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).

Sonya Lytwynec, RegN, BScN,
Michael Borrie, BSc, MB, ChB, FRCPC
Southwestern Ontario Regional Geriatric Program: Continence Outreach

Urge urinary incontinence is one of five types of incontinence.¹ The assessment and therapeutic interventions associated with urge incontinence will be reviewed in this third article of a five-part series on urinary incontinence. The first article in this series provided an overview of the prevalence, types and treatment of incontinence in the frail elderly; the second discussed stress urinary incontinence.

Urge incontinence is defined as the involuntary loss of urine associated with the urgency to void. It is the most common type of incontinence in those individuals over the age of 60. Several studies report that urge incontinence occurs predominantly in men (73.3%), followed by mixed incontinence (19.1%), and stress incontinence (7.6%). The prevalence of urge incontinence in women is reported at 22%, and mixed incontinence at 29%.² Older women often experience combined symptoms of stress and urge incontinence called mixed incontinence. Patients with urge incontinence often suffer severe emotional distress, social embarrassment and isolation.

The severity of urge incontinence symptoms vary from occasional urine losses on the way to the bathroom to sudden, uncontrollable "flooding" without warning.

Thomas Tsirakis, BA

Late Onset Schizophrenia (LOS) is a rare disorder with a prevalence rate of less than 1 percent within the general population. LOS applies to those individuals who develop schizophrenia after the age of 40. The existence of LOS as a disorder separate from schizophrenia has been wrought with controversy, due mostly to a lack of consensus between European and North American medical standards. The general lack of agreement between the world's medical communities, as well as the overlapping of clinical features between LOS and other psychiatric disorders, has often resulted in misdiagnosis and confusion. In North America, LOS was completely eliminated from the third revised edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IIIR) of the American Psychiatric Association after the release of DSM-IV in 1994, and is now classified utilizing the same criteria as schizophrenia. The European medical community, however, still considers it to be a separate, yet related entity, with its own distinct symptomatology, and continues to define it utilizing DSM-IIIR criteria.

SMH Alibhai, MD, FRCPC

As any physician knows, stroke is a common cause of morbidity and mortality in older patients. Strokes can be divided into three major aetiological groups--haemorrhagic, thromboembolic, and lacunar. Practically speaking, if neuroimaging does not show evidence of haemorrhage, physicians will generally treat patients who present with an acute stroke (or a transient ischaemic attack (TIA), for that matter) with either antiplatelet or anticoagulant therapy. For patients with a well-documented embolic source (e.g. atrial fibrillation), warfarin is the treatment of choice. For all other patients with non-haemorrhagic stroke, the treatment is traditionally antiplatelet therapy.

However, there are several options within antiplatelet therapy. The standard drug has been acetylsalicylic acid (ASA), or aspirin. At least four large randomized controlled trials revealed Ticlopidine to be slightly more effective in reducing the incidence of strokes and TIAs than aspirin, although it was more costly and more toxic.¹ However, a later meta-analysis of 145 studies suggested ticlopidine was probably as equally effective as aspirin.² Although newer antiplatelet agents are on the horizon (e.g.

Michelle Durkin, BSc

How to determine when people suffering from Alzheimer's disease and other dementias should stop operating a motor vehicle is a complex and controversial issue. The decision can affect the patient (by impairing independence and mobility), his or her family, and the safety of the general public. As a greater percentage of the population ages, the number of functionally impaired drivers only increases, further complicating the issue.

The Canadian Medical Association's Guide for Physicians in Determining Fitness to Drive (5th edition) states that physicians should monitor the driving competence of a patient with dementia. Until now this has been difficult because an appropriate and accurate evaluation tool has not been available. Physicians relied solely on their own judgement. Now, however, the research of Dr. Allen Dobbs of the University of Alberta may provide this needed, effective evaluation tool with the development of a computer-based test called the Competence Screen.

In an interview, Dr.

Shari Tyson, BSc, MSc

Contrary to popular belief, osteoporosis (OP) is not just an aging woman's ailment. About 8% of men can also expect to develop this disease. In fact, hip fractures in elderly men account for approximately one third of all hip fractures sustained due to OP. In addition, one third of those who have suffered such a fracture will not survive beyond a year. Yet despite the large numbers of men affected, and the millions of health care dollars allocated to the care of individuals with this disease, osteoporosis in men remains under-diagnosed, infrequently reported, and inadequately studied.

OP affects women to a greater extent than men. However, for several key reasons, men develop this disease at a much later age than women. For the first thirty years of life, the rate of bone formation exceeds the rate of resorption resulting in general bone growth and thickening. After peaking at age 30 for both sexes, the opposite is true; there is an increased rate of bone resorption and a general loss of bone mass. This rate is further accelerated in women when a dramatic decrease in estrogen production occurs at menopause.

Both estrogen and testosterone have been shown to play key roles in preventing the resorption process. The exact manner in which testosterone performs this function has yet to be discerned.

D'Arcy L. Little, MD
Chief Resident, Family Medicine, Sunnybrook Health Science Centre, North York, Ontario

Background

Angiotensin Converting Enzyme inhibitors (ACE inhibitors) interact with the body's renin-angiotensin-aldosterone axis. Angiotensinogen (alpha-2 globulin) is converted to angiotensin I or AG-I (inactive) by renin released by the kidney in response to renal ischemia, hypotension, hypovolemia or depletion of sodium ions. ACE inhibitors block the conversion of AG-I to AG-II. AG-II is a powerful vasoconstrictor, as well as a releaser of aldosterone (an adrenal cortical hormone that leads to sodium retention in the kidney), see Figure 1.

 

FIGURE 1

Despite the fact that elderly patients have lower levels of plasma renin than their younger counterparts, ACE inhibitors have been evolving as important agents in the treatment of several cardiovascular diseases in both younger and older patients.

Jocalyn P. Clark, MSc

A recent article published in a special issue of the Canadian Medical Association Journal on Diversity and Women's Health described poor inclusion and representation of women in clinical drug trials for treatment of myocardial infarction (MI). Despite heart disease being a leading cause of disability and death among North American women, especially older women, less than one-quarter of the patients included in the studies were women and the average age of participants was only 62 years. The work of Rochon and colleagues at the University of Toronto extends earlier findings of Gurwitz et al. at the University of Massachusetts who reviewed the literature for a 30 year period up to 1991 and found that women represented only 20% of MI drug trial participants. Most of these trials excluded patients over the age of 75 years. Traditionally, older people have been poorly represented in clinical trials because they are more difficult to study: they tend to have coexisting illnesses, they use other medications that may interact with study drugs, and the elderly are more vulnerable to adverse drug effects. Additional reasons for explaining women's exclusion include fear of harming a fetus, hormonal fluctuations that may complicate responses to medication, and the use of estrogens which may be protective for some diseases.