Sedentary Time and Cumulative Risk of Preserved and Reduced Ejection Fraction Heart Failure: From the Multi-Ethnic Study of Atherosclerosis

Combined effect of left ventricular ejection fraction and obesity on sedentary behavior in patients with coronary artery disease

Sedentary behavior has been associated with poor adherence to treatment in patients with coronary artery disease. Low left ventricular ejection fraction and obesity have been separately linked to increased sedentary behavior in patients with coronary artery disease. However, the combined effect of low left ventricular ejection fraction and obesity on sedentary behavior in patients with coronary artery disease has not been thoroughly investigated. Therefore, this study aimed to examine the combined influence of left ventricular ejection fraction and obesity on sedentary behavior in patients with coronary artery disease. This descriptive cross-sectional study enrolled 200 inpatients aged ≥ 20 years who were diagnosed with coronary artery disease at a tertiary hospital in Korea between March and August 2022. Data were collected using structured questionnaires, and multivariate logistic regression analysis was performed to determine the combined effect of left ventricular ejection fraction and obesity on sedentary behavior in patients with coronary artery disease. Among the 111 patients with sedentary behavior, 38 (34.2%) had both low left ventricular ejection fraction and obesity, whereas only 11 (12.4%) of the 89 patients without sedentary behavior had both low left ventricular ejection fraction and obesity. In multivariate logistic regression analysis, patients with coronary artery disease who had both low left ventricular ejection fraction and obesity had the highest risk of sedentary behavior compared to those without either low left ventricular ejection fraction or obesity (odds ratio = 13.98, 95% confidence interval = 5.19-37.69, P < .001). The co-existence of low left ventricular ejection fraction and obesity in patients with coronary artery disease may be associated with sedentary behavior. Therefore, evaluating both left ventricular ejection fraction and obesity when assessing sedentary behavior in patients with coronary artery disease may be valuable in implementing patient-centered approaches for the secondary prevention and management of sedentary behavior in patients with coronary artery disease. However, further prospective cohort studies with larger sample sizes are required to establish causal relationships and explore interventions to mitigate sedentary behavior in this population.

Skeletal Muscle Mitochondrial Respiration and Exercise Intolerance in Patients With Heart Failure With Preserved Ejection Fraction

Importance

The pathophysiology of exercise intolerance in patients with heart failure with preserved ejection fraction (HFpEF) remains incompletely understood. Multiple lines of evidence suggest that abnormal skeletal muscle metabolism is a key contributor, but the mechanisms underlying metabolic dysfunction remain unresolved.

Objective

To evaluate the associations of skeletal muscle mitochondrial function using respirometric analysis of biopsied muscle fiber bundles from patients with HFpEF with exercise performance.

Design, Setting, and Participants

In this cross-sectional study, muscle fiber bundles prepared from fresh vastus lateralis biopsies were analyzed by high-resolution respirometry to provide detailed analyses of mitochondrial oxidative phosphorylation, including maximal capacity and the individual contributions of complex I-linked and complex II-linked respiration. These bioenergetic data were compared between patients with stable chronic HFpEF older than 60 years and age-matched healthy control (HC) participants and analyzed for intergroup differences and associations with exercise performance. All participants were treated at a university referral center, were clinically stable, and were not undergoing regular exercise or diet programs. Data were collected from March 2016 to December 2017, and data were analyzed from November 2020 to May 2021.

Main Outcomes and Measures

Skeletal muscle mitochondrial function, including maximal capacity and respiration linked to complex I and complex II. Exercise performance was assessed by peak exercise oxygen consumption, 6-minute walk distance, and the Short Physical Performance Battery.

Results

Of 72 included patients, 50 (69%) were women, and the mean (SD) age was 69.6 (6.1) years. Skeletal muscle mitochondrial function measures were all markedly lower in skeletal muscle fibers obtained from patients with HFpEF compared with HCs, even when adjusting for age, sex, and body mass index. Maximal capacity was strongly and significantly correlated with peak exercise oxygen consumption (R = 0.69; P < .001), 6-minute walk distance (R = 0.70; P < .001), and Short Physical Performance Battery score (R = 0.46; P < .001).

Conclusions and Relevance

In this study, patients with HFpEF had marked abnormalities in skeletal muscle mitochondrial function. Severely reduced maximal capacity and complex I-linked and complex II-linked respiration were associated with exercise intolerance and represent promising therapeutic targets.

Association of Sedentary Time and Incident Heart Failure Hospitalization in Postmenopausal Women

BACKGROUND

The 2018 US Physical Activity Guidelines recommend reducing sedentary behavior (SB) for cardiovascular health. SB's role in heart failure (HF) is unclear.

METHODS

We studied 80 982 women in the Women's Health Initiative Observational Study, aged 50 to 79 years, who were without known HF and reported ability to walk ≥1 block unassisted at baseline. Mean follow-up was 9 years for physician-adjudicated incident HF hospitalization (1402 cases). SB was assessed repeatedly by questionnaire. Time-varying total SB was categorized according to awake time spent sitting or lying down (≤6.5, 6.6-9.5, >9.5 h/d); sitting time (≤4.5, 4.6-8.5, >8.5 h/d) was also evaluated. Hazard ratios and 95% CI were estimated using Cox regression.

RESULTS

Controlling for age, race/ethnicity, education, income, smoking, alcohol, menopausal hormone therapy, and hysterectomy status, higher HF risk was observed across incremental tertiles of time-varying total SB (hazard ratios [95% CI], 1.00 [referent], 1.15 [1.01-1.31], 1.42 [1.25-1.61], trend P<0.001) and sitting time (1.00 [referent], 1.14 [1.01-1.28], 1.54 [1.34-1.78], trend P<0.001). The inverse trends remained significant after further controlling for comorbidities including time-varying myocardial infarction and coronary revascularization (hazard ratios: SB, 1.00, 1.11, 1.27; sitting, 1.00, 1.09, 1.37, trend P<0.001 each) and for baseline physical activity (hazard ratios: SB 1.00, 1.10, 1.24; sitting 1.00, 1.08, 1.33, trend P<0.001 each). Associations with SB exposures were not different according to categories of baseline age, race/ethnicity, body mass index, physical activity, physical functioning, diabetes, hypertension, or coronary heart disease.

CONCLUSIONS

SB was associated with increased risk of incident HF hospitalization in postmenopausal women. Targeted efforts to reduce SB could enhance HF prevention in later life.

Associated factors and impacts of sedentary behaviour in patients with heart failure: A longitudinal study

BACKGROUND

Sedentary behaviours may be related to factors such as self-efficacy, mood and social support. However, there is a paucity of longitudinal follow-up studies examining factors related to sedentary behaviour from physical-psychosocial perspectives in patients with heart failure.

AIMS

The purpose of this study was to explore the multidimensional associated factors and impacts of sedentary behaviour in heart failure patients.

METHODS

A longitudinal design was used. A convenience sample of 128 heart failure patients recruited from two large medical centres in northern Taiwan was obtained. Patients were interviewed with structured questionnaires to assess physical activity, symptom distress, exercise self-efficacy, anxiety and depression, social support, sleep quality and quality of life before discharge and at 3 and 6 months after discharge.

RESULTS

Heart failure patients reported low physical activity and tended to be sedentary. Sedentary behaviour was gradually reduced from hospitalization to 6 months after discharge. Sleep quality, quality of life, analgesic use, symptom distress and exercise self-efficacy were significant associated factors that explained 42.1-51% of the variance in sedentary behaviour. Patients with high sedentary behaviour had significantly greater depression and poorer sleep and quality of life than those with low sedentary behaviour at hospitalization and showed a significant improvement in depression at 3 and 6 months after discharge.

CONCLUSION

Sedentary behaviour is common in heart failure patients and has impacts on depression and quality of life. An appropriate physical activity programme focusing on disease self-management and enhancing self-efficacy is needed for heart failure patients to improve their sedentary behaviour and quality of life.

Objectively-Measured Light-Intensity Physical Activity and Risk of Cancer Mortality: A Meta-analysis of Prospective Cohort Studies

BACKGROUND

The impact of light-intensity physical activity (LPA) in preventing cancer mortality has been questioned. To address this concern, the present meta-analysis aimed to quantify the association between objectively-measured LPA and risk of cancer mortality.

METHODS

We conducted a systematic literature search in PubMed and Scopus to January 2020. Prospective cohort studies reporting the association between objectively-measured LPA using activity monitors (e.g., accelerometers) and risk of cancer mortality in the general population were included. The summary hazard ratios (HR) per 30 min/day of LPA and 95% confidence intervals (CI) were obtained using a random-effects model. Dose-response analysis was used to plot their relationship.

RESULTS

Five prospective cohort studies were included, in which the definition of LPA based on accelerometer readings was mainly set within 100 to 2,100 counts/min. The summary HR for cancer mortality per 30 min/day of LPA was 0.86 (95% CI, 0.79-0.95; I ² < 1%), and the association between LPA and risk reduction in cancer mortality was linearly shaped (P _nonlinearity = 0.72). LPA exhibited a comparable magnitude of risk reduction in cancer mortality of moderate-to-vigorous physical activity regardless of equal time-length (0.87 per 30 min/day vs. 0.94 per 30 min/day, P _interaction = 0.46) or equal amount (0.74 vs. 0.94 per 150 metabolic equivalents-min/day, P _interaction = 0.11). Furthermore, replacing sedentary time by LPA of 30 min/day decreased the risk of cancer mortality by 9%.

CONCLUSIONS

Objectively-measured LPA conferred benefits in decreasing the risk of cancer mortality.

IMPACT

LPA should be considered in physical activity guidelines to decrease the risk of cancer mortality.

Sarcopenic Obesity in Heart Failure With Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is a public health epidemic that is projected to double over the next two decades. Despite the high prevalence of HFpEF, there are currently no FDA approved therapies for health-related outcomes in this clinical syndrome making it one the greatest unmet needs in cardiovascular medicine. Aging and obesity are hallmarks of HFpEF and therefore there is a high incidence of sarcopenic obesity (SO) associated with this syndrome. The presence of SO in HFpEF patients is noteworthy as it is associated with co-morbidities, worsened cardiovascular health, hospitalizations, quality of life, and mortality. Furthermore, SO plays a central role in exercise intolerance, the most commonly reported clinical symptom of this condition. The aim of this review is to provide insights into the current knowledge pertaining to the contributing pathophysiological mechanisms and clinical outcomes associated with HFpEF-related SO. Current and prospective therapies to address SO in HFpEF, including lifestyle and pharmaceutical approaches, are discussed. The urgent need for future research aimed at better understanding the multifaceted physiological contributions to SO in HFpEF and implementing interventional strategies to specifically target SO is highlighted.