Risk Factors for Multiple Myeloma

The risk factors for multiple myeloma are not conclusive, because the cause of multiple myeloma is not known. Researchers believe that multiple myeloma is most likely the result of many risk factors acting together. There are, however, some factors that may be associated with an increased risk of developing multiple myeloma. These multiple myeloma risk factors include genetic factors, prevalence of MGUS, occupational exposure, age, race, and gender.

Some multiple myeloma research has suggested that myeloma may be associated with a decline in the immune system, specific occupations, exposure to certain chemicals, and exposure to radiation. For example, the likelihood of multiple myeloma is higher than average among people in agricultural occupations, petroleum workers, workers in leather industries, and cosmetologists. Exposure to herbicides, insecticides, petroleum products, heavy metals, plastics, and various dusts including asbestos also appear to be risk factors for the disease. However, none of these associations are strong, and in most cases, multiple myeloma develops in individuals who have no known risk factors.

The most significant risk factor for multiple myeloma is age, as 96% of cases are diagnosed in people older than 45 years, and more than 63% are diagnosed in people older than 65 years. Thus, it is thought that susceptibility to multiple myeloma may increase with the aging process.

Research has also shown that genetic factors may be linked to multiple myeloma. These multiple myeloma genetic factors consist of abnormalities in the number or structure of chromosomes. In addition, recent advances in technology and the mapping of the human genome have enabled scientists to discover that abnormalities in the expression, or levels, of some specific genes are associated with the risk for early relapse of multiple myeloma. Both types of genetic abnormalities may help doctors predict the outcome of treatment.