Tuesday, March 10, 2009

Income differences no longer contribute to mortality risks for dialysis patients
By Kelly Winget, DCRI Communications

Despite the Centers for Medicare and Medicaid Services creating an end-stage renal disease (ESRD) program that provides health insurance for patients with this specific disease, previous studies have indicated that patients on dialysis who live in lower-income areas faced increased risks of death than those patients in higher-income areas.

A new study, led by DCRI researchers, has found almost no difference in survival rates between patients in lower-, middle-, or higher-income areas. However, the new study found that African-American patients have a lower mortality risk no matter what income area they live in.

The study was led by the DCRI's Eric Eisentein, DBA, and results were published in the February issue of the American Journal of Medicine.

Researchers looked at mortality rates among patients with ESRD in lower-, middle-, and higher-income areas. They used the U.S. Renal Data System to analyze data on more than 186,000 patients who received dialysis at stand-alone clinics between 1996 and 1999. They also compared how race affected mortality by using non-African American patients who lived in middle-income areas as the reference group. ZIP code and Census data provided information about the median income levels where patients lived.

The analysis found that patients in the lower-income areas were typically younger, female, African-American patients. These patients were also more likely to have high blood pressure and often diabetes was the main cause of the ESRD.

After adjusting for other factors, researchers found no difference in mortality risks across income levels. And although African-American patients were typically between five and eight years younger than patients of other races when they started treatment, African-American patients consistently had higher survival rates up to five years following their initial dialysis treatment.

Based on the study findings, researchers believe that Medicare's end-stage renal disease program has helped to eliminate differences in income levels as a risk factor that contributes to mortality for dialysis patients.

Other DCRI researchers involved with the study include Kevin Anstrom, PhD; Judith Stafford, MS; Lynda Szczech, MD, MSce; Lawrence “Doc” Muhlbaier, PhD; and Dan Mark, MD, MPH.

Click here to read the full study (PDF).