Cerebrospinal fluid interleukin (IL)-6 in unipolar major depression.
BACKGROUND
Previous studies have suggested that regulation of the proinflammatory cytokine interleukin (IL)-6 is abnormal in patients with major depression. This study was undertaken to determine whether IL-6 concentrations in cerebrospinal fluid (CSF) differ between depressed patients and healthy control subjects.


METHODS
Lumbar puncture with a standardized procedure was performed on 18 drug-free patients meeting DSM-IV criteria for unipolar major depression and 26 age- and sex-matched healthy volunteers. CSF was assayed for IL-6 using a quantitative 'sandwich' enzyme immunoassay technique.


RESULTS
Mean+/-S.D. CSF IL-6 levels did not differ between depressed (2.2+/-1.0 pg/ml) and healthy control (2.4+/-1.9 pg/ml) subjects.


CONCLUSIONS
This study had adequate power (0.8) to detect a large (d=0.88) effect size at alpha = 0.05. Although sample sizes were comparable to or larger than those of previous CSF studies, it is possible that a less robust difference between depressed and healthy subjects was not detected.


CONCLUSIONS
These findings fail to support speculation that immune activation may be causally involved in the pathogenesis of depression.
Carpenter
Linda L
LL
Mood Disorders Research Program, Butler Hospital, and Department of Psychiatry and Human Behavior, Brown Medical School, Providence, RI, USA. linda_carpenter_md@brown.edu
Heninger
George R
GR
Malison
Robert T
RT
Tyrka
Audrey R
AR
Price
Lawrence H
LH
D000293:Adolescent; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000032:analysis; D016022:Case-Control Studies; D003866:Depressive Disorder / Q000276:immunology* / Q000503:physiopathology; D005260:Female; D006801:Humans; D015850:Interleukin-6 / Q000134:cerebrospinal fluid*; D008297:Male; D008875:Middle Aged; D013129:Spinal Puncture
D015415:Biomarkers; D015850:Interleukin-6