The effect of omega-3 fatty acids on bronchial hyperresponsiveness, sputum eosinophilia, and mast cell mediators in asthma.

BACKGROUND: Omega-3 fatty acid supplements have been reported to inhibit exercise-induced bronchoconstriction (EIB). It has not been determined whether omega-3 supplements inhibit airway sensitivity to inhaled mannitol, a test for bronchial hyperresponsiveness (BHR) and model for EIB in people with mild to moderate asthma. METHODS: In a double-blind, crossover trial, subjects with asthma who had BHR to inhaled mannitol (n = 23; 14 men; mean age, 28 years; one-half taking regular inhaled corticosteroids) were randomized to omega-3 supplements (4.0 g/d eicosapentaenoic acid and 2.0 g/d docosahexaenoic acid) or matching placebo for 3 weeks separated by a 3-week washout. The primary outcome was the provoking dose of mannitol (mg) to cause a 15% fall in FEV1 (PD15). Secondary outcomes were sputum eosinophil count, spirometry, Asthma Control Questionnaire (ACQ) score, serum triacylglyceride level, and lipid mediator profile in urine and serum. RESULTS: PD15 (geometric mean, 95% CI) to mannitol following supplementation with omega-3s (78 mg, 51-119 mg) was not different from placebo (88 mg, 56-139 mg, P = .5). There were no changes in sputum eosinophils (mean ± SD) in a subgroup of 11 subjects (omega-3, 8.4% ± 8.2%; placebo, 7.8% ± 11.8%; P = .9). At the end of each treatment period, there were no differences in FEV1 % predicted (omega-3, 85% ± 13%; placebo, 84% ± 11%; P = .9) or ACQ score (omega-3, 1.1% ± 0.5%; placebo, 1.1% ± 0.5%; P = .9) (n = 23). Omega-3s caused significant lowering of blood triglyceride levels and expected shifts in serum fatty acids and eicosanoid metabolites, confirming adherence to the supplements; however, no changes were observed in urinary mast cell mediators. CONCLUSIONS: Three weeks of omega-3 supplements does not improve BHR to mannitol, decrease sputum eosinophil counts, or inhibit urinary excretion of mast cell mediators in people with mild to moderate asthma, indicating that dietary omega-3 supplementation is not useful in the short-term treatment of asthma. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT00526357; URL: www.clinicaltrials.gov.

Hospitalization patterns and outcomes of infants with Influenza A(H1N1) in Kuwait.

INTRODUCTION: Infants represent an important risk group for influenza associated hospitalizations and mortality. This study evaluated the clinical presentations, hospitalization course and outcome of infants hospitalized with the pandemic influenza A H1N1 [Influenza A(H1N1)pdm09] in relation to their previous health status. METHODOLOGY: We conducted a retrospective chart review of hospitalized infants with laboratory-confirmed Influenza A(H1N1)pdm09 infection in two hospitals in Kuwait. Demographic characteristics, pre-existing high-risk medical conditions, clinical presentations, complications and mortality were analyzed. Previously healthy infants' data were compared with infants with pre-existing high-risk medical conditions for severity of the illness and outcome. RESULTS: We identified 62 infants comprising 32% of all admissions with Influenza A(H1N1)pdm09.  The median age ± SD was 7 ± 4 months.  Nineteen (31%) had pre-existing high-risk medical conditions. Complications were documented in 53% of previously healthy infants compared to 47% in high-risk infants.  Mean duration of hospitalization was 4.9 days in healthy infants and 6.7 for infants with high-risk medical conditions. Bacterial pneumonia complicated 7% of previously healthy infants compared to 26% with high-risk conditions (P = 0.03). Four infants (6.5%) required admission to the intensive care unit (ICU), of whom three had high risk medical condition. CONCLUSION: The majority of hospitalized infants with Influenza A(H1N1)pdm09 were previously healthy. Prolonged hospitalization, ICU admission and mortality were more observed in infants with high-risk medical conditions. According to the latest Advisory Committee on Immunization Practices (ACIP) recommendations, annual influenza vaccination is recommended for any child six months of age and older, particularly those with risk factors.