Dietary intake, lung function and airway inflammation in Mexico City school children exposed to air pollutants

• Published in: Respiratory research Vol. 10; no. 1; p. 122
• Main Authors: Romieu, Isabelle, Barraza-Villarreal, Albino, Escamilla-Núñez, Consuelo, Texcalac-Sangrador, Jose L, Hernandez-Cadena, Leticia, Díaz-Sánchez, David, De Batlle, Jordi, Del Rio-Navarro, Blanca E
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 10-12-2009; BioMed Central; BMC
• Subjects: Air Pollutants; Air pollution; Analysis; Asthma; Asthma - diagnosis; Asthma - drug therapy; Asthma - epidemiology; Child; Children; Children & youth; Clinical trials; Data collection; Development and progression; Diet; Diet, Mediterranean - statistics & numerical data; Diets; Eating; Elementary school students; Environmental Exposure - statistics & numerical data; Female; Fruits; Fruits (Food); Health aspects; Hospitals; Humans; Incidence; Inflammation; Ingestion; Interleukins; Male; Mediterranean diet; Mexico - epidemiology; Monitoring systems; Nitric oxide; Nitrogen dioxide; Nutrition research; Outdoor air quality; Ozone; Pollutants; Prevention; Respiratory function; Respiratory Function Tests - statistics & numerical data; Risk Assessment; Risk Factors; Students - statistics & numerical data; Treatment Outcome; Urban areas; Vegetables; Vitamin C; Mexico; MED; Mexico, Distrito Federal, Mexico City
• ISSN: 1465-993X; 1465-9921; 1465-993X; 1465-9921
• DOI: 10.1186/1465-9921-10-122

Air pollutant exposure has been associated with an increase in inflammatory markers and a decline in lung function in asthmatic children. Several studies suggest that dietary intake of fruits and vegetables might modify the adverse effect of air pollutants.
A total of 158 asthmatic children recruited at the Children's Hospital of Mexico and 50 non-asthmatic children were followed for 22 weeks. Pulmonary function was measured and nasal lavage collected and analyzed every 2 weeks. Dietary intake was evaluated using a 108-item food frequency questionnaire and a fruit and vegetable index (FVI) and a Mediterranean diet index (MDI) were constructed. The impact of these indices on lung function and interleukin-8 (IL-8) and their interaction with air pollutants were determined using mixed regression models with random intercept and random slope.
FVI was inversely related to IL-8 levels in nasal lavage (p < 0.02) with a significant inverse trend (test for trend p < 0.001), MDI was positively related to lung function (p < 0.05), and children in the highest category of MDI had a higher FEV1 (test for trend p < 0.12) and FVC (test for trend p < 0.06) than children in the lowest category. A significant interaction was observed between FVI and ozone for FEV1 and FVC as was with MDI and ozone for FVC. No effect of diet was observed among healthy children.
Our results suggest that fruit and vegetable intake and close adherence to the Mediterranean diet have a beneficial effect on inflammatory response and lung function in asthmatic children living in Mexico City.