Cost-effectiveness of continuous positive airway pressure therapy in patients with obstructive sleep apnea-hypopnea in British Columbia

BACKGROUND:

Obstructive sleep apnea-hypopnea (OSAH) is a common disorder characterized by recurrent collapse of the upper airway during sleep. Patients experience a reduced quality of life and an increased risk of motor vehicle crashes (MVCs). Continuous positive airway pressure (CPAP), which is the first-line therapy for OSAH, improves sleepiness, vigilance and quality of life.

OBJECTIVE:

To assess the cost-effectiveness of CPAP therapy versus no treatment for OSAH patients who are drivers.

METHODS:

A Markov decision analytical model with a five-year time horizon was used. The study population consisted of male and female patients, between 30 and 59 years of age, who were newly diagnosed with moderate to severe OSAH. The model evaluated the cost-effectiveness of CPAP therapy in reducing rates of MVCs and improving quality of life. Utility values were obtained from previously published studies. Rates of MVCs under the CPAP and no CPAP scenarios were calculated from Insurance Corporation of British Columbia data and a systematic review of published studies. MVCs, equipment and physician costs were obtained from the British Columbia Medical Association, published cost-of-illness studies and the price lists of established vendors of CPAP equipment in British Columbia. Findings were examined from the perspectives of a third-party payer and society.

RESULTS:

From the third-party payer perspective, CPAP therapy was more effective but more costly than no CPAP (incremental cost-effectiveness ratio [ICER] of $3,626 per quality-adjusted life year). From the societal perspective, the ICER was similar ($2,979 per quality-adjusted life year). The ICER was most dependent on preference elicitation method used to obtain utility values, varying almost sixfold under alternative assumptions from the base-case analysis.

CONCLUSION:

After considering costs and impact on quality of life, as well as the risk of MVCs in individuals with OSAH, CPAP therapy for OSAH patients is a highly efficient use of health care resources. Provincial governments who do not provide funding for CPAP therapy should reconsider.     

Modulatory effect of the SLC9A3 gene on susceptibility to infections and pulmonary function in children with cystic fibrosis

In cystic fibrosis (CF), CFTR dysfunction leads to salt and water imbalance across airway epithelia, depleted surface liquid layer, and impaired mucociliary clearance. This provides optimal conditions for chronic bacterial infections leading to excessive inflammation and progressive obstructive lung disease. We hypothesized that other epithelial channels affecting salt balance across the airways may play a role in the susceptibility to bacterial infections and modulate severity of CF lung disease. The SLC9A3 gene encoding a Na⁺/H⁺ exchanger was demonstrated to be a modifier intestinal disease in a murine model of CF. We examined the potential role of SLC9A3 as a modifier of CF lung disease severity. We analyzed 11 SLC9A3 gene variants for association with age of first Pseudomonas aeruginosa infection and lung function in children with CF. The T allele of an intronic variant in the SLC9A3 gene (rs4957061) was significantly (P = 0.02) associated with earlier acquisition of Pseudomonas infection in a cohort of 1,004 pediatric patients. Analysis of lung function in a subset of these patients (752) revealed that patients homozygous for the T allele had substantially reduced lung function and accelerated rate of decline. Although the functional basis for the modulatory effects of this SLC9A3 variant on CF lung disease remains to be elucidated, altered function of the Na⁺/H⁺ exchanger may further deplete the airway liquid surface, thereby enhancing susceptibility to Pseudomonas infections and worsening the severity of lung disease. Pediatr Pulmonol. 2011; 46:385–392. © 2010 Wiley‐Liss, Inc.     

Multicenter randomized controlled trial of withdrawal of inhaled corticosteroids in cystic fibrosis

RATIONALE: Lung inflammation and injury is critical in cystic fibrosis. An ideal antiinflammatory agent has not been identified but inhaled corticosteroids are widely used despite lack of evidence. OBJECTIVES: To test the safety of withdrawal of inhaled corticosteroids with the hypothesis this would not be associated with an earlier onset of acute chest exacerbations. METHODS: Multicenter randomized double-blind placebo-controlled trial in 18 pediatric and adult UK centers. Eligibility criteria included age>6.0 yr, FEV1>or=40% predicted, and corticosteroid use>3 mo. During the 2-mo run-in period, all patients received fluticasone; they then took either fluticasone or placebo for 6 mo. MEASUREMENTS AND MAIN RESULTS: Fluticasone group: n=84, median age 14.6 yr, mean (SD) FEV1 76% (18); placebo group: n=87, median age 15.8 yr, mean (SD) FEV1 76% (18). There was no difference in time to first exacerbation (primary outcome) with hazard ratio (95% confidence interval) of 1.07 (0.68 to 1.70) for fluticasone versus placebo. There was no effect of age, atopy, corticosteroid dose, FEV1, or Pseudomonas aeruginosa status. There was no change in lung function or differences in antibiotic or rescue bronchodilator use. Fewer patients in the fluticasone group withdrew from the study due to lung-related adverse events (9 vs. 15%); with a relative risk (95% confidence interval) of 0.59 (0.23-1.48) fluticasone versus placebo. CONCLUSIONS: In this study population (applicable to 40% of patients with cystic fibrosis in the UK), it appears safe to consider stopping inhaled corticosteroids. Potential advantages will be to reduce the drug burden on patients, reduce adverse effects, and make financial savings.     

Patients prefer sedation for fibreoptic bronchoscopy

Abstract This study was carried out in order to determine if intravenous (i.v.) sedation with diazepam, at the time of procedure, made fibreoptic bronchoscopy more tolerable and if these perceptions persisted on later questioning. Methodology consisted of a sequential, parallel group design comparing sedation with no sedation for bronchoscopy in a tertiary referral hospital. Patient comfort and sedation desired for hypothetical repeat bronchoscopy were assessed both immediately and after at least 1 month. Patients who received sedation rated bronchoscopy as more comfortable ( P =0.01). Those who received sedation were also more likely to want no change in sedation if the bronchoscopy were repeated ( P <0.01). These differences were more evident at later questioning. Sedation was not associated with an increased complication rate but was associated with a prolonged recovery room stay (no sedation, 19.2 min (SEM 3.8) compared with sedation, 76.1 min (5.4), P <0.001). In contrast to previous studies, our patients found bronchoscopy more comfortable with i.v. diazepam sedation. This was supported by patients who received sedation being less likely to want any change in future sedation if a repeat bronchoscopy were required. The benefit seen with sedation was more marked at later questioning supporting a previously postulated amnesic effect. However, sedation was associated with a prolonged room stay and potentially greater attendant cost.