Endpoint

Estimated glomerular filtration rate

CAT:outcome/egfrreported in mL/min/1.73m2

Method

eGFR from a stated estimating equation. The equation is recorded on the edge, and creatinine-based equations are flagged as such.

The method is part of the endpoint identity. Studies measuring the same quantity by a different method are held as separate endpoints.

Notes

Creatinine-based eGFR inherits the confound described under serum-creatinine: it will fall when creatinine rises, whether or not filtration changed. Cystatin C-based estimates and measured clearance do not. A curator using a creatinine-based equation to support a renal-harm claim is asserting something the measurement cannot carry. DO NOT ADD THE BARE ACRONYM TO THE LABEL OR MEASUREMENT. A meta-analysis reporting "a non-statistically significant differences in GFR" was refused here for sharing no vocabulary, and that refusal is CORRECT rather than a gap to close. Unqualified, the acronym names either an estimate or a measured clearance, and for this compound the two do not merely differ in precision -- they can move in OPPOSITE directions, because creatine raises serum creatinine and therefore lowers a creatinine-based estimate while true filtration is unchanged. Accepting the bare form would let a renal-safety claim into the graph on a measurement whose confound status is unknown, which is precisely the substitution the note above forbids. A paper stating its equation maps here. A paper stating an inulin or iohexol clearance needs a measured-clearance node, which does not exist yet -- one paper is below the minting threshold in the header. Until then such a claim is correctly refused rather than approximated.

Findings

1 finding from 1 compound, strongest first.

creatine — decreases
SuggestiveGrade C, Suggestive. Weak human evidence, or strong evidence in a mismatched population.Finding
“Specifically, there was an increase in serum creatinine (mean difference 12.63 μmol/L, 95% CI 1.14 to 24.12) and decrease in eGFR (−25.79 mL/min/1.73 m2, 95% CI −44.3 to −7.25) in individuals on creatine supplementation compared to placebo.”
Quoted verbatim from Effect of creatine monohydrate on motor function in children with facioscapulohumeral muscular dystrophy: A multicenter, randomized, double-blind placebo-controlled crossover trial..
Study

crossover
Duration

3 months
Dose

creatine monohydrate ~100 mg/kg/day (2.5-10 g daily by weight band) for 12 weeks per crossover period
Population

children aged 5-18 years with facioscapulohumeral muscular dystrophy; safety outcome, not the primary endpoint; eGFR by the modified Schwartz creatinine-based equation
Effect -25.79 mean difference, 95% CI -44.3 to -7.25
Effect of creatine monohydrate on motor function in children with facioscapulohumeral muscular dystrophy: A multicenter, randomized, double-blind placebo-controlled crossover trial.2025PMID:40366059

Notes

Findings

1 finding from 1 compound, strongest first.

creatine — decreases

SuggestiveFinding

“Specifically, there was an increase in serum creatinine (mean difference 12.63 μmol/L, 95% CI 1.14 to 24.12) and decrease in eGFR (−25.79 mL/min/1.73 m2, 95% CI −44.3 to −7.25) in individuals on creatine supplementation compared to placebo.”

Study: crossover
Duration: 3 months
Dose: creatine monohydrate ~100 mg/kg/day (2.5-10 g daily by weight band) for 12 weeks per crossover period
Population: children aged 5-18 years with facioscapulohumeral muscular dystrophy; safety outcome, not the primary endpoint; eGFR by the modified Schwartz creatinine-based equation

Effect -25.79 mean difference, 95% CI -44.3 to -7.25

Effect of creatine monohydrate on motor function in children with facioscapulohumeral muscular dystrophy: A multicenter, randomized, double-blind placebo-controlled crossover trial.2025PMID:40366059