Systemic lupus erythematosus in a multiethnic US cohort (LUMINA) XL II: factors predictive of new or worsening proteinuria.
OBJECTIVE
To determine the factors predictive of new or worsening proteinuria in a large multiethnic cohort of patients with systemic lupus erythematosus (SLE).


METHODS
Five hundred and twenty-nine SLE patients from a multiethnic US cohort [LUpus in MInorities: NAture versus Nurture (LUMINA)] were evaluated for new or worsening proteinuria using the categories of the Systemic Lupus Activity Measure-Revised: (1), normal; (2), trace or 1+ proteinuria on the dipstick; (3), 2-3+ proteinuria and (4), > or =4+ proteinuria. A rise in urinary protein was considered a positive event visit. Basic demographic and socioeconomic variables were assessed at baseline (T0). Clinical and immunological variables including disease features, activity, duration, comorbidities (such as hypertension and diabetes), medications and autoantibodies were assessed at the visit preceding a positive event visit. Selected HLA-DR and HLA-DQ alleles, and FCGR receptor polymorphisms were assessed. Data were analysed using logistic regression analyses and generalized estimating equations.


RESULTS
There were 243 patients (59.1% of 93 Texan Hispanics, 37.0% of 100 Puerto Rican Hispanics, 58.0% of 181 African Americans and 29.7% of 155 Caucasians) with new or worsening proteinuria, and 364 positive events in 2801 visits. Younger age [Odds ratio (OR) = 1.013, 95% confidence limits (CL) = 1.001-1.024, P < 0.0334], anti-dsDNA (OR = 1.554, CL = 1.149-2.100, P < 0.0042), and HLA-DRB1*1503 (OR = 1.746, 95% CL = 1.573-2.2673, P < 0.0103) were found to independently predict the occurrence of new or worsening proteinuria.


CONCLUSIONS
The factors predictive of new or worsening proteinuria include traditional factors associated with lupus nephritis, such as age and anti-dsDNA, as well as HLA-DRB1*1503, which has not been previously described in association with lupus nephritis, new or worsening proteinuria.
Bastian
H M
HM
Department of Medicine, Division of Clinical Immunology and Rheumatology, The University of Alabama, Birmingham, USA.
Alarcón
G S
GS
Roseman
J M
JM
McGwin
G
G
Vilá
L M
LM
Fessler
B J
BJ
Reveille
J D
JD
D000328:Adult; D001741:Black or African American; D000367:Age Factors; D000974:Antibodies, Antinuclear / Q000097:blood; D004247:DNA / Q000276:immunology; D018450:Disease Progression; D005260:Female; D020022:Genetic Predisposition to Disease; D006684:HLA-DR Antigens / Q000235:genetics; D059811:HLA-DRB1 Chains; D006630:Hispanic or Latino; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000208:ethnology / Q000235:genetics; D008181:Lupus Nephritis / Q000208:ethnology / Q000209:etiology* / Q000235:genetics; D008297:Male; D008875:Middle Aged; D011507:Proteinuria / Q000208:ethnology / Q000209:etiology* / Q000235:genetics; D012307:Risk Factors; D012720:Severity of Illness Index; D012959:Socioeconomic Factors; D014481:United States / Q000453:epidemiology; D044465:White People
D000974:Antibodies, Antinuclear; D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains; D004247:DNA