A recent story on NPR accused the drug manufacturer Merck of inventing a disease, osteopenia, in order to sell its drug Fosamax. It showed how the definition of what constitutes a disease evolves, and the role that drug companies can play in that evolution.
Osteoporosis is a reduction in bone mineral density that leads to fractures. The most serious are hip fractures, which require surgery, have complications like blood clots, and carry a high mortality. Many of those who survive never walk again. Vertebral fractures are common in the osteoporotic elderly and are responsible for dowager’s hump and loss of height. There is also an increased risk of wrist and rib fractures.
Bone density tends to decrease with age. Postmenopausal women are particularly susceptible to osteoporosis when their production of estrogen declines. The risk is increased in people taking corticosteroids and in people with certain diseases like rheumatoid arthritis. Other risk factors are European or Asian ancestry, smoking, excess alcohol, a family history of fractures, vitamin D deficiency, too much or too little exercise, malnutrition, and low body weight.
When a measurement like bone density varies widely in a population and decreases with age, how can we decide where to draw the line and call it abnormal? When does it become a disease requiring treatment? (more…)