How the Gut Impacts Joint Health

"If everyone is thinking alike, then somebody isn’t thinking."

- General George S. Patton, Jr.

"Arthritis" is a generic term that describes a destructive, inflammatory, painful joint condition. It affects almost 25% of the United States population. There are numerous types of arthritic conditions including:

• Rheumatoid arthritis (autoimmune)
• Psoriatic arthritis (autoimmune)
• Lupus arthritis (autoimmune)
• Ankylosing spondylitis (autoimmune)
• Hemophilia (genetic)
• Sickle cell anemia (genetic)
• Pigmented villonodular synovitis (tumorigenic)
• Septic arthritis (infectious)
• Crystalline arthritis (metabolic)
• Charcot arthropathy (neuropathic)
• Ochronosis (metabolic/genetic)
• Transient synovitis (post-infectious)
• Primary osteoarthritis

Primary osteoarthritis is by far the most common type of arthritis, impacting an estimated 32.5 million adults in the United States. The economic burden, including direct and indirect costs for primary osteoarthritis, is estimated to be 1 to 2.5% of GDP ($2.33T to $5.83T). Conventional treatment strategies for primary osteoarthritis include oral medication (NSAIDs are recommended as first-line therapy), intra-articular injections, and surgical intervention. Orthopedic surgery is one of the most revenue-generating specialties for a hospital and total joint replacement is a major source of this revenue generation. In another blog post, Why I Chose Functional Medicine, I suggested that there may be a lack of interest in finding alternative solutions if the current system is financially buttressed by conventional treatments. I am not suggesting that the conventional model doesn’t provide benefits to some patients, because I think it does, I have seen it first-hand. However, there is a significant financial interest in maintaining and perpetuating the status quo.

The genesis of osteoarthritis is often regarded as mechanical degeneration of the joint due to the accumulation of micro-traumatic events over a period of time. Obesity has a major impact on the development of osteoarthritis of the lower extremity, and it is thought that increased weight leads to additional mechanical wear of the joint. Although mechanical degeneration is a plausible hypothesis, there is newer evidence (here, here, here, here, here, here, and here) suggesting that the gut microbiome plays a substantial role in the initiation of the necessary inflammatory cascade that contributes to the development of osteoarthritis. It has been observed that a poor diet, high in fat and/or sugar, can cause an imbalance of firmicutes (Gram-positive bacteria) and bacteroidetes (Gram-negative bacteria) phyla in the gut; this can initiate a systemic inflammatory cascade that affects the joints and many other organ systems. Intestinal permeability and gut dysbiosis have an intimate association with the development of arthritis in a very nuanced way. While there is most certainly a mechanical component to osteoarthritis, there seems to be a much more complex pathogenic process.

As mentioned above, non-steroidal anti-inflammatory drugs (NSAIDs) are the first-line therapy for patients dealing with joint pain from osteoarthritis. These medications are effective in managing the pain associated with osteoarthritis but can have significant adverse events. In a 1999 paper from the New England Journal of Medicine, it estimated that there were approximately 103,000 annual hospital admissions from NSAID-related gastrointestinal bleeding and 16,500 deaths. Today, these numbers are likely higher due to increasing numbers of patients with arthritis. Additionally, NSAIDs themselves cause intestinal permeability (here, here, and here) which is a suggested mechanism for the development of osteoarthritis. While NSAIDs are effective in treating pain symptoms associated with osteoarthritis, they may be contributing to the problem that they are attempting to treat.

I often discuss diet and lifestyle modifications in detail with some patients in my clinic. When I tell them that there is a link between their gut health and joint pain, some of them look at me like I have two heads. Google and other internet search engines have been a blessing and a curse to all physicians. Patients have been empowered, having access to extensive, free digital information at their fingertips. A survey conducted by eligibility.com found that 89% of patients Google their symptoms prior to seeing their physician. While the Internet is a powerful resource for patients, it cognitively primes the patient, and they are often only looking for the physician to corroborate their findings. Repudiating their findings with an alternative explanation can lead to distrust and skepticism. Tethering physician compensation to meaningless metrics such as "likelihood to recommend," encourages affirmation of the patient and could potentially prevent physicians to have difficult, but necessary conversations with their patients. The medical system has become a production line fraught with algorithms, standard work, and protocols. Patients are not viewed or treated as individuals. Pharmaceutical treatment strategies are focused on symptomatology and rarely disease pathology. Functional medicine provides an evidence-based alternative approach that addresses the pathology and subsequently, the symptoms resolve.