Posted by Netch on March 21, 2009, at 5:47:27
In reply to Re: Interleukin-6 Elevated in Suicide Attempters, posted by desolationrower on March 9, 2009, at 17:26:43
MAJOR DEPRESSION IS ASSOCIATED WITH SIGNIFICANT DIURNAL ELEVATIONS IN PLASMA IL-6 LEVELS, A SHIFT OF ITS CIRCADIAN RHYTHM, AND LOSS OF PHYSIOLOGIC COMPLEXITY IN ITS SECRETION: CLINICAL IMPLICATIONS
BACKGROUND. Major depressive disorder (MDD) is associated with increased risk for premature coronary heart disease (CHD) and bone loss. Single time measurements of plasma IL-6, a good predictor of future risk for both cardiovascular disease and osteoporosis, revealed significant elevations in depressed patients. The objective of this study was to rigorously compare plasma IL-6 levels, measured over 24 h, in MDD patients and healthy controls. Given the activating role of IL-6 on the hypothalamic-pituitary-adrenal (HPA) axis, and the relevance of its dysregulation in MDD, we also analyzed the relations between IL-6 and cortisol levels. METHODS. We studied 9 patients and 9 controls, individually matched by gender, age (± 5 yr), BMI (± 2 kg/m2) and menstrual cycle phase. Diagnosis of MDD was confirmed by structured clinical interview (SCID-I for DSM-IV). Self-reported mood ratings were assessed by multiple visual analog scales (MVAS). The rhythmicity and complexity of IL-6 and cortisol secretion were tested by cosinor analyses, approximate entropy (ApEn) and cross-approximate entropy (Cross-ApEn) algorithms. RESULTS. MDD patients had significant mean IL-6 elevations from 1000 h to 1200 h, and at 1500 h (p ranging from <0.05 to <0.01), vs. controls. In addition, in MDD, the circadian rhythm of IL-6 was shifted by 12 h, and its physiologic complexity was reduced, with no difference in the Cross-ApEn of IL-6 and cortisol between the two groups, and significant time-lagged correlations only in the controls. IL-6 levels correlated significantly with mood-ratings. CONCLUSIONS. We report profound morning elevations of plasma IL-6 and a reversal of its circadian rhythm in MDD patients, in the absence of hypercortisolism. These findings may be relevant to the increased risk for CHD and bone loss in MDD.
poster:Netch
thread:884576
URL: http://www.dr-bob.org/babble/neuro/20090129/msgs/886357.html