Open AccessObesity as a risk factor for severe influenza‐like illness
Author(s) -
Cocoros Noelle M.,
Lash Timothy L.,
DeMaria Alfred,
Klompas Michael
Publication year - 2014
Publication title -
influenza and other respiratory viruses
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.743
H-Index - 57
eISSN - 1750-2659
pISSN - 1750-2640
DOI - 10.1111/irv.12156
Subject(s) - medicine , obesity , body mass index , comorbidity , risk factor , influenza like illness , pandemic , cohort study , cohort , demography , emergency medicine , covid-19 , disease , immunology , virus , sociology , infectious disease (medical specialty)
Background Obesity was recognized as in independent risk factor for influenza during the 2009 H1N1 influenza pandemic. Objectives We evaluated the association between body mass index ( BMI ) and influenza‐like illness ( ILI ) during two non‐pandemic influenza seasons (2003–2004 and 2004–2005) and during the spring and fall waves of the 2009 H1N1 pandemic. Methods Adults with severe (inpatient) and mild (outpatient) ILI were compared to those without ILI using a case‐cohort design. The study was nested among those insured by a single health insurance company, receiving care from a large multispecialty practice. Data were collected from insurance claims and the electronic health record. The primary exposure was obesity ( BMI ≥ 30·0 kg/m 2 ). Results Across three seasons, the crude and adjusted OR s for obesity and severe ILI were 1·65 (95% CI 1·31, 2·08) and 1·23 (95% CI 0·97, 1·57), respectively. An association was observed for those aged 20–59 years (adjusted OR 1·92, 95% CI 1·26, 2·90), but not for those 60 and older (adjusted OR 1·08, 95% CI 0·80, 1·46). The adjusted OR s for obesity and severe ILI in 2003–2004, 2004–2005, and during H1N1 were 1·14 (95% CI 0·80, 1·64), 1·24 (95% CI 0·86, 1·79), and 1·76 (95% CI 0·91, 3·42), respectively. Among those with a Charlson Comorbidity Index score of zero, the adjusted OR s for 2003–2004, 2004–2005, and H1N1 were 1·60 (95% CI 0·93, 2·76), 1·43 (95% CI 0·80, 2·56), and 1·90 (95% CI 0·68, 5·27), respectively. Conclusions Our results suggest a small to moderate association between obesity and hospitalized ILI among adults.