Osteoporosis: Diagnosis and Treatment

Diagnosis

Vertebral fracture is the most common clinical manifestation of osteoporosis or osteopenia (a diagnosis of less severe bone loss), typically presenting as an asymptomatic incidental finding on x–ray. Fracture of the vertebrae usually occurs in the lower thoracic or upper lumbar region, and may occur after simple movements like bending over and lifting. Multiple fractures may result in pronounced thoracic kyphosis, sometimes called “dowager’s hump.”³ In the absence of fracture, pain is unlikely to be due to osteoporosis, but it could be due to osteomalacia or other bone disease.

In the absence of fragility fracture, radiological bone densitometry establishes the diagnosis of osteoporosis. Bone biopsy, which can ensure histologic diagnosis, is rarely performed. A history of fracture is not necessary for diagnosis.

Laboratory tests, particularly thyroid–stimulating hormone, complete blood count (CBC), 25–hydroxy vitamin D, serum protein electrophoresis, urine calcium, and a comprehensive metabolic panel (including calcium and phosphate), can help determine if osteoporosis is due to another disease process. Because many disease processes can contribute to osteoporosis, disease–specific diagnostic evaluations are necessary, based on results of clinical presentation and screening tests.

Treatment

The clinical focus should be on prevention, symptomatic therapy, and inhibition of disease progression. Lifestyle modification is an important component of therapy. Modifications include making dietary changes and reducing caffeine consumption (see Nutritional Considerations), as well as avoiding falls. Other important lifestyle changes include weight–bearing exercise at least 3 times a week and smoking cessation (see below for more information).

Medications used to decrease bone resorption include bisphosphonates, raloxifene, calcitonin, and estrogens. Teriparatide is  used to increase bone mass. All these medications must be given with adequate amounts of calcium and vitamin D.

Bisphosphonates (alendronate, pamidronate, risedronate, and ibandronate) decrease bone resorption and are useful for prevention and treatment.

Raloxifene, a selective estrogen receptor modulator (SERM), inhibits bone resorption and is useful for prevention. Like tamoxifen, it reduces the risk of breast cancer, but, unlike tamoxifen, it does not increase the risk of endometrial cancer.

Calcitonin decreases bone resorption and may help decrease associated pain.

Estrogen use, with or without progesterone, reduces bone resorption and slows progression of osteoporosis. However, the benefits of estrogens must be weighed against the many possible adverse effects of estrogen therapy, particularly the increased risk of breast cancer, cardiac events, and strokes.

Testosterone may increase bone mass for men with osteoporosis and low testosterone levels. However, the effect of testosterone on cancer risk should be considered. If it is used, prostate–specific antigen (PSA) level should be monitored.

Thiazides decrease renal calcium loss, and are associated with increased bone mass density. However, they may increase the risk for electrolyte disturbances and postural hypotension.

Teriparatide, a recombinant human parathyroid hormone, stimulates bone formation and is administered subcutaneously.

Exercise reduces osteoporosis risk. Expert reviews have confirmed that regular weight–bearing and resistance exercise is helpful for increasing the bone mineral density (BMD) of the spine in postmenopausal women and for treating osteoporosis.^4,5

Smoking cessation has been associated with decreased risk of hip fracture. Smoking has an independent, dose–dependent effect on bone loss, which increases fracture risk in both sexes. Smoking increases the lifetime risk of developing a hip fracture by an estimated 31% in women and 40% in men, and increases the lifetime risk for vertebral fracture by an estimated 13% in women and 32% in men. Risk declines among former smokers, but the benefit is not observed until 10 years after smoking cessation.^6,7