Although great efforts have been made in myeloma research, to date no cause for this disease has been identified. However, possible associations have been found between myeloma and several other factors:

• Age – more than half of cases arise in people over age 71
• Male gender – men are 50 percent more likely to develop myeloma than women
• Black heritage
• Family history – while most patients have no affected relatives, those with an affected sibling or parent are four times as likely to develop the disease compared to the general population
• Occupational exposure to certain chemicals, particularly petrochemicals
• Radiation exposure
• Obesity – a study conducted by the American Cancer Society found that being obese increases the risk of developing multiple myeloma
• Other plasma cell diseases such as solitary plasmacytomas and monoclonal gammopathy of undetermined significance