Infection Poses Lethal Risk Early in Patients With Multiple Myeloma

Many patients with multiple myeloma succumb to infection before they have a chance to benefit from cancer therapy, according to a new study from Sweden.

More than 20% of patients died of infection within a year of myeloma diagnosis. Patients had heightened susceptibility to bacterial and viral pathogens, reported Cecilie Blimark, MD, a consultant hematologist at Sahlgrenska University Hospital, Gothenburg, Sweden, at the 54th Annual Meeting of the American Society of Hematology.

“We found the risk of specific infections, such as pneumonia and septicemia, to be more than 10 times higher in patients [with myeloma] than in controls during the first year after diagnosis of multiple myeloma,” said Blimark.

Infection risk doubled from the 1986-1993 period to the 2000-2004 period, raising questions about the possible contributions of modern myeloma therapy to the risk of infection.
“The increasing risk we observed in later years calls for more studies concerning new strategies regarding infectious complications and their prevention,” said Blimark.

This first study of its kind was a large, population-based investigation of the magnitude of infection risk in patients with myeloma. Infection has long been recognized as a major cause of morbidity and mortality in this patient population, but the extent of the risk had not been previously characterized.

The data came from the Swedish national cancer registry and included 9610 patients who had newly diagnosed multiple myeloma between 1988 and 2004. For each patient, investigators identified 4 individuals without myeloma who were matched for age, sex, and county of residence. The follow-up continued through 2007.

The results showed that 22% of the patients with myeloma died of infection during the first year after diagnosis. In addition, the patients had an infection hazard almost 12 times greater than that of the control group, including hazard ratios (HRs) of 11.0 for bacterial infections and 18.0 for viral infections.

Throughout the entire study, patients with myeloma had an infection HR of 7.1 versus the control group. Overall HR was 7.0 for bacterial infections and 9.0 for viral infections.
The greatest differentials in HRs included those for meningitis (HR, 16.6), septicemia (HR, 15.6), and herpes zoster (HR, 14.8); other significant differences (P <.05) involved bacterial pneumonia (HR, 7.7), viral influenza (HR, 6.1), endocarditis (HR, 5.3), osteomye- litis (HR, 3.5), cellulitis (HR, 3.0), and pyelonephritis (HR, 2.9).

Reference
Blimark C, Mellqvist U-H, Landgren O, et al. Multiple myeloma and infections: a population-based study based on 9,610 multiple myeloma patients. Presented at: 54th American Society of Hematology Annual Meeting; December 8-11, 2012; Atlanta, GA. Abstract 945.