Background: Multiple myeloma (MM) is the most common hematologic malignancy. The disease remains incurable but autologous hematopoietic stem cell transplantation (AHSCT) prolongs life when compared to conventional chemotherapy. Patient- and therapy-related factors influence the morbidity and mortality after AHSCT but the influence of socioeconomic status (SES) on the outcome of patients after this procedure has not been well studied. The Department of Veterans Affairs (DVA) provides medical services to veterans throughout the nation. For decades, the DVA has provided equal access to eligible patients that require AHSCT.

Study Purpose: Since a substantial percentage of veterans come from low socioeconomic strata, we decided to study the influence of total family annual income (TFAI), as a measure of SES, on the outcome of patients with MM after AHSCT.

Methods: We retrospectively analyzed 83 consecutive patients who underwent AHSCT for MM at the Audie L. Murphy Memorial Veterans Hospital in San Antonio, Texas between January 2005 and July 2008. The following patient- and transplant-related characteristics were analyzed: demographic information, TFAI analyzed in $10,000 intervals, time interval between diagnosis and AHSCT, conditioning regimen, pretransplant Karnofsky Performance Status (KPS) score, Transplant Specific Comorbidity Index (TSCI) score and mortality rate after AHSCT. Patients were stratified in two groups based on TFAI below and above $30,000.

Results: Eighty (96%) of the patients were males. The median age at transplantation was 59 years (range 28 – 74). Forty-five (54%) of the patients were Caucasians, 27 (33%) African-Americans and 11 (13%) Hispanics. The median time interval between diagnosis and transplantation was 12 months (range 4–103). The median TFAI was $20,000 – $30,000. Thirty-five patients had TFAI of < $30,000 and 48 patients had TFAI > $30,000. All patients received melphalan as the conditioning regimen before transplantation. The median KPS score was 90 (range 70–100) and the TSCI score was 3 (range 0–12). The median overall survival for all the patients was 17 months (range 0–46). There were no statistically significant differences between the two groups regarding gender, ethnicity, KPS score, TSCI score or time interval between diagnosis and transplant. However, there were statistically significant differences between the groups regarding age and survival. Patients with TFAI < $30,000 were younger than patients with TFAI > $30,000 (p = 0.001). When survival was compared between the two groups, the survival of patients with TFAI < $30,000 was lower at 16 months, (range 0–43) while patients with TFAI > $30,000 had a median survival of 24 months (range 1–46) p = 0.03. When survival posttransplantation was adjusted for age, the influence of TFAI on survival remained statistically significant (p = 0.019) favoring the higher income group. Patients in the low income group had a 6.2 higher risk of mortality when adjusted for age.

Conclusions: Our findings suggest that lower TFAI is associated with poorer outcomes after AHSCT in veterans with MM. The access to AHSCT for both groups was similar based on time interval between diagnosis and transplantation. Additional studies will be necessary to determine if other unidentified socioeconomic differences influence outcome after AHSCT.

Second AACR International Conference on the Science of Cancer Health Disparities— Feb 3–6, 2009; Carefree, AZ

American Association for Cancer Research
2009