Evaluation of dyspnea of unknown etiology in HIV patients with cardiopulmonary exercise testing and cardiovascular magnetic resonance imaging.

AIM: Human Immunodeficiency Virus (HIV) patients commonly experience dyspnea for which an immediate cause may not be always apparent. In this prospective cohort study of HIV patients with exercise limitation, we use cardiopulmonary exercise testing (CPET) coupled with exercise cardiovascular magnetic resonance (CMR) to elucidate etiologies of dyspnea. METHODS AND RESULTS: Thirty-four HIV patients on antiretroviral therapy with dyspnea and exercise limitation (49.7 years, 65% male, mean absolute CD4 count 700) underwent comprehensive evaluation with combined rest and maximal exercise treadmill CMR and CPET. The overall mean oxygen consumption (VO2) peak was reduced at 23.2 ± 6.9 ml/kg/min with 20 patients (58.8% of overall cohort) achieving a respiratory exchange ratio > 1. The ventilatory efficiency (VE)/VCO2 slope was elevated at 36 ± 7.92, while ventilatory reserve (VE: maximal voluntary ventilation (MVV)) was within normal limits. The mean absolute right ventricular (RV) and left ventricular (LV) contractile reserves were preserved at 9.0% ± 11.2 and 9.4% ± 9.4, respectively. The average resting and post-exercise mean average pulmonary artery velocities were 12.2 ± 3.9 cm/s and 18.9 ± 8.3 respectively, which suggested lack of exercise induced pulmonary artery hypertension (PAH). LV but not RV delayed enhancement were identified in five patients. Correlation analysis found no relationship between peak VO2 measures of contractile RV or LV reserve, but LV and RV stroke volume correlated with PET CO2 (p = 0.02, p = 0.03). CONCLUSION: Well treated patients with HIV appear to have conserved RV and LV function, contractile reserve and no evidence of exercise induced PAH. However, we found evidence of impaired ventilation suggesting a non-cardiopulmonary etiology for dyspnea.

Effect of Intentional Weight Loss on Mortality Biomarkers in Older Adults With Obesity.

BACKGROUND: Observational research has identified several mortality biomarkers; however, their responsiveness to change is unknown. We tested whether the Healthy Aging Index (HAI) and other mortality biomarkers were responsive to intentional weight loss (WL), which is associated with lower mortality risk in recent meta-analyses. METHODS: Older adults (70.3 ± 3.7 years) with obesity were randomized into a 6-month WL (n = 47) or weight stability (WS: ±5% baseline weight; n = 48) program. Baseline and 6-month HAI score (0-10) was calculated from component sum (each 0-2: systolic blood pressure, forced vital capacity [FVC], creatinine, fasting blood glucose [FBG], Montreal Cognitive Assessment), and gait speed, grip strength, Digit Symbol Substitution Test, FEV1, Interleukin-6, C-Reactive Protein, and Cystatin-C were assessed at baseline and 6 months. RESULTS: Mean baseline HAI was 3.2 ± 1.6. By 6 months, WL participants lost 8.87 (95% CI: -10.40, -7.34) kg, whereas WS participants remained weight stable. WL group reduced HAI score (WL: -0.75 [95% CI: -1.11, -0.39] vs WS: -0.22 [95% CI: -0.60, 0.15]; p = .04), and components changing the most were FBG (WL: -3.89 [95% CI: -7.78, 0.00] mg/dL vs WS: 1.45 [95% CI: -2.61, 5.50] mg/dL; p = .047) and FVC (WL: 0.11 [95% CI: -0.01, 0.23] L vs WS: -0.05 [95% CI: -0.17, 0.08] L; p = .06). Among other biomarkers, only Cystatin-C significantly changed (WL: -2.53 [95% CI: -4.38, -0.68] ng/mL vs WS: 0.07 [95% CI: -1.85, 1.98] ng/mL; p = .04). Combining treatment groups, 1 kg WL was associated with a 0.07 (95% CI: 0.03, 0.12) HAI reduction (p < .01). CONCLUSION: Intentional WL via caloric restriction reduced HAI score by 0.53 points, largely attributable to metabolic and pulmonary improvements.

No Performance or Affective Advantage of Drinking versus Rinsing with Water during a 15-km Running Session in Female Runners.

The advantage of ingesting fluids during endurance exercise lasting < 90 min has recently been challenged, but literature confirming or disputing this case is limited, particularly for female athletes. This study examined the effects of consuming water versus mouth rinsing with water during a running time trial. Recreationally active female runners (n = 19) completed two, 15-km time trials on an outdoor course in temperate environment (~20ºC; 87% RH) separated by at least one week in a randomized cross-over study design. Participants consumed 355 ml of water (DW) during their run or mouth rinsed (MR) with water from a handheld water bottle every 3 km for 5 s with physiological, perceptual, and affective variables assessed. DW or MR did not affect completion time (79.8 ± 8.1 min and 79.2 ± 8.2 min, p = 0.23), HR (p = 0.35), or RPE (p = 0.73), respectively. Sweat losses were greater (p = 0.03) for DW: 1.47 ± 0.34 L compared to MR: 1.28 ± 0.27 L; however, thirst sensation was not significantly different for MR: 6.7 ± 1.4 compared to DW: 6.2 ± 1.6. A significant effect was exhibited for time (p < 0.01) but not condition for Feeling Scale and Felt Arousal Scale or Energetic and Tense Arousal. Carrying only one smaller fluid container for MR versus a larger or multiple water bottles/backpack systems used for water consumption can reduce fluid load carried during extended duration runs without altering performance or affect for runs of 1.0-1.5 h. MR may also be beneficial to decrease thirst without ingesting fluid for runners that limit exercise fluid consumption because of gastrointestinal discomfort concerns.