Childhood interleukin-6, C-reactive protein and atopic disorders as risk factors for hypomanic symptoms in young adulthood: a longitudinal birth cohort study

Hayes, J.F., Khandaker, G.M., Anderson, J. , Mackay, D. , Zammit, S., Lewis, G., Smith, D.J. and Osborn, D.P.J. (2017) Childhood interleukin-6, C-reactive protein and atopic disorders as risk factors for hypomanic symptoms in young adulthood: a longitudinal birth cohort study. Psychological Medicine, 47(1), pp. 23-33. (doi: 10.1017/S0033291716001574) (PMID:27476619) (PMCID:PMC5197925)

Abstract

Background: There are no existing longitudinal studies of inflammatory markers and atopic disorders in childhood and risk of hypomanic symptoms in adulthood. This study examined if childhood: (1) serum interleukin-6 (IL-6) and C-reactive protein (CRP); and (2) asthma and/or eczema are associated with features of hypomania in young adulthood. Method: Participants in the Avon Longitudinal Study of Parents and Children, a prospective general population UK birth cohort, had non-fasting blood samples for IL-6 and CRP measurement at the age of 9 years (n = 4645), and parents answered a question about doctor-diagnosed atopic illness before the age of 10 years (n = 7809). These participants completed the Hypomania Checklist at age 22 years (n = 3361). Results: After adjusting for age, sex, ethnicity, socio-economic status, past psychological and behavioural problems, body mass index and maternal postnatal depression, participants in the top third of IL-6 values at 9 years, compared with the bottom third, had an increased risk of hypomanic symptoms by age 22 years [adjusted odds ratio 1.77, 95% confidence interval (CI) 1.10–2.85, p < 0.001]. Higher IL-6 levels in childhood were associated with adult hypomania features in a dose–response fashion. After further adjustment for depression at the age of 18 years this association remained (adjusted odds ratio 1.70, 95% CI 1.03–2.81, p = 0.038). There was no evidence of an association of hypomanic symptoms with CRP levels, asthma or eczema in childhood. Conclusions: Higher levels of systemic inflammatory marker IL-6 in childhood were associated with hypomanic symptoms in young adulthood, suggesting that inflammation may play a role in the pathophysiology of mania. Inflammatory pathways may be suitable targets for the prevention and intervention for bipolar disorder.

• Item Type: Articles
• Additional Information: <br>Acknowledgements:</br> We are extremely grateful to all the families who took part in this study, the midwives for their help in recruiting them, and the whole ALSPAC team, which includes interviewers, computer and laboratory technicians, clerical workers, research scientists, volunteers, managers, receptionists and nurses. The UK Medical Research Council and the Wellcome Trust (grant reference 102215/2/13/2) and the University of Bristol provide core support for ALSPAC. This publication is the work of all the authors in keeping with the authorship guidelines of the journal. J.F.H. and D.P.J.O. will serve as guarantors for the contents of this paper. J.F. H. had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis. J.F.H. is supported by a Medical Research Council Population Health Scientist Fellowship (grant code: MR/K021362/1).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Smith, Professor Daniel and Anderson, Dr Jana and Mackay, Professor Daniel
• Authors: Hayes, J.F., Khandaker, G.M., Anderson, J., Mackay, D., Zammit, S., Lewis, G., Smith, D.J., and Osborn, D.P.J.
• College/School: College of Medical Veterinary and Life Sciences > School of Health & Wellbeing > Public Health
• Journal Name: Psychological Medicine
• Publisher: Cambridge University Press
• ISSN: 0033-2917
• ISSN (Online): 1469-8978
• Published Online: 01 August 2016
• Copyright Holders: Copyright © 2016 Cambridge University Press
• First Published: First published in Psychological Medicine 47(1): 23-33
• Publisher Policy: Reproduced under a creative commons license