When discussing anabolic steroid use and its known side effects, it is not uncommon to see bodybuilders express concern over potential liver injury or other cardiovascular health issues. However, we are now starting to see a much larger contingent of our community suffering from an equally serious, although less frequently recognized side effect in kidney disease/failure. This is a fairly recent phenomenon, which started in earnest about 10-15 years ago. Although there were certainly documented cases of kidney disease/failure prior to this, they were not nearly as prevalent as they are today. Although there are many potential causes of kidney failure, in this article we are going to limit ourselves to those most often attributed to the bodybulding lifestyle.
Unfortunately, there is no single cause associated with kidney failure in bodybulders. Often, it is an accumulative effect brought on by the presence of multiple stressors affecting the body at one time, but before we can pinpoint these causes, we must first understand how anabolic steroids affect the body, as well as possess a basic understanding of how the kidneys work to protect the body from toxins.
The kidneys are two bean-shaped organs which sit below the ribcage; one on each side of the spine. Their primary job is to filter the blood of toxins, which they do at a rate of roughly 120-150 quarts of blood per day. From this, they produce about 1-2 quarts of urine, which is then transported from the kidneys to the bladder for disposal.
The kidneys do not work as single, large filtering mechanism. Rather, each one contains about 1 million tiny filtering units called nephrons, which work to purify the blood at a microscopic level. Each of these nephrons contains a tubule, as well as its own filter (called a glomerulus). Just as the digestive system works in a multi-step process to break down food for absorption, nephrons also work through 2–step process to filter the blood. As blood moves through the glomerulus, it allows fluid and waste products to pass through it, while preventing large molecules, such as blood cells and proteins, from doing so. Afterward, this pre-filtered fluid is then sent through the tubules, which further refines the blood by separating toxins from beneficial substances, such as minerals. Ultimately, everything useful is sent back into circulation, while the final concentrated waste product becomes urine.
Let’s pause there for a second and transfer our attention over to a common side effect associated with AAS use - high blood pressure. Anabolic steroids have been thought to increase blood pressure through a variety of possible mechanisms, but it is their sodium retaining properties which are the primary cause of high blood pressure in most users. When anabolic steroids are administered they inhibit an enzyme known as 11-beta hydroxylase, which leads to the increased production of deoxycorticosterone and the subsequent retention of sodium and water. While AAS can vary substantially in their ability to influence this enzyme, as a general rule, the higher the dose employed, the more this enzyme is inhibited. Therefore, high dose users are more likely to experience elevated blood pressure compared to low-dose users.
High blood pressure is frequently implicated as a risk factor in cardiovascular disease and rightly so, but what about its effect on renal (kidney) function? Unfortunately, high blood pressure is a direct cause of renal stress and a leading contributor in the development of kidney failure. In fact, high blood pressure is the №2 cause of kidney failure in the United States right behind diabetes, being responsible for a full 28+% of documented cases and this number has only continued to grow over the last decade. With high blood pressure being one of the most common side effects associated with AAS use, one might think that it would garner more attention among the drug using community, but sadly, it does not.
When blood pressure is high, blood vessels stretch so that blood can flow more easily. This chronic stretching eventually weakens and scars the blood vessels of the kidneys, damaging them and impairing their ability to work properly. Once damaged, they become inefficient at waste and fluid removal. On top of the resulting toxin build-up, the inability to remove excess fluid can elevate blood pressure even more, resulting in a dangerous cycle.
Although anabolic steroid use alone is a potentially significant contributor to kidney disease/failure, as mentioned above, there are usually multiple causes involved in its development. Another potential risk factor is the use of nephrotoxic agents, such as NSAID’s. With anti-inflammatory drugs like Ibuprofen being routinely implicated in the development of kidney disease/failure and with many bodybuilders regularly using these drugs to treat various aches and pains, this risk factor should not be ignored. For anabolic steroids steroid using bodybuilders, the over-use of NSAID’s may be all it takes to enter stage 1 kidney failure, followed by entrance into the later stages if not addressed. Therefore, nephrotoxic drugs should be used sparingly and only as needed. In cases of chronic pain and inflammation, one should seek speak with their physician regarding alternative treatments.