ASBMR Annual Meeting 2011

SAN DIEGO – The risk of hip fracture nearly doubles during the week following a new prescription for a loop diuretic.

In contrast, there is no spike in the risk of hip fracture in the 7 days following a new prescription for other classes of diuretics or for ACE inhibitors, according to an analysis of the massive The Health Improvement Network (THIN) database involving more than 400 U.K. primary care practices.

The most likely explanation for the short-term jump in risk of hip fracture may be related to the prominent urinary symptoms that often accompany a new prescription for loop diuretics. The resultant rush to the bathroom could lead to an increased rate of falls during that initial adjustment period, Dr. Sarah D. Berry speculated at the annual meeting of the American Society for Bone and Mineral Research.

She reported on 28,703 subjects who experienced an incident hip fracture and more than 2 million others who did not during 15.1 million person-years of follow-up recorded in the THIN primary care database. In a nested, case-crossover study, she and her coworkers compared the occurrence of new diuretic prescriptions in the 7 days prior to the hip fracture to the occurrence of new diuretic prescriptions during the control period 31-37 days before the fracture.

The adjusted odds ratio of an incident hip fracture was significantly increased by 80% during the 7 days following a new prescription for a loop diuretic. That being said, it needs to be emphasized that the absolute risk during this week-long window of increased vulnerability remained low: 2.9 hip fractures per 100,000 new loop diuretic prescriptions, according to Dr. Berry of the Hebrew SeniorLife Institute for Aging Research and Beth Israel Deaconess Medical Center, Boston.

Counseling vulnerable older adults and their caregivers about the need for increased awareness and careful ambulation to the bathroom during the 7 days after going on a loop diuretic might help reduce hip fractures, she added.

Dr. Berry declared having no financial conflicts regarding the study, which was supported by the U.S. National Institutes of Health and Hebrew SeniorLife.

SAN DIEGO – The risk of hip fracture nearly doubles during the week following a new prescription for a loop diuretic.

In contrast, there is no spike in the risk of hip fracture in the 7 days following a new prescription for other classes of diuretics or for ACE inhibitors, according to an analysis of the massive The Health Improvement Network (THIN) database involving more than 400 U.K. primary care practices.

The most likely explanation for the short-term jump in risk of hip fracture may be related to the prominent urinary symptoms that often accompany a new prescription for loop diuretics. The resultant rush to the bathroom could lead to an increased rate of falls during that initial adjustment period, Dr. Sarah D. Berry speculated at the annual meeting of the American Society for Bone and Mineral Research.

She reported on 28,703 subjects who experienced an incident hip fracture and more than 2 million others who did not during 15.1 million person-years of follow-up recorded in the THIN primary care database. In a nested, case-crossover study, she and her coworkers compared the occurrence of new diuretic prescriptions in the 7 days prior to the hip fracture to the occurrence of new diuretic prescriptions during the control period 31-37 days before the fracture.

The adjusted odds ratio of an incident hip fracture was significantly increased by 80% during the 7 days following a new prescription for a loop diuretic. That being said, it needs to be emphasized that the absolute risk during this week-long window of increased vulnerability remained low: 2.9 hip fractures per 100,000 new loop diuretic prescriptions, according to Dr. Berry of the Hebrew SeniorLife Institute for Aging Research and Beth Israel Deaconess Medical Center, Boston.

Counseling vulnerable older adults and their caregivers about the need for increased awareness and careful ambulation to the bathroom during the 7 days after going on a loop diuretic might help reduce hip fractures, she added.

Dr. Berry declared having no financial conflicts regarding the study, which was supported by the U.S. National Institutes of Health and Hebrew SeniorLife.

SAN DIEGO – The risk of hip fracture nearly doubles during the week following a new prescription for a loop diuretic.

In contrast, there is no spike in the risk of hip fracture in the 7 days following a new prescription for other classes of diuretics or for ACE inhibitors, according to an analysis of the massive The Health Improvement Network (THIN) database involving more than 400 U.K. primary care practices.

The most likely explanation for the short-term jump in risk of hip fracture may be related to the prominent urinary symptoms that often accompany a new prescription for loop diuretics. The resultant rush to the bathroom could lead to an increased rate of falls during that initial adjustment period, Dr. Sarah D. Berry speculated at the annual meeting of the American Society for Bone and Mineral Research.

She reported on 28,703 subjects who experienced an incident hip fracture and more than 2 million others who did not during 15.1 million person-years of follow-up recorded in the THIN primary care database. In a nested, case-crossover study, she and her coworkers compared the occurrence of new diuretic prescriptions in the 7 days prior to the hip fracture to the occurrence of new diuretic prescriptions during the control period 31-37 days before the fracture.

The adjusted odds ratio of an incident hip fracture was significantly increased by 80% during the 7 days following a new prescription for a loop diuretic. That being said, it needs to be emphasized that the absolute risk during this week-long window of increased vulnerability remained low: 2.9 hip fractures per 100,000 new loop diuretic prescriptions, according to Dr. Berry of the Hebrew SeniorLife Institute for Aging Research and Beth Israel Deaconess Medical Center, Boston.

Counseling vulnerable older adults and their caregivers about the need for increased awareness and careful ambulation to the bathroom during the 7 days after going on a loop diuretic might help reduce hip fractures, she added.

Dr. Berry declared having no financial conflicts regarding the study, which was supported by the U.S. National Institutes of Health and Hebrew SeniorLife.

DENVER – Once-yearly intravenous zoledronic acid in men with osteoporosis reduced their risk of vertebral fractures by 67% over 2 years, compared with placebo, in a large, multinational, phase III, randomized clinical trial.

"This is the first clear demonstration of antifracture efficacy for an osteoporosis agent in male osteoporosis," said Dr. Steven Boonen in presenting the study results at the annual meeting of the American Society for Bone and Mineral Research.

"These findings suggest the use of zoledronic acid as a treatment option in male patients, particularly because annual infusions ensure that patients will have the full effect of treatment for at least the next year," added Dr. Boonen, professor of geriatric medicine and head of the gerontology and geriatrics section at Catholic University of Leuven (Belgium).

He reported on 1,199 men (mean age, 66 years) with primary osteoporosis or osteoporosis secondary to hypogonadism who were randomized in a double-blind fashion to a once-yearly 15-minute infusion of 5 mg of zoledronic acid (Reclast) or placebo at 134 centers. At enrollment, 32% of the men had one or more vertebral fractures.

The primary study end point was the proportion of subjects with one or more new vertebral fractures during 2 years of follow-up. The rate was 1.6% in men assigned to zoledronic acid and 4.9% in placebo-treated controls, which translated to a highly significant 67% relative risk reduction. The 12-month rate was 0.9% in the zoledronic acid group vs. 2.8% in controls, for a 68% relative risk reduction.

The incidence of moderate to severe vertebral fractures was similarly reduced by 63% in zoledronic acid recipients, compared with controls.

Men on zoledronic acid had a stable 60% reduction in levels of the bone turnover biomarker CTx, compared with the placebo group, throughout the study.

At 2 years, bone mineral density was roughly 6% greater at the spine and 2% greater at the total hip in the zoledronic acid group, compared with controls.

"All of these findings are remarkably similar in magnitude to the risk reductions that have been documented with zoledronic acid in the pivotal fracture trial in postmenopausal osteoporosis," the geriatrician observed.

Men on zoledronic acid also experienced a smaller height loss, compared with controls (mean, 2.34 vs. 4.49 mm).

No major safety issues arose in the study. Similar numbers of patients in both study arms dropped out of the trial because of adverse events.

At present, zoledronic acid’s approved indications include treatment to increase bone mass in men with osteoporosis.

Dr. Boonen disclosed that he has received research grants from and serves as a consultant to Novartis.

DENVER – Once-yearly intravenous zoledronic acid in men with osteoporosis reduced their risk of vertebral fractures by 67% over 2 years, compared with placebo, in a large, multinational, phase III, randomized clinical trial.

"This is the first clear demonstration of antifracture efficacy for an osteoporosis agent in male osteoporosis," said Dr. Steven Boonen in presenting the study results at the annual meeting of the American Society for Bone and Mineral Research.

"These findings suggest the use of zoledronic acid as a treatment option in male patients, particularly because annual infusions ensure that patients will have the full effect of treatment for at least the next year," added Dr. Boonen, professor of geriatric medicine and head of the gerontology and geriatrics section at Catholic University of Leuven (Belgium).

He reported on 1,199 men (mean age, 66 years) with primary osteoporosis or osteoporosis secondary to hypogonadism who were randomized in a double-blind fashion to a once-yearly 15-minute infusion of 5 mg of zoledronic acid (Reclast) or placebo at 134 centers. At enrollment, 32% of the men had one or more vertebral fractures.

The primary study end point was the proportion of subjects with one or more new vertebral fractures during 2 years of follow-up. The rate was 1.6% in men assigned to zoledronic acid and 4.9% in placebo-treated controls, which translated to a highly significant 67% relative risk reduction. The 12-month rate was 0.9% in the zoledronic acid group vs. 2.8% in controls, for a 68% relative risk reduction.

The incidence of moderate to severe vertebral fractures was similarly reduced by 63% in zoledronic acid recipients, compared with controls.

Men on zoledronic acid had a stable 60% reduction in levels of the bone turnover biomarker CTx, compared with the placebo group, throughout the study.

At 2 years, bone mineral density was roughly 6% greater at the spine and 2% greater at the total hip in the zoledronic acid group, compared with controls.

"All of these findings are remarkably similar in magnitude to the risk reductions that have been documented with zoledronic acid in the pivotal fracture trial in postmenopausal osteoporosis," the geriatrician observed.

Men on zoledronic acid also experienced a smaller height loss, compared with controls (mean, 2.34 vs. 4.49 mm).

No major safety issues arose in the study. Similar numbers of patients in both study arms dropped out of the trial because of adverse events.

At present, zoledronic acid’s approved indications include treatment to increase bone mass in men with osteoporosis.

Dr. Boonen disclosed that he has received research grants from and serves as a consultant to Novartis.

DENVER – Once-yearly intravenous zoledronic acid in men with osteoporosis reduced their risk of vertebral fractures by 67% over 2 years, compared with placebo, in a large, multinational, phase III, randomized clinical trial.

"This is the first clear demonstration of antifracture efficacy for an osteoporosis agent in male osteoporosis," said Dr. Steven Boonen in presenting the study results at the annual meeting of the American Society for Bone and Mineral Research.

"These findings suggest the use of zoledronic acid as a treatment option in male patients, particularly because annual infusions ensure that patients will have the full effect of treatment for at least the next year," added Dr. Boonen, professor of geriatric medicine and head of the gerontology and geriatrics section at Catholic University of Leuven (Belgium).

He reported on 1,199 men (mean age, 66 years) with primary osteoporosis or osteoporosis secondary to hypogonadism who were randomized in a double-blind fashion to a once-yearly 15-minute infusion of 5 mg of zoledronic acid (Reclast) or placebo at 134 centers. At enrollment, 32% of the men had one or more vertebral fractures.

The primary study end point was the proportion of subjects with one or more new vertebral fractures during 2 years of follow-up. The rate was 1.6% in men assigned to zoledronic acid and 4.9% in placebo-treated controls, which translated to a highly significant 67% relative risk reduction. The 12-month rate was 0.9% in the zoledronic acid group vs. 2.8% in controls, for a 68% relative risk reduction.

The incidence of moderate to severe vertebral fractures was similarly reduced by 63% in zoledronic acid recipients, compared with controls.

Men on zoledronic acid had a stable 60% reduction in levels of the bone turnover biomarker CTx, compared with the placebo group, throughout the study.

At 2 years, bone mineral density was roughly 6% greater at the spine and 2% greater at the total hip in the zoledronic acid group, compared with controls.

"All of these findings are remarkably similar in magnitude to the risk reductions that have been documented with zoledronic acid in the pivotal fracture trial in postmenopausal osteoporosis," the geriatrician observed.

Men on zoledronic acid also experienced a smaller height loss, compared with controls (mean, 2.34 vs. 4.49 mm).

No major safety issues arose in the study. Similar numbers of patients in both study arms dropped out of the trial because of adverse events.

At present, zoledronic acid’s approved indications include treatment to increase bone mass in men with osteoporosis.

Dr. Boonen disclosed that he has received research grants from and serves as a consultant to Novartis.

SAN DIEGO – A novel once-daily oral calcitonin tablet hit all of its efficacy and safety end points in a phase III clinical trial for treatment of postmenopausal osteoporosis.

The oral formulation of recombinant salmon calcitonin, known as Ostora, proved significantly more effective at building bone mineral density than conventional nasal calcitonin in the 18-site, multinational, double-blind, double-placebo ORACAL trial, Dr. Neil Binkley reported at the annual meeting of the American Society for Bone and Mineral Research.

ORACAL involved 565 postmenopausal women with osteoporosis and a mean age of 66 years. They were randomized 4:3:2 to once-daily bedtime therapy with oral calcitonin at 200 mcg, conventional nasal calcitonin at 200 IU, or placebo.

The absolute change in lumbar spine bone mineral density at 48 weeks – the primary study end point – showed a relatively modest 1.5% increase in the oral calcitonin group. But this was significantly greater than the 0.8% increase with the commercially available nasal calcitonin, which in turn was significantly better than the placebo response.

Potential safety issues with the bisphosphonates and other currently available medications have led many osteoporosis patients to decline therapy, while other women stop treatment due to side effects. Calcitonin, in contrast, has a 30-year history of safe prescription use via the intranasal and injectable routes. An oral formulation "might improve convenience and compliance with calcitonin therapy," observed Dr. Binkley, an endocrinologist at the University of Wisconsin, Madison.

Salmon calcitonin is an analog of human calcitonin that’s 30- to 50-fold more potent in suppressing osteoclast resorption.

In the ORACAL trial, levels of CTx (C-terminal telopeptide), a biomarker of bone resorption, dropped by 30% in the oral calcitonin group at 48 weeks, compared with 11% reductions in the nasal calcitonin and placebo arms.

Only 6.5% of women assigned to oral calcitonin developed anticalcitonin antibodies, compared with 32.5% of those on nasal calcitonin. This suggests delivery of the agent via the gastrointestinal tract is less immunogenic than the nasal mucosa. In any case, the production of antibodies had no apparent impacts on safety or efficacy, the endocrinologist continued.

The side effect picture in the oral and nasal calcitonin groups mirrored that in placebo-treated controls.

Tarsa Therapeutics, which is developing oral calcitonin, estimates at least 2 million American women have discontinued osteoporosis treatment. The company plans to file with the Food and Drug Administration for marketing approval later this year and with the European regulatory agency next year.

In addition, the company is developing oral calcitonin for the prevention of osteoporosis in postmenopausal women with osteopenia. A double-blind phase II trial is underway.

Dr. Binkley disclosed he has received a research grant from Tarsa, which sponsored the phase III trial.

SAN DIEGO – A novel once-daily oral calcitonin tablet hit all of its efficacy and safety end points in a phase III clinical trial for treatment of postmenopausal osteoporosis.

The oral formulation of recombinant salmon calcitonin, known as Ostora, proved significantly more effective at building bone mineral density than conventional nasal calcitonin in the 18-site, multinational, double-blind, double-placebo ORACAL trial, Dr. Neil Binkley reported at the annual meeting of the American Society for Bone and Mineral Research.

ORACAL involved 565 postmenopausal women with osteoporosis and a mean age of 66 years. They were randomized 4:3:2 to once-daily bedtime therapy with oral calcitonin at 200 mcg, conventional nasal calcitonin at 200 IU, or placebo.

The absolute change in lumbar spine bone mineral density at 48 weeks – the primary study end point – showed a relatively modest 1.5% increase in the oral calcitonin group. But this was significantly greater than the 0.8% increase with the commercially available nasal calcitonin, which in turn was significantly better than the placebo response.

Potential safety issues with the bisphosphonates and other currently available medications have led many osteoporosis patients to decline therapy, while other women stop treatment due to side effects. Calcitonin, in contrast, has a 30-year history of safe prescription use via the intranasal and injectable routes. An oral formulation "might improve convenience and compliance with calcitonin therapy," observed Dr. Binkley, an endocrinologist at the University of Wisconsin, Madison.

Salmon calcitonin is an analog of human calcitonin that’s 30- to 50-fold more potent in suppressing osteoclast resorption.

In the ORACAL trial, levels of CTx (C-terminal telopeptide), a biomarker of bone resorption, dropped by 30% in the oral calcitonin group at 48 weeks, compared with 11% reductions in the nasal calcitonin and placebo arms.

Only 6.5% of women assigned to oral calcitonin developed anticalcitonin antibodies, compared with 32.5% of those on nasal calcitonin. This suggests delivery of the agent via the gastrointestinal tract is less immunogenic than the nasal mucosa. In any case, the production of antibodies had no apparent impacts on safety or efficacy, the endocrinologist continued.

The side effect picture in the oral and nasal calcitonin groups mirrored that in placebo-treated controls.

Tarsa Therapeutics, which is developing oral calcitonin, estimates at least 2 million American women have discontinued osteoporosis treatment. The company plans to file with the Food and Drug Administration for marketing approval later this year and with the European regulatory agency next year.

In addition, the company is developing oral calcitonin for the prevention of osteoporosis in postmenopausal women with osteopenia. A double-blind phase II trial is underway.

Dr. Binkley disclosed he has received a research grant from Tarsa, which sponsored the phase III trial.

SAN DIEGO – A novel once-daily oral calcitonin tablet hit all of its efficacy and safety end points in a phase III clinical trial for treatment of postmenopausal osteoporosis.

The oral formulation of recombinant salmon calcitonin, known as Ostora, proved significantly more effective at building bone mineral density than conventional nasal calcitonin in the 18-site, multinational, double-blind, double-placebo ORACAL trial, Dr. Neil Binkley reported at the annual meeting of the American Society for Bone and Mineral Research.

ORACAL involved 565 postmenopausal women with osteoporosis and a mean age of 66 years. They were randomized 4:3:2 to once-daily bedtime therapy with oral calcitonin at 200 mcg, conventional nasal calcitonin at 200 IU, or placebo.

The absolute change in lumbar spine bone mineral density at 48 weeks – the primary study end point – showed a relatively modest 1.5% increase in the oral calcitonin group. But this was significantly greater than the 0.8% increase with the commercially available nasal calcitonin, which in turn was significantly better than the placebo response.

Potential safety issues with the bisphosphonates and other currently available medications have led many osteoporosis patients to decline therapy, while other women stop treatment due to side effects. Calcitonin, in contrast, has a 30-year history of safe prescription use via the intranasal and injectable routes. An oral formulation "might improve convenience and compliance with calcitonin therapy," observed Dr. Binkley, an endocrinologist at the University of Wisconsin, Madison.

Salmon calcitonin is an analog of human calcitonin that’s 30- to 50-fold more potent in suppressing osteoclast resorption.

In the ORACAL trial, levels of CTx (C-terminal telopeptide), a biomarker of bone resorption, dropped by 30% in the oral calcitonin group at 48 weeks, compared with 11% reductions in the nasal calcitonin and placebo arms.

Only 6.5% of women assigned to oral calcitonin developed anticalcitonin antibodies, compared with 32.5% of those on nasal calcitonin. This suggests delivery of the agent via the gastrointestinal tract is less immunogenic than the nasal mucosa. In any case, the production of antibodies had no apparent impacts on safety or efficacy, the endocrinologist continued.

The side effect picture in the oral and nasal calcitonin groups mirrored that in placebo-treated controls.

Tarsa Therapeutics, which is developing oral calcitonin, estimates at least 2 million American women have discontinued osteoporosis treatment. The company plans to file with the Food and Drug Administration for marketing approval later this year and with the European regulatory agency next year.

In addition, the company is developing oral calcitonin for the prevention of osteoporosis in postmenopausal women with osteopenia. A double-blind phase II trial is underway.

Dr. Binkley disclosed he has received a research grant from Tarsa, which sponsored the phase III trial.

DENVER – New data indicate that obesity in postmenopausal women doesn’t protect against fractures, contrary to the conventional wisdom.

Indeed, postmenopausal obesity actually appears to be a risk factor for fractures at selected sites, Dr. Juliet E. Compston reported at the annual meeting of the American Society for Bone and Mineral Research.

This is a finding with major public health implications because of the growing obesity epidemic. The ramifications are especially pressing in light of new evidence that obese postmenopausal women who experience a fracture are far less likely than nonobese women to be placed on bone-protective medication, said Dr. Compston, professor of bone medicine at the University of Cambridge (England).

She reported on a study of 44,534 postmenopausal women (mean age, 67 years) in the United States and nine other countries who are participating in the ongoing, prospective, observational GLOW (Global Longitudinal Study of Osteoporosis in Women). At enrollment, 23.4% of the women had a body mass index of 30 kg/m² or more, and 1.7% were underweight (defined as a BMI less than 18.5).

The prevalence of fracture at baseline was 23% in obese women, 24% in nonobese women, and 32% in the underweight study population. The incidence of one or more new fractures during 2 years of follow-up was 6.4% in the obese and similar at 6.8% in the nonobese women, compared with 7.3% in the underweight group.

Thus, nearly one in four postmenopausal women with a fracture is obese. As the obesity rate continues to climb in the developed world, fractures in the obese will increasingly contribute to the overall burden of fractures in the postmenopausal population, Dr. Compston observed.

The higher prevalence and incidence of fracture in underweight postmenopausal women comes as no surprise; low BMI is recognized as a major risk factor for fracture. What was surprising, though, was that only 27% of obese GLOW participants with an incident fracture were placed on bone-protective medication for secondary prevention.

In contrast, the treatment rate in nonobese women with an incident fracture was 41%, and in underweight women it was 57%. The likely explanation for the markedly lower treatment rate in the obese group is the widespread belief that obesity protects against fractures, according to Dr. Compston.

Incident fractures of the ankle and tibia were significantly more common and wrist fractures were less common in obese women, compared with nonobese study participants.

The obese subjects with an incident fracture had significantly higher rates of several comorbid conditions – asthma, emphysema, and type 1 diabetes – than did nonobese women. They also were more likely than nonobese participants with an incident fracture to have a baseline history of two or more falls within the past 2 years. They had more mobility issues as well, as reflected in their increased rate of self-reported need for arm assistance in standing up. It’s likely that reduced mobility and increased risk of falling play an important role in the pathogenesis of fractures in obese postmenopausal women, although this is an issue that needs further study, she observed.

In a separate presentation, Helena Johansson presented an analysis of BMI and fracture risk in 281,637 women drawn from 27 prospective, population-based cohort studies that were conducted in more than two dozen countries. The women were aged 20-105 years (mean age, 63 years).

A total of 18,441 osteoporotic fractures occurred in the study population during a mean 4.8 years of follow-up. After adjustment for bone mineral density, obesity proved to be a risk factor for fracture. For example, women with a BMI of 34 had an adjusted 14% increased risk of osteoporotic fracture, compared with those having a BMI of 26, an elevation in risk that, while modest, was statistically significant. And women having a BMI of 34 had a more impressive adjusted 60% increased risk of humerus or elbow fracture, added Ms. Johansson, a statistician at the University of Gothenburg (Sweden).

Dr. Compston declared having no relevant financial disclosures. GLOW is supported by grants from Sanofi-Aventis and Warner Chilcott. Ms. Johansson declared having no relevant financial disclosures.

DENVER – New data indicate that obesity in postmenopausal women doesn’t protect against fractures, contrary to the conventional wisdom.

Indeed, postmenopausal obesity actually appears to be a risk factor for fractures at selected sites, Dr. Juliet E. Compston reported at the annual meeting of the American Society for Bone and Mineral Research.

This is a finding with major public health implications because of the growing obesity epidemic. The ramifications are especially pressing in light of new evidence that obese postmenopausal women who experience a fracture are far less likely than nonobese women to be placed on bone-protective medication, said Dr. Compston, professor of bone medicine at the University of Cambridge (England).

She reported on a study of 44,534 postmenopausal women (mean age, 67 years) in the United States and nine other countries who are participating in the ongoing, prospective, observational GLOW (Global Longitudinal Study of Osteoporosis in Women). At enrollment, 23.4% of the women had a body mass index of 30 kg/m² or more, and 1.7% were underweight (defined as a BMI less than 18.5).

The prevalence of fracture at baseline was 23% in obese women, 24% in nonobese women, and 32% in the underweight study population. The incidence of one or more new fractures during 2 years of follow-up was 6.4% in the obese and similar at 6.8% in the nonobese women, compared with 7.3% in the underweight group.

Thus, nearly one in four postmenopausal women with a fracture is obese. As the obesity rate continues to climb in the developed world, fractures in the obese will increasingly contribute to the overall burden of fractures in the postmenopausal population, Dr. Compston observed.

The higher prevalence and incidence of fracture in underweight postmenopausal women comes as no surprise; low BMI is recognized as a major risk factor for fracture. What was surprising, though, was that only 27% of obese GLOW participants with an incident fracture were placed on bone-protective medication for secondary prevention.

In contrast, the treatment rate in nonobese women with an incident fracture was 41%, and in underweight women it was 57%. The likely explanation for the markedly lower treatment rate in the obese group is the widespread belief that obesity protects against fractures, according to Dr. Compston.

Incident fractures of the ankle and tibia were significantly more common and wrist fractures were less common in obese women, compared with nonobese study participants.

The obese subjects with an incident fracture had significantly higher rates of several comorbid conditions – asthma, emphysema, and type 1 diabetes – than did nonobese women. They also were more likely than nonobese participants with an incident fracture to have a baseline history of two or more falls within the past 2 years. They had more mobility issues as well, as reflected in their increased rate of self-reported need for arm assistance in standing up. It’s likely that reduced mobility and increased risk of falling play an important role in the pathogenesis of fractures in obese postmenopausal women, although this is an issue that needs further study, she observed.

In a separate presentation, Helena Johansson presented an analysis of BMI and fracture risk in 281,637 women drawn from 27 prospective, population-based cohort studies that were conducted in more than two dozen countries. The women were aged 20-105 years (mean age, 63 years).

A total of 18,441 osteoporotic fractures occurred in the study population during a mean 4.8 years of follow-up. After adjustment for bone mineral density, obesity proved to be a risk factor for fracture. For example, women with a BMI of 34 had an adjusted 14% increased risk of osteoporotic fracture, compared with those having a BMI of 26, an elevation in risk that, while modest, was statistically significant. And women having a BMI of 34 had a more impressive adjusted 60% increased risk of humerus or elbow fracture, added Ms. Johansson, a statistician at the University of Gothenburg (Sweden).

Dr. Compston declared having no relevant financial disclosures. GLOW is supported by grants from Sanofi-Aventis and Warner Chilcott. Ms. Johansson declared having no relevant financial disclosures.

DENVER – New data indicate that obesity in postmenopausal women doesn’t protect against fractures, contrary to the conventional wisdom.

Indeed, postmenopausal obesity actually appears to be a risk factor for fractures at selected sites, Dr. Juliet E. Compston reported at the annual meeting of the American Society for Bone and Mineral Research.

This is a finding with major public health implications because of the growing obesity epidemic. The ramifications are especially pressing in light of new evidence that obese postmenopausal women who experience a fracture are far less likely than nonobese women to be placed on bone-protective medication, said Dr. Compston, professor of bone medicine at the University of Cambridge (England).

She reported on a study of 44,534 postmenopausal women (mean age, 67 years) in the United States and nine other countries who are participating in the ongoing, prospective, observational GLOW (Global Longitudinal Study of Osteoporosis in Women). At enrollment, 23.4% of the women had a body mass index of 30 kg/m² or more, and 1.7% were underweight (defined as a BMI less than 18.5).

The prevalence of fracture at baseline was 23% in obese women, 24% in nonobese women, and 32% in the underweight study population. The incidence of one or more new fractures during 2 years of follow-up was 6.4% in the obese and similar at 6.8% in the nonobese women, compared with 7.3% in the underweight group.

Thus, nearly one in four postmenopausal women with a fracture is obese. As the obesity rate continues to climb in the developed world, fractures in the obese will increasingly contribute to the overall burden of fractures in the postmenopausal population, Dr. Compston observed.

The higher prevalence and incidence of fracture in underweight postmenopausal women comes as no surprise; low BMI is recognized as a major risk factor for fracture. What was surprising, though, was that only 27% of obese GLOW participants with an incident fracture were placed on bone-protective medication for secondary prevention.

In contrast, the treatment rate in nonobese women with an incident fracture was 41%, and in underweight women it was 57%. The likely explanation for the markedly lower treatment rate in the obese group is the widespread belief that obesity protects against fractures, according to Dr. Compston.

Incident fractures of the ankle and tibia were significantly more common and wrist fractures were less common in obese women, compared with nonobese study participants.

The obese subjects with an incident fracture had significantly higher rates of several comorbid conditions – asthma, emphysema, and type 1 diabetes – than did nonobese women. They also were more likely than nonobese participants with an incident fracture to have a baseline history of two or more falls within the past 2 years. They had more mobility issues as well, as reflected in their increased rate of self-reported need for arm assistance in standing up. It’s likely that reduced mobility and increased risk of falling play an important role in the pathogenesis of fractures in obese postmenopausal women, although this is an issue that needs further study, she observed.

In a separate presentation, Helena Johansson presented an analysis of BMI and fracture risk in 281,637 women drawn from 27 prospective, population-based cohort studies that were conducted in more than two dozen countries. The women were aged 20-105 years (mean age, 63 years).

A total of 18,441 osteoporotic fractures occurred in the study population during a mean 4.8 years of follow-up. After adjustment for bone mineral density, obesity proved to be a risk factor for fracture. For example, women with a BMI of 34 had an adjusted 14% increased risk of osteoporotic fracture, compared with those having a BMI of 26, an elevation in risk that, while modest, was statistically significant. And women having a BMI of 34 had a more impressive adjusted 60% increased risk of humerus or elbow fracture, added Ms. Johansson, a statistician at the University of Gothenburg (Sweden).

Dr. Compston declared having no relevant financial disclosures. GLOW is supported by grants from Sanofi-Aventis and Warner Chilcott. Ms. Johansson declared having no relevant financial disclosures.