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Weight loss in chronic obstructive airways disease (COPD) is associated with an increased energy cost of breathing. To determine an association between body composition and the inflammatory response we studied 80 clinically stable patients. Body composition was determined anthropometrically and skeletal muscle mass was determined as the creatinine-height index (CHI). Forty patients had their nitrogen balance determined. Circulating concentrations of interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-alpha), and their soluble receptors were determined for 68 patients. Body mass index (BMI) was normal (> 20 kg/m(2)) in 55 patients, of whom 17 (31%) had a low CHI (< 80% predicted). A reduced CHI was associated with increased circulating levels of IL-6 (p = 0.001), TNF-alpha (p = 0.032) and their soluble receptors IL-6sr (p = 0.002), TNF-alpha sr1 (p = 0.03), and TNF-alpha sr2 (p = 0.001). Patients with a normal BMI and low CHI had inflammatory mediator levels similar to patients with a low BMI and CHI; both were significantly greater than in those with a normal BMI and CHI. Nitrogen balance was similar between normal and low CHI groups, although nitrogen excretion was significantly increased in the low CHI group. Skeletal muscle loss in COPD is probably multifactorial in origin, but our data suggest a link with systemic inflammation, even when weight loss is inapparent.

We hypothesized that in patients with chronic obstructive pulmonary disease, loss of fat-free mass (FFM) and loss of bone mineral density (BMD) were related to (1) each other and may be clinically inapparent, (2) urinary markers of cellular and bone collagen protein breakdown, and (3) severity of lung disease. Eight-one patients and 38 healthy subjects underwent dual-energy X-ray absorptiometry to determine body composition and BMD. Urinary protein breakdown markers, inflammatory mediators, and their soluble receptors were determined. Thirty-three patients had a low fat-free mass index (kg/m(2)), 17 of whom had a normal body mass index. Thirty-two percent of patients (13% of healthy subjects) had osteoporosis at the hip or lumbar spine. The marker of cellular protein breakdown was elevated in patients and related to lung disease severity and body composition. The marker of bone collagen breakdown was greater in patients with osteoporosis. Inflammatory mediators were elevated in patients. Loss of FFM and loss of BMD were related, occurred commonly, and could be subclinical in patients with chronic obstructive pulmonary disease. Loss of both was greatest with severe lung disease. Increased excretion of cellular and bone collagen protein breakdown products in those with low FFM and BMD indicates a protein catabolic state in these patients.

Background-Pulmonary rehabilitation programmes improve the health of patients disabled by lung disease but their cost eVectiveness is unproved. We undertook a cost/utility analysis in conjunction with a randomised controlled clinical trial of pulmonary rehabilitation versus standard care. Methods-Two hundred patients, mainly with chronic obstructive pulmonary disease, were randomly assigned to either an 18 visit, 6 week rehabilitation programme or standard medical management. The diVerence between the mean cost of 12 months of care for patients in the rehabilitation and control groups (incremental cost) and the diVerence between the two groups in quality adjusted life years (QALYs) gained (incremental utility) were determined. The ratio between incremental cost and utility (incremental cost/utility ratio) was calculated. Results-Each rehabilitation programme for up to 20 patients cost £12 120. The mean incremental cost of adding rehabilitation to standard care was £ -152 (95% CI -881 to 577) per patient, p=NS. The incremental utility of adding rehabilitation was 0.030 (95% CI 0.002 to 0.058) QALYs per patient, p=0.03. The point estimate of the incremental cost/utility ratio was therefore negative. The bootstrapping technique was used to model the distribution of cost/utility estimates possible from the data. A high likelihood of generating QALYs at negative or relatively low cost was indicated. The probability of the cost per QALY generated being below £0 was 0.64. Conclusions-This outpatient pulmonary rehabilitation programme produces cost per QALY ratios within bounds considered to be cost eVective and is likely to result in financial benefits to the health service. (Thorax 2001;56:779-784)

Attendance at PRPs is independently influenced by smoking status, the degree of breathlessness, frequency of hospital admissions, length of the programme and journey time.

Background Mitral annular disjunction (MAD) is a structural abnormality where there is a separation between the mitral valve annulus and the left atrial wall which is not well understood. Methods We conducted a systematic review to evaluate the prevalence of MAD, factors associated with MAD and clinical outcomes among patients with MAD. Results A total of 19 studies were included in this review, and the number of noncase report studies had between 23 and 1439 patients. The pooled rate of MAD in studies of myxomatous mitral valve patients was 66/130 (50.8%, 3 studies), and among patients with mitral valve prolapse was 95/291 (32.6%, 3 studies). One study suggests that 78% of patients with MAD had mitral valve prolapse, and another suggested it was strongly associated with myxomatous mitral valve disease (HR 5.04 95% CI 1.66–15.31). In terms of clinical significance, it has been reported that MAD with disjunction > 8.5 mm was associated with nonsustained ventricular tachycardia (OR 10 95% CI 1.28–78.1). There is also evidence that gadolinium enhancement in papillary muscle (OR 4.09 95% CI 1.28–13.05) and longitudinal MAD distance in posterolateral wall (OR 1.16 95% CI 1.02–1.33) was predictive of ventricular arrhythmia and late gadolinium enhancement in anterolateral papillary muscle was strongly associated with serious arrhythmic event (OR 7.35 95% CI 1.15–47.02). Conclusions Mitral annular disjunction appears to be common in myxomatous mitral valve disease and mitral valve prolapse which can be detected on cardiac imaging and may be important because of its association with ventricular arrhythmias and sudden cardiac death.

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1. We have studied the carotid body contribution to hypoxic respiratory drive, using a hypoxic/hyperoxic switching technique, and the ventilatory response to intravenous infusion of adenosine, a recently described respiratory stimulant, in five patients with bilateral carotid endarterectomy. 2. The contribution made by the carotid bodies to total ventilatory drive during hypoxia varied from 2.5% to 45.9%. 3. The ventilatory response to adenosine infusion varied from a 7% decrease to a 25% increase in ventilation. 4. Those patients with intact hypoxic ventilatory drive showed respiratory stimulation, whereas of the two patients with attenuated chemoreflexes, one showed no stimulation and the other depression of ventilation in response to adenosine infusion. 5. We conclude that adenosine exerts its respiratory stimulant effect via an action on the peripheral chemoreceptors. This may coexist with a centrally mediated respiratory depression that is masked when the carotid bodies are intact.