If you have IBD, your doctor has probably prescribed steroids such as prednisone to decrease inflammation during an acute flare-up. The common side effects of steroids range from annoying to debilitating but they will go away when the dosage is tapered down and discontinued. However, many people who are prescribed steroids for an inflammatory condition are not aware of the potentially serious and permanent effects that can occur with high dosages and/or prolonged use. One of these conditions is steroid-induced osteoporosis.
Osteoporosis
Osteoporosis is a weakening of the bones, which causes them to lose their density and become more brittle and susceptible to fracture. It is largely thought of as a disease of post-menopausal women, which is true in part, but it could happen to men or women of any age who have risk factors. Risk factors include:
- Age (over 65)
- Alcohol abuse
- Caucasian or Asian descent
- Certain medications (including steroids & thyroid hormones)
- Early menopause
- Family history
- Inadequate calcium intake
- Previous fracture
- Sedentary lifestyle
- Smoking
- Thin/small build (less than 70 kg or 154 lbs)
Steroid-induced Osteoporosis
While steroids do decrease inflammation, they also decrease the formation of new bone, increase the breakdown of old bone, and decrease the absorption of calcium from food by the body. In the case of IBD, the development of osteoporosis may be compounded by the already low amount of calcium absorbed by the body.
Diagnosis
Osteoporosis is diagnosed with a test called dual-energy x-ray absorptiometry (DEXA). DEXA is more sensitive than a regular x-ray and can find bone loss in its early stages. It is painless, and takes about 10 minutes to complete. The American College of Rheumatology recommends DEXA testing at the start of steroid treatment and periodically thereafter (such as yearly) while therapy is continued. Osteoporosis tends to be more common in Crohn’s disease (CD) than ulcerative colitis (UC), so a baseline DEXA to catch any early bone loss is recommended for all CD patients. DEXA is only recommended in patients with UC who are prescribed steroids as a long-term therapy.
Treatment
Tapering steroids. To prevent early bone loss, steroids should only be used in the lowest effectual dosage for the shortest amount of time. Steroid treatment can be extremely useful for many inflammatory conditions, but the benefits should be weighed against the potential for serious and permanent side effects such as osteoporosis.
Supplements. Because calcium is absorbed in the small intestine, malabsorption occurs mainly in people with CD who have inflammation in the small intestine. People with UC which manifests in the large intestine may have better calcium absorption. Calcium supplements (1,500 mg per day) may be recommended to treat or prevent early bone loss, but is not as effective in treating osteoporosis as other therapies listed below.
It’s important to know that calcium doesn’t work alone – it needs vitamin D to be absorbed by the body. Vitamin D is synthesized in the skin when it is exposed to sunlight and like calcium, is poorly absorbed by people with active inflammation in the small intestine caused by CD. Daily supplementation with 400 u of vitamin D may be recommended to combat early bone loss.
Bisphosphonates. Alendronate (Fosamax) and etidronate (Didronel) are bisphosphonates that are used to help bone breakdown and preserve bone mass. These medications may also actually increase bone density in the spine and hip. However, they have not been fully tested in IBD patients with steroid induced osteoporosis. Bisphosphonates are currently the only class of drugs that are FDA approved for treating osteoporosis in men.
Raloxifene (Evista). Raloxifene is a selective estrogen receptor modulator for use in post-menopausal women who have osteoporosis. It has the same benefits of estrogen therapy on bone health but has not been shown to increase the risk of cancer. Raloxifene may cause hot flashes, and is not for use in women who have a history of blood clots.
Calcitonin (Calcimar, Cibacalcin, Miacalcin). Calcitonin helps slow bone loss and prevent fractures in the spine but not in the hip. This medication is administered as a nasal spray, and may cause irritation in the nasal passages. Calcitonin is typically useful for high risk patients who can’t take or are intolerant to therapy with bisphosphonates or estrogen.
Tamoxifen (Nolvadex). Tamoxifen is a synthetic hormone which has been used for treating breast cancer for over 20 years. This drug has many of the same effects of estrogen on bone and other cells, but also may have serious side effects such as an increased risk of uterine and endometrial cancer.
Statins. This class of drugs is used to treat high cholesterol. In early studies, statins showed promise in lowering the risk of bone fractures. More recent studies show the opposite effect; statins may not reduce the risk of fracture or increase bone density.
