Insulin resistance, metabolic syndrome, and lung function in US adolescents with and without asthma.
BACKGROUND
Obesity increases both the risk of asthma and asthma severity and is a well-known risk factor for insulin resistance and the metabolic syndrome (MS) in children and adolescents.


OBJECTIVE
We aimed to examine the association among obesity, insulin sensitivity, MS, and lung function in US adolescents with and without asthma.


METHODS
We performed a cross-sectional study of 1429 adolescents aged 12 to 17 years in the 2007-2010 National Health and Nutrition Examination Survey. Adjusted regression was used to assess the relationships among obesity, insulin sensitivity/resistance, MS, and lung function in children with and without asthma.


RESULTS
Insulin resistance was negatively associated with FEV1 and forced vital capacity (FVC) in adolescents with and without asthma, whereas MS was associated with lower FEV1/FVC ratios, with a more pronounced decrease found among asthmatic patients; these associations were driven by overweight/obese adolescents. Higher body mass index was associated with a decrease in FEV1/FVC ratios among adolescents with insulin resistance. Compared with healthy participants, adolescents with MS had an approximately 2% decrease in FEV1/FVC ratios, adolescents with asthma had an approximately 6% decrease, and those with MS and asthma had approximately 10% decreased FEV1/FVC ratios (P < .05).


CONCLUSIONS
Insulin resistance and MS are associated with worsened lung function in overweight/obese adolescents. Asthma and MS synergistically decrease lung function, as do obesity and insulin resistance. These factors might contribute to the pathogenesis of asthma severity in obese patients and warrant further investigation.
Division of Pediatric Pulmonary Medicine, Allergy, and Immunology, Children's Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine, Pittsburgh, Pa. Electronic address: erick.forno@chp.edu.
Erick
E
Forno
Division of Pediatric Pulmonary Medicine, Allergy, and Immunology, Children's Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine, Pittsburgh, Pa.
Yueh-Ying
YY
Han
Division of Pediatric Endocrinology, Children's Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine, Pittsburgh, Pa.
Radhika H
RH
Muzumdar
Division of Pediatric Pulmonary Medicine, Allergy, and Immunology, Children's Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine, Pittsburgh, Pa.
Juan C
JC
Celedón
D000293:Adolescent; D001249:Asthma / Q000150:complications* / Q000175:diagnosis / Q000378:metabolism / Q000503:physiopathology; D015992:Body Mass Index; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D007333:Insulin Resistance; D008297:Male; D024821:Metabolic Syndrome / Q000150:complications* / Q000175:diagnosis / Q000378:metabolism / Q000503:physiopathology; D009749:Nutrition Surveys; D009765:Obesity / Q000150:complications* / Q000175:diagnosis / Q000378:metabolism / Q000503:physiopathology; D014481:United States; D014797:Vital Capacity
Asthma; National Health and Nutrition Examination Survey; adiposity; insulin resistance; lung function; metabolic syndrome; obesity