The researchers found a much higher incidence of other serious illnesses among MDS patients than among American seniors as a whole. More than 73% of MDS patients experienced a heart attack within three years of diagnosis, while 54.5% of the general Medicare population did. The prevalence of other conditions was also higher, including: diabetes (40% for MDS patients, vs. 33.1% non-MDS); dyspnea, a type of shortness of breath (49.4% vs. 28.5%); liver disease (.8% vs. .2%); and sepsis, a serious blood infection (22.5% vs. 6.1%). MDS patients requiring blood transfusions had a higher incidence of these conditions than those who were not transfused.
Acute myeloid leukemia (AML) developed within three years in 9.6% of newly diagnosed MDS patients, and those who received transfusions progressed to AML at a rate of 24.6% (previous estimates were that 20-30% of MDS patients progressed to AML).
A much higher percentage of MDS patients died during the study period than those without MDS. The three-year survival rate for those with MDS was 60%, while it was 84.7% for the general Medicare population. The mortality rate for transfused MDS patients was higher than for those not transfused. The higher survival rates in this study compared to SEER were attributed to the higher percentage of early stage patients treated in communities compared to hospital-based tumor registries.
While the health consequences and scope of the disease found in the study were alarming, the cost of treating MDS also proved to be significant. In 2003, the median amount billed to Medicare for MDS was $16,181, compared to $1,575 for Medicare beneficiaries as a whole.
"As the U.S. population continues to age, MDS will become a more prominent medical problem with a significant impact on the health care system," says Dr. Goldberg.
Dr. Goldberg believes that this study will provide a baseline for additional research. "Since we now know the scope of the problem as it was before MDS medications became available, it will be interesting to see in future studies how new cancer treatments have impacted the disease. We also need to learn why MDS patients develop other conditions, such as heart failure, so that we can treat the whole person."
Other researchers from the John Theurer Cancer Center, as well as researchers from Novartis Pharmaceuticals and Quorum Consulting, also contributed to this study.
Source: John Theurer Cancer Center