Dynamic Magnesium Replacement Strategies and 28-Day Mortality in Non-Cardiac Critically Ill Patients With Hypomagnesemia: A Target Trial Emulation

Fujian Provincial Hospital

Status: Completed

Conditions: Hypomagnesemia

Study type: Observational

Funder types: Other

Identifiers

NCT07380542

HChen-MgReple2025

Details and patient eligibility

About

This study looks at how different ways of giving magnesium (a nutrient) affect the risk of death within 28 days for adults with low magnesium levels who are in the intensive care unit (ICU) for non-heart-related reasons. We will use data from past ICU patients (2008-2019) to compare three approaches:

No magnesium treatment (even if levels are low); Daily magnesium treatment (regardless of daily levels); Dynamic treatment (only giving magnesium when daily tests show low levels). The goal is to find out which strategy is safest and most effective for this group of patients.

Full description

This is a target trial emulation (a type of observational study that mimics a clinical trial) using data from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database (2008-2019).

Inclusion criteria: Adults (≥18 years) admitted to the ICU, with serum magnesium <1.7 mg/dL within 72 hours of admission, and no history of heart disease or cardiac surgery.

Sample size: 12,887 patients. Interventions (simulated): Three magnesium replacement strategies (Never Treat, Always Treat, Dynamic Treat).

Outcome: 28-day all-cause mortality (death from any cause). Analysis methods: We will use the G-formula (to handle time-varying factors that could affect results) and sensitivity analyses to check if findings are reliable.

Enrollment: 12,887 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

1. Age ≥ 18 years.
2. Admitted to the Intensive Care Unit (ICU).
3. Developed hypomagnesemia (Serum Magnesium < 1.7 mg/dL) within the first 72 hours of ICU admission.

Exclusion criteria

1. Admitted due to cardiac or cardiosurgical causes (e.g., Cardiac Surgery Recovery Unit, CCU, CVICU).
2. Underwent cardiac surgery during hospitalization (identified by ICD-9/10 procedure codes).
3. Primary discharge diagnosis of major cardiac conditions (e.g., myocardial infarction, heart failure, arrhythmias).

Trial design

12,887 participants in 3 patient groups

Never Treat Group

Description:

Patients with hypomagnesemia who received no magnesium replacement therapy during their ICU stay, regardless of daily serum magnesium levels

Always Treat Group

Description:

Patients with hypomagnesemia who received daily magnesium replacement therapy during their ICU stay, regardless of daily serum magnesium levels

Dynamic Treat Group

Description:

Patients with hypomagnesemia who received magnesium replacement therapy only on days when their daily serum magnesium level was \<1.7 mg/dL during their ICU stay