Cardiorespiratory Fitness, Inflammation, and Risk of Chronic Obstructive Pulmonary Disease in Middle-Aged Men: A COHORT STUDY

Unraveling the link between cardiorespiratory fitness and cancer: a state-of-the-art review

Cardiorespiratory fitness (CRF) not only reflects an individual's capacity to perform physical activities but also encapsulates broader effects on the basic biology of aging. This review aims to summarize the evidence on the influence of CRF on overall and site-specific cancer risks. It delves into the biological mechanisms through which CRF may exert its effects, explores the clinical implications of these findings, identifies gaps in the current evidence base, and suggests directions for future research. The synthesis of findings reveals that higher CRF levels (general threshold of > 7 METs) are consistently associated with a reduced risk of a range of cancers, including head and neck, lung, breast, gastrointestinal, particularly pancreatic and colorectal, bladder, overall cancer incidence and mortality, and potentially stomach and liver, bile duct, and gall bladder cancers. These inverse associations between CRF and cancer risk do not generally differ across age groups, sex, race, or adiposity, suggesting a universal protective effect of CRF. Nonetheless, evidence linking CRF with skin, mouth and pharynx, kidney, and endometrial cancers is limited and inconclusive. Conversely, higher CRF levels may be potentially linked to an increased risk of prostate cancer and hematological malignancies, such as leukemia and myeloma, although the evidence is still not conclusive. CRF appears to play a significant role in reducing the risk of several cancers through various biological mechanisms, including inflammation reduction, immune system enhancement, hormonal regulation, and metabolic improvements. Overall, enhancing CRF through regular physical activity offers a vital, accessible strategy for reducing cancer risk and extending the health span. Future research should aim to fill the existing evidence gaps regarding specific cancers and elucidate the detailed dose-response relationships between CRF levels and cancer risk. Studies are also needed to elucidate the causal relationships and mechanistic pathways linking CRF to cancer outcomes.

Cardiorespiratory fitness, atrial fibrillation and stroke: a review of the evidence in 2024

INTRODUCTION

The body of evidence linking cardiorespiratory fitness (CRF) levels with the risk of atrial fibrillation (AF) and stroke - two interconnected cardiovascular conditions - is not entirely consistent. Furthermore, specific CRF thresholds beyond which the risk of AF or stroke might not decrease are not well defined.

AREAS COVERED

This review summarizes research evidence on the role of CRF in the development of AF and stroke including dose-response relationships in general population participants, explores the biological mechanisms through which CRF may exert its effects, assesses the potential implications for clinical care and population health, identifies gaps in the current evidence, and suggest directions for future research. MEDLINE and Embase were searched from inception until July 2024 to identify observational longitudinal and interventional studies as well as systematic reviews and meta-analyses related to these study designs.

EXPERT OPINION

In the general population, increasing levels of CRF, achieved through consistent physical activity, can significantly reduce the likelihood of developing AF and stroke. The findings also advocate for a tailored approach to exercise prescriptions, acknowledging the plateau in benefits for AF risk beyond certain CRF levels, while advocating for higher intensity or prolonged activity to further reduce stroke risk.

Self-reported walking pace and 10-year cause-specific mortality: A UK biobank investigation

OBJECTIVE

To investigate associations of self-reported walking pace (SRWP) with relative and absolute risks of cause-specific mortality.

PATIENTS AND METHODS

In 391,652 UK Biobank participants recruited in 2006-2010, we estimated sex- and cause-specific (cardiovascular disease [CVD], cancer, other causes) mortality hazard ratios (HRs) and 10-year mortality risks across categories of SRWP (slow, average, brisk), accounting for confounders and competing risk. Censoring occurred in September 30, 2021 (England, Wales) and October 31, 2021 (Scotland).

RESULTS

Over a median follow-up of 12.6 years, 22,413 deaths occurred. In women, the HRs comparing brisk to slow SRWP were 0.74 (95% CI: 0.67, 0.82), 0.40 (0.33, 0.49), and 0.29 (0.26, 0.32) for cancer, CVD, and other causes of death, respectively, and 0.71 (0.64, 0.78), 0.38 (0.33, 0.44), and 0.29 (0.26, 0.32) in men. Compared to CVD, HRs were greater for other causes (women: 39.6% [6.2, 72.9]; men: 31.6% [9.8, 53.5]) and smaller for cancer (-45.8% [-58.3, -33.2] and - 45.9% [-54.8, -36.9], respectively). For all causes in both sexes, the 10-year mortality risk was higher in slow walkers, but varied across sex, age, and cause, resulting in different risk reductions comparing brisk to slow: the largest were for other causes of death at age 75 years [women: -6.8% (-7.7, -5.8); men: -9.5% (-10.6, -8.4)].

CONCLUSION

Compared to slow walkers, brisk SRWP was associated with reduced cancer (smallest reduction), CVD, and other (largest) causes of death and may therefore be a useful clinical predictive marker. As absolute risk reductions varied across age, cause, and SRWP, certain groups may particularly benefit from interventions to increase SRWP.

Cardiorespiratory Fitness and Risk of Aortic Stenosis (from a Prospective Cohort Analysis)

Cardiorespiratory fitness (CRF) is a major risk factor and predictor of atherosclerotic cardiovascular disease. However, the relationship between CRF and risk of aortic stenosis (AS) has not been previously investigated. Thus, we aimed to assess the prospective association between CRF and risk of AS. CRF, as measured by maximal oxygen uptake, was assessed using a respiratory gas exchange analyzer during cardiopulmonary exercise testing in 2,308 men aged 42 to 61 years recruited into the Kuopio Ischemic Heart Disease prospective cohort study. Hazard ratios (HRs) with 95% confidence intervals (CIs) were estimated for AS. During a median follow-up of 27 years, 101 cases of AS occurred. Dose-response analysis suggested there might be a nonlinear relation between CRF levels and AS risk. In an analysis adjusted for age, body mass index, systolic blood pressure, total cholesterol, high-density lipoprotein cholesterol, smoking, history of type 2 diabetes mellitus, and coronary heart disease, the HRs 95% (CIs) of AS were 0.57 (0.34 to 0.96) and 0.91 (0.53 to 1.57) for participants in the middle and upper third of CRF levels, respectively, compared with participants in the bottom third. After further adjustment for alcohol consumption, the corresponding HRs (95% CIs) were 0.58 (0.34 to 0.97) and 0.91 (0.53 to 1.56), respectively. In conclusion, higher CRF levels may be associated with a lower incidence of AS in middle-aged and older Finnish men. Given the likely limitations of low statistical power, further research is needed to provide insights into the dose-response nature of any relationship between CRF and AS.

Physical Activity and Cardiorespiratory Fitness as Modulators of Health Outcomes: A Compelling Research-Based Case Presented to the Medical Community

The beneficial health effects and prognostic significance of regular moderate-to-vigorous physical activity (PA), increased cardiorespiratory fitness (CRF), or both are often underappreciated by the medical community and the patients they serve. Individuals with low CRF have higher annual health care costs, higher rates of surgical complications, and are two to three times more likely to die prematurely than their fitter counterparts when matched for risk factor profile or coronary calcium score. Increased levels of habitual PA before hospitalization for acute coronary syndromes are also associated with better short-term cardiovascular outcomes. Accordingly, this review examines these relations and the potential underlying mechanisms of benefit (eg, exercise preconditioning), with specific reference to the incidence of cardiovascular, cancer, and coronavirus diseases, and the prescriptive implications and exercise thresholds for optimizing health outcomes. To assess the evidence supporting or refuting the benefits of PA and CRF, we performed a literature search (PubMed) and critically reviewed the evidence to date. In aggregate, these data are presented in the context of clarifying the impact that regular PA and/or increased CRF have on preventing and treating chronic and infectious diseases, with reference to evidence-based exercise thresholds that the medical community can embrace and promote.

Cardiorespiratory Fitness, Inflammation, and Risk of Sudden Cardiac Death in Middle-Aged Men

Inflammation and cardiorespiratory fitness (CRF) are each independently related to the risk of sudden cardiac death (SCD). The interplay between CRF, inflammation and SCD is not well understood. We aimed to study the separate and joint associations of inflammation (high-sensitivity C-reactive protein [hsCRP]) and CRF with SCD risk in a cohort of Caucasian men. In 1,749 men aged 42 to 61 years without a history of coronary heart disease at baseline, serum hsCRP was measured using an immunometric assay, and CRF was assessed using a respiratory gas exchange analyzer during exercise testing. hsCRP was categorized as normal and high (≤3 and >3 mg/L, respectively) and CRF as low and high (median cutoff). A total of 148 SCD events occurred during a median follow-up of 28.9 years. Comparing high versus normal hsCRP, the multivariable-adjusted hazard ratio (95% confidence interval) for SCD was 1.65 (1.11 to 2.45), which remained similar on further adjustment for CRF 1.62 (1.09 to 2.40). Comparing high versus low CRF, the multivariable-adjusted hazard ratio for SCD was 0.61 (0.42 to 0.89), which remained persistent after adjustment for hsCRP 0.64 (0.44 to 0.93). Compared with normal hsCRP-low CRF, normal hsCRP-high CRF was associated with a decreased SCD risk of 0.65 (0.43 to 0.99), high hsCRP-low CRF was associated with an increased SCD risk of 1.72 (1.10 to 2.69), with no evidence of a relationship between high hsCRP-high CRF and SCD risk 0.86 (0.39 to 1.88). Positive additive and multiplicative interactions were found between hsCRP and CRF. In a middle-aged Finnish male population, both hsCRP and CRF are independently associated with SCD risk. However, high CRF levels appear to offset the increased SCD risk related to high hsCRP levels.