An Aging Population will Lead to Mounting Fall-Related Health-Care Costs

Brian E. Maki, PhD, PEng
Professor, Department of Surgery and Institute of Medical Science,
University of Toronto; and Senior Scientist,
Sunnybrook and Women's College Health Sciences Centre

It is well established that falling is a common occurrence in persons aged 65 and older. Among those living independently, 30-60% will fall one or more times each year,^1-3 and the falling rate is even higher among those living in long-term or acute-care institutions.^4,5 Although the degree to which the falling rate among older adults differs from that among younger adults has not been well established, it is clear that falls in older persons are much more likely to result in serious physical and psychosocial consequences. The first part of this two-part article dealt with the fear of falling and other psychosocial correlates of falls, which has tended to be an under appreciated aspect of the problem. The now forthcoming second part, will focus on what has, historically, received the most attention-the physical consequences of falls.

Although the majority of falls do not result in serious physical injury, the societal costs associated with fall-related injuries are immense. Falls are, in fact, the leading cause of fatal injuries among seniors, accounting for twice as many deaths in this population as motor vehicle accidents.

D'Arcy L. Little, MD, CCFP
Director of Medical Education
York Community Services, Toronto, ON

Introduction
Influenza, an acute respiratory illness, causes more adults to seek medical attention than any other respiratory infection. In Canada, influenza is a seasonal disease, causing annual epidemics that affect 10-20 percent of the population and result in approximately 4,000 deaths, 70,000 hospitalizations, and 1.5 million days of lost work.¹ The elderly (people aged 65 years and older), and those with chronic cardiopulmonary disorders, diabetes and other metabolic diseases, have an increased risk of developing influenza complications. Hospitalization rates among elderly patients increase markedly during major influenza epidemics, and 90% of the deaths attributed to influenza and pneumonia are observed in this population.²

Vaccination remains the most reliable means of preventing an influenza infection and the resultant morbidity and mortality. Despite the significance of influenza, efforts to vaccinate the elderly remain suboptimal. A large study conducted in the Netherlands revealed that healthy elderly people avoid influenza vaccination because they fear the side effects, and because they believe that their general health is good and that the benefits of vaccination are, therefore, minimal.

An 'Achilles Heel' in Viral Replication Helps Researchers Develop a Universal Cure for Influenza

Nadège Chéry, PhD

When influenza attacks, it may infect anyone, regardless of his or her age. But when influenza kills, it usually takes the lives of individuals, like the elderly, who are less able to fight back.² In Canada, 6000 deaths are attributable to influenza every year³ with the highest rate of mortality occurring among people over 65 years of age.² Thus, when it comes to older individuals, both early diagnosis, and prevention are imperative. Because the influenza virus continuously changes, strategies for the prevention of flu outbreaks, although thoughtfully planned, have had limited success. Recently, however, scientists have found a "weakness" in influenza's ability to escape traditional flu therapies. This discovery has set the stage for the design of new antiviral drugs which, potentially, may constitute a cure for the flu.

What is Influenza?
Influenza is a member of the Orthomyxoviridae family,1 and causes disease by infecting the epithelial cells that compose the lining of the respiratory tract. Influenza produces symptoms similar to other viruses which infect the respiratory tract. Flu outbreaks are common among elderly persons, particularly in nursing homes.⁴ Since the immune systems of elderly people in a nursing home may be compromised,⁵ their ability to fight an influenza infection can be severely undermined.

Physiologic Vs. Ventricular Pacing--Which is More Appropriate for Your Elderly Patient?

Tawfic Nessim Abu-Zahra, BSc, MSc

Cardiac pacemakers are widely used to treat the symptoms of cerebral hypoperfusion and hemodynamic decompen-sation that are caused by bradycardia.¹ Pacemaker implantation is indicated for diseases of the sino-atrial (SA or sinus) and the atrioventricular (AV) nodes. There are two different modes of cardiac pacing, ventricular and physiologic. Ventricular pacing involves the direct stimulation of the ventricular myocardium without interaction with the atria, whereas physiologic pacing stimulates either the atria alone (atrial pacing) or both the atria and ventricles together (dual pacing).

There are many theoretical reasons why physiologic pacing should be superior to ventricular pacing. Physiologic pacing maintains the synchrony of atrial and ventricular contraction and the dominance of the sinus node by stimulating both the atria and ventricles.² Physiologic pacing may prevent the pacemaker syndrome--a collection of symptoms associated with the asynchronous contraction of the heart that occurs with ventricular pacing.² In comparison to ventricular pacemakers, however, physiologic pacemakers are more expensive, and are more difficult to monitor.³

Despite the theoretical advantages of physiologic pacemakers, this mode of pacing is not widely used.

Doctor Beware! A Patient's Retained Licence Can Cause the Loss of Yours

Tracey Tremayne-Lloyd and Lonny J. Rosen
Tremayne-Lloyd Partners
Toronto, Ontario

Physicians who treat elderly patients are well aware of how important a driver's licence is to a geriatric patient. The ability to drive represents perhaps the greatest source of independence to an elderly patient. The driver's licence ensures that he can maintain an active lifestyle, keeps up his social interaction and family ties, and that he has the ability to seek support or treatment for his ailments. All of these support systems are crucial to the health and wellbeing of an elderly patient, particularly as his health begins to fail. For this reason, it is particularly difficult for a family physician to contact her local Ministry of Transportation office and report that a patient has become medically unfit to drive. However, in most Canadian provinces, it is the physician's legal obligation to report any patient who has become unfit to drive, even when that report will result in the patient losing his driver's licence and all of its attendant benefits (especially the patient's independence). It is important to remember that while it is the Ministry, and not you the doctor, who will determine whether a patient's licence should be revoked, it is your licence to practice that may be jeopardized if you fail to make the required report.

Michael A. Gardam MSc, MD, CM, FRCPC
Medical Director, Tuberculosis Clinic
Associate Hospital Epidemiologist
University Health Network

What is a Skin Test and How is it Administered?
Tuberculin skin testing is the most established method of diagnosing tuberculosis infection, that is both active disease and asymptomatic latent infection. Different skin testing techniques have been developed over the past 70 years. The Mantoux test, however, is the standard procedure in North America. The Mantoux test involves the intradermal injection of 0.1 ml of purified protein derivative (PPD--a precipitate prepared from filtered heat-sterilized cultures of Mycobacterium tuberculosis). The only absolute contraindication to administering the test is a history of anaphylaxis induced by any of the components. Those with a history of BCG vaccination may be skin tested.

The test is usually administered in an area that is free of blood vessels, hair or edema, on the flexor surface of the forearm, but it may also be administered on the upper chest or back. The needle should be inserted just under the skin with the bevel facing up until the bevel is fully inserted. A bleb should be raised when the PPD is injected. If this is not accomplished, or the PPD leaks out onto the skin, the test should be readministered in a different site. The test must be read at 48 to 72 hours by a trained healthcare professional.

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

Gradual Immunologic Decline Explains Frequency of Herpes Zoster Among the Elderly

John M Conly, MD,CCFP, FRCPC, FACP
Consultant, Infectious Diseases
Director, Infection Prevention and Control
University Health Network (Toronto General,
Toronto Western and Princess Margaret Hospitals)
Professor of Medicine, University of Toronto

Introduction
Although it is now understood that varicella-zoster virus (VZV) is the etiologic agent for both varicella and herpes zoster, it is of historical interest to note that in the early medical literature, the clinical illnesses of varicella and herpes zoster were considered separate entities. Just six decades ago it was still taught at Harvard University that these viruses were unrelated.¹ In 1943, a pediatrician named Garland suggested that zoster may be due to the reactivation of a latent varicella virus,2 but it was not until 1958 that VZV was definitively recognized as the etiologic agent for both varicella and zoster.^3,4 The VZ virus is a DNA virus and is a member of the Herpesviridae family bearing many distinct similarities to other members of this group of viruses. The virus is spread by direct contact, by droplet and airborne routes from vesicular fluid of skin lesions, or from secretions from the respiratory tract.⁵ Transplacental transmission has also been documented.

Vaccination Curtails Influenza Outbreaks, but Side Effects are Still Possible

Dr. Allison McGeer MSc, MD FRCPC
Director,
Infectious Control,
Mount Sinai Hospital,
Toronto, ON

Every year, approximately one in six Canadians are infected with influenza. Healthy adults infected with influenza miss, on average, 2-7 days of work, and have a 10-30% chance of being prescribed a course of antibiotics. Influenza causes approximately 20% of all cases of acute otitis media in children,¹ and is the most common single infectious cause of hospital admission in young children.^2-4 However, the greatest impact of influenza is seen in the elderly. Every year, nearly 1% of older adults with any chronic underlying illness require hospital admission due to influenza, and about 4000 die from influenza and its complications.⁵

Vaccination is the only effective method for the prevention of influenza. Annual vaccination is required because influenza viruses are able to mutate their antigenic coat continuously in order to evade the human immune system (see "Chasing Away the Flu Bug" on page 20 for a more detailed description of this process).

The Elderly Display a Weaker Vaccine-Triggered Immune Response

Janet E. McElhaney, MD
Associate Professor, Division of Geriatrics,
Glennan Center for Geriatrics and Gerontology

Introduction
Pneumonia and influenza together have been identified as a leading cause of catastrophic disability and the fourth leading cause of death in the age 65 and over population. The fact that older people have an increased risk of contracting influenza and/or pneumococcal disease is to a large extent due to the combination of immuno-senescence and chronic diseases affecting 80 to 90% of the over 65 population. The aging process results in a decline in immunity that largely affects T-cell-mediated defense mechanisms. In older people, this decline is associated with an increased risk of viral infections, particularly influenza. Humoral immunity may also diminish with aging but to a lesser degree, perhaps due to the T-cell function that regulates the production of antibodies. Due to their ability to stimulate the aging immune system, influenza and pneumococcal vaccinations are by far the most cost-effective medical interventions when it comes to older adults.

Impact of Influenza and Pneumococcal Infections
The association between advanced age and the risk of serious influenza infections is one of the most well-documented examples of the potential effects of immunosenescence.