Physical Activity and Risk of Hepatocellular Carcinoma: A Systematic Review and Meta-Analysis.

BACKGROUND & AIMS: Physical activity offers promise to protect against multiple non-hepatic primary cancers. We performed a systematic review to quantify the association between physical activity and hepatocellular carcinoma (HCC) risk. METHODS: We searched the Cochrane Library, Embase, Medline and trial registries through December 2020 for studies that measured physical activity levels in adults at risk for HCC. The primary outcome was HCC. Subgroup analysis was performed limiting to vigorous physical activity. Proportions and random-effects odds ratios (OR) with corresponding 95% confidence intervals (CI) were calculated. RESULTS: Seven studies met inclusion criteria, comprising 777,662 subjects (median age 55 years; 55% female). Greater amounts of physical activity were associated with less HCC (OR 0.65, 95% CI 0.45-0.95, p = 0.03) compared to lower amounts. Vigorous physical activity was associated with even less HCC (OR 0.62, 95% CI 0.49-0.79, p < 0.01). CONCLUSIONS: This meta-analysis demonstrates that greater amounts of physical activity are associated with lower odds of HCC. These results support the use of regular physical activity as an effective way to prevent HCC and provide helpful data to support a for future exercise-based interventional study to better define the optimal exercise prescription for patients at risk for primary liver cancer.

Physiologic Response to the Pfizer-BioNTech COVID-19 Vaccine Measured Using Wearable Devices: Prospective Observational Study.

BACKGROUND: The Pfizer-BioNTech COVID-19 vaccine uses a novel messenger RNA technology to elicit a protective immune response. Short-term physiologic responses to the vaccine have not been studied using wearable devices. OBJECTIVE: We aim to characterize physiologic changes in response to COVID-19 vaccination in a small cohort of participants using a wearable device (WHOOP Strap 3.0). This is a proof of concept for using consumer-grade wearable devices to monitor response to COVID-19 vaccines. METHODS: In this prospective observational study, physiologic data from 19 internal medicine residents at a single institution that received both doses of the Pfizer-BioNTech COVID-19 vaccine was collected using the WHOOP Strap 3.0. The primary outcomes were percent change from baseline in heart rate variability (HRV), resting heart rate (RHR), and respiratory rate (RR). Secondary outcomes were percent change from baseline in total, rapid eye movement, and deep sleep. Exploratory outcomes included local and systemic reactogenicity following each dose and prophylactic analgesic use. RESULTS: In 19 individuals (mean age 28.8, SD 2.2 years; n=10, 53% female), HRV was decreased on day 1 following administration of the first vaccine dose (mean -13.44%, SD 13.62%) and second vaccine dose (mean -9.25%, SD 22.6%). RHR and RR showed no change from baseline after either vaccine dose. Sleep duration was increased up to 4 days post vaccination, after an initial decrease on day 1. Increased sleep duration prior to vaccination was associated with a greater change in HRV. Local and systemic reactogenicity was more severe after dose two. CONCLUSIONS: This is the first observational study of the physiologic response to any of the novel COVID-19 vaccines as measured using wearable devices. Using this relatively small healthy cohort, we provide evidence that HRV decreases in response to both vaccine doses, with no significant changes in RHR or RR. Sleep duration initially decreased following each dose with a subsequent increase thereafter. Future studies with a larger sample size and comparison to other inflammatory and immune biomarkers such as antibody response will be needed to determine the true utility of this type of continuous wearable monitoring in regards to vaccine responses. Our data raises the possibility that increased sleep prior to vaccination may impact physiologic responses and may be a modifiable way to increase vaccine response. These results may inform future studies using wearables for monitoring vaccine responses. TRIAL REGISTRATION: ClinicalTrials.gov NCT04304703; https://www.clinicaltrials.gov/ct2/show/NCT04304703.

Exercise as Medicine: The Impact of Exercise Training on Nonalcoholic Fatty Liver Disease.

PURPOSE OF REVIEW: Nonalcoholic fatty liver disease (NAFLD) is a leading cause of global liver disease. Because current pharmacologic treatments are ineffective, lifestyle change centered on exercise remains the most effective NAFLD treatment. The aim of this systematic review is to summarize and evaluate the current evidence supporting the use of exercise training as a medical treatment for adult patients with NAFLD. RECENT FINDINGS: At least 150 minutes each week of moderate intensity exercise of any type can improve NAFLD, both with and without modest weight loss. Exercise training reduces hepatic steatosis and liver inflammation, favorably changes body composition, improves vascular endothelial function, increases cardiorespiratory fitness and can lead to histologic response. To date, exercise-based NAFLD trials are limited by small sample size and significant heterogeneity. SUMMARY: While several key questions remain unanswered, exercise training will always be an important part of the medical management of patients with NAFLD.