In recent years, chronic kidney disease (CKD) incidence has doubled among older individuals, owing partly to increasing prevalence of conditions such as diabetes and hypertension that damage the delicate blood vessels of the kidneys (Liu 2010). One in ten American adults is now living with some degree of CKD, and kidney disease is the ninth leading cause of death in the United States (NKUDIC 2012; Arora 2014).
The kidneys are two bean-shaped, fist-sized organs located in the back of the abdominal cavity on both sides of the spine near the base of the ribcage. They represent one of the body’s critical biological filtration systems. The kidneys cleanse the blood and ensure the components of the circulatory milieu stay within the narrow ranges necessary to support normal physiology. Impairment of kidney function can beget potentially grave systemic consequences, so maintaining good kidney health is of the utmost importance if one’s goal is to live a long and healthy life (Al-Awqati 2012; Baynes 2014). Although some causes of kidney damage, such as acute kidney injury, can cause rapid onset of severe symptoms, many people with subclinical CKD are unaware of their condition for years until it becomes symptomatic or is revealed by blood tests. CKD is often not detected until it has reached an advanced stage (NIH 2008; NKF 2013a; NKF 2013b).
One of the biggest threats to kidney health can be found in the medicine cabinets of most Americans, or on the shelves of any pharmacy. Most of us do not think twice about taking non-steroidal anti-inflammatory drugs (NSAIDs) or acetaminophen (Tylenol) for even minor aches and pains. But overuse of these pervasive and seemingly innocuous drugs can cause severe acute kidney injury or lead to progression of chronic kidney disease (Gooch 2007; Downie 1991; Pai 2015; Rahman 2014; Le Vaillant 2013; Ozkaya 2010).
Back in 1985, the National Kidney Foundation recommended that labels of over-the-counter NSAIDs display a warning about their potential to cause kidney damage (NKF 1985), but these drugs are often still considered benign by consumers (Jang 2014; LaCivita 2009; Pai 2015). Today, NSAIDs are among the most common medications inappropriately prescribed to older Americans, and have accounted for over 70 million prescriptions and more than 30 billion over-the-counter purchases (Jang 2014). For many years, Life Extension has sounded the alarm about the risk of kidney damage posed by NSAIDs and acetaminophen (Faloon 2004). Sadly, a study published in late 2014 found that nearly half of patients at high risk for the development of acute kidney injury concurrently used NSAIDs, and that “risk for [chronic kidney disease] and [acute kidney injury] is not routinely assessed among those for whom NSAIDs are prescribed” (Jang 2014).
The good news is that kidney health can easily be monitored with inexpensive blood and urine tests. Even for aging individuals without obvious symptoms of kidney disease, novel blood tests such as cystatin C can help identify subclinical kidney impairment (Lassus 2012; Oh 2014; Arimoto 2005; Shlipak, Mattes 2013).
In this protocol, you will learn about the structure and function of the kidneys and the causes of kidney dysfunction. You will also read about the most common diseases of the kidney and how they are typically treated. In addition, you will discover several simple preventive tests that can be used to detect kidney disease early in its course, and a number of dietary and lifestyle considerations to support optimal kidney health, such as avoiding long-term use of NSAIDs, will be reviewed. Integrative interventions that may support kidney health will be discussed as well. Finally, those reading this protocol should also read the Acetaminophen and NSAID Toxicity protocol, which outlines strategies to avoid the detrimental effects of acetaminophen and NSAIDs, since overuse of these drugs is a major contributor to kidney impairment.