Serum albumin as a marker for disease activity in patients with systemic lupus erythematosus.
OBJECTIVE
To determine whether serum albumin reflects disease activity in patients with systemic lupus erythematosus (SLE) with and without nephritis (LN, LNN), and whether serum albumin could be a surrogate marker of SLE disease activity overall. There is currently no clinical "gold standard" in the assessment of disease activity in SLE.


METHODS
Patients with >or= 3 clinic visits within a maximum followup period of 10 years were selected from the University of Toronto Lupus Clinic database. Subjects were divided into 3 groups: LN-B, those with nephritis defined by histological findings on renal biopsies; LN-L, those with nephritis defined by laboratory abnormalities in the absence of biopsy; and LNN, those without nephritis. In a subanalysis, the renal groups were further stratified by proteinuria status. The associations of SLE-Disease Activity Index (SLEDAI-2K) with serum albumin and dsDNA were examined using the mixed model regression analysis.


RESULTS
A total of 1078 patients were studied: 89.1% female, 71.5% white, mean age 33.6 (SD 12.6) years, and with median baseline SLEDAI-2K of 8. Serum albumin was more significantly associated with SLEDAI in LN-B and LN-L. The association was also present but weaker in the LNN group. In all LN, the associations between serum albumin and SLEDAI-2K were stronger in those with proteinuria.


CONCLUSIONS
In patients with SLE, higher SLEDAI was associated with lower serum albumin levels.
Division of Health Care and Outcome Research, Toronto Western Research Institute, Toronto, Ontario, Canada.
Jonathan
J
Yip
Elaheh
E
Aghdassi
Jiandong
J
Su
Wendy
W
Lou
Heather
H
Reich
Joanne
J
Bargman
James
J
Scholey
Dafna D
DD
Gladman
Murray B
MB
Urowitz
Paul R
PR
Fortin
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D004185:Disability Evaluation; D005260:Female; D006304:Health Status; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000097:blood / Q000175:diagnosis* / Q000503:physiopathology; D008181:Lupus Nephritis / Q000097:blood / Q000175:diagnosis / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D012016:Reference Values; D012709:Serum Albumin / Q000378:metabolism*; D012720:Severity of Illness Index; D055815:Young Adult
D015415:Biomarkers; D012709:Serum Albumin