Effects Of Nsaid Use On Biomarkers Of Kidney Stress Following A Marathon

Abstract

The use of nonsteroidal anti-inflammatory drugs (NSAID) is common practice by participants in marathons and other endurance events. Previous research suggests that renal stress is apparent immediately following marathon completion. However, the potential exacerbating effect of NSAID use during a marathon is not well-understood. PURPOSE: Investigate the effect of NSAID use on biomarkers of renal stress following a marathon. METHODS: Twenty-two volunteer participants (14 males, 8 females; 38 ± 10.2y, 70.7 ± 10.1kg, 171.0 ± 7.7cm) at the Kansas City Marathon were recruited and assigned to either a control (n = 15) or NSAID (n = 7) group based on planned or habitual use. Pre-race NSAID ingestion was self-reported as 9.15 ± 4.62 mg/kg of ibuprofen (n=4) or 3.75 ± 1.73mg/kg naproxen sodium (n=3). Urine samples were collected pre-marathon, post-marathon, and 24-h post-marathon. Samples were stored at -80°C and later analyzed for urinary neutrophil gelatinase lipocalin (uNGAL) and urinary cystatin C (uCyC). A robust two-way mixed ANOVA with trimmed means was utilized to account for potential outliers. When significant interaction or main effects were observed, pairwise comparisons were calculated using robust bootstrapped effect sizes with 95% confidence intervals. RESULTS: Immediately post-marathon, there was a significant increase in uNGAL (Cohen’s dR = 0.47 95%C.I. [0.23,0.85]) but there was no longer a significant elevation by 24-h post-marathon (Cohen's dR = 0.16 95%C.I. [-0.61,3.36]). There were no significant effects detected for Cystatin C. Further, NSAID ingestion did not affect uCyC or uNGAL values. CONCLUSION: Renal stress biomarkers suggest potential kidney tubular injury immediately post-marathon, but potential renal stress was negated by 24-h of recovery. Moderate NSAID ingestion before the marathon did not affect kidney stress biomarkers.