What is known about the health effects of non-steroidal anti-inflammatory drug (NSAID) use in marathon and ultraendurance running: a scoping review.

This systematic scoping review aimed to understand the extent and scope of evidence on the health risks of non-steroidal anti-inflammatory drug (NSAID) use in marathon and ultraendurance running. NSAIDs are commonly consumed by runners to combat pain and inflammation; however, the health risks of consuming these drugs during marathon and ultrarunning events are currently not fully understood. Four databases (Cochrane Library, PubMed, MEDLINE and SPORTDiscus) were searched to identify articles focusing on running events of 26.2 miles or further, and they must have reported on the health risks of NSAID use. There was no restriction on the study design or the date of publication. Thirty studies were ultimately included: 4 randomised controlled trials, 1 cross-sectional study, 11 retrospective reviews, 4 case reports, 1 non-randomised control trial, and 9 prospective observational studies. The literature showed that potential health concerns of NSAID use could be split into five categories: electrolyte balance and hyponatraemia; acute kidney injury (AKI); gastrointestinal disturbances; oxidative stress, inflammation and muscle damage; other medical concerns. None of these sections had clear statistically significant links with NSAID use in ultraendurance running. However, potential links were shown, especially in AKI and electrolyte balance. This review suggests there is very limited evidence to show that NSAIDs have a negative impact on the health of ultrarunning athletes. Indications from a few non-randomised studies of a possible effect on kidney function need exploring with more high-quality research.