In The News: October 2012
Moderate Alcohol Consumption May Help Prevent Bone Loss
Drinking a moderate amount of alcohol may benefit a woman’s bone health, lowering her risk of developing osteoporosis. Researchers at Oregon State University studied 40 early postmenopausal women who regularly consumed one or two drinks a day, were on no hormone replacement therapy, and had no history of osteoporosis-related fractures. They found evidence of increased bone turnover—which leads to a thinning of the bone structure, a risk factor for osteoporotic fractures—during the two-week period when the participants stopped drinking. Even more surprising, they found that less than a day after the women resumed their normal drinking, their bone turnover rates returned to previous levels. The study’s authors concluded that “drinking moderately as part of a healthy lifestyle that includes a good diet and exercise may be beneficial for bone health, especially in postmenopausal women.”
Higher Doses of Vitamin D Found to Reduce Fracture Risk in Older Adults
Based on the results of 11 trials examining vitamin D and fracture risk in more than 31,000 older adults, investigators at Tufts University found higher doses of vitamin D most beneficial in reducing bone fractures. Subjects were divided into quartiles ranging from zero to 2,000 International Units (IU) of daily vitamin D intake. In the top quartile, there was a 30 percent reduction in hip fracture risk and a 14 percent reduced risk of fracturing other bones. Researchers found that taking between 800 IU and 2,000 IU significantly reduced the risk of most fractures in both men and women age 65 and older. Importantly, they found there was no benefit to taking vitamin D in doses below 800 IU per day for fracture prevention. The current Dietary Reference Intake for vitamin D in older adults set by the Institute of Medicine is a minimum of 600 IU per day for adults between 51 and 70 and 800 IU for adults over 70.
Smoking Associated with Hip and Knee Replacement Failure
While it is well known that tobacco and nicotine use diminish the body’s ability to heal, two new studies have taken it a bit further by examining the effects of smoking on total joint replacment. The first study, which examined smoking’s impact on total knee replacement (TKR), found a 10-fold higher revision rate compared to non-smokers. The study involved 621 TKR patients, including 131 smokers. The smoking group had 13 TKR failures (10 percent) compared to five in the non-smoking group (1 percent). The medical complication rate (involving blood clots, anemia, cardiac problems, or acute renal failure) also was significantly higher in the smoking group. The second study looked at the effects of smoking on patients who underwent reconstruction of the acetabulum, the cup-shaped cavity at the base of the hip bone. Between 1999 and 2009, 533 hip replacements, including 159 primary and 374 revsion surgeries, were examined. The failure rate in smokers was 9.1 percent, compared to 4.3 percent in non-smokers. Investigators recommended that surgeons stress smoking cessation before surgery to ensure optimal recovery and outcome.
Study Suggests Changes in Rotator Cuff Surgery Rehab Needed
A new study suggests that current rehabilitation procedures used for a rotator cuff repair may be partially to blame for the high rate of healing failures. The study, conducted by New York City’s Hospital for Special Surgery and using a rat model, suggests that immobilizing the shoulder for four to six weeks after surgery, rather than quickly starting physical therapy, improves healing. Studies have shown that 20-40 percent of patients undergoing rotator cuff surgery have failed healing. Rehabilitation after surgery typically consists of immobilizing the shoulder in a sling for seven to 10 days, physical therapy with passive and assisted motion for six weeks, followed by physical therapy with active motion for six weeks. Researchers found that rats with their joint immobilized experienced the best healing. They also could withstand higher loads before failure and had better bone density. Investigators suggest that the best path to recovery might be to keep individuals in slings for six weeks and then start with passive motion therapy.