Applied nutritional investigationFunctional status and heart rate variability in end-stage liver disease patients: Association with nutritional status

- Functional status is related to cardiac risk in malnourished patients with liver disease.
- The 6-minute walk test and heart rate variability is a potential tool to screen cardiac risk in this population
- The cardiac workload index is negatively associated to lower gait speed (6-minute walk test) and lower heart rate variability.

ObjectivesMuscle dysfunction and reduced heart rate variability (HRV) are common in patients with advanced liver disease, and both are related to poor outcomes. Malnutrition is also highly prevalent in these patients, however, the association between the malnutrition and HRV has not yet been assessed. The aim of this study was to evaluate the short-term HRV, functional and nutritional statuses in patients with advanced liver disease.MethodsThe nutritional and functional statuses were determined by subjective global assessment, handgrip strength (dynamometer, JAMAR) and gait speed during a 6-minute walk text (6MWT), respectively. The cardiac workload index (CWI) was used to evaluate the cardiac response to the 6MWT. The time domain (SD of all normal-to-normal intervals [SDNN]) and very-low, low-, and high-frequency domains of short-term HRV were evaluated with RS800 CX (Polar, Finland) and Cardioseries software (Brazil).ResultsThe study evaluated 42 patients with liver disease (62% men) and malnutrition was found in 62% of this population. The malnourished participants presented with reduced functional status, 41% decreased SDNN, and 14% greater CWI compared with well-nourished individuals (P < 0.05). Additionally, the CWI was negatively associated to SDNN (r = 0.414; P < 0.05) and gait speed (r = 0.598; P < 0.05), especially in malnourished individuals (r = 0.650; P < 0.05). These data indicate that malnourished patients with liver disease have higher cardiovascular risk related to reduced functional status, which may be associated to poor outcomes during the course of the disease before and after transplant. Another relevant aspect is that the 6MWT associated to HRV could be a useful tool to screen liver disease patients who have a higher risk for cardiovascular complications.