Incidence and Burden of the Myelodysplastic Syndromes | Aplastic Anemia and MDS International Foundation

Incidence and Burden of the Myelodysplastic Syndromes

PubMed Abstract: 
Original Publication Date: 
Wednesday, October 14, 2015

The incidence of myelodysplastic syndromes (MDS) has been underestimated in population based registries due to lack of reporting and under-diagnosis.  Using Medicare databases, the incidence in patients 65 years or older is estimated to be between 75 and 162 per 100,000 and growing.  There are several unmet needs in this patient population, including patients not receiving therapies to potentially reduce transfusion needs and lack of treatment options for patients who fail standard therapy.  In addition, older MDS patients are not always given the opportunity to participate in shared decision making for their healthcare needs.

Key-Findings:

-MDS is a disorder of the bone marrow where cells are not maturing properly resulting in low blood counts, increasing the risk of infection, bleeding, and fatigue.  It is more common in older patients, often in their 70s and 80s. 

-The incidence of MDS is underreported in population based registries due to a variety of reasons, including under-diagnosis, lack of uniform classification as a malignancy, lack of reporting in outpatient clinics, and changing of guidelines for how MDS is coded when billing insurance companies.

-It is estimated that the prevalence of MDS in the United States is somewhere between 60,000 to 170,000 and projected to rise as newer therapies are developed and people live longer.

-Going forward, it may be useful to create new search engines that could link electronic pathology reports to cancer registries and increase accuracy of data.

-Accurate diagnosis of MDS is important to estimate health care resource utilization.  Cost of drugs alone for lower-risk patients is estimated to be $63,577 per patient per year.  Certain characteristics are associated with increased cost, including shortness of breath, sepsis, arrhythmia, bacteremia, transfusion dependency, congestive heart failure/heart disease, and pneumonia.  Patients requiring transfusions also have higher Medicare costs and require more hospital services. 

-Red-blood cell transfusion dependence is associated with increased mortality and worse quality of life in patients with MDS.  Frequent transfusions can result in iron overload, which can increase risk of heart problems, diabetes, breathing difficulties, liver disease, and infections.  Patients who receive active therapies but no transfusions have less risk of these complications than those who are transfusion-dependent. 

-Many patients receiving transfusions do not receive active therapies even though treatments such as azacitidine and lenalidomide have been shown to decrease red blood cell transfusion dependence.  Low-intensity therapy has been shown to be well-tolerated and effective in the older patient population, including those aged 75 and above.  It is unclear why these patients are not receiving active therapies, whether due to patient preference, physicians not offering treatment, or concerns about side-effects since treatment may initially worsen blood counts.  This deserves further investigation.

-Patients who do not respond to or relapse after therapy with hypomethlating agents (azacitidine and decitabine) carry a poor prognosis.  These patients may be considered for a clinical trial or allogeneic stem cell transplant if available.  This is a large unmet need in MDS.  Importantly, many patients do not receive an adequate number of cycles of hypomethylating therapy before being declared a non-responder. 

Conclusions:

-Population-based registries have underestimated the incidence of MDS.  In addition, older patients with low blood counts are often under-diagnosed or not referred to a hematologist.  As we gain access to better epidemiologic data, we may have better tools to address unmet needs in this patient population.

Reviewer Bio: