The prognostic impact of renal function decline during hospitalization for myocardial infarction.

Aim: We analyzed the mortality risk of myocardial infarction (MI) patients according to renal function, observed during hospitalization. Materials & methods: Patients hospitalized for MI between 2006 and 2018 were followed (n = 5659). We divided the sample into four groups by estimated glomerular filtration (eGFR) [ml/min]: normal functions (lowest eGFR during hospitalization >60); transiently moderate insufficiency (lowest eGFR >30 and ≤60, highest >60); permanently moderate insufficiency (highest eGFR >30 and ≤60); severe insufficiency (highest and lowest eGFR ≤30). Results: Permanently moderate renal insufficiency indicates increased 5-years all-cause mortality (hazard risk ratio: 2.27 [95% CIs: 1.87-2.75], p < 0.0001), but a similar risk was found in patients with the only transient decline of renal functions (hazard risk ratio: 2.08 [95% CIs: 1.70-2.55], p < 0.0001). Both moderate insufficiency subgroups (transient/permanent) did not statistically differ regarding mortality risk. Conclusion: Even just fluctuation of eGFR toward moderate insufficiency during hospitalization represents an important prognostic indicator in MI patients.