Body Weight and Infectious Outcomes in Patients with Primary Immunodeficiency Diseases: Outcomes from within the US Immunodeficiency Network (USIDNET).
Sunday, March 6, 2016: 2:00 PM
Room 408A (Convention Center)
Melanie A. Ruffner, MD, PhD, ,
Rationale:  A growing body of evidence supports  complex role of body weight with infectious and inflammatory disease outcomes.  However, there have been no studies to date examining body weight as a modifying factor in primary immunodeficiency diseases (PIDD). The goal of this study is to estimate prevalence of obesity and underweight status in immunodeficient patients, and to determine if body weight is associated with a higher rate of infectious complications in patients with PIDD.

Methods: The USIDNET is a research consortium established to advance understanding of PIDD. The USIDNET database was queried for all patients with complete height and weight information; patients without this information were excluded. Additional demographic and clinical information, including infectious and medical complications were also obtained for each patient. 

Results: 512 adults (age>20) and 660 children (ages 2-20) had complete BMI data. 4.1% of adults had BMI>40, 21.4% had 40>BMI>30 and 5.7% were underweight with BMI<18.5. 13% of pediatric patients had BMI>95th percentile (obese) and 7.1% with BMI<5th percentile (underweight). There were variable associations between body weight and complications of PIDD within cohorts of patients divided by diagnosis.  For example, obesity was associated with increased frequency of sepsis (12% vs 6%, p=0.05) but not pneumonia in adults with CVID.  Conversely, in pediatric CVID patients, pneumonia was associated more frequently in underweight subjects, although this did not achieve significance (77% vs 45%, normoweight vs 32% obese, p=0.07)

Conclusions:  This retrospective data presents new associations between body weight and PIDD and argues for consideration of body weight in PIDD studies.