Primary and Secondary Osteoporosis in Men
There are two main types of osteoporosis: primary and secondary.In cases of primary osteoporosis, the condition is either caused by age-related bone loss (sometimes called senile osteoporosis) or the cause is unknown (idiopathic osteoporosis). The term idiopathic osteoporosis is used only for men less than 70 years old; in older men, age-related bone loss is assumed to be the cause.
At least half of men with osteoporosis have at least one (sometimes more than one) secondary cause.
In cases of secondary osteoporosis, the loss of bone mass is caused by certain lifestyle behaviors, diseases or medications.
Causes of Secondary Osteoporosis in Men
Glucocorticoid excess
Bone loss is a very common side effect of these drugs. In fact, exposure to glucocorticoids accounts for 16-18% of osteoporosis in men.The damage these drugs cause may be due to their direct effect on bone, muscle weakness or immobility, reduced intestinal absorption of calcium, a decrease in testosterone levels or, most likely, a combination of these factors.
Bone mass often decreases quickly and continuously with ongoing use of glucocorticoids, with most of the bone loss in the ribs and vertebrae. About one-third of patients have evidence of vertebral fractures after 5 to 10 years of treatment with glucocorticoids. The risk of hip fracture is increased nearly three-fold. Therefore, patients taking these medications should talk to their doctor about having a bone mineral density (BMD) test; men should also be tested to monitor testosterone levels, as glucocorticoids often reduce testosterone in the blood.
A treatment plan to minimize damage to bone during long-term glucocorticoid therapy may include:
Hypogonadism
Hypogonadism refers to abnormally low levels of sex hormones. It is well known that loss of estrogen causes osteoporosis in women. In men, reduced levels of the sex hormones may also cause osteoporosis. In fact, it is estimated that up to 30% of men with osteoporotic vertebral fractures have low testosterone levels. While it is natural for testosterone levels to decrease with age, there should not be a sudden drop in this hormone comparable to the drop in estrogen experienced by women at menopause. However, medications like steroids, cancer treatments (especially for prostate cancer), and many other factors can affect testosterone levels.Testosterone replacement therapy may be helpful in preventing or slowing bone loss. Its success depends on factors such as age and how long testosterone levels have been reduced. Also, it is not yet clear how long any beneficial effect of testosterone replacement will last; therefore, doctors will usually treat the osteoporosis directly, using medications approved for this purpose.
Recent research suggests that estrogen deficiency may be a cause of osteoporosis in men. For example, estrogen levels are low in men with hypogonadism and may play a part in bone loss. Osteoporosis has been found in some men who have rare disorders of estrogen action. Therefore, the role of estrogen in men is under active investigation.
Alcohol abuse
There is a wealth of evidence that alcohol abuse may decrease bone density and lead to an increase in fractures. Low bone mass is found in 25 to 50% of men who seek medical help for alcohol abuse. One early study found the bone mass of young alcoholic males to be comparable to that of elderly females.In cases where bone loss is linked to alcohol abuse, the first goal of treatment is, of course, to help the patient stop--or at least reduce--his consumption of alcohol.
