1Department of Pulmonology and Sleep Disorders Centre, University Hospital Zurich, Zurich, Switzerland; 2Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, Zurich, Switzerland; 3Centre of Competence Sleep & Health, University of Zurich, Zurich, Switzerland Purpose: Patients with chronic obstructive pulmonary disease (COPD) are particularly vulnerable to hypoxia-induced autonomic dysregulation. Hypoxemia is marked during sleep. In COPD, altitude exposure is associated with an increase in blood pressure (BP) and a decrease in baroreflex-sensitivity (BRS). Whether nocturnal oxygen therapy (NOT) may mitigate these cardiovascular autonomic changes in COPD at altitude is unknown. Materials and Methods: In a randomized placebo-controlled cross-over trial, 32 patients with moderate-to-severe COPD living <800 m were subsequently allocated to NOT and placebo during acute exposure to altitude. Measurements were done at low altitude at 490 m and during two stays at 2048 m on NOT (3 L/min) and placebo (3 L/min, ambient air) via nasal cannula. Allocation and intervention sequences were randomized. Outcomes of interest were BP, BRS (from beat-to-beat BP measurement), BP variability (BPV), and heart rate. Results: About 23/32 patients finished the trial per protocol (mean (SD) age 66 (5) y, FEV1 62 (14) % predicted) and 9/32 experienced altitude-related illnesses (8 vs 1, p < 0.05 placebo vs NOT). NOT significantly mitigated the altitude-induced increase in systolic BP compared to placebo (Δ median −5.8 [95% CI −22.2 to −1.4] mmHg, p = 0.05) but not diastolic BP (−3.5 [95% CI −12.6 to 3.0] mmHg; p = 0.21) or BPV. BRS at altitude was significantly higher in NOT than in placebo (1.7 [95% CI 0.3 to 3.4] ms/mmHg, p = 0.02). Conclusion: NOT may protect from hypoxia-induced autonomic dysregulation upon altitude exposure in COPD and thus protect from a relevant increase in BP and decrease in BRS. NOT may provide cardiovascular benefits in COPD during conditions of increased hypoxemia and may be considered in COPD travelling to altitude.
Background Mesh surgery for stress urinary incontinence or pelvic organ prolapse can result in complications such as mesh exposure, mesh extrusion, voiding dysfunction, dyspareunia, and pain. There is limited knowledge or guidance on the effective management for mesh-related complications. Objective To determine the best management of mesh complications; a systematic review was conducted as part of the national clinical guideline 'Urinary incontinence (update) and pelvic organ prolapse in women: management'. Search strategy Search strategies were developed for each indication for referral. Selection criteria Relevant interventions included complete or partial mesh removal, mesh division, and non-surgical treatments such as vaginal estrogen. Data collection and analysis Characteristics and outcome data were extracted, and as a result of the heterogeneous nature of the data a narrative synthesis was conducted. Main results Twenty-four studies were included; five provided comparative data and four studies stated the indication for referral. Reported outcomes (including pain, dyspareunia, satisfaction, quality of life, incontinence, mesh exposure, and recurrence) and the reported incidences of these varied widely. Conclusions The current evidence base is limited in quantity and quality and does not permit firm recommendations to be made on the most effective management for mesh-related complications. Robust data are needed so that mesh complications can be managed effectively in the future. Tweetable abstract Systematic review demonstrates that the outcomes following mesh revision surgery are highly variable.
Background Anterior compartment prolapse is the most common pelvic organ prolapse (POP) with a range of surgical treatment options available. Objectives To compare the clinical effectiveness and cost-effectiveness of surgical treatments for the repair of anterior POP. Methods We conducted a systematic review of randomised controlled trials comparing surgical treatments for women with POP. Network meta-analysis was possible for anterior POP, same-site recurrence outcome. A Markov model was used to compare the cost-utility of surgical treatments for the primary repair of anterior POP from a UK National Health Service perspective. Main results We identified 27 eligible trials for the network meta-analysis involving eight surgical treatments tested on 3194 women. Synthetic mesh was the most effective in preventing recurrence at the same site. There was no evidence to suggest a difference between synthetic non-absorbable mesh, synthetic partially absorbable mesh, and biological mesh. The cost-utility analysis, which incorporated effectiveness, complications and cost data, found non-mesh repair to have the highest probability of being cost-effective. The conclusions were robust to model inputs including effectiveness, costs and utility values. Conclusions Anterior colporrhaphy augmented with mesh appeared to be cost-ineffective in women requiring primary repair of anterior POP. There is a need for further research on long-term effectiveness and the safety of mesh products to establish their relative cost-effectiveness with a greater certainty. Tweetable abstract New study finds mesh cost-ineffective in women with anterior pelvic organ prolapse.
Mesh surgery for stress urinary incontinence or pelvic organ prolapse can result in complications such as mesh exposure, mesh extrusion, voiding dysfunction, dyspareunia, and pain. There is limited knowledge or guidance on the effective management for mesh‐related complications.
Pulmonary vascular diseases primary manifest with impaired exercise tolerance. We hypothesized that exercise pulmonary hemodynamics would predict outcome in arterial and inoperable chronic thromboembolic pulmonary hypertension (PAH, CTEPH).
Background: Pulmonary hypertension (PH) due to COPD has dismal prognosis. PH-target therapy may worsen ventilation-perfusion-mismatch and is insufficiently studied. We retrospectively analysed the long-term effect of PH-target therapy in COPD-PH.
Die Lebensqualität (Quality of life, QoL) im Allgemeinen und die gesundheitsbezogene Lebensqualität („Health-related QoL; HRQOL) im Besonderen rücken aktuell immer mehr in den Fokus des Interesse bei chronischen Krankheiten und somit auch für Patienten mit einer pulmonal-arteriellen Hypertonie (PAH) oder chronisch thromboembolischen pulmonalen Hypertonie (CTEPH). Es gibt Überlegungen, diese als primäre oder ko-primäre Outcome-Parameter in Studien einzusetzen. Die Erfassung der QoL/HRQOL und die Objektivierung klinisch relevanter Veränderungen dieser ist allerdings nicht trivial. Diese Übersichtsarbeit beleuchtet sowohl die allgemeinen Aspekte der Evaluation der HRQOL als auch die Vor- und Nachteile der hierbei aktuell verwendeten Instrumente.
Body weight and body mass index (BMI) were studied in non professional cyclists. BMI increased from 22.2 +/- 2.3 kg/m2 (20 to 29 y) to 23.8 +/- 1.7 kg/m2 (55 to 77 y) (mean +/- SD). The mean increase per decade was 0.5 kg/m2, markedly less than in the general Swiss population (0.8 to 1.0 kg/m2). Overweight (BMI 25.1-29.9 kg/m2) prevalence increased from 7.4% (20 to 29 y) to 25.5% (55 to 77 y) and obesity (BMI +/- 30.0 kg/m2) was rare (0.2%, n = 1). The amount of sport correlated negatively with BMI change. A high amount of moderate to heavy physical activity (five hours weekly) was required to avoid an increase in BMI. This amount is to high for the general population. Thus, control of energy intake should be advised together with physical activity.
The transplantation of osteochondral (cartilage-bone) plugs is an alternative approach to treat local, full thickness cartilage defects in young patients. It is technically difficult to control the amount of the press fit tolerance and the position of the osteochondral (OC) plug in the recipient hole. Inadequate placement of the OC plugs may produce abnormal stress and strain distributions within the cartilage, and thus influence the regeneration of the injured cartilage site and the maintenance of opposing, healthy cartilage surfaces. In the present study, the influence of press fit tolerance and the placement of the OC plug on the joint contact mechanics was simulated using finite element methods. The joint was assumed to be axi-symmetric with a spherical femur and tibia and a cylindrical OC plug. Our simulations showed that small misplacements of the OC plug induced abnormal tension in the articular cartilage of the opposing, healthy cartilage surface. Such tension might induce unpredictable adaptations, or possibly degenerations, in the opposing cartilage layer. The contact stress profiles in the joint were predicted to change discontinuously across the plug/recipient interface, even when the plug was perfectly placed in the recipient hole, i.e., the plug’s surface was aligned with the recipient surface. For a fixed coefficient of friction and a fixed fit tolerance, the maximal sliding force was predicted to vary with the size of the plug and reached a maximum at a specific plug diameter. The present simulations should be helpful for the design of instruments for osteochondral transplantation and placement of OC plugs, for understanding articular cartilage adaptation following osteochondral repair, and for providing insight into the mechanics at the transplant/recipient interface where proper integration of the plug into the joint is most problematic.
We hypothesize that the neuromuscular system is designed to function effectively in accomplishing everyday movement tasks. Since everyday movement tasks may vary substantially in terms of speed and resistance, we speculate that agonistic muscles contribute differently to varying movement tasks such that the mechanical, structural, and physiological properties of the system are optimized at all times. We further hypothesize that a mechanical perturbation to the musculoskeletal system, such as the loss of an important joint ligament or the change of a muscle's line of action, causes an adaptation of the system aimed at reestablishing effective function. Here, we demonstrate how the specificity of the cat ankle extensors is used to accommodate different locomotor tasks. We then illustrate how the loss of an important ligament in the cat knee leads to neuromuscular adaptation. Finally, we discuss the adaptability of skeletal muscle following an intervention that changes a muscle's line of action, moment arm, and excursion.
Elevated plasma homocysteine levels may lead to an increased risk for atherosclerosis. Besides genetic factors a deficiency of folate, vitamin B6 and/or vitamin B12 may lead to an increase in the plasma concentration of this sulfur containing amino acid. Homocysteine may enhance by several direct and/or indirect mechanisms the pathogenesis of atherosclerosis. In this review selected aspects of homocysteine in relation to clinical practice will be discussed.
Objective: Different factors such as exercise habits and alcohol consumption may modulate postprandial lipid metabolism. What are the effects of alcohol on postprandial metabolism in untrained and trained individuals?Methods: The postprandial lipid response to an oral fat load (1 g fat per kg body weight (bw)) with and without alcohol (0.5 g/kg bw) was evaluated in physically trained healthy young men (T, n = 12, mean +/- SD age 27 +/- 3 years, BMI 21.6 +/- 1.4 kg/m(2)) after a premeal running session and in untrained healthy young men (UT, n = 8, age 24 +/- 1 years, BMI 23.2 +/- 1.8 kg/m(2)) without a premeal exercise session. The T subjects ingested 35.5 +/- 2.7 g alcohol, the UT subjects 38 +/- 0.6 g. Fat was given as butter and the carbohydrates as marmalade and zwieback (rusk). The T subjects received 1.20 +/- 0.05 g fat and 1.02 +/- 0.04 g carbohydrates per kilogram lean body mass. The corresponding numbers for the UT subjects were 1.28 +/- 0.08 g and 1.20 +/- 0.06 g, The postprandial lipemia was observed fur an eight-hour period.Results: Alcohol led to an increase to the triacylglycerol area under the curve (AUC) in the T subjects from 7.4 =/- 0.4 mmol/L * h on the control day to 11.3 +/- 0.9 mmol/L * h (p = 0.001), The corresponding numbers in the UT subjects were 13.4 +/- 2.3 mmol/L * h to 19.4 +/- 3.5 mmol/L * h (p = 0.004). Alcohol intake and physical activity training were the major determinants of the triacylglycerol (TG) AUC in these subjects.Conclusion: The ingestion of a high fat meal in combination with alcohol leads to an increased in the postprandial lipemia independently from the level of training. It is suggested that this unfavorable effect of alcohol and a high Fat diet could be modified by fat restriction or a combination of a premeal exercise session and a higher level of physical activity training.
Several recent studies reported a prevalence rate of overweight (25 < BMI < 30 kg/m2) of 4-30% as a function of age and gender. It is well known that the fat distribution pattern represents a major modifier of health risks associated with obesity. For clinical purposes the measurement of the waist to hip ratio represents one of the most valid tools for the assessment of the fat distribution pattern. During the air show AIR94 in Buochs (Nidwalden, Switzerland) 1568 visitors participated voluntarily in a study where several cardiovascular risk factors and behaviours were assessed with the help of a questionnaire, besides others the W/H ratio was measured. This study represents the first epidemiological study of the fat distribution pattern in a large population group in Switzerland. The mean (+/- SD) age of the whole population was 50.3 +/- 16.2 years, the mean body mass index (BMI) 25.5 +/- 3.7 kg/m2, the mean W/H ratio 0.89 +/- 0.09. The BMI and the W/H ratio for the different age decades was calculated. In women the normal value of 0.8 for the W/H ratio is bypassed in the 4th decade of age; the normal value of 0.95 for men is surpassed in the 6th decade of life. These findings are of great public health importance since they illustrate nicely the importance to control body weight and the fat distribution pattern early in life. The major modifiable risk factors for the abdominal accumulation of fat are the excess of calories (especially in form of fat), physical inactivity, smoking and alcohol consumption, stress and probably weight cycling. The control of these risk factors is strongly needed.