Monday, May 31, 2010

Association Between Obesity and Osteoarthritis

Are Obese People at Higher Risk of Developing Osteoarthritis?

Matthew Papa, PhD

In the US and around the world today, obesity is on the rise. This epidemic has scourged countless societies, causing morbidity (incidence of disease) and mortality (disease-related death) rates to multiply. A body mass index (BMI) score of 30 or above establishes the fact that obesity has taken hold of one’s life, linking them to a variety of chronic diseases, musculoskeletal problems, and/or locomotor disability.

Osteoarthritis (OA) is a degenerative joint disease causing pain in the knees, hips, and hands. It involves stiffness, creaking, the locking of joints, and recurring inflammation. The pain usually occurs when the joint is active and becomes increasingly constant as the disease progresses. This is due, in part, to an erosion of articular cartilage, occurring more frequently in the latter stages.

The leading cause of disability in the US, OA affects more than 27 million people. Economically, OA accounts for 25% of primary care visits and at least 50% of all NSAID (Non-Steroidal Anti-Inflammatory Drugs) prescriptions, such as Aleve, Orudis, or Advil. Attacking 70% of people over 65 years of age, it is now considered the most rampant joint disorder across the world. OA does not discriminate however; it predominately assails the obese, aging population.

Dietary and lifestyle changes, accompanied by acupuncture and/or medication can provide temporary relief to chronic symptoms for most OA sufferers. The problem with most OA medications is that they cause mild to severe side effects that can initiate severe reactions or pose serious health concerns to the patient. Among sufferers who find no relief, surgery is an option, with hospitalizations to treat OA sufferers increasing 2.5 times since 1993.

More people are now turning to alternative and natural forms of pain relief, such as the popular Eazol, which are proving to be increasingly effective. The Glucosamine/Chondroitin Arthritis Intervention Trial (GAIT) results have demonstrated significant potential in alleviating OA symptoms in patients who suffer from moderate to severe OA pain. While the numbers are continually increasing, at least 5 million people across the US are supplementing their diets with a product that includes glucosamine or chondroitin sulphate. JointAdvance is a pain relief formula that includes these beneficial substances.

Are Obesity and Arthritis Linked?

In 2001, an Australian population-based survey conducted among 7500 participants revealed that the prevalence of OA is twice as high in the obese population. They were compared to individuals with a BMI in the normal range (18.5-24.9), regardless of their age and/or socioeconomic status. Results from these studies indicate that obesity is somehow linked to OA.

Obesity and Hip/Knee OA

The most current studies examining the association between obesity and OA reveal that there is definitely a positive correlation. Amid 858 participants in a Scottish survey, the incidence of hip and knee pain was twice as high. Another study in the US, involving 5000 respondents revealed that the occurrence of OA doubled for every five unit BMI score increase. Likewise, amongst 830 middle-aged women in the UK, a strong association between obesity and knee OA was also found.

As OA sets in, bone spurs can form, which are the bony protrusions that emerge along deteriorating joints repetitively injured and worn down by arthritis. Most joint replacement therapy candidates are also obese, as compared to healthier individuals of the same age and gender. The trend of obesity and lower limb joint pain continues to increase with one study showing that the risk of developing these bone spurs among overweight women with a BMI in the range of 25 to 29.9 was also twice as high as those in the normal range (BMI 19 to 25).

Obesity and OA - What Are The Risks?

Even though hip OA is not as prevalent as it is in the knee, it is still a tremendous challenge for those who continue to struggle. Studies have shown that the prevalence of obesity at an earlier age is attributing to an increase of hip replacement surgical procedures to remedy the debilitating effects of hip OA.

In Norway, a cohort study of 1.2 million people identified a probability 3.4 times higher of acquiring OA, among the obese, as compared to those within the normal BMI range. Likewise, the USA Nurses study revealed that an increased BMI at 18 years of age induces a five-fold increase in the risk of needing hip replacement surgery at some point in life.

Obesity and OA in Hands

A 23 year longitudinal (longer-term) study has revealed that there is an association between obesity and the development and progression of hand OA. Although the etiology (identifiable source) is unknown, there is much speculation, since hands are not typically weight-bearing joints. Scientists are presently exploring the effect of increased adipose tissue secretions—characteristic of obese people—as a potential contributor in hand OA advancement.

What Comes First: Obesity Or OA?

Researchers today are attempting to discover whether being obese leads to OA, or does having OA lead to obesity. The evidence indicates that there is an association between the two however, several longitudinal studies have thoroughly examined this phenomenon and the etiology question continues to arise.

The results of the longitudinal Framingham Heart Study, one of the most credible-to-date, revealed that those individuals who were heavier throughout their lives, without having initially any symptoms of OA, had an increased probability of developing OA later in their lives. This shows that obesity can be a stand-alone reason for the development of OA.

Conclusion

It is proven that individuals who are overweight or obese have an increased risk of developing arthritis throughout the course of their lifetime. Due to the weight of the load that is carried and the strain that it places upon the human body, knee OA can develop, in addition to that of the hand and hip.

The most effective solution to remedy the occurrence of OA is the adoption of a weight reduction program that addresses physical activity and the eradication of at-risk behaviors (smoking, drugs, alcohol, etc.). Adhering to a multiple behavior lifestyle intervention program can provide lasting, life-changing benefits, while providing relief to OA sufferers and prevent or reducing the incidences of other chronic diseases from taking hold.

About the Author

As a biology research specialist at Washington University in St. Louis, MO, Matthew Papa, PhD, has a unique perspective and regularly shares his insights and analysis of diet and weight loss programs through his blog. With a keen interest in obesity and its relationship to joint diseases, such as OA, he follows the most relevant studies and reports their findings. His website offers a Bistro MD promotion code and a Diet to Go coupon.

References

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3. Ann Rheum Dis. 2006 Apr;65(4):520-4. Epub 2005 Aug 26. Prevalence and risk factors for joint pain among men and women in the West of Scotland Twenty-07 study. Adamson J, Ebrahim S, Dieppe P, Hunt K.
4. Obesity in total hip replacement. Choong PF, Dowsey MM, Liew D. J Bone Joint Surg Br. 2009 Dec;91(12):1642; author reply 1642-3.
5. Risk factors for onset of osteoarthritis of the knee in older adults: a systematic review and meta-analysis. Blagojevic M, Jinks C, Jeffery A, Jordan KP. Osteoarthritis Cartilage. 2010 Jan;18(1):24-33