ABSTRACT
PURPOSE: Cardiorespiratory fitness (CRF) is regarded a clinical vital sign, and accurate reference values for all age groups are essential. Little data exist on CRF and cardiorespiratory function in older adults. The aim of this study was to provide normative values for CRF and cardiorespiratory function in older adults, including people with history of cardiovascular diseases (CVD). METHODS: In total, 1537 (769 women) participants age 70 to 77 yr underwent clinical examinations and cardiopulmonary exercise tests. Peak oxygen uptake (VËO2peak), ventilation (VËEpeak), expiration of carbon dioxide (VVËCO2peak), breathing frequency (BFpeak), tidal volume (VTpeak), oxygen pulse (O2 pulsepeak), ventilatory efficiency (EqVËO2peak and EqVËCO2peak), and 1-min HR recovery were assessed. RESULTS: Men compared with women had higher VËO2peak (31.3 ± 6.7 vs 26.2 ± 5.0 mL·min·kg), BFpeak (41.8 ± 8.0 vs 39.7 ± 7.1 breaths per minute), VTpeak (2.3 ± 0.5 vs 1.6 ± 0.3), O2 pulsepeak (16.4 ± 3.2 vs 11.3 ± 2.0), VËCO2peak (2.9 ± 0.2 and 1.9 ± 0.1 L·min), VËEpeak (96.2 ± 21.7 vs 61.1 ± 21.6 L·min), EqVËO2peak (38.0 ± 6.9 vs 35.1 ± 5.6), and EqVËCO2peak (33.5 ± 5.7 vs 31.9 ± 4.5). Women and men with CVD had lower VËO2peak (14% and 19%), peak HR (5% and 6%), VËEpeak (8% and 10%), VTpeak (7% and 4%), and lower EqVËCO2peak (4% and 6%) compared with their healthy counterparts, respectively. Compared with healthy women and men, 1-min HR recovery was 12% and 16% lower for women and men with CVD. CONCLUSIONS: This study represents the largest reference material on directly measured CRF and cardiorespiratory function in older men and women, with and without CVD. This novel information will help researchers and clinicians to interpret data form cardiopulmonary testing in older adults.
Subject(s)
Aged/physiology , Cardiorespiratory Fitness , Anaerobic Threshold/physiology , Anthropometry , Exercise Test , Female , Heart Rate/physiology , Humans , Male , Oxygen Consumption/physiology , Perception/physiology , Physical Exertion/physiology , Reference Values , Respiratory Function TestsABSTRACT
OBJECTIVES: Serotonin (5-HT) most likely plays an important role in the pathogenesis of pulmonary arterial hypertension (PAH). We aimed to test if venous plasma 5-HT is a potential biomarker of PAH. We also measured venous blood ß-thromboglobulin (ß-TG) in all participants to ensure that any increase in serotonin levels measured is due to platelet release. DESIGN: Blood samples from patients (n = 9) with pulmonary arterial hypertension (Group 1 of the World Health Organization classification of pulmonary hypertension) as well as healthy volunteers (n = 9) were analyzed. We used enzyme-linked immunosorbent assay (ELISA) to measure venous platelet-poor plasma 5-HT and ß-TG in patients with pulmonary arterial hypertension (PAH) and in age-matched normal controls. RESULTS: Venous platelet-free plasma 5-HT and ß-TG were almost similar in patients with PAH and healthy controls with only a slight trend toward increased 5-HT levels in patients with PAH. No correlation was found between venous platelet-poor plasma 5-HT and disease severity. There was no association between venous plasma 5-HT and the mean pulmonary artery pressure. CONCLUSIONS: Our data suggest that 5-HT is not significantly elevated in venous platelet-free plasma in patients with PAH and may accordingly not be a useful biomarker in this condition.
