Asheville, NC – Because of its very slow and insidious nature, osteoporosis is challenging to evaluate. Bone loss begins years if not decades before patients suffer fractures. Yet long-term daily drug therapy carries significant risk of side effects, a big price tag, and major compliance challenges.
The key is to determine early on who is at greatest risk for fracture, and who truly needs intensive therapy. “We’re all concerned about long-term use of bisphosphonates. The questions are, who really needs them, who does not, and when to stop therapy once it’s begun?” said Jill Vargo, MD, Co-Director of the Asheville Arthritis & Osteoporosis Center.
Speaking at the annual winter meeting of the North Carolina Academy of Family Physicians, Dr. Vargo said these are important questions given that an estimated 34 million Americans have low bone mineral density (BMD) of the hip, and there are roughly 300,000 hip fractures annually. That number is going to soar in the next decade, as the population ages.
In general, anyone at risk for osteoporosis and bone fractures should:
- Take Vitamin D (and Calcium) Daily: Aim for serum vitamin D levels of 50 ng/ml. For most patients that means 1,000-2,000 IU per day.
- Engage in Regular Weight-Bearing Exercise: Not only does it strengthen bone and muscle, it also improves coordination and balance. Exercise need not be strenuous or intensive, just frequent and enjoyable.
- Get Involved in a Fall Prevention Program: It is not osteoporosis itself that disables someone, it is the falls and fractures. Patients and their families need to learn how to minimize fall risk.
- Avoid Alcohol & Tobacco: Smoking accelerates bone loss, to say nothing of its other health compromising effects. Heavy alcohol intake can impair balance, coordination and reflex speed, increasing risk of falls.
Here are a few evaluation and management tips that Dr. Vargo & her colleagues have gathered over their years of practice focused on osteoporosis:
Test Early, Test Repeatedly: DEXA is still the gold standard method for evaluating BMD. Qualitative Computed Tomography (QCT) may be better, but it involves a hefty dose of radiation, and it is still too costly for widespread use.
As a rule, get central (hip & spine) DEXAs on all women aged 65 years or more, and all men from age 70 and over. Bear in mind that women tend to lose BMD at the fastest rate in the 3-5 years after menopause, so it makes sense to test peri-menopausal women, especially if they have significant osteoporosis risk factors (family history, recent fracture, taking bone-depleting medications, etc). Likewise, start getting DEXAs on men over 50 if they have high-risk profiles.
Since bone loss is gradual but progressive, one DEXA by itself really does not tell you much. The true picture emerges with repeated scans. Generally, intervals of 2-3 years make sense, unless there’s a specific change in a patient’s life (ie, he or she starts a course of steroids or other bone-depleting drug).
Anyone already on a bisphosphonate or some other bone-building therapy should be re-tested every couple of years, to determine if treatment is having any impact. If there are no significant improvements after 5 or 6 years, despite diligent compliance, you need to re-think your treatment strategy.
Urine n-teleopeptide, a marker of bone turnover and osteoclast activity, is not diagnostic but it is useful for figuring out who’s losing bone rapidly. It is also good for monitoring treatment response. “I get this test for all people who have been on a drug for 5 years or more. If the number is over 7 despite continuous treatment, I stop the drug.”
Don’t Be Spineless: Vertebral fractures are very common, often asymptomatic, and bad news because they are harbingers of future fractures, said Dr. Vargo.
Vertebral breaks, usually in the T8 to L4 vertebrae, tend to occur at much younger ages (mean is around 60 years) hip fractures (mean age of approximately 70). This is because trabecular bone loss happens before cortical bone loss.
Pay close attention to the thoracic and lumbar spine in anyone with low T-scores or osteoporosis risk factors. Among people over 65, roughly 20% will have asymptomatic vertebral fractures. But because they’re often asymptomatic, you’re only going to see vertebral fractures if you start looking for them.
“Fracture always trumps T-score. I don’t care what someone’s T-score is, once a person starts breaking bone, they’re at very high risk and I start treating.”
Vertebral fracture assessment based on low-radiation densitometry (aka, VFA Morphometry), is not considered definitively diagnostic at this point, but it can be helpful in the evaluation.
Get Hip: You need to look carefully at total hip and femoral neck density. “The femoral neck will actually give you the cleanest and best BMD numbers.” Dr. Vargo said. The three key measurement sites are the lumbar spine, total hip and femoral neck, and you should make your treatment decisions based on the lowest, not the highest score.
Numbers Are Not Enough: “Always look at the x-ray pictures. If you don’t get the picture, you’re going to miss a lot of stuff, because the numbers really are not enough.” Again, Dr. Vargo advised looking closely at the spine. “If the L1-L4 vertebrae look all smashed up, or there’s lots of osteoarthritis, the DEXA is invalid.”
Look at the Bigger Picture: Bone loss occurs in a broader metabolic context. When evaluating a patient, consider nutritional status (especially calcium, phosphorus and vitamin D levels), liver and kidney function, as well as thyroid and parathyroid hormone levels. Always look for celiac disease, as it tends to predispose people to bone loss. In men, check testosterone levels. Keep in mind that anyone with a chronic inflammatory condition, rheumatoid disease, or systemic metabolic disorder (including diabetes) will be at increased osteoporosis risk.
Avoid the ‘Roids: Corticosteroids are bad news for bone, so keep a close eye on any patient on long-term steroid therapy, regardless of why they were prescribed these drugs. Try to avoid using steroids in patients at high fracture risk. Watch women on depo-provera contraception very closely, as it has steroid-like, bone-depleting effects. “I get DEXAs on all my provera patients. If BMD is decreasing, we look for different methods of birth control.”
D is for Density: There’s no question vitamin D promotes bone density, so all patients at risk of osteoporosis ought to be taking it. “Don’t be afraid of vitamin D. I saw a patient once with a serum level of 254 (due to excessive supplementation). There were no symptoms and no indication of harm.” In general, you want the serum level up over 30 ng/ml. “I always shoot for 50.”
Be aware that many patients in the osteoporosis age bracket are severely deficient. Likewise, those on dilantin and other seizure drugs are at risk for deficiency because these agents block absorption of vitamin D. “Dilantin is a major risk factor for bone loss,” Dr. Vargo said.
Once serum vitamin D drops below 10 ng/ml, and all physiological stores have been exhausted, it can be very difficult to replete back up to healthy levels with standard over-the-counter supplements. Special high-dose prescription products will be needed, and even then it is challenging. Ideally, you want to prevent severe deficiency.
To read more about the problems of long-term bisphosphonate therapy, subscribe to our Premium Web Access and read Dr. Tori Hudson’s article, “Are Bisphosphonates Really Necessary for Osteoporosis Prevention?”