Is Severe Obesity Associated With Increased Risk For Fractures?Friday, September 5, 2014
According to conventional wisdom, one (of the few) health benefits of obesity is stronger bones.
However, according to a study by Sarah Cawsey and colleagues (me included) from the University of Alberta, published in Osteoporosis International, these “stronger” bones may not be quite strong enough to prevent spontaneous and traumatic fractures.
Our study examined the relationship between fracture history and bone mineral density (BMD measured by DEXA) in 400 women with a mean age of 44 yrs and a mean BMI of 46.
Twenty two percent of women (n=87) reported a total of 178 fractures. Of particular note, fragility-type fractures (hip, vertebra, proximal humerus, distal forearm, and ankle/lower leg) were present in 58 (14.5%) of the women.
There was a markedly higher proportion of fractures in women in the lowest femoral neck BMD quintile who had any fracture history (41.3 vs. 17.2%), any fragility-type fractures (26.7 vs. 11.7%), hand and foot fractures (16.0 vs. 5.5%), other fracture types (5.3 vs. 1.2 %), and osteoporotic fractures (8.0 vs. 1.2%) compared to the remaining population.
No clinical or biochemical predictors of fracture risk were identified apart from BMD.
Our finding show that severely obese women with the lowest BMD values, despite these being close to what would be considered “normal” in a non-obese woman, are at a significantly elevated risk of all types of fractures compared to severely obese women with elevated BMD.
Given the substantial fracture risk seen in our study, it may well be worth considering evaluating the potential benefits of routine BMD assessments in pre-menopausal women with severe obesity.
Cawsey S, Padwal R, Sharma AM, Wang X, Li S, & Siminoski K (2014). Women with severe obesity and relatively low bone mineral density have increased fracture risk. Osteoporosis international : a journal established as result of cooperation between the European Foundation for Osteoporosis and the National Osteoporosis Foundation of the USA PMID: 25182230.
Friday, September 5, 2014
I once read an article (cannot cite) where ideal BMIs were given to avoid various medical complications. If you wanted to avoid diabetes, the ideal BMI was 22. If you wanted to avoid bone fractures, the BMI was 29. If you wanted to avoid death within the next ten years, it was 27.6. Too bad we cannot arbitrarily pick our BMIs dependent on what traumas we wish to avoid. If you want to avoid stigma and discrimination, you certainly wouldn’t pick a 46.
Friday, September 5, 2014
“No clinical or biochemical predictors of fracture risk were identified apart from BMD.”
Did you look at dieting history?
I broke several bones in my life (8 total, I believe), and all fractures happened while I was weight reduced. My bone density improved since I regained the weight I had lost, but I suspect that my dieting history will leave me more prone to fractures for the rest of my life.