Exercise-based cardiac rehabilitation for coronary heart disease: a meta-analysis.

AIMS: Coronary heart disease is the most common reason for referral to exercise-based cardiac rehabilitation (CR) globally. However, the generalizability of previous meta-analyses of randomized controlled trials (RCTs) is questioned. Therefore, a contemporary updated meta-analysis was undertaken. METHODS AND RESULTS: Database and trial registry searches were conducted to September 2020, seeking RCTs of exercise-based interventions with ≥6-month follow-up, compared with no-exercise control for adults with myocardial infarction, angina pectoris, or following coronary artery bypass graft, or percutaneous coronary intervention. The outcomes of mortality, recurrent clinical events, and health-related quality of life (HRQoL) were pooled using random-effects meta-analysis, and cost-effectiveness data were narratively synthesized. Meta-regression was used to examine effect modification. Study quality was assessed using the Cochrane risk of bias tool. A total of 85 RCTs involving 23 430 participants with a median 12-month follow-up were included. Overall, exercise-based CR was associated with significant risk reductions in cardiovascular mortality [risk ratio (RR): 0.74, 95% confidence interval (CI): 0.64-0.86, number needed to treat (NNT): 37], hospitalizations (RR: 0.77, 95% CI: 0.67-0.89, NNT: 37), and myocardial infarction (RR: 0.82, 95% CI: 0.70-0.96, NNT: 100). There was some evidence of significantly improved HRQoL with CR participation, and CR is cost-effective. There was no significant impact on overall mortality (RR: 0.96, 95% CI: 0.89-1.04), coronary artery bypass graft (RR: 0.96, 95% CI: 0.80-1.15), or percutaneous coronary intervention (RR: 0.84, 95% CI: 0.69-1.02). No significant difference in effects was found across different patient groups, CR delivery models, doses, follow-up, or risk of bias. CONCLUSION: This review confirms that participation in exercise-based CR by patients with coronary heart disease receiving contemporary medical management reduces cardiovascular mortality, recurrent cardiac events, and hospitalizations and provides additional evidence supporting the improvement in HRQoL and the cost-effectiveness of CR.

Adolescents' interactive electronic device use, sleep and mental health: a systematic review of prospective studies.

Optimal sleep, both in terms of duration and quality, is important for adolescent health. However, young people's sleeping habits have worsened over recent years. Access to and use of interactive electronic devices (e.g., smartphones, tablets, portable gaming devices) and social media have become deep-rooted elements of adolescents' lives and are associated with poor sleep. Additionally, there is evidence of increases in poor mental health and well-being disorders in adolescents; further linked to poor sleep. This review aimed to summarise the longitudinal and experimental evidence of the impact of device use on adolescents' sleep and subsequent mental health. Nine electronic bibliographical databases were searched for this narrative systematic review in October 2022. Of 5779 identified unique records, 28 studies were selected for inclusion. A total of 26 studies examined the direct link between device use and sleep outcomes, and four reported the indirect link between device use and mental health, with sleep as a mediator. The methodological quality of the studies was generally poor. Results demonstrated that adverse implications of device use (i.e., overuse, problematic use, telepressure, and cyber-victimisation) impacted sleep quality and duration; however, relationships with other types of device use were unclear. A small but consistent body of evidence showed sleep mediates the relationship between device use and mental health and well-being in adolescents. Increasing our understanding of the complexities of device use, sleep, and mental health in adolescents are important contributions to the development of future interventions and guidelines to prevent or increase resilience to cyber-bullying and ensure adequate sleep.

Social network interventions to support cardiac rehabilitation and secondary prevention in the management of people with heart disease.

BACKGROUND: Globally, cardiovascular diseases (CVD, that is, coronary heart (CHD) and circulatory diseases combined) contribute to 31% of all deaths, more than any other cause. In line with guidance in the UK and globally, cardiac rehabilitation programmes are widely offered to people with heart disease, and include psychosocial, educational, health behaviour change, and risk management components. Social support and social network interventions have potential to improve outcomes of these programmes, but whether and how these interventions work is poorly understood.  OBJECTIVES: To assess the effectiveness of social network and social support interventions to support cardiac rehabilitation and secondary prevention in the management of people with heart disease. The comparator was usual care with no element of social support (i.e. secondary prevention alone or with cardiac rehabilitation).  SEARCH METHODS: We undertook a systematic search of the following databases on 9 August 2022: CENTRAL, MEDLINE, Embase, and the Web of Science. We also searched ClinicalTrials.gov and the WHO ICTRP. We reviewed the reference lists of relevant systematic reviews and included primary studies, and we contacted experts to identify additional studies.  SELECTION CRITERIA: We included randomised controlled trials (RCTs) of social network or social support interventions for people with heart disease. We included studies regardless of their duration of follow-up, and included those reported as full text, published as abstract only, and unpublished data. DATA COLLECTION AND ANALYSIS: Using Covidence, two review authors independently screened all identified titles. We retrieved full-text study reports and publications marked 'included', and two review authors independently screened these, and conducted data extraction. Two authors independently assessed risk of bias, and assessed the certainty of the evidence using GRADE. Primary outcomes were all-cause mortality, cardiovascular-related mortality, all-cause hospital admission, cardiovascular-related hospital admission, and health-related quality of life (HRQoL) measured at > 12 months follow-up.  MAIN RESULTS: We included 54 RCTs (126 publications) reporting data for a total of 11,445 people with heart disease. The median follow-up was seven months and median sample size was 96 participants. Of included study participants, 6414 (56%) were male, and the mean age ranged from 48.6 to 76.3 years. Studies included heart failure (41%), mixed cardiac disease (31%), post-myocardial infarction (13%), post-revascularisation (7%), CHD (7%), and cardiac X syndrome (1%) patients. The median intervention duration was 12 weeks. We identified notable diversity in social network and social support interventions, across what was delivered, how, and by whom.  We assessed risk of bias (RoB) in primary outcomes at > 12 months follow-up as either 'low' (2/15 studies), 'some concerns' (11/15), or 'high' (2/15). 'Some concerns' or 'high' RoB resulted from insufficient detail on blinding of outcome assessors, data missingness, and absence of pre-agreed statistical analysis plans. In particular, HRQoL outcomes were at high RoB. Using the GRADE method, we assessed the certainty of evidence as low or very low across outcomes. Social network or social support interventions had no clear effect on all-cause mortality (risk ratio (RR) 0.75, 95% confidence interval (CI) 0.49 to 1.13, I2 = 40%) or cardiovascular-related mortality (RR 0.85, 95% CI 0.66 to 1.10, I2 = 0%) at > 12 months follow-up. The evidence suggests that social network or social support interventions for heart disease may result in little to no difference in all-cause hospital admission (RR 1.03, 95% CI 0.86 to 1.22, I2 = 0%), or cardiovascular-related hospital admission (RR 0.92, 95% CI 0.77 to 1.10, I2 = 16%), with a low level of certainty. The evidence was very uncertain regarding the impact of social network interventions on HRQoL at > 12 months follow-up (SF-36 physical component score: mean difference (MD) 31.53, 95% CI -28.65 to 91.71, I2 = 100%, 2 trials/comparisons, 166 participants; mental component score MD 30.62, 95% CI -33.88 to 95.13, I2 = 100%, 2 trials/comparisons, 166 participants).  Regarding secondary outcomes, there may be a decrease in both systolic and diastolic blood pressure with social network or social support interventions. There was no evidence of impact found on psychological well-being, smoking, cholesterol, myocardial infarction, revascularisation, return to work/education, social isolation or connectedness, patient satisfaction, or adverse events.  Results of meta-regression did not suggest that the intervention effect was related to risk of bias, intervention type, duration, setting, and delivery mode, population type, study location, participant age, or percentage of male participants.  AUTHORS' CONCLUSIONS: We found no strong evidence for the effectiveness of such interventions, although modest effects were identified in relation to blood pressure. While the data presented in this review are indicative of potential for positive effects, the review also highlights the lack of sufficient evidence to conclusively support such interventions for people with heart disease. Further high-quality, well-reported RCTs are required to fully explore the potential of social support interventions in this context. Future reporting of social network and social support interventions for people with heart disease needs to be significantly clearer, and more effectively theorised, in order to ascertain causal pathways and effect on outcomes.

Exercise-based cardiac rehabilitation for coronary heart disease.

BACKGROUND: Coronary heart disease (CHD) is the most common cause of death globally. However, with falling CHD mortality rates, an increasing number of people living with CHD may need support to manage their symptoms and prognosis. Exercise-based cardiac rehabilitation (CR) aims to improve the health and outcomes of people with CHD. This is an update of a Cochrane Review previously published in 2016. OBJECTIVES: To assess the clinical effectiveness and cost-effectiveness of exercise-based CR (exercise training alone or in combination with psychosocial or educational interventions) compared with 'no exercise' control, on mortality, morbidity and health-related quality of life (HRQoL) in people with CHD. SEARCH METHODS: We updated searches from the previous Cochrane Review, by searching CENTRAL, MEDLINE, Embase, and two other databases in September 2020. We also searched two clinical trials registers in June 2021. SELECTION CRITERIA: We included randomised controlled trials (RCTs) of exercise-based interventions with at least six months' follow-up, compared with 'no exercise' control. The study population comprised adult men and women who have had a myocardial infarction (MI), coronary artery bypass graft (CABG) or percutaneous coronary intervention (PCI), or have angina pectoris, or coronary artery disease. DATA COLLECTION AND ANALYSIS: We screened all identified references, extracted data and assessed risk of bias according to Cochrane methods. We stratified meta-analysis by duration of follow-up: short-term (6 to 12 months); medium-term (> 12 to 36 months); and long-term ( > 3 years), and used meta-regression to explore potential treatment effect modifiers. We used GRADE for primary outcomes at 6 to 12 months (the most common follow-up time point).  MAIN RESULTS: This review included 85 trials which randomised 23,430 people with CHD. This latest update identified 22 new trials (7795 participants). The population included predominantly post-MI and post-revascularisation patients, with a mean age ranging from 47 to 77 years. In the last decade, the median percentage of women with CHD has increased from 11% to 17%, but females still account for a similarly small percentage of participants recruited overall ( < 15%). Twenty-one of the included trials were performed in low- and middle-income countries (LMICs). Overall trial reporting was poor, although there was evidence of an improvement in quality over the last decade. The median longest follow-up time was 12 months (range 6 months to 19 years). At short-term follow-up (6 to 12 months), exercise-based CR likely results in a slight reduction in all-cause mortality (risk ratio (RR) 0.87, 95% confidence interval (CI) 0.73 to 1.04; 25 trials; moderate certainty evidence), a large reduction in MI (RR 0.72, 95% CI 0.55 to 0.93; 22 trials; number needed to treat for an additional beneficial outcome (NNTB) 75, 95% CI 47 to 298; high certainty evidence), and a large reduction in all-cause hospitalisation (RR 0.58, 95% CI 0.43 to 0.77; 14 trials;  NNTB 12, 95% CI 9 to 21; moderate certainty evidence). Exercise-based CR likely results in little to no difference in risk of cardiovascular mortality (RR 0.88, 95% CI 0.68 to 1.14; 15 trials; moderate certainty evidence), CABG (RR 0.99, 95% CI 0.78 to 1.27; 20 trials; high certainty evidence), and PCI (RR 0.86, 95% CI 0.63 to 1.19; 13 trials; moderate certainty evidence) up to 12 months' follow-up. We are uncertain about the effects of exercise-based CR on cardiovascular hospitalisation, with a wide confidence interval including considerable benefit as well as harm (RR 0.80, 95% CI 0.41 to 1.59; low certainty evidence). There was evidence of substantial heterogeneity across trials for cardiovascular hospitalisations (I2 = 53%), and of small study bias for all-cause hospitalisation, but not for all other outcomes. At medium-term follow-up, although there may be little to no difference in all-cause mortality (RR 0.90, 95% CI 0.80 to 1.02; 15 trials), MI (RR 1.07, 95% CI 0.91 to 1.27; 12 trials), PCI (RR 0.96, 95% CI 0.69 to 1.35; 6 trials), CABG (RR 0.97, 95% CI 0.77 to 1.23; 9 trials), and all-cause hospitalisation (RR 0.92, 95% CI 0.82 to 1.03; 9 trials), a large reduction in cardiovascular mortality was found (RR 0.77, 95% CI 0.63 to 0.93; 5 trials). Evidence is uncertain for difference in risk of cardiovascular hospitalisation (RR 0.92, 95% CI 0.76 to 1.12; 3 trials). At long-term follow-up, although there may be little to no difference in all-cause mortality (RR 0.91, 95% CI 0.75 to 1.10), exercise-based CR may result in a large reduction in cardiovascular mortality (RR 0.58, 95% CI 0.43 to 0.78; 8 trials) and MI (RR 0.67, 95% CI 0.50 to 0.90; 10 trials). Evidence is uncertain for CABG (RR 0.66, 95% CI 0.34 to 1.27; 4 trials), and PCI (RR 0.76, 95% CI 0.48 to 1.20; 3 trials). Meta-regression showed benefits in outcomes were independent of CHD case mix, type of CR, exercise dose, follow-up length, publication year, CR setting, study location, sample size or risk of bias. There was evidence that exercise-based CR may slightly increase HRQoL across several subscales (SF-36 mental component, physical functioning, physical performance, general health, vitality, social functioning and mental health scores) up to 12 months' follow-up; however, these may not be clinically important differences. The eight trial-based economic evaluation studies showed exercise-based CR to be a potentially cost-effective use of resources in terms of gain in quality-adjusted life years (QALYs). AUTHORS' CONCLUSIONS: This updated Cochrane Review supports the conclusions of the previous version, that exercise-based CR provides important benefits to people with CHD, including reduced risk of MI, a likely small reduction in all-cause mortality, and a large reduction in all-cause hospitalisation, along with associated healthcare costs, and improved HRQoL up to 12 months' follow-up. Over longer-term follow-up, benefits may include reductions in cardiovascular mortality and MI. In the last decade, trials were more likely to include females, and be undertaken in LMICs, increasing the generalisability of findings. Well-designed, adequately-reported RCTs of CR in people with CHD more representative of usual clinical practice are still needed. Trials should explicitly report clinical outcomes, including mortality and hospital admissions, and include validated HRQoL outcome measures, especially over longer-term follow-up, and assess costs and cost-effectiveness.

Evidence for exercise-based interventions across 45 different long-term conditions: an overview of systematic reviews.

Background: Almost half of the global population face significant challenges from long-term conditions (LTCs) resulting in substantive health and socioeconomic burden. Exercise is a potentially key intervention in effective LTC management. Methods: In this overview of systematic reviews (SRs), we searched six electronic databases from January 2000 to October 2023 for SRs assessing health outcomes (mortality, hospitalisation, exercise capacity, disability, frailty, health-related quality of life (HRQoL), and physical activity) related to exercise-based interventions in adults (aged >18 years) diagnosed with one of 45 LTCs. Methodological quality was assessed using AMSTAR-2. International Prospective Resister of Systematic Reviews (PROSPERO) ID: CRD42022319214. Findings: Forty-two SRs plus three supplementary RCTs were included, providing 990 RCTs in 936,825 people across 39 LTCs. No evidence was identified for six LTCs. Predominant outcome domains were HRQoL (82% of SRs/RCTs) and exercise capacity (66%); whereas disability, mortality, physical activity, and hospitalisation were less frequently reported (≤25%). Evidence supporting exercise-based interventions was identified in 25 LTCs, was unclear for 13 LTCs, and for one LTC suggested no effect. No SRs considered multimorbidity in the delivery of exercise. Methodological quality varied: critically-low (33%), low (26%), moderate (26%), and high (12%). Interpretation: Exercise-based interventions improve HRQoL and exercise capacity across numerous LTCs. Key evidence gaps included limited mortality and hospitalisation data and consideration of multimorbidity impact on exercise-based interventions. Funding: This study was funded by the National Institute for Health and Care Research (NIHR; Personalised Exercise-Rehabilitation FOR people with Multiple long-term conditions (multimorbidity)-NIHR202020).

Association of latent class analysis-derived multimorbidity clusters with adverse health outcomes in patients with multiple long-term conditions: comparative results across three UK cohorts.

Background: It remains unclear how to meaningfully classify people living with multimorbidity (multiple long-term conditions (MLTCs)), beyond counting the number of conditions. This paper aims to identify clusters of MLTCs in different age groups and associated risks of adverse health outcomes and service use. Methods: Latent class analysis was used to identify MLTCs clusters in different age groups in three cohorts: Secure Anonymised Information Linkage Databank (SAIL) (n = 1,825,289), UK Biobank (n = 502,363), and the UK Household Longitudinal Study (UKHLS) (n = 49,186). Incidence rate ratios (IRR) for MLTC clusters were computed for: all-cause mortality, hospitalisations, and general practice (GP) use over 10 years, using <2 MLTCs as reference. Information on health outcomes and service use were extracted for a ten year follow up period (between 01st Jan 2010 and 31st Dec 2019 for UK Biobank and UKHLS, and between 01st Jan 2011 and 31st Dec 2020 for SAIL). Findings: Clustering MLTCs produced largely similar results across different age groups and cohorts. MLTC clusters had distinct associations with health outcomes and service use after accounting for LTC counts, in fully adjusted models. The largest associations with mortality, hospitalisations and GP use in SAIL were observed for the "Pain+" cluster in the age-group 18-36 years (mortality IRR = 4.47, hospitalisation IRR = 1.84; GP use IRR = 2.87) and the "Hypertension, Diabetes & Heart disease" cluster in the age-group 37-54 years (mortality IRR = 4.52, hospitalisation IRR = 1.53, GP use IRR = 2.36). In UK Biobank, the "Cancer, Thyroid disease & Rheumatoid arthritis" cluster in the age group 37-54 years had the largest association with mortality (IRR = 2.47). Cardiometabolic clusters across all age groups, pain/mental health clusters in younger groups, and cancer and pulmonary related clusters in older age groups had higher risk for all outcomes. In UKHLS, MLTC clusters were not significantly associated with higher risk of adverse outcomes, except for the hospitalisation in the age-group 18-36 years. Interpretation: Personalising care around MLTC clusters that have higher risk of adverse outcomes may have important implications for practice (in relation to secondary prevention), policy (with allocation of health care resources), and research (intervention development and targeting), for people living with MLTCs. Funding: This study was funded by the National Institute for Health and Care Research (NIHR; Personalised Exercise-Rehabilitation FOR people with Multiple long-term conditions (multimorbidity)-NIHR202020).

Home-based cardiac rehabilitation and physical activity in people with heart failure: a secondary analysis of the REACH-HF randomised controlled trials.

OBJECTIVES: To quantify the impact of a home-based cardiac rehabilitation intervention (Rehabilitation Enablement in Chronic Heart Failure (REACH-HF)) on objectively assessed physical activity (PA) of patients with heart failure (HF) and explore the extent by which patient characteristics are associated with a change in PA. DESIGN: Secondary analysis of randomised controlled trial data. SETTING: Five centres in the UK. PARTICIPANTS: 247 patients with HF (mean age 70.9±10.3 years; 28% women). INTERVENTIONS: REACH-HF versus usual care (control). PRIMARY AND SECONDARY OUTCOME MEASURES: PA was assessed over 7 days via GENEActiv triaxial accelerometer at baseline (pre-randomisation), post-intervention (4 months) and final follow-up (6-12 months). Using HF-specific intensity thresholds, intervention effects (REACH-HF vs control) on average min/day PA (inactivity, light PA and moderate-to-vigorous PA (MVPA)) over all days, week days and weekend days were examined using linear regression analysis. Multivariable regression was used to explore associations between baseline patient characteristics and change in PA. RESULTS: Although there was no difference between REACH-HF and control groups in 7-day PA levels post-intervention or at final follow-up, there was evidence of an increase in weekday MVPA (10.9 min/day, 95% CI: -2.94 to 24.69), light PA (26.9 min/day, 95% CI: -0.05 to 53.8) and decreased inactivity (-38.31 min/day, 95% CI: -72.1 to -4.5) in favour of REACH-HF. Baseline factors associated with an increase in PA from baseline to final follow-up were reduced MVPA, increased incremental shuttle walk test distance, increased Hospital Anxiety and Depression Scale anxiety score and living with a child >18 years (p<0.05). CONCLUSIONS: While participation in the REACH-HF home-based cardiac rehabilitation intervention did not increase overall weekly activity, patient's behaviour patterns appeared to change with increased weekday PA levels and reduced inactivity. Baseline PA levels were highly predictive of PA change. Future focus should be on robust behavioural changes, improving overall levels of objectively assessed PA of people with HF. TRIAL REGISTRATION NUMBERS: ISRCTN78539530 and ISRCTN86234930.

Exercise Training in Pulmonary Hypertension: AN UPDATED SYSTEMATIC REVIEW WITH META-ANALYSIS.

PURPOSE: Given that previous reviews on exercise training in pulmonary hypertension (PH) were largely based on a small number of randomized controlled trials (RCT), their conclusions are subject to bias. This review sought to identify the impact of exercise training on functional capacity and health-related quality of life (HRQoL) in PH using advanced statistical approaches such as meta-analysis by stratification according to study design. REVIEW METHODS: Five databases were searched from January 2015 to April 2020 to update a previous review. Included articles had data extracted, risk of bias (ROB) assessed, and quality rating performed. Data were analyzed using meta-analysis with a random-effects model for 6-min walk test (6MWT) distance and HRQoL. Heterogeneity was explored using stratified meta-analysis, within patient correlation and meta-regression. RESULTS: A total of 28 studies (11 RCT, 12 pre-/post-studies, 2 two-group non-RCT, and three case series) consisting of 1264 patients were included. Meta-analysis of six RCT demonstrated an improved 6MWT distance by 49.5 m (95% CI, 27.2-71.8: I2 = 73%; 254 participants; low-moderate ROB) with a low correlation coefficient of 0.34, while the 12 pre-/post-non-RCT showed an improvement of 68.69 m (95% CI, 50.50-86.69: I2 = 36%; 784 participants; high ROB) along with improvements in V˙ o2peak (weighted mean difference [WMD] = 3.03 mL/kg/min, 95% CI, 2.17-3.90: I2 = 0%, P = .82), and HRQoL (WMD = 2.74: 95% CI, -0.82 to 6.30). Metaregression showed that the benefit of exercise on 6MWT distance did not significantly vary across the trial study characteristics. CONCLUSION: This updated review identified an additional body of evidence supporting the efficacy of exercise training on 6MWT distance and HRQoL in stable PH patients. These benefits appeared to be consistent across models of delivery.

Identifying the Optimal Exercise Prescription for Patients with Coronary Artery Disease Undergoing Cardiac Rehabilitation: Protocol for a Systematic Review and Network Meta-Analysis of Randomized Control Trials.

Coronary artery disease (CAD) is one of the leading causes of mortality and morbidity. Exercise-based cardiac rehabilitation (EBCR) has been shown to improve clinical outcomes in these patients, and yet clinicians are often challenged to prescribe the most effective type of exercise training. Therefore, this systematic review and network meta-analysis (NMA) aims to formally quantify the optimal dose of exercise training interventions to improve exercise capacity and quality of life by undertaking direct and indirect pooled comparisons of randomized controlled trials. A detailed search will be conducted on PubMed/MEDLINE, Cumulative Index to Nursing and Allied Health (CINAHL), EMBASE and Web of Science. Two reviewers will screen the existing literature and assess the quality of the studies. Disagreements will be resolved through consensus. We anticipate that the analysis will include pairwise and Bayesian network meta-analyses. Most of the trials have studied the impact of exercise training comparing one or two modalities. As a result, little evidence exists to support which interventions will be most effective. The current NMA will address this gap in the literature and assist clinicians and cardiac rehabilitation specialists in making an informed decision. Results will be disseminated through peer-reviewed journals. Ethical approval is not applicable, as no research participants will be involved. PROSPERO Registration number: CRD42022262644.

Physical activity assessment by accelerometry in people with heart failure.

BACKGROUND: International guidelines for physical activity recommend at least 150 min per week of moderate-to-vigorous physical activity (MVPA) for adults, including those with cardiac disease. There is yet to be consensus on the most appropriate way to categorise raw accelerometer data into behaviourally relevant metrics such as intensity, especially in chronic disease populations. Therefore the aim of this study was to estimate acceleration values corresponding to inactivity and MVPA during daily living activities of patients with heart failure (HF), via calibration with oxygen consumption (VO2) and to compare these values to previously published, commonly applied PA intensity thresholds which are based on healthy adults. METHODS: Twenty-two adults with HF (mean age 71 ± 14 years) undertook a range of daily living activities (including laying down, sitting, standing and walking) whilst measuring PA via wrist- and hip-worn accelerometers and VO2 via indirect calorimetry. Raw accelerometer output was used to compute PA in units of milligravity (mg). Energy expenditure across each of the activities was converted into measured METs (VO2/resting metabolic rate) and standard METs (VO2/3.5 ml/kg/min). PA energy costs were also compared with predicted METs in the compendium of physical activities. Location specific activity intensity thresholds were established via multilevel mixed effects linear regression and receiver operator characteristic curve analysis. A leave-one-out method was used to cross-validate the thresholds. RESULTS: Accelerometer values corresponding with intensity thresholds for inactivity (< 1.5METs) and MVPA (≥3.0METs) were > 50% lower than previously published intensity thresholds for both wrists and waist accelerometers (inactivity: 16.7 to 18.6 mg versus 45.8 mg; MVPA: 43.1 to 49.0 mg versus 93.2 to 100 mg). Measured METs were higher than both standard METs (34-35%) and predicted METs (45-105%) across all standing and walking activities. CONCLUSION: HF specific accelerometer intensity thresholds for inactivity and MVPA are lower than previously published thresholds based on healthy adults, due to lower resting metabolic rate and greater energy expenditure during daily living activities for HF patients. TRIAL REGISTRATION: Clinical trials.gov NCT03659877, retrospectively registered on September 6th 2018.

Cardiac rehabilitation and physical activity: systematic review and meta-analysis.

OBJECTIVE: To undertake a systematic review and meta-analysis to assess the impact of cardiac rehabilitation (CR) on physical activity (PA) levels of patients with heart disease and the methodological quality of these studies. METHODS: Databases (MEDLINE, EMBASE, CENTRAL, CINAHL, PsychINFO and SportDiscus) were searched without language restriction from inception to January 2017 for randomised controlled trials (RCTs) comparing CR to usual care control in adults with heart failure (HF) or coronary heart disease (CHD) and measuring PA subjectively or objectively. The direction of PA difference between CR and control was summarised using vote counting (ie, counting the positive, negative and non-significant results) and meta-analysis. RESULTS: Forty RCTs, (6480 patients: 5825 CHD, 655 HF) were included with 26% (38/145) PA results showing a statistically significant improvement in PA levels with CR compared with control. This pattern of results appeared consistent regardless of type of CR intervention (comprehensive vs exercise-only) or PA measurement (objective vs subjective). Meta-analysis showed PA increases in the metrics of steps/day (1423, 95% CI 757.07 to 2089.43, p<0.0001) and proportion of patients categorised as physically active (relative risk 1.55, 95% CI 1.19 to 2.02, p=0.001). The included trials were at high risk of bias, and the quality of the PA assessment and reporting was relatively poor. CONCLUSION: Overall, there is moderate evidence of an increase in PA with CR participation compared with control. High-quality trials are required, with robust PA measurement and data analysis methods, to assess if CR definitely leads to important improvements in PA.