J. George Fodor, MD, PhD, FRCPC, FAHA, Professor of Medicine, Head of Research, University of Ottawa Heart Institute Prevention and Rehabilitation Centre, Ottawa, ON.

It is worthwhile to review the issue of hypertension in the elderly not only because it will become an ever-increasing problem with our aging population, but also because of the robust database currently at our disposal concerning improved risk assessment and efficacious therapy.

The Epidemiology
Generally, the elderly are considered those above 65 years of age. Dealing with hypertension in this age group, we quickly realize that this disease is a major epidemic with far-reaching consequences for both the health status of this segment of the population as well as our health care system.

The Canadian Heart Health Survey ascertained that among people in the age group 65-74 years, 56% of males and 58% of females were hypertensive.¹ This survey defined hypertension as systolic blood pressure (SBP) > 140mmHg or diastolic blood pressure (DBP) > 90mmHg, or current treatment with a prescription antihypertension medication or non-pharmacological treatment of blood pressure (weight control or sodium/salt restriction). The problem of hypertension in the elderly will continue to increase steadily in importance.

Anne-Sophie Rigaud, Hôpital Broca, CHU Cochin-Port-Royal, Paris, France.
Bernard Forette, Centre Claude Bernard de Gérontologie, Hôpital Sainte Périne, Paris, France.

Abstract
Diastolic blood pressure is considered an important risk factor for the development of cerebrovascular disease, congestive heart failure and coronary heart disease. However, it is now clear that isolated systolic hypertension and elevated pulse pressure play an important role in the development of these diseases, which are the major causes of cardiovascular morbidity and mortality among subjects aged 65 years and older. The benefit of antihypertensive therapy in reducing the incidence of cardiovascular and cerebrovascular complications has been shown for systolic and systolo-diastolic hypertension in all age groups. Because of the higher risk of cardiovascular disease in the elderly, the effect of antihypertensive treatment appears greater in patients over 60 or 65 years when expressed as an absolute risk reduction.

Definition
Essential (i.e. primary) hypertension is the main cause of hypertension in the elderly population. However, secondary, especially renovascular hypertension is more common in older than in younger adults. The incidence of hypertension in the elderly is high. In an ambulatory population aged 65-74, the overall prevalence is 49.6 % for stage 1 hypertension (140-159/90-99 mmHg), 18.2% for stage 2 (160-179/100-109 mmHg), and 6.

Chris MacKnight, MD, MSc, FRCPC
Division of Geriatric Medicine,
Dalhousie University,
Halifax, NS.

Dementia and hypertension are two of the most common conditions affecting older adults. A number of recent studies suggest that dementia is one of the long-term complications of hypertension. Studies also suggest that the treatment of hypertension may prevent dementia. This brief review will focus on the relationship between hypertension and dementia in older adults.

Epidemiology of Dementia
Eight percent of Canadians who are over the age of 65 suffer from dementia, with Alzheimer's disease being the most common cause (approximately 60% of cases).¹ Dementia is age-related, with the prevalence increasing from 2.4% of those from 65-74 years of age, to 34.5% of those 85 and older. Sixty thousand new cases occur each year in Canada.² The cost of providing care to these patients is substantial, at 3.9 billion dollars/year, in 1991 dollars.³ Vascular dementia is the second most common cause of dementia in Canada, accounting for 20% of cases. When discussing vascular dementia, it is important to recognize that the classic pattern of multiple infarcts is found only in approximately 1/3 of the cases. The other cases consist of patients who have changes in their white matter (likely on the basis of small vessel ischemia) with or without lacunar infarcts, or, rarely, single strategic strokes.