Stiffness, Swelling and the Sticky Issue of Sugary Soda

knee osteoarthritisThose of us of a certain age, probably know all about osteoarthritis, the “wear and tear” disease in which joint cartilage is lost. Losing cartilage from your knee is similar to having the shock absorbers go on your car.  It leads to pain, stiffness and other symptoms.

According to a large 2007 study, nearly 20% of women and 15% of men over the age of 45 have  symptoms of knee osteoarthritis.

Until now, many experts thought disease progression was inevitable. I’m pretty sure that’s what my knee surgeon thinks. One such clue: he always says “when I see you again” rather than “if I see you again” at the end of every visit.

Bloomberg Moves To Ban Sugary Drinks In NYC Restaurants And Movie TheatersNow, for men at least, this may be about to change. A new study of more than 2,000 with osteoarthritis of the knee showed that disease progression in men is linked to consumption of sugary soda.

Researchers reviewed the records of 2,149 men and women with confirmed osteoarthritis of the knee.

All filled out dietary questionnaires that asked how many soft drinks, not including sugar-free beverages, they drank on average each week.

Every year for four years, the researchers tracked their osteoarthritis progression by measuring the space between the joints. The more cartilage that is lost, the less the space. Body Mass Index (BMI) was also measured.

After taking into account BMI and other risk factors, men who drank five or more soft drinks a week had twice as much narrowing of joint space compared with men who did not drink sugary soda.

man drinking sodaOur main finding is that the more sugary soda men drink, the greater the risk that knee osteoarthritis will get worse,” says researcher Bing Lu, MD, DrPh. Lu is assistant professor of medicine at Harvard Medical School and associate biostatistician at Brigham and Women’s Hospital in Boston.

If you’re thinking something along the lines of ‘Duh! Tell me something new. Soda=calories=weight gain= risk factor for osteoarthritis, think again.

Much to the researchers’ surprise, the link between knee osteoarthritis progression and sugary soft drinks could not solely be explained by weight.  When the men were divided into obese and non-obese, the link between sugary drinks and worse knee damage held true only in the non-obese men, suggesting that soft drinks worsen knee osteoarthritis independently of the wear and tear on the joints caused by carrying around excess weight.

So what’s a man who enjoys soda to do?  According to Lu the answer is simple. “just don’t drink it!”

Causes-and-Symptoms-of-OsteoarthritisAnother expert says that’s going too far. “As with everything, enjoy soda in moderation. If you are a man with knee osteoarthritis and are drinking a lot of soda, this might be a reason to curb back,” says American College of Rheumatology spokesman Scott Zashin, MD.

He argues that the study doesn’t prove cause and effect and needs to be repeated before any recommendations to patients can be made, he says.

Furthermore he advises, that in patients with osteoarthritis of the knee, every excess pound of weight is 4 extra pounds of dead weight on the knee joint.

And it’s not only Zashin who’s speaking out. The American Beverage Association (ABA), has also taken issue with the findings.

In a statement, the ABA writes: “The authors’ ‘novel  findings’ – as they call them – suggest only a possible association of soft drink consumption with osteoarthritis in knees, which they state cannot be proven without further testing. Consequently, this presentation fails to establish that drinking soft drinks causes any negative health outcomes or even that they are linked to negative health outcomes.”

Lu however is defending his work. He claims that certain ingredients in soda, including phosphoric acid, caffeine, as well as coloring and sweetening agents may affect absorption of calcium and overall bone health.

He even has an explanation as to why the link between soda and disease progression could not be established in women. “It could be due to sex hormones. For example, estrogen has been associated with cartilage degeneration. Further research is needed to understand the pathways.”

Although the jury is still out on this issue, it seems cutting back, or cutting out soda may not be a bad idea.

Could or would you give up your cola?  Let us know!

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On Your Knees!

Regular readers of SRxA’s Word on Health have heard from time to time about my knee problems. For those of you just joining us, it’s a long sorry tale of injuries that originated during my Olga Korbut wannabe days as a pre-teen gymnast, that were exacerbated by years of marathon running and more recently resulted in surgery following a dog-induced injury!

As I write, I’m recovering from having just had my knee drained and preparing to undergo a series of rooster comb injections to alleviate the pain and swelling of the latest flare-up.

Naturally then, I was interested to hear about a new US – Canadian study which intends to explore whether the nagging knee pain and inflammation experienced by women is different from what men encounter and whether biological differences between men and women affect the incidence and severity of knee osteoarthritis.

Mary I. O’Connor, M.D., chair of the Department of Orthopedic Surgery at Mayo Clinic’s campus in Florida, will be the study’s principal investigator.

Osteoarthritis, characterized by the breakdown of cartilage in the joint resulting in stiffness and pain, is the most common form of arthritis. It affects approximately 27 million Americans and is more common in women than men.

According to Dr. O’Connor, “Knee osteoarthritis is a leading cause of disability in the U.S. and women have greater pain and reductions in function and quality of life from this condition than do men.”

While the underlying mechanisms for differences in knee osteoarthritis between men and women are not yet known, recent studies have indicated sex differences at the cellular and molecular levels may influence development of the disease. This study will examine a variety of human tissues normally discarded during total knee replacement surgery performed for severe osteoarthritis. The tissues will be analyzed for possible differences in pain fibers and hormone and vitamin D receptors between female and male patients.

The team hopes that the results will provide valuable clues for more effective treatment and possible prevention. Hopefully this will benefit not only yours truly, but also the multitudes of women who suffer from the constant pain and inflammation of osteoarthritis of the knee.

Truth Test for Knees?

Orthopedic surgeons have identified a molecular biomarker that could potentially help people with knee injuries save time, and money and the risks of surgery.

According to a study just published in The Journal of Bone and Joint Surgery researchers from California, Florida, Pennsylvania and New York have identified a biomarker found exclusively in patients with  torn cartilage.  Potentially, this simple test could help patients avoid the time and cost of undergoing an MRI and identify those who are candidates for surgery rather than those who have less operable conditions.

By analyzing the synovial fluid surrounding the knee joints of 30 patients with meniscal tears, researchers found a protein complex called fibronectin-aggrecan that wasn’t present in 10 volunteers with normal, pain-free knees.  To date, fibronectin-aggrecan has not been found in patients with osteoarthritis.

An estimated 700,000 arthroscopic knee operations are performed each year in the U.S. based on the results of MRI scans, which can cost in the region of $2,500.

While surgeons can use MRIs to try to discern the root of a patient’s knee pain, MRIs often cannot differentiate between inflammations from natural degeneration and a full-fledged tear.

Traumatic and degenerative injuries look the same on MRI,” said Gaetano Scuderi, Professor of  orthopaedic surgery at Stanford School of Medicine. “In a 50-year-old, we can’t tell the difference.”

However, correctly identifying a cartilage tear is only one obstacle. Sometimes, patients sustain pain  after corrective surgery because the tear is not actually the root of pain.

Sometimes you would think you did a great job but the patient still had pain,” Scuderi said. “Why did this  person not get better when another person did?”

Previous studies have shown that surgery is only effective for a torn meniscus or cartilage. Knee pain caused by age-related osteoarthritis or injured hip ligaments can resemble a torn meniscus but isn’t helped by surgery. This distinction isn’t always clear on MRI scans.

In a clinical setting, this new biomarker could effectively differentiate knees with pain-inducing cartilage tears that are responsive to surgery from knees with only natural cartilage degradation.

This would be especially beneficial to older patient populations in whom MRIs always show degeneration. The biomarker test offers a cheaper and more specific identification of pathology. Better still, the researchers are hoping to image the molecule non-invasively as opposed to aspirating it for assay.