Objective Versus Subjective Assessment of Functional Status in Candidates for Liver Transplantation

Exercise physiology in cirrhosis and the potential benefits of exercise interventions: A review

Reduction in muscle mass is a highly prevalent phenomenon in cirrhosis and is now well-documented to be associated with significant morbidity and mortality. Research into muscle loss in cirrhosis remains limited by an ongoing poor understanding of its relationship with muscle function, physical activity, and aerobic capacity. Alterations in exercise physiology have been documented in studies of individuals with cirrhosis that provide important information on physical function that is not captured by simple quantification of muscle mass. Despite expert consensus recommending regular exercise in end-stage liver disease to maintain muscle mass and function, there is little evidence guiding clinicians as to which form of exercise or delivery mechanism is most effective. It also remains unproven whether any specific intervention can alter clinically relevant outcomes. This review article summarizes the available literature regarding the changes in exercise physiology observed in cirrhosis, the associated impact on physical capacity, and the results of existing trials that examine the potential benefits of exercise delivery in patients with cirrhosis, particularly pertaining to their impact on exercise physiology.

Sleep and functional capacity in adults: Cross-sectional associations among self-report and objective assessments

OBJECTIVES

This study examined the relationship between self-reported and objectively measured sleep and functional capacity in adults.

DESIGN

Cross-sectional.

PARTICIPANTS

Data were from the Midlife in the United States study. The sample consisted of men and women (n = 664) aged 25-83 who completed telephone interviews, questionnaires, and an overnight clinic stay.

MEASUREMENTS

Sleep was assessed by self-report (Pittsburgh Sleep Quality Index [PSQI]) and by objective measures (sleep latency, duration, wake after sleep onset [WASO], and midpoint/midpoint variability) from 7 consecutive days of actigraphy. Functional capacity was assessed by self-report of limitations and measured gait speed, grip strength, and chair stands.

RESULTS

In linear regression models adjusting for demographic and health factors, better self-reported sleep quality predicted fewer reported limitations, stronger grip, quicker gait, and faster chair stands (all P< .01). Greater WASO predicted more self-report limitations and slower gait speed (P< .05). Long (>8 hours) sleep duration and a more variable sleep schedule predicted lower grip strength (p < .05). Finally, after adjustment for objective sleep measures, PSQI remained a significant predictor of functional measures (P< .05) and explained a significant amount of additional variance (change in R²: 0.01-0.05).

CONCLUSIONS

The present results suggest that subjective and objective sleep measures capture distinct aspects of sleep that are independently related to functional capacity. The variance in functional measures explained by sleep variables, though small, was comparable to other risk factors for functional impairment (eg, obesity), underscoring the importance of associations between sleep and optimal function in adults.

Evaluating the Associations Between the Liver Frailty Index and Karnofsky Performance Status With Waitlist Mortality

Frailty has emerged as a critical determinant of mortality in patients with cirrhosis. Currently, the United Network for Organ Sharing registry only includes the Karnofsky Performance Status (KPS) scale, which captures a single component of frailty. We determined the associations between frailty, as measured by the Liver Frailty Index (LFI), and KPS with waitlist mortality.