Osteoporosis: What about men?

With older women in the United States about 4 times more likely than their male counterparts to develop osteoporosis,^1,2 physicians often fail to screen for—or to treat—low bone mass in men. There are plenty of reasons why they should.

First and foremost: Osteoporosis is a leading cause of morbidity and mortality in the elderly.³ An estimated 8.8 million American men suffer from osteoporosis or osteopenia.³ And, although only about 20% of osteoporosis patients are male, men sustain between 30% and 40% of osteoporotic fractures.^1,2 What’s more, hip fracture in men has a mortality rate of up to 37.5%—2 to 3 times higher than that of women with hip fracture.^4,5

Clearly, then, it is crucial to be aware of the risks of osteoporosis faced by both men and women as they age. Here’s a look at what to consider, when to screen, and how to treat male patients who have, or are at risk for, osteoporosis.

Which men are at risk?

The incidence of fractures secondary to osteoporosis varies with race/ethnicity and geography. The highest rates worldwide occur in Scandinavia and among Caucasians in the United States; black, Asian, and Hispanic populations have the lowest rates.^6,7 As with women, the risk of osteoporotic fracture in men increases with age. However, the peak incidence of fracture occurs about 10 years later in men than in women, starting at about age 70.⁸ Approximately 13% of white men older than 50 years will experience at least one osteoporotic fracture.⁹

There are 2 main types of osteoporosis: primary and secondary. Up to 40% of osteoporosis in men is primary,⁴ with bone loss due either to age (senile osteoporosis) or to an unknown cause (idiopathic osteoporosis).¹⁰ For men 70 years or older, osteoporosis is assumed to be age related. Idiopathic osteoporosis is diagnosed only in men younger than 70 who have no obvious secondary cause.¹⁰ There are numerous secondary causes, however, and most men with bone loss have at least one.⁴

Common secondary causes: Lifestyle, medical conditions, and meds

The most common causes of secondary osteoporosis in men are exposure to glucocorticoids, primary or secondary hypogonadism (low testosterone), diabetes, alcohol abuse, smoking, gastrointestinal (GI) disease, hypercalciuria, low body weight (body mass index <20 kg/m2), and immobility (TABLE 1).^4,5,8,10

Chronic use of corticosteroids, often used to treat chronic obstructive pulmonary disease (COPD), asthma, and rheumatoid arthritis, directly affects the bone, decreasing skeletal muscle, increasing immobility, and reducing intestinal absorption of calcium as well as serum testosterone levels.¹⁰ Men with androgen deficiency (which may be due to androgen deprivation therapy to treat prostate cancer) or chronic use of opioids are also at increased risk.^4,5,10-12

Diagnostic screening and criteria

The World Health Organization has established diagnostic criteria for osteoporosis using bone mineral density (BMD), reported as both T-scores and Z-scores as measured on dual-energy x-ray absorptiometry (DEXA) scan.¹³ The T-score represents the number of standard deviations above or below the mean BMD for young adults, matched for sex and race, but not age. It classifies individuals into 3 categories: normal; low (osteopenia), with a T-score between -1 and -2.5; and osteoporosis (T-score ≤-2.5).^4,14 The Z-score indicates the number of standard deviations above or below the mean for age, as well as sex and race. A Z-score of ≤-2.0 is below the expected range, indicating an increased likelihood of a secondary form of osteoporosis.¹⁴

Which men to screen?

The US Preventive Services Task Force has concluded that evidence is insufficient to assess the balance of benefits and harms of screening for osteoporosis in men. It therefore makes no recommendation to screen men who don't have evidence of previous fractures or secondary causes of osteoporosis.¹⁵

Other organizations agree that there is insufficient evidence to recommend routine screening for men without known osteoporotic fractures or secondary causes for osteoporosis. There are, however, some guidelines that are useful in clinical practice.

The most common causes of secondary osteoporosis in men include exposure to glucocorticoids, primary or secondary hypogonadism, diabetes, alcohol abuse, and smoking.

The Endocrine Society, American College of Physicians (ACP), and National Osteoporosis Foundation (NOF) recommend screening men ages 70 years or older, and men ages 50 to 69 who have risk factors for fracture and/or a history of fracture sustained after age 50.^5,16,17 (See “Did you know?”)^{1,2,4,5,9-12,16,17} Prior to screening, it is important to do a complete medical history and physical examination.