Prognosis in proliferative lupus nephritis: the role of socio-economic status and race/ethnicity

Nephrol Dial Transplant. 2003 Oct;18(10):2039-46. doi: 10.1093/ndt/gfg345.

Abstract

Background: Studies of proliferative lupus nephritis (PLN) suggest that African-Americans have a poorer prognosis than Whites. However, no study has simultaneously examined socio-economic status. We studied rates of progression of PLN among a tri-ethnic population with respect to socio-economic status and race/ethnicity.

Methods: A retrospective cohort study was carried out using individual and census-based neighbourhood data. Consecutive patients in urban tertiary care centres with biopsy-proven PLN were studied. The main outcome was time to doubling of serum creatinine.

Results: Among 128 patients with PLN, the percentage of patients who did not double their serum creatinine at 5 years was 67.0% (+/-4.8%) and at 10 years was 58.9% (+/-5.7%). In bivariate analyses, residence in a poor neighbourhood was positively associated with progression (P = 0.03), as was African-American and Hispanic race/ethnicity (P = 0.01). Residence in a poor neighbourhood remained associated with progression of disease after adjustment for age, sex, creatinine, hypertension, cyclophosphamide treatment and race/ethnicity [relative risk (RR) 3.5, 95% confidence interval (CI) 1.2-11, P = 0.03]. After adjustment for poverty and insurance, the RR for African-American race/ethnicity was reduced from 3.5 to 2.7 and was not statistically associated with progression of disease in the full model (P = 0.10). A similar reduction in RR from 5.5 to 3.6 was seen for Hispanic race/ethnicity, but this retained statistical significance (P = 0.03).

Conclusions: Poverty is an important risk factor for progression of PLN, independent of race/ethnicity. Hispanics have an elevated risk similar to or greater than African-Americans. Given these findings, some of the poorer prognosis of African-American patients with PLN may result from socio-economic rather than biological or genetic factors.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adolescent
  • Adult
  • African Americans / statistics & numerical data*
  • Age Distribution
  • Biopsy, Needle
  • Cohort Studies
  • Confidence Intervals
  • European Continental Ancestry Group / statistics & numerical data*
  • Female
  • Hispanic Americans / statistics & numerical data*
  • Humans
  • Incidence
  • Lupus Nephritis / epidemiology*
  • Lupus Nephritis / pathology
  • Male
  • Middle Aged
  • Probability
  • Prognosis
  • Proportional Hazards Models
  • Retrospective Studies
  • Risk Factors
  • Severity of Illness Index
  • Sex Distribution
  • Socioeconomic Factors
  • Survival Rate
  • United States / epidemiology