Low and high serum IgG associates with respiratory infections in a young and working age populationResearch in context
Pia Holma,
Paula Pesonen,
Minna K. Karjalainen,
Marjo-Riitta Järvelin,
Sara Väyrynen,
Eeva Sliz,
Anni Heikkilä,
Mikko R.J. Seppänen,
Johannes Kettunen,
Juha Auvinen,
Timo Hautala
Affiliations
Pia Holma
Research Unit of Internal Medicine and Biomedicine, University of Oulu and Oulu University Hospital, Division of Infectious Diseases, Oulu, Finland
Paula Pesonen
Northern Finland Birth Cohorts, Arctic Biobank, Infrastructure for Population Studies, Faculty of Medicine, University of Oulu, Oulu, Finland
Minna K. Karjalainen
Northern Finland Birth Cohorts, Arctic Biobank, Infrastructure for Population Studies, Faculty of Medicine, University of Oulu, Oulu, Finland; Research Unit of Population Health, Faculty of Medicine, University of Oulu, Oulu, Finland
Marjo-Riitta Järvelin
Research Unit of Population Health, Faculty of Medicine, University of Oulu, Oulu, Finland; Department of Epidemiology and Biostatistics, MRC Center for Environment & Health, School of Public Health, Imperial College London, London, UK
Sara Väyrynen
Research Unit of Internal Medicine and Biomedicine, University of Oulu and Oulu University Hospital, Division of Infectious Diseases, Oulu, Finland
Eeva Sliz
Research Unit of Population Health, Faculty of Medicine, University of Oulu, Oulu, Finland
Anni Heikkilä
Research Unit of Population Health, Faculty of Medicine, University of Oulu, Oulu, Finland
Mikko R.J. Seppänen
Rare Disease Center and Pediatric Research Center, Children and Adolescents, University of Helsinki and HUS Helsinki University Hospital, Helsinki, Finland
Johannes Kettunen
Research Unit of Population Health, Faculty of Medicine, University of Oulu, Oulu, Finland
Juha Auvinen
Research Unit of Population Health, Faculty of Medicine, University of Oulu, Oulu, Finland
Timo Hautala
Research Unit of Internal Medicine and Biomedicine, University of Oulu and Oulu University Hospital, Division of Infectious Diseases, Oulu, Finland; Corresponding author. Research Unit of Biomedicine, University of Oulu, P.O. Box 20, FIN-90029 OYS, Finland.
Summary: Background: We investigated health consequences and genetic properties associated with serum IgG concentration in a young and working age general population. Methods: Northern Finland Birth Cohort 1966 (NFBC1966, n = 12,231) health data have been collected from birth to 52 years of age. Relationships between life-long health events, medications, chronic conditions, lifestyle, and serum IgG concentration measured at age 46 years (n = 5430) were analysed. Regulatory mechanisms of serum IgG concentration were considered. Findings: Smoking and genetic variation (FCGR2B and TNFRSF13B) were the most important determinants of serum IgG concentration. Laboratory findings suggestive of common variable immunodeficiency (CVID) were 10-fold higher compared to previous reports (73.7 per 100,000 vs 0.6–6.9 per 100,000). Low IgG was associated with antibiotic use (relative risk 1.285, 95% CI 1.001–1.648; p = 0.049) and sinus surgery (relative risk 2.257, 95% CI 1.163–4.379; p = 0.016). High serum IgG was associated with at least one pneumonia episode (relative risk 1.737, 95% CI 1.032–2.922; p = 0.038) and with total number of pneumonia episodes (relative risk 2.167, 95% CI 1.443–3.254; p < 0.001). Interpretation: CVID-like laboratory findings are surprisingly common in our unselected study population. Any deviation of serum IgG from normal values can be harmful; both low and high serum IgG may indicate immunological insufficiency. Critical evaluation of clinical presentation must accompany immunological laboratory parameters. Funding: Oulu University Hospital VTR, CSL Behring, Foundation for Pediatric Research.
