title: Serum S100B protein is associated with depressive symptoms in patients with end-stage renal disease.
abstract: OBJECTIVE
  Depression is associated with a poorer prognosis in patients with end-stage renal disease (ESRD). Increasing evidence indicates that glial pathology and blood-brain-barrier (BBB) dysfunction are involved in the pathophysiology of depression. S100B, a protein expressed in astro- and oligodendroglia in the human brain is considered a biomarker of depression. Our objective was to investigate the relationship between S100B and depressive symptoms in patients undergoing hemodialysis (HD).
  
  
  METHODS
  Seventy-eight Korean patients undergoing chronic HD without significant neurological issues participated in a cross-sectional observation study. Depressive symptoms were assessed with the Beck Depression Inventory-II (BDI-II), and serum S100B levels were measured using blood samples obtained prior to a mid-week HD session.
  
  
  RESULTS
  The mean age of patients was 59.0 years, and the mean dialysis duration was 51.7 months. About 45% of patients undergoing HD met criteria for depression (BDI-II≥20). Serum S100B levels were significantly higher in patients with depression compared with patients without depression (115.1±45.4 vs. 66.1±35.3 pg/mL, p<0.001). S100B (r=0.556, p<0.001) and high-sensitivity C-reactive protein (hs-CRP; r=0.422, p<0.001) and β2-microglobulin (r=0.391, p<0.001) levels were positively correlated with BDI-II scores. A multivariate regression analysis showed that both S100B and hs-CRP were significantly associated with BDI-II scores.
  
  
  CONCLUSIONS
  The results showed a close association between S100B and depressive symptoms in patients undergoing HD. However, the mechanisms underlying this relationship are currently unknown and warrant further investigation.
authors.affiliation: Department of Internal Medicine, Hallym University Sacred Heart Hospital, Anyang, Republic of Korea.
authors.forename: Jwa-Kyung
authors.initials: JK
authors.lastname: Kim
authors.forename: Sung Gyun
authors.initials: SG
authors.lastname: Kim
authors.forename: Hyung Jik
authors.initials: HJ
authors.lastname: Kim
authors.forename: Young Rim
authors.initials: YR
authors.lastname: Song
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002097:C-Reactive Protein / Q000378:metabolism; D003863:Depression / Q000097:blood* / Q000150:complications*; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood* / Q000150:complications*; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D009414:Nerve Growth Factors / Q000097:blood*; D011569:Psychiatric Status Rating Scales; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins / Q000097:blood*; D055815:Young Adult; D001613:beta 2-Microglobulin / Q000097:blood
chemical_list: D009414:Nerve Growth Factors; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins; C579160:S100B protein, human; D001613:beta 2-Microglobulin; D002097:C-Reactive Protein