Low-grade inflammation in depression, anxiety and sleep disturbances

• Main Author: Liukkonen, T. (Timo)
• Other Authors: Timonen, M. (Markku), Räsänen, P. (Pirkko)
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: Oulun yliopisto 2011
• Subjects: C-reactive protein; anxiety disorders; cohort studies; depressive disorder; hormone replacement therapy; low-grade inflammation; oral contraceptives; sleep disorders; ahdistus; c-reaktiivinen proteiini; depressio; hormonaalinen ehkäisy; hormonikorvaushoito; kohorttitutkimus; matala-asteinentulehdustila; unihäiriö; Matala; Northern Finland
• Online Access: http://urn.fi/urn:isbn:9789514296475

Abstract Depression, anxiety and sleep disorders have been reported to be associated with low level of inflammation, i.e., low-grade inflammation, but mainly in males. The evidence has mainly been based on laboratory or clinical studies with small sample sizes or epidemiological studies with elderly subpopulations. In this study the association of low-grade inflammation with depression, anxiety, and sleep disturbances was investigated using the Northern Finland 1966 Birth Cohort (NFBC 1966). In women, the effect of hormonal factors, menopause and the use of oral contraceptives/hormone replacement therapy on the association between low-grade inflammation and depression was also studied by using the Pieksämäki Study data. In 31-year follow-up of NFBC 1966 (N=6007), the depressive and anxiety symptoms were assessed by Hopkins Symptom Checklist-25 (HSCL-25) and sleep disorders by 15-D questionnaires, while the marker of low-grade inflammation, plasma concentration of high sensitivity C-reactive protein (hs-CRP), was measured. In the Pieksämäki study a representative sample of inhabitants in the town of Pieksämäki were invited to clinical examination. Depressive symptoms were obtained by Beck’s Depression Inventory-21, and hs-CRP was measured (512 women). The results of this study revealed that at epidemiological level, elevated hs CRP levels of ≥1.0 mg/L increased the probability of current depressive symptoms of single depressive episode in the two highest subgroups (i.e., HSCL-25 mean scores ≥1.75 and ≥2.01) 1.4- and 1.7- fold in males, respectively. In addition, anxiety symptoms (HSCL-25 anxiety scale mean score ≥1.75) increased independently the probability of elevated hs-CRP levels (>3.0 mg/L) in males over 2-fold. Risk ratio of 1.3 was found for males with moderate to severe sleep disturbances and elevated hs-CRP levels (≥1.0 mg/L). Regarding females, a positive correlation between elevated hs-CRP levels and depressive symptoms was found only among peri- and postmenopausal women not using exogenous ...