Kidney Week

Abstract: SA-PO532

Antineoplastic Agents Associated with Hypomagnesemia and Effect Modifiers for the Associations

Session Information

• Acid-Base, Calcium, Potassium, and Magnesium Disorders: Clinical
  October 26, 2024 | Location: Exhibit Hall, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Fluid, Electrolytes, and Acid-Base Disorders

• 1102 Fluid, Electrolyte, and Acid-Base Disorders: Clinical

Authors

• Suzuki, Kodai, Nagoya Shiritsu Daigaku Daigakuin Igaku Kenkyuka Igakubu, Nagoya, Aichi, Japan

Kodai Suzuki, MD

• Murashima, Miho, Nagoya Shiritsu Daigaku Daigakuin Igaku Kenkyuka Igakubu, Nagoya, Aichi, Japan

Miho Murashima, MD, PhD

• Miyaguchi, Yuki, Nagoya Shiritsu Daigaku Daigakuin Igaku Kenkyuka Igakubu, Nagoya, Aichi, Japan

Yuki Miyaguchi

• Kasugai, Takahisa, Nagoya Shiritsu Daigaku Daigakuin Igaku Kenkyuka Igakubu, Nagoya, Aichi, Japan

Takahisa Kasugai, MD

• Tomonari, Tatsuya, Nagoya Shiritsu Daigaku Daigakuin Igaku Kenkyuka Igakubu, Nagoya, Aichi, Japan

Tatsuya Tomonari

• Ono, Minamo, Nagoya Shiritsu Daigaku Daigakuin Igaku Kenkyuka Igakubu, Nagoya, Aichi, Japan

Minamo Ono

• Mizuno, Masashi, Nagoya Shiritsu Daigaku Daigakuin Igaku Kenkyuka Igakubu, Nagoya, Aichi, Japan

Masashi Mizuno, MD, PhD

• Hamano, Takayuki, Nagoya Shiritsu Daigaku Daigakuin Igaku Kenkyuka Igakubu, Nagoya, Aichi, Japan

Takayuki Hamano, MD, PhD

Background

Hypomagnesemia (hypoMg) is common and associated with worse outcomes among patients with malignancy. In this study, we aimed toidentify anti-neoplastic agents associated with it and modifiable factors for the associations.

Methods

In this retrospective cohort study, we enrolled patients receiving antineoplastic agents at Nagoya City University Hospital from 2018 to 2020. We employed mixed-effects logistic regression models to identify factors associated with hypoMg (Mg<1.8mg/dL) and effect modifiers for the associations. As a sensitivity analysis, missing data for dipstick proteinuria were multiply imputed and the data were analyzed by Poisson regression with frequency of laboratory measurements as an exposure variable.

Results

A total of 2644 patients were included. The mean age was 63.8 (16.5) years and the mean eGFR was 71.9 (21.1) mL/min/1.73m2. Serum magnesium (Mg) was measured at least once in 1692 (64.0%) patients, of these, 718 (42.4%) developed hypoMg (15.5 events/100 patient-measurements). Cetuximab was most strongly associated with hypoMg (OR 4.36 [3.44-5.54]), followed by platinum drugs (2.20 [1.87-2.59]). Loop diuretics were negatively associated with hypoMg (0.76 [0.61-0.96]), while eGFR was not. Cetuximab was associated with hypoMg among non-users of vitamin D recptor activator (VDRA) (4.36 [3.44-5.54]) and non-users of bisphosphonates (4.70[3.65-6.04]) but not among users of these agents (p for interaction <0.001 and 0.003, respectively). In the sensitivity analyses, the effect modification by VDRA was consistent, while the effect modifications by bisphosphonates were not observed. Proteinuria was not associated with hypoMg and no effect modifications were seen by eGFR or proteinuria.

Conclusion

HypoMg was common among those with malignancy, while only about two-thirds of patients had Mg measurements. Cetuximab was the agent most strongly associated with hypoMg, and cetuximab-induced hypoMg might be prevented by using vitamin D or bisphosphonates.