Low magnesium levels hurt survival in DLBCL after stem cell transplant

In patients with diffuse large B cell lymphoma (DLBCL), hypomagnesemia is associated with worse outcomes after autologous haematopoietic stem cell transplant (AHSCT), a recent study has found.

Researchers retrospectively assessed 581 DLBCL patients eligible for AHSCT. Overall, 82 patients (14.1 percent) had serum magnesium levels below the laboratory limit of 1.7 mg/dL and were identified to have hypomagnesemia. The primary outcome was overall survival (OS), and event-free survival (EFS) was the secondary outcome.

The median magnesium level among those with hypomagnesemia was 1.6 mg/L, as opposed to 1.9 mg/dL in the remaining patients. Over a median follow-up of 3.0 years after transplantation, 45 patients had a relapse, retransplantation, or death event within 100 days, yielding an EFS rate of 7.8 percent. By day 365, the corresponding EFS rate was 26.3 percent.

The median EFS among patients with hypomagnesemia was 3.9 years, nearly half the 6.9-year EFS in those with magnesium levels within the reference range. Day-100 EFS rates were calculated to be 86.4 percent in the former group vs 93.1 percent in the latter; 1-year EFS rates were 62.8 percent and 74.6 percent, respectively.

In terms of OS, 28 overall deaths were reported in the first 100 days after transplantation, while 113 deaths occurred over 1 year. Median OS was 7.3 years in those with hypomagnesemia vs 9.7 years in patients with levels within the reference range.

OR rates at 100 days were 90.1 percent and 96.0 percent in participants with vs without hypomagnesemia, respectively. At 1 year, the corresponding rates were 69.0 percent and 81.7 percent.