Self-reported sleep duration, white blood cell counts and cytokine profiles in European adolescents: The HELENA study

HELENA Study Group

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26 Citations (Scopus)


Background: Sleep patterns face important changes during adolescence. This can have implications for the immune system, which is regulated by the sleep-wake cycle, however, most studies relating sleep and immune system have been conducted on adults. Objective: To study the relationships between sleep duration, immune cell counts, and cytokines in European adolescents participating in the HELENA Cross-Sectional Study. Methods: Adolescents (12.5-17.5 years; n = 933; 53.9% girls) were grouped according to self-reported sleep duration into <8, 8-8.9 and ≥9 h/night. Blood samples were collected in the morning after an overnight fast to analyze counts of white blood cells (WBC), neutrophils, lymphocytes, monocytes, eosinophils, basophils, the lymphocyte subsets CD3+, CD4+, CD8+, CD45RA+, CD45RO+, CD3-CD16+56+ and CD19+, and concentrations of cortisol, CRP, IL-1, IL-2, IL-4, IL-5, IL-6, IL-10, TNF-α and IFN-γ. Pro-/anti-inflammatory and Th1/Th2 cytokine ratios were calculated. Immune parameters were correlated to sleep duration and compared between the three groups. Results: Sleep duration was negatively associated with cortisol levels and WBC, neutrophil, monocyte, CD4+ and CD4+CD45RO+ counts; in girls it is also negatively associated with IL-5 and IL-6 levels. The 8-8.9 h/night group presented the highest IL-4 values and the lowest pro-/anti-inflammatory and Th1/Th2 cytokine ratios. Conclusion: A sleep duration of 8-8.9 h/night was associated with a healthier immune profile in our adolescents.

Original languageEnglish
Pages (from-to)1251-1258
Number of pages8
JournalSleep Medicine
Issue number10
Publication statusPublished - Jan 1 2014



  • Adolescents
  • Cytokine balance
  • Gender differences
  • Immune cell profile
  • Inflammation
  • Sleep duration
  • Th1/Th2

ASJC Scopus subject areas

  • Medicine(all)

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