John T. Schousboe, MD, MS, Park Nicollet Osteoporosis Center, Park Nicollet Health Services, Division of Health Policy and Management, School of Public Health, University of Minnesota, Minneapolis, MN, USA.

Fractures related to osteoporosis are increasingly recognized as a serious public health problem among older men. As in women, bone densitometry has substantial utility to aid in the identification of older men at high risk of fracture and for whom fracture prevention therapies are indicated. This article briefly reviews the epidemiology of osteoporosis and associated fractures in men, the association of bone mineral density with fractures in men, indications for bone densitometry among older men, and the interpretation of bone mineral density test results in men.
Key words: osteoporosis, bone mineral density, densitometry, men, fractures.

By Age 70 Men Lose Bone Mass at the Same Rate as Women

Valerie Serre, PharmD, PhD

Aging of the population is associated with the rising incidence of age-related conditions such as osteoporosis. In the US, as many as 41 million people could develop osteoporosis by 2015. Osteoporosis is a progressive microarchitectural deterioration of bone tissue, which induces skeletal fragility predisposing bone to fracture. This disease is mostly known to affect postmenopausal women. Osteoporosis in men has sparked interest because of the worrisome finding that 20% of people with osteoporosis are men. Men reach peak bone mass in their late 20s. The decline in bone mass becomes apparent in men in their 40s and by the age of 70 both men and women display an identical rate of bone loss. If left untreated, osteoporosis brings about complications such as pain, decreased quality of life, dependence, and fractures. These fractures are located mainly at the hip, vertebral wedge and wrist and are often associated with mortality. The dollar cost of this silent epidemic is enormous (over 10 billion US dollars per year in the United States), and it is likely to increase exponentially in the near future.

A Fragile Future for Men

In one of the largest late-stage clinical programs ever conducted, the investigational pyridinyl bisphosphonate drug risedronate (Actonel) reduced the incidence of new vertebral fractures by up to 49 percent, and lowered the risk of osteoporosis related non-vertebral fractures by up to 39 percent. The results were presented at the annual meeting of the Endocrine Society.

Professor Richard Eastell, professor of bone metabolism at the University of Sheffield, UK, presented safety data from five clinical studies that enrolled a total of 5,226 post-menopausal women. The proportion of women reporting GI side effects was similar in the risedronate and placebo groups. Currently, risedronate is not available in Canada. For the full article see Nature 1999;397:315-23.

Lilia Malkin, BSc

A fracture is often the first clinical sign of osteoporosis (OP), the silent disease of skeletal fragility characterized by decreased bone mass and deterioration of bone tissue that results in an increased vulnerability to fractures.

The bone mineral density (BMD) criterion frequently used to define osteoporosis was set in 1994 by the World Health Organization (WHO) as more than 2.5 standard deviations below the "young adult mean." An estimated 1.4 million Canadians suffer from OP. In the population aged 50 and over, approximately one in four women and one in eight men are affected. The incidence of the disease increases with age: 70 percent of women have osteoporosis by the age of 80. Predictably, the fracture risk rises with age, with women at higher risk due to both more extensive bone loss and longer average life span. Osteoporotic fractures make a significant contribution to morbidity and mortality in the geriatric population. For instance, the mortality rates within one year of hip fracture are estimated at between 12 and 37 percent, while the average death rate in octogenarians is 2.6 percent per year.

Unfortunately, OP is often asymptomatic prior to the occurrence of a fragility fracture, a break that occurs in the absence of major trauma to the affected bone. The best predictor of fracture risk is low bone density.

Anna Liachenko, BSc, MSc

While non-pharmacological approaches are clearly beneficial for prevention of osteoporosis (OP), for many women these measures are not enough and a pharmacological treatment is required. Until early this decade, this meant one choice, hormone replacement therapy. Now, non-hormonal bisphosphonate treatments are also available. Both approaches are comparably efficient in preventing bone loss, at least on repeat bone mineral density testing. Some experts are also advocating slow-release fluoride, and combination therapy is also increasing. However, treatment choice is a complex decision which should only be made after careful consideration of the risks and benefits of each treatment, by the patient and her physician.

Before reviewing particular classes of drugs, physicians need to remember that all patients at risk for OP or with proven OP should be taking calcium and vitamin D in appropriate doses (see Fracture Prevention Part 1).