Hypocapnia is a biological marker for orthostatic intolerance in some patients with chronic fatigue syndrome

CONTEXT: Patients with chronic fatigue syndrome and those with orthostatic intolerance share many symptoms, yet questions exist as to whether CFS patients have physiological evidence of orthostatic intolerance. OBJECTIVE: To determine if some CFS patients have increased rates of orthostatic hypotension, hypertension, tachycardia, or hypocapnia relative to age-matched controls. DESIGN: Assess blood pressure, heart rate, respiratory rate, end tidal CO2 and visual analog scales for orthostatic symptoms when supine and when standing for 8 minutes without moving legs. SETTING: Referral practice and research center. PARTICIPANTS: 60 women and 15 men with CFS and 36 women and 4 men serving as age matched controls with analyses confined to 62 patients and 35 controls showing either normal orthostatic testing or a physiological abnormal test. MAIN OUTCOME MEASURES: Orthostatic tachycardia; orthostatic hypotension; orthostatic hypertension; orthostatic hypocapnia or combinations thereof. RESULTS: CFS patients had higher rates of abnormal tests than controls (53% vs 20%, p < .002), but rates of orthostatic tachycardia, orthostatic hypotension, and orthostatic hypertension did not differ significantly between patients and controls (11.3% vs 5.7%, 6.5% vs 2.9%, 19.4% vs 11.4%, respectively). In contrast, rates of orthostatic hypocapnia were significantly higher in CFS than in controls (20.6% vs 2.9%, p < .02). This CFS group reported significantly more feelings of illness and shortness of breath than either controls or CFS patients with normal physiological tests. CONCLUSION: A substantial number of CFS patients have orthostatic intolerance in the form of orthostatic hypocapnia. This allows subgrouping of patients with CFS and thus reduces patient pool heterogeneity engendered by use of a clinical case definition

Changes in physical health among participants in a multidisciplinary health programme for long-term unemployed persons

Background. The relationship between poor health and unemployment is well established. Health promotion among unemployed persons may improve their health. The aims of this study were to investigate characteristics of non-participants and drop-outs in a multidisciplinary health promotion programme for long-term unemployed persons with health complaints, to evaluate changes in physical health among participants, and to investigate determinants of improvement in physical health. Methods. A longitudinal, non-controlled design was used. The programme consisted of two weekly exercise sessions and one weekly cognitive session during 12 weeks. The main outcome measures were body mass index, blood pressure, cardiorespiratory fitness, abd

Respiratory and immune response to maximal physical exertion following exposure to secondhand smoke in healthy adults

© 2012 The Authors. Published by PLOS. This is an open access article available under a Creative Commons licence. The published version can be accessed at the following link on the publisher’s website: https://doi.org/10.1371/journal.pone.0031880We assessed the cardiorespiratory and immune response to physical exertion following secondhand smoke (SHS) exposure through a randomized crossover experiment. Data were obtained from 16 (8 women) non-smoking adults during and following a maximal oxygen uptake cycling protocol administered at baseline and at 0-, 1-, and 3- hours following 1-hour of SHS set at bar/restaurant carbon monoxide levels. We found that SHS was associated with a 12% decrease in maximum power output, an 8.2% reduction in maximal oxygen consumption, a 6% increase in perceived exertion, and a 6.7% decrease in time to exhaustion (P<0.05). Moreover, at 0-hours almost all respiratory and immune variables measured were adversely affected (P<0.05). For instance, FEV 1 values at 0-hours dropped by 17.4%, while TNF-α increased by 90.1% (P<0.05). At 3-hours mean values of cotinine, perceived exertion and recovery systolic blood pressure in both sexes, IL4, TNF-α and IFN-γ in men, as well as FEV 1/FVC, percent predicted FEV 1, respiratory rate, and tidal volume in women remained different compared to baseline (P<0.05). It is concluded that a 1-hour of SHS at bar/restaurant levels adversely affects the cardiorespiratory and immune response to maximal physical exertion in healthy nonsmokers for at least three hours following SHS. © 2012 Flouris et al.Published versio

PHARMACOTHERAPY QUALITY IN PATIENTS WITH ARTERIAL HYPERTENSION OBSERVED IN PRIMARY CARE PRACTICE. HYPERTENSION REGISTER DATA

Aim. To assess (on the basis of Russian national guidelines on arterial hypertension (HT), 2004) quality of pharmacotherapy measures among hypertensive patients observed in primary care practice. Material and methods. Data on 12 604 patients with HT (7 819 women, 4 785 men, aged 59.5±12.0 years) from 13 regions of Russia observed in primary care units during 2007 were enrolled in the study. Compliance with recommendations on decision making about pharmacotherapy need (risk category assessment) and adequacy were evaluated. Results. 64% of patients with HT had no drug prescriptions in their outpatient card in 2007. 4 880 patients from 12 604 enrolled HT patients (38.7%) had all data necessary for risk assessment. 3920 patients (31% of the whole studied group) had pharmacotherapy indications (high or very high risk). Only 819 HT patients (6.5% of the whole number of enrolled patients) had antihypertensive pharmacotherapy completely corresponding to their clinical status. Conclusion. The quality of pharmacotherapy measures carried out in primary care practice during 2007 did not conform to HT guidelines

Induction and decay of short-term heat acclimation

“The original publication is available at www.springerlink.com”. Copyright SpringerThe purpose of this work was to investigate adaptation and decay from short-term (5-day) heat acclimation (STHA). Ten moderately trained males (mean ± SD age 28 ± 7 years; body mass 74.6 ± 4.4 kg; 4.26 ± 0.37 l min−1) underwent heat acclimation (Acc) for 90-min on 5-days consecutively (T a = 39.5°C, 60% RH), under controlled hyperthermia (rectal temperature 38.5°C). Participants completed a heat stress test (HST) 1 week before acclimation (Acc), then on the 2nd and 8th day (1 week) following Acc (T a = 35°C, 60% RH). Seven participants completed HSTs 2 and 3 weeks after Acc. HST consisted of 90-min cycling at 40% peak power output before an incremental performance test. Rectal temperature at rest (37.1 ± 0.4°C) was not lowered by Acc (95% CI −0.3 to 0.2°C), after 90-min exercise (38.6 ± 0.5°C) it reduced 0.3°C (−0.5 to −0.1°C) and remained at this level 1 week later (−0.5 to −0.1°C), but not two (0.1°C −0.4 to 0.5°C; n = 7) or 3 weeks. Similarly, heart rate after 90-min exercise (146 ± 21 b min−1) was reduced (−13: −6 to −20 b min−1) and remained at this level after 1 week (−13: −6 to −20 b min−1) but not two (−9: 6 to −23 b min−1; n = 7) or 3 weeks. Performance (746 s) increased 106 s: 59 to 152 s after Acc and remained higher after one (76 s: 31 to 122) but not two (15 s: −88 to 142 s; n = 7) or 3 weeks. Therefore, STHA (5-day) induced adaptations permitting increased heat loss and this persisted 1 week but not 2 weeks following Acc.Peer reviewe

Strain solitary waves in a thin-walled waveguide

A mathematical model is proposed to describe bulk longitudinal waves in a nonlinearly elastic thin-walled cylindrical shell. The equation of motion for the longitudinal displacement is derived. In case of the homogeneous shell, this equation is reduced to the doubly dispersive equation for the linear longitudinal strain component and provides a solitary wave solution. Results of the first experimental observation of the bulk strain soliton in a duct-like shell are presented, and both the wave amplitude and velocity are estimated