Confirm Osteoporosis by Bone Biopsy Before Treatment in Advanced CKD

TAMPA — Diagnosis of osteoporosis in patients with advanced chronic kidney disease cannot be accomplished simply on the basis of T score or bone fragility, Dr. Paul Miller said at the annual meeting of the International Society for Clinical Densitometry.

“People with more severe chronic kidney disease can have a whole host of metabolic bone diseases that mimic osteoporosis, either by bone density criteria or fractures, and yet may not be osteoporosis,” said Dr. Miller, medical director of a bone research center in Lakewood, Colo.

Patients with advanced chronic kidney disease (CKD) are at increased risk for osteoporosis, resulting from a variety of factors. Chronic heparin use and steroid use may be risk factors for patients on dialysis. In transplant patients, the use of calcineurin inhibitors can cause high bone turnover, increasing bone fragility.

Hypogonadism, hyperprolacti- nemia, poor nutrition, vitamin D deficiency, and hyperparathyroidism are other osteoporosis risk factors in CKD patients. They may be more likely than others to develop forms of osteoporosis that could be treated effectively by bisphosphonates, said Dr. Miller.

However, CKD patients are also at risk for other bone metabolic diseases, including osteitis fibrosa cystica, osteomalacia, and adynamic bone disease. Bisphosphonates may be contraindicated in patients with severe adynamic bone disease or osteomalacia. “We don't have data, but it doesn't make sense to try to use drugs that reduce bone turnover to try to improve bone strength when you already have a low bone-turnover disease such as adynamic bone disease or osteomalacia,” he said.

Renal impairment is associated with increased fracture risk, even in patients without severe renal disease. A recent analysis of data from the Study of Osteoporotic Fractures cohort showed that age-related reduction in renal function that causes mild to moderate renal impairment is associated with increased hip fracture risk in older women (Arch. Intern. Med. 2007;167:133–9).

Diagnosis of osteoporosis in CKD patients must exclude other causes of low bone mineral density (BMD) or fragility fractures. The latter can be seen in transplant recipients and in patients with severe hyperparathyroidism, adynamic bone disease, or osteomalacia.

Severe adynamic bone disease and osteomalacia are considered to have low prevalence in CKD before stage 5 disease, according to Dr. Miller, and mild secondary hyperparathyroidism in that patient population does not cause fractures. Therefore, if the biochemical profile does not suggest severe hyperparathyroidism or other renal bone disease, low T scores based on the World Health Organization criteria or fragility fractures should be sufficient for the diagnosis of osteoporosis in patients with stage 1–4 CKD, he said.

For patients with stage 5 CKD who have low BMD or fragility fractures, a double tetracycline-labeled bone biopsy is necessary to rule out other causes of metabolic bone disease and confirm a diagnosis of osteoporosis.

Caution is advised for bisphosphonate treatment of advanced CKD patients, said Dr. Miller. Labeling recommendations for bisphosphonates exclude patients with creatinine clearance under 35 mL/min, largely because of a lack of data about bisphosphonates in CKD patients.

TAMPA — Diagnosis of osteoporosis in patients with advanced chronic kidney disease cannot be accomplished simply on the basis of T score or bone fragility, Dr. Paul Miller said at the annual meeting of the International Society for Clinical Densitometry.

“People with more severe chronic kidney disease can have a whole host of metabolic bone diseases that mimic osteoporosis, either by bone density criteria or fractures, and yet may not be osteoporosis,” said Dr. Miller, medical director of a bone research center in Lakewood, Colo.

Patients with advanced chronic kidney disease (CKD) are at increased risk for osteoporosis, resulting from a variety of factors. Chronic heparin use and steroid use may be risk factors for patients on dialysis. In transplant patients, the use of calcineurin inhibitors can cause high bone turnover, increasing bone fragility.

Hypogonadism, hyperprolacti- nemia, poor nutrition, vitamin D deficiency, and hyperparathyroidism are other osteoporosis risk factors in CKD patients. They may be more likely than others to develop forms of osteoporosis that could be treated effectively by bisphosphonates, said Dr. Miller.

However, CKD patients are also at risk for other bone metabolic diseases, including osteitis fibrosa cystica, osteomalacia, and adynamic bone disease. Bisphosphonates may be contraindicated in patients with severe adynamic bone disease or osteomalacia. “We don't have data, but it doesn't make sense to try to use drugs that reduce bone turnover to try to improve bone strength when you already have a low bone-turnover disease such as adynamic bone disease or osteomalacia,” he said.

Renal impairment is associated with increased fracture risk, even in patients without severe renal disease. A recent analysis of data from the Study of Osteoporotic Fractures cohort showed that age-related reduction in renal function that causes mild to moderate renal impairment is associated with increased hip fracture risk in older women (Arch. Intern. Med. 2007;167:133–9).

Diagnosis of osteoporosis in CKD patients must exclude other causes of low bone mineral density (BMD) or fragility fractures. The latter can be seen in transplant recipients and in patients with severe hyperparathyroidism, adynamic bone disease, or osteomalacia.

Severe adynamic bone disease and osteomalacia are considered to have low prevalence in CKD before stage 5 disease, according to Dr. Miller, and mild secondary hyperparathyroidism in that patient population does not cause fractures. Therefore, if the biochemical profile does not suggest severe hyperparathyroidism or other renal bone disease, low T scores based on the World Health Organization criteria or fragility fractures should be sufficient for the diagnosis of osteoporosis in patients with stage 1–4 CKD, he said.

For patients with stage 5 CKD who have low BMD or fragility fractures, a double tetracycline-labeled bone biopsy is necessary to rule out other causes of metabolic bone disease and confirm a diagnosis of osteoporosis.

Caution is advised for bisphosphonate treatment of advanced CKD patients, said Dr. Miller. Labeling recommendations for bisphosphonates exclude patients with creatinine clearance under 35 mL/min, largely because of a lack of data about bisphosphonates in CKD patients.

TAMPA — Diagnosis of osteoporosis in patients with advanced chronic kidney disease cannot be accomplished simply on the basis of T score or bone fragility, Dr. Paul Miller said at the annual meeting of the International Society for Clinical Densitometry.

“People with more severe chronic kidney disease can have a whole host of metabolic bone diseases that mimic osteoporosis, either by bone density criteria or fractures, and yet may not be osteoporosis,” said Dr. Miller, medical director of a bone research center in Lakewood, Colo.

Patients with advanced chronic kidney disease (CKD) are at increased risk for osteoporosis, resulting from a variety of factors. Chronic heparin use and steroid use may be risk factors for patients on dialysis. In transplant patients, the use of calcineurin inhibitors can cause high bone turnover, increasing bone fragility.

Hypogonadism, hyperprolacti- nemia, poor nutrition, vitamin D deficiency, and hyperparathyroidism are other osteoporosis risk factors in CKD patients. They may be more likely than others to develop forms of osteoporosis that could be treated effectively by bisphosphonates, said Dr. Miller.

However, CKD patients are also at risk for other bone metabolic diseases, including osteitis fibrosa cystica, osteomalacia, and adynamic bone disease. Bisphosphonates may be contraindicated in patients with severe adynamic bone disease or osteomalacia. “We don't have data, but it doesn't make sense to try to use drugs that reduce bone turnover to try to improve bone strength when you already have a low bone-turnover disease such as adynamic bone disease or osteomalacia,” he said.

Renal impairment is associated with increased fracture risk, even in patients without severe renal disease. A recent analysis of data from the Study of Osteoporotic Fractures cohort showed that age-related reduction in renal function that causes mild to moderate renal impairment is associated with increased hip fracture risk in older women (Arch. Intern. Med. 2007;167:133–9).

Diagnosis of osteoporosis in CKD patients must exclude other causes of low bone mineral density (BMD) or fragility fractures. The latter can be seen in transplant recipients and in patients with severe hyperparathyroidism, adynamic bone disease, or osteomalacia.

Severe adynamic bone disease and osteomalacia are considered to have low prevalence in CKD before stage 5 disease, according to Dr. Miller, and mild secondary hyperparathyroidism in that patient population does not cause fractures. Therefore, if the biochemical profile does not suggest severe hyperparathyroidism or other renal bone disease, low T scores based on the World Health Organization criteria or fragility fractures should be sufficient for the diagnosis of osteoporosis in patients with stage 1–4 CKD, he said.

For patients with stage 5 CKD who have low BMD or fragility fractures, a double tetracycline-labeled bone biopsy is necessary to rule out other causes of metabolic bone disease and confirm a diagnosis of osteoporosis.

Caution is advised for bisphosphonate treatment of advanced CKD patients, said Dr. Miller. Labeling recommendations for bisphosphonates exclude patients with creatinine clearance under 35 mL/min, largely because of a lack of data about bisphosphonates in CKD patients.