Factors related to environmental influences on a farm such as increased exposure to bacterial compounds in stables where livestock is kept prevent the development of allergic disorders in children.

Background Asthma is a growing public health problem in developing countries. However, few studies have studied the role of urbanisation in this phenomenon. It was hypothesised that children living in a peri-urban setting in Peru have higher rates of asthma and allergy than rural counterparts. Methods 1441 adolescents aged 13–15 years were enrolled from two settings: a peri-urban shanty town in Lima (n=725) and 23 rural villages in Tumbes (n=716). Participants filled in questionnaires on asthma and allergy symptoms, environmental exposures and sociodemographics, and underwent spirometry, and exhaled nitric oxide (eNO) and allergy skin testing. Indoor particulate matter (PM) concentrations were measured in 170 households. Results Lima adolescents had higher rates of lifetime wheezing (22% vs 10%), current asthma symptoms (12% vs 3%) and physician-diagnosed asthma (13% vs 2%; all p <0.001). Current rhinitis (23% vs 12%), eczema (12% vs 0.4%), atopy (56% vs 38%), personal history of cigarette smoking (7.4% vs 1.3%) and mean indoor PM (31 vs 13 μg/m3) were also higher in Lima (all p <0.001). The peri-urban environment of Lima was associated with a 2.6-fold greater odds (95% CI 1.3 to 5.3) of asthma in multivariable regression. Forced expiratory volumes were higher and FEV1/FVC (forced expiratory volume in 1 s/forced vital capacity) ratios were lower in Lima (all p <0.001). Higher eNO values in Lima (p <0.001) were attributable to higher rates of asthma and atopy. Conclusions Peri-urban adolescents had more asthma, atopy and airways inflammation and were exposed to more indoor pollution. The findings provide evidence of the risks posed to lung health by peri-urban environments in developing countries.

Our purpose was to assess the cost, quality of life impact, and the cost-utility of bariatric surgery in a managed care population. We studied 221 patients who underwent bariatric surgery between 2001 and 2005. We analyzed medical claims data for all patients and survey data for 122 survey respondents (55% response rate). Patients were generally middle-aged, female, and white. Sixty-four percent underwent open and 33% underwent laparoscopic Roux-en-Y procedures. One year after surgery, mean body mass index fell from 51 to 31 kg/m(2) in women and from 59 to 35 kg/m(2) in men with substantial improvements in comorbidities. Postsurgical mortality and morbidity were low. Total per member per month costs increased in the 6 months before bariatric surgery, were lower in the 12 months after bariatric surgery, but increased somewhat over the next 12 months. When presurgical quality of life was assessed prospectively, average health utility scores improved by 0.14 one year after surgery. In analyses that took a lifetime time horizon, projected future costs based on age and obesity and discounted costs and health utilities at 3% per year, the cost-utility ratio for bariatric surgery versus no surgery was approximately $1,400 per quality-adjusted life-year gained. In sensitivity analyses, bariatric surgery was more cost-effective in women, non-whites, more obese patients, and when performed laparoscopically. Although not cost-saving, bariatric surgery represents a very good value for money. Its long-term cost effectiveness appears to depend on the natural history and cost of late postsurgical complications and the natural history and cost of untreated morbid obesity.

Background Vitamin D deficiency may be associated with an increased risk of asthma. Objective We studied the association between 25-hydroxy (25-OH) vitamin D deficiency and asthma prevalence in two Peruvian populations close to the equator but with disparate degrees of urbanization. Methods We conducted a population-based study in 1441 children in two communities in Peru, of which 1134 (79%) provided a blood sample for 25-OH vitamin D analysis. Results In these 1134 children, mean age was 14.8 years; 52% were boys; asthma and atopy prevalence were 12% in Lima vs. 3% in Tumbes (p<0.001) and 59% in Lima vs. 41% in Tumbes (p<0.001), respectively; and, mean 25-OH vitamin D was 20.8 ng/mL in Lima vs. 30.1 ng/mL in Tumbes (p<0.001). Prevalence of 25-OH vitamin D deficiency (<20 ng/mL) was 47% in Lima vs. 7% in Tumbes (p<0.001). In multivariable logistic regression, we found that lower 25-OH vitamin D levels were associated with an increased odds of asthma (OR = 1.7 per each 10 ng/mL decrease in 25-OH vitamin D levels, 95% CI 1.2 to 2.6; p<0.01). In stratified analyses, the association between lower 25-OH vitamin D levels and asthma was limited to children with atopy (OR=2.2, 95% CI 1.3 to 3.6) and not in those without atopy (OR=0.9, 95% CI 0.5 to 2.0). We did not find associations between 25-OH vitamin D levels and other clinical biomarkers for asthma, including exhaled nitric oxide, total serum IgE and pulmonary function. Conclusion and Clinical Relevance Both asthma and 25-OH vitamin D deficiency were common among children living in Lima (latitude=12.0°S) but not among those in Tumbes (3.6°S). The relationship between 25-OH vitamin D deficiency and asthma was similar in both sites and was limited among children with atopy. Future supplementation trials may need to consider stratification by atopy at the time of design.