Associations of cardiovascular and all-cause mortality events with oxygen uptake at ventilatory threshold

Abstract

General rightsThis document is made available in accordance with publisher policies. Please cite only the published version using the reference above. Full terms of use are available: http://www.bristol.ac.uk/pure/about/ebr-terms Abbreviations BMI = body mass index CHD = coronary heart disease CRF = cardiorespiratory fitness CVD = cardiovascular disease HDL-C = high-density lipoprotein cholesterol HR = hazard ratio IDI = integrated-discrimination-improvement KIHD = Kuopio Ischaemic Heart Disease NRI = net reclassification improvement SCD = sudden cardiac death SD = standard deviation SBP = systolic blood pressure VT = ventilatory threshold VO2 = oxygen uptake ABSTRACTBackground: Oxygen uptake (VO2) at ventilatory threshold (VT), is a cardiopulmonary exercise testing parameter which may be a proxy for peak VO2. We aimed to assess the associations of VO2 at VT with sudden cardiac death (SCD), fatal coronary heart disease (CHD) and cardiovascular disease (CVD), and all-cause mortality.Methods and Results: VO2 at VT was assessed during a submaximal exercise test using respiratory gas analyzers in the Kuopio Ischemic Heart Disease cohort of 1,639 middle-aged men. Hazard ratios (HRs) (95% CIs) were assessed. During a median follow-up of 25.6 years, 121 SCDs, 202 fatal CHDs, 312 fatal CVDs, and 703 all-cause mortality events occurred. VO2 at VT was correlated with peak VO2 (r = 0.90) and linearly associated with each outcome. Comparing extreme quartiles of VO2 at VT, the HRs (95% CIs) for SCD, fatal CHD, fatal CVD, and all-cause mortality on adjustment for established risk factors Conclusions: There are linear and inverse associations of VO2 at VT with fatal cardiovascular and allcause mortality events, which are dependent on peak VO2. Inclusion of VO2 at VT in the standard established risk factors panel significantly improves the prediction and classification of long-term CVD mortality risk.

Joint associations of sauna bathing and cardiorespiratory fitness on cardiovascular and all-cause mortality risk: a long-term prospective cohort study

“…Cardiorespiratory fitness was categorised into low and high CRF based on median cut-offs of CRF, whiles FSB was categorized into low and high frequencies (defined as ≤ 2 and 3-7 sauna sessions per week respectively). These categories were created based on the distribution of the data and findings from our previous studies conducted on the topic (11,13). For the associations of one exposure (e.g.…”

“…Study participants were part of the Kuopio Ischemic Heart Disease (KIHD) risk factor study, which is an ongoing representative population-based study comprising a representative sample of middle-aged men aged 42-61 years recruited from eastern Finland. Details of recruitment methods and assessment of risk markers have been described in previous reports (13,14). Briefly, baseline examinations were conducted between March 1984 and December 1989.…”

“…Resting blood pressure was measured between 8 and 10 a.m. with a random-zero sphygmomanometer. Maximal oxygen uptake was used as a measure of CRF, which was assessed using respiratory gas exchange analyzers (Medical Graphics, MCG, St. Paul, Minnesota) during cycle ergometer exercise testing as described in detail elsewhere (13). Briefly, a maximal symptom-limited exercise tolerance test was performed between 08:00 and 10:00 hours using an electrically braked cycle ergometer.…”

Association of oxygen uptake at ventilatory threshold with risk of incident hypertension: a long-term prospective cohort study

“…7 VO2 at VT is considered as a measure of cardiovascular fitness and a reliable index of aerobic capacity, 1 and has been suggested to be protective of fatal cardiovascular outcomes as well as all-cause mortality. 8 Previous findings have suggested VO2 at VT to be a suitable proxy for peak VO2. 8 Though peak VO2 is a gold standard measure of aerobic capacity, some individuals are unable to achieve this VO2 level due to exercise-related limitations such as musculoskeletal problems.…”

“…8 Previous findings have suggested VO2 at VT to be a suitable proxy for peak VO2. 8 Though peak VO2 is a gold standard measure of aerobic capacity, some individuals are unable to achieve this VO2 level due to exercise-related limitations such as musculoskeletal problems. In such instances, VO2 at VT, which can be assessed safely at submaximal exercise levels, may be used as a suitable replacement for the assessment of maximal VO2.…”