failure patients (HFrEF and HFpEF) seen in an ambulatory setting had impairment of cognitive function and mobility, with a higher prevalence among those with hyponatremia. Screening can be done using tests that can be administered in a clinical setting.

Soluble fibrin monomer complex is associated with cardio- and cerebrovascular events in patients with heart failure

“…HF patients have elevated levels of coagulation markers such as D-dimer [10] . Hypercoagulability in HF could be derived from many causes, such as blood stasis, hemodynamic disorders [36] , [37] , [38] , impaired cardiac structure and/or function, dilatation of cardiac chambers, reduced myocardial contractility, low cardiac output, mobility limitation [39] , increased intra-cardiac and central venous pressure, inflammation activation [40] , neuro-hormonal activation, impaired endothelial function, and arrhythmias such as AF [5] , [7] , [38] , [40] , [41] , [42] . The hypercoagulability status predisposes the patients to embolic events, and anticoagulation therapy could be associated with better clinical outcomes [11] .…”

Peak exercise stroke volume effects on cognitive impairment in community‐dwelling people with preserved ejection fraction

“…This study showed that peak VO 2 /HR is important in the pathophysiology of cognitive impairment compared with any other cognitive‐related potential factors (usual walking speed, TUG, aortic pulse wave velocity, and sarcopenia) among community‐dwelling older adults with preserved EF. Recently, a high prevalence of cognitive impairment was reported in patients with chronic HF (both HF with reduced and preserved EF). Interestingly, we found that peak VO 2 /HR is related to skeletal muscle mass index, which is an important factor in sarcopenia, and hypothesized that the decline of peak VO 2 /HR with decreased skeletal muscle mass in sarcopenia is a phenotype of HF with preserved EF .…”

“…Recently, chronic heart failure (HF) with both reduced and preserved ejection fraction (EF) has been associated with a high prevalence of cognitive impairment . Atrial fibrillation is a known risk factor for cognitive decline and dementia due to the attenuated ability to elevate cerebral perfusion during exercise because of the impaired ability to increase CO .…”

“…Recently, chronic heart failure (HF) with both reduced and preserved ejection fraction (EF) has been associated with a high prevalence of cognitive impairment. 11 Atrial fibrillation is a known risk factor for cognitive decline and dementia 12 due to the attenuated ability to elevate cerebral perfusion during exercise because of the impaired ability to increase CO. 13 Similarly, relationships between cognitive impairment and left ventricle EF, 14 left ventricle stroke volume (SV), and/or CO at rest have been demonstrated in communitydwelling people. 15 In addition, higher peak oxygen uptake (VO 2 ), which is known as peak CO during exercise, 16 is associated with better global cognitive function in communitydwelling people.…”

The relationship between serum uric acid and cognitive function in patients with chronic heart failure

“…Previous work has demonstrated that many medical comorbidities play an important role in the pathogenesis of cognitive impairment in CHF patients, including hypertension [9], type 2 diabetes mellitus [10], atrial fibrillation [11], obesity [12], chronic renal dysfunction [13], anemia [14], hyponatremia [15], depression [16], and sleep apnea [17]. However, the underlying mechanisms remain unclear.…”