Summary

Athlete SARMs abuse is rapidly growing, harmful, and understudied.

Abstract

Introduction

Selective Androgen Receptor Modulators (SARMs) are small-molecule compounds that exert agonist and antagonist effects on androgen receptors in a tissue-specific fashion. SARMs are not FDA approved in the USA, but are readily available for purchase online. Increasingly, athletes have turned to SARMs in recent years as a means of augmenting lean muscle mass, evidenced by positive tests across multiple athletic organizations including the Olympics, NFL, NBA, UFC, and NCAA. However, the safety of SARMs for anabolic effects has not been established, and case reports associate SARMs with deleterious effects, including drug-induced liver injury, myocarditis, and tendon rupture. The purpose of this novel systematic review is to provide a comprehensive synthesis of the SARMs literature for sports medicine clinicians to understand the clinical effects, treatment protocols, prevalence, and potential contamination associated with athlete-consumed SARMs.

Methods

A systematic review of the English-language literature from PubMed, Cochrane, and Embase was performed according to the PRISMA guidelines. Articles relevant to SARMs clinical outcomes, elimination profiles, contamination, safety profiles, prevalence, and doping control were included. Reviews, meta-analyses, editorials, and conference abstracts were excluded. Ostarine (Enobosarm, GTx-024, MK-2886, S-22), Ligandrol (LGD-4033, VK5211), RAD-140 (Testolone, Vosilasarm), and Andarine (S-4, GTx-007) were selected as the primary focus of the systematic review, given the reported widespread recreational abuse of these specific SARM compounds. Data specific to each article type or topic (e.g. clinical study, case report, preclinical model) were extracted, assessed, and presented in tables. The heterogeneity of the study data precluded meta-analyses.

Results

The literature search yielded 2012 abstracts, and a total of 72 articles from 2003 to 2022 were identified for inclusion. Notably, four of eight SARMs clinical studies reported significant increases in lean body mass (LBM). Thirteen case reports described 15 cases of SARMs abuse, all published within the last 3 years. All of the described patients were male, the median age was 32 (range, 19 – 52) years, more than half were identified as athletes (8/15), and all ingested SARMs orally for an average course of 8 weeks. Five patients explicitly denied “illicit drug use.” Athletes most commonly purchased SARMs online, and a majority of these compounds are contaminated with other substances. Athletes consumed SARMs at much higher doses than clinically studied, which may increase the risk of associated side effects such as liver injury, impaired insulin sensitivity, cardiovascular events, and tendon damage (perhaps akin to anabolic androgenic steroids in this regard).

Conclusion

Athlete SARMs abuse is substantial yet unsafe, and public health oversight bodies should advocate for regulation of these gray-market compounds. Further basic science and clinical studies are warranted to validate these early reported findings regarding SARMs. The results of this systematic review serve to educate sports medicine clinicians and researchers on how to better identify, diagnose, and treat athlete SARMs abuse.