Body Mass Index and Risk of Infections Among Women in the Danish National Birth Cohort

• Published in: American journal of epidemiology Vol. 183; no. 11; pp. 1008 - 1017
• Main Authors: Harpsøe, Maria C., Nielsen, Nete M., Friis-Møller, Nina, Andersson, Mikael, Wohlfahrt, Jan, Linneberg, Allan, Nohr, Ellen A., Jess, Tine
• Format: Journal Article
• Language: English
• Published: United States Oxford Publishing Limited (England) 01.06.2016
• Subjects: Acute Disease; Adult; Anti-Infective Agents - therapeutic use; Antimicrobial agents; Body Height; Body Mass Index; Body Weight; Communicable Diseases - drug therapy; Communicable Diseases - epidemiology; Denmark - epidemiology; Epidemiology; Female; Health Behavior; Health risks; Hospitalization; Humans; Incidence; Infectious diseases; Medical treatment; Obesity; Obesity - epidemiology; Overweight - epidemiology; Proportional Hazards Models; Prospective Studies; Respiratory tract; Respiratory Tract Infections - epidemiology; Risk Factors; Skin Diseases, Infectious - epidemiology; Socioeconomic Factors; Thinness - epidemiology; Denmark; infections; antimicrobial agents; body mass index; obesity; underweight
• ISSN: 0002-9262; 1476-6256; 1476-6256
• DOI: 10.1093/aje/kwv300

We investigated the possible association between body mass index (BMI; weight (kg)/height (m)(2)) and hospitalization or treatment for acute infection in a prospective cohort study. We linked 75,001 women enrolled in the Danish National Birth Cohort from 1996 to 2002, who had information on BMI and a broad range of confounders, to data on infectious diseases and use of antimicrobial agents from the National Patient Register and the Danish Prescription Register. Associations were tested using Cox proportional hazards models. During 12 years of follow-up, we observed a U-shaped association between baseline BMI and later hospitalization for 1) any infectious disease and 2) infections of the respiratory tract, whereas a dose-response relationship was seen for skin infections. The most pronounced associations were seen for acute upper respiratory infections at multiple and unspecified sites (underweight (BMI <18.5): hazard ratio (HR) = 4.26, 95% confidence interval (CI): 1.69, 10.7; obesity (BMI ≥30): HR = 3.64, 95% CI: 1.62, 8.18), erysipelas (obesity: HR = 5.19, 95% CI: 3.38, 7.95), and fungal infections (underweight: HR = 3.19, 95% CI: 1.53, 6.66). Slightly greater use of antimicrobials was observed among overweight (BMI 25-<30; HR = 1.08, 95% CI: 1.06, 1.10) and obese (HR = 1.21, 95% CI: 1.17, 1.24) women. Among Danish women, underweight and obesity were associated with increased risk of community-acquired infectious diseases, especially infections of the upper respiratory tract and skin.