Straight Information About Bone Density Testing

You have all heard the term osteoporosis, a condition where the bones are not as mineralized/dense/strong as they should be, placing that person at increased risk of fracture. For wrist fracture secondary to a fall onto one’s extended arm; for vertebral fracture with resultant deformity in appearance and, if severe, difficulty in ambulating and breathing properly; and most problematically, for hip fracture. The resulting immobilization can have disastrous effects. A total of 40-50% of people with a hip fracture aged 80 and above and 20-25% of people age 70-80 will not live out the year after their hip fracture because of the blood clots, pneumonia and other maladies that accompany prolonged immobilization. The World Health Organization estimates that at least ten and possibly as many as 20 million men and women in the United States have osteoporosis and are at significantly increased risk for fracture.

Although there are treatments for osteoporosis, the best therapy is prevention. You don’t want to get osteoporosis.

“Osteopenia” (defined as a bone mineral density greater than one but less than 2.5 deviations below the mean) is a warning. It still increases your fracture risk, but no where near as much as osteoporosis (a bone density of greater than 2.5 below the mean). It is a warning to get treated!

Bone mineral density problems are much more prevalent in women compared to men. Why? Both testosterone and estrogen protect against bone loss. Although men’s testosterone certainly wanes with age, men do not experience the virtual disappearance of their protective sex steroids that women do.

Measuring bone mineral density in older patients (over 50 or 60 years), especially in women, is as justifiable as measuring lipids. Lipid testing and treatment for high cholesterol is accepted as an integral part of primary care, but bone densiometry and therapy for low bone density aren’t as readily accepted, partly because measurements and treatments for osteoporosis came along well after tests and treatments for heart disease and its risk factors.

The cost-effectiveness of bone density testing stacks up nicely against the value of lipid testing; people with cholesterol measurements in the highest quartile have four times the risk for heart disease compared with people whose measurements are in the lowest quartile, whereas the risk for hip fracture increases tenfold in people whose bone density is in the highest quartile compared with those in the lowest quartile. Heart disease risk increases from about 0.5% in the lowest LDL quartile to approximately 4% in the highest lipid quartile. Hip fracture risk increases from approximately 0.5% in the highest quartile to approximately 10% in the quartile with the lowest hip bone density.

Screening lipid levels in a 52-year-old woman and treating her for an LDL of greater than 160 costs approximately $400,000 per quality-adjusted life year. Screening bone density in a 65-year-old woman and treating her for a T-score of -2.5 costs approximately $25,000-30,000 (depending on medication) per quality-adjusted life year, which is considered cost-effective.

The National Osteoporosis Foundation recommends BMD testing for all women age 65 or older and for postmenopausal women with a risk factor for osteoporosis (those not on hormone therapy, very slender women, smokers, those with a family history of osteoporosis, those with a history of loss of periods when younger, men and women with a history of frequent corticosteroid intake, etc.). Screening is also recommended for the approximately 20-25% of men with lower testosterone levels (manifested by diminished energy, diminished sexual desire, etc.) as they age past 50 or 60.

The US Preventive Services Task Force recommends BMD measurements for all women over the age of 60. Medicare covers bone density tests for women over 65.

Bone mineral architecture is dynamic, always being re-formed, always breaking down. The idea is to build more than you break down. Adequate calcium, some magnesium and trace minerals, adequate Vitamin D, adequate protein and weight-bearing exercise are necessary to form new bone. However, if you are genetically or otherwise prone to lose excessive amounts of bone, all the calcium in the world will not protect you, and some other measure (low dose estrogens, testosterone, DHEA, a bisphosphonate medication such as Actonel®, Fosamax®, or Boniva®, a Serm such as Evista®) is necessary to protect you from this debilitating disease.

Bone density testing is a benefit of Medicare, most PPO insurances and some HMOs and may be done at radiology services and at the private offices of most certified clinical bone density practitioners. Cost prices range from approximately $175.00 at our office in Davis to approximately $400.00 or more at radiology services. Peripheral screens for low-risk individuals usually run $30-$50.

Michael Goodman, M.D. is a certified clinical bone densiometrist and gynecologist in practice in Davis, California.