Is Osteoarthritis Part of Metabolic Syndrome?

Osteoarthritis is a fragment of cartilage, a prominent protein that covers the tip of the bone in the joints. Normal cartilage helps with the absorption of shock by acting as a cushion on the tip of the bone. The fluid-like cartilage in the joints allows for smooth joint movement. When osteoarthritis develops, the space between the bones narrows, the cartilage wears and the exposed bone is exposed. This results in painful joint movements as well as limited movement. Bone bones can grow around the joints, limiting further movement and contributing to more pain. Inflammation plays only a minor role in osteoarthritis.

There are many causes of osteoarthritis, the most famous of which is the aging process. As we age, cartilage content increases and protein content decreases. As the water content increases, the cartilage becomes softer, more detailed and loses its mechanical properties. Decreased protein content contributes to the slow degeneration of cartilage, resulting in wrinkles and erosion.

Other causes of osteoarthritis include abnormal bone alignment. In the foot, the most common cause is the wrong foot mechanic. When the legs are not aligned and are not functioning properly, they cause abnormal pressure on the joints in the legs, ankles, knees, hips and back. Trauma is the leading cause of arthritis. Direct trauma may disrupt the structure of the joints, cause joint mal-alignment or cause a weakening of the surrounding structure, resulting in unstable joint osteoarthritis and ultimately. Other causes, such as infections, medications (such as steroids) and genetics contribute to the development of arthritis.

Obesity is a common cause of arthritis. The exact mechanism for how excess weight affects osteoarthritis is unclear. Although the excess burden placed on the joint surface will accelerate cartilage breakdown, obesity is also associated with hand osteoarthritis, which is a more systemic cause. Obesity increases your risk of metabolic syndrome. Metabolic syndrome is a condition characterized by a set of risk factors associated with coronary artery disease, stroke and type 2 diabetes. Risk factors include high blood pressure, abdominal obesity (fat around the waist), abnormal cholesterol levels (such as triglyceride levels) high & low HDL levels) and insulin resistance (which corresponds to high blood sugar). The basic theory of metabolic syndrome is linked to body metabolism, the possibility of insulin resistance. Insulin resistance is the inability of cells to efficiently use insulin, a hormone that transports sugar from the bloodstream to the cell. The result is high blood sugar. Insulin resistance is associated with weight gain and inactivity.

In a recent study in the journal Skeletal Radiology, popliteal artery wall thickness was evaluated in individuals with osteoarthritis. Forty-two patients were diagnosed with osteoarthritis in various joints compared to 27 patients without osteoarthritis (control group). Knee MRI is used to assess the wall thickness of the popliteal artery. The osteoarthritis group had thicker vessel walls than the control group, although researchers made adjustments to gender, weight and age. Because the vessel wall thickness is directly related to hypertension and peripheral and coronary artery disease, the authors suggest that osteoarthritis may be another aspect of metabolic syndrome.

One theory to explain the relationship between osteoarthritis and metabolic syndrome is that it is based on white blood cells, immune cells, increasing in areas where fat accumulates, especially around the abdomen (abdominal obesity). As white blood cells grow, they contribute to a wide range of inflammation in the body, resulting in pro-inflammatory conditions (as indicated by high C-reactive protein levels) and the production of immune chemicals (in particular cytokines) that cause a chain reaction resulting in damage to the cartilage. The combination of insulin resistance and pro-inflammatory conditions can also affect normal cartilage repair.

It is possible that osteoarthritis may be an inevitable outcome for those with metabolic syndrome.

Kornaat PR et al. Positive correlation between increased popliteal artery wall thickness and general osteoarthritis: is OA also part of the metabolic syndrome? Skeletal radiol. 2009 Jul 3.
Rojas-Rodríguez J, et al. The relationship between metabolic syndrome and energy consumption deficit in the pathogenesis of obesity-induced osteoarthritis. Hypothesis Med. 2007; 69 (4): 860-8.
Cicuttini FM, Baker JR, Spector TD: The association of obesity with hand and knee osteoarthritis in women: a twin study. J.Rheumatol. 1996; 23: 1221-1226.
Felson DT: Weight and osteoarthritis. J.Rheumatol. 1995; 43: 7-9.
Armstrong CG, Mow VC. Variations in the Intrinsic Mechanical Properties of Human Articular Cracks with Age, Decrease, and Water Content. JBJS. 1982; 64: 88-94.

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