Mary Anne Cooper MSc, MD, FRCPC, Department of Medicine, University of Toronto; Lecturer, Sunnybrook and Women’s Health Sciences Centre, Toronto, ON.

Introduction
Gastroesophageal reflux disease (GERD), the abnormal reflux of gastric and duodenal contents into the esophagus, is common. Almost 50% of the North American population experience symptoms once a month and 10% have symptoms daily.¹ Patients most commonly complain of pyrosis and regurgitation, but other symptoms such as dysphagia, chest pain and nausea are not rare.¹ As well, respiratory tract symptoms such as cough, hoarseness and asthma may be attributable to GERD (Table 1).^1,2

Acid reflux into the esophagus is a normal physiologic event. It occurs after meals when the lower esophageal sphincter (LES) tone is reduced. The LES opens, creating a common cavity with the stomach. Because stomach pressures are higher than esophageal pressures, gastric contents reflux into the esophagus. Formal measurement with 24-hour pH monitoring indicates that the pH of the esophagus should be < 4 for < 4% of the time. Factors that increase acid contact time with the esophagus promote GERD.

Naveen Arya, MD, FRCP(C), Resident, Gastroenterology sub-specialty training program, Univerity of Toronto, Toronto, ON.
Peter G. Rossos, MD, FRCP(C), Staff Gastroenterologist, University Health Network; Program Director, Division of Gastroenterology, University of Toronto, Toronto, ON.

Introduction
With advancing age, the use of non-steroidal anti-inflammatory drugs (NSAIDs) for the treatment of arthritis, pain and headache increases. Although there are many benefits of NSAIDs for their analgesic and anti-inflammatory properties, there are also potential serious side effects. The side-effect profile includes dyspepsia, gastrointestinal mucosal ulceration and bleeding, cardiac dysfunction, renal toxicity and platelet dysfunction (Table 1). Chronic use of NSAIDs is associated with serious gastrointestinal (GI) toxicity, which severely restricts the use of these medications. In the United States, adverse events associated with NSAIDs result in 103,000 hospitalizations and 16,500 deaths per year.¹ In the United Kingdom, it is estimated that 1/2000 NSAID prescriptions lasting for two months will result in death.²

The average cost of both over-the-counter and prescription NSAID use in the United States is approximately $5-10 billion dollars (U.S.) per year.³ Despite significantly increased costs of therapy, newer COX-2 inhibitors are frequently prescribed in an effort to reduce complications.

Marisa Battistella, BScPhm, Pharm D, Education Coordinator & Hemodialysis Pharmacist, Pharmacy Department, University Health Network, Toronto, ON.
Shabbir M.H. Alibhai, MD, MSc, FRCP(C), Staff Physician, University Health Network, Toronto, ON.

Constipation is a common symptom in patients of all ages, but its occurrence is highest among persons 65 years of age or older.^1,2 Constipation has been shown to diminish both quality of life and feeling of well-being.^3-5 Although constipation can have many causes, it is most often functional or idiopathic.^5,6 Furthermore, constipation can lead to serious complications such as malnutrition, fecal impaction, fecal incontinence, colonic dilation and even perforation of the colon.⁷

Definition
Constipation has different meanings to patients and physicians. A patient's perception of constipation may include not only the objective observation of infrequent bowel movements but also subjective complaints of straining with defecation, incomplete evacuation, abdominal bloating or pain, hard or small stools or a need for digital manipulation to enable defecation. Because the definition of constipation can be subjective, an international committee has recommended an operational definition of chronic functional constipation in adults.

C.A. Fallone, MD, FRCP(C), Division of Gastroenterology, McGill University Health Centre, Montreal, QC.

Definition of Dyspepsia
Defining dyspepsia is a somewhat confusing endeavour mainly because the definition itself has varied somewhat over the last few decades. Moreover, the distinction between uninvestigated and investigated dyspepsia is not always clear. Clinically, dyspepsia symptoms must be distinguished from the lower gastrointestinal symptoms of irritable bowel syndrome. Furthermore, the term dyspepsia is often used synonymously for upper gastrointestinal symptoms, but because most experts feel that dyspepsia must be distinguished from gastroesophageal reflux disease (GERD), it does not represent all upper gastrointestinal symptoms.

The Rome II definition of dyspepsia is the most recent and widely accepted.¹ Dyspepsia is defined as a pain or discomfort centred in the upper abdomen. This epigastric discomfort can be associated with other gastrointestinal symptoms such as bloating, feeling full, nausea, early satiety and heartburn. It is important to note that burning sensation in the epigastrium is not heartburn. Rather, heartburn refers to a burning sensation that originates from the epigastric region and radiates up towards the neck. Heartburn alone is not considered dyspepsia according to this definition.

Christopher N. Andrews, MD, Gastroenterology Fellow, Faculty of Medicine, University of Calgary, Calgary, AB.
Eldon A. Shaffer, MD, FRCPC, Professor of Medicine, Division of Gastroenterology, Faculty of Medicine, University of Calgary, Calgary, AB.

Introduction
Diverticular disease of the colon (or diverticulosis) is an anatomical description of saccular outpouchings of mucosa through the wall of the colon. It is very common in the Western world, and its prevalence is rising. This paper will briefly review the epidemiology and pathophysiology of diverticular disease, followed by a focus on the diagnosis and management of the two most common complications of the disease: diverticulitis and diverticular bleeding.

Epidemiology
The true prevalence of diverticulosis is unknown, but autopsy reports suggest that up to half of patients over 60 years are affected.¹ The frequency increases with age and is much higher in developed societies in which fibre intake is lower. In the Western world, the most commonly affected site in the colon is the sigmoid colon, sometimes with more proximal involvement.² However, in Asian countries diverticulae tend to be right-sided (in the ascending colon) and fewer in number. The reason for this difference is unknown.

Pathophysiology
The colon is made up of circumferential and longitudinal (taenia coli) muscle layers, which act in unison to propel stool towards the rectum.

Supporting Research and Public Education in Digestive Disorders

Gary A. Levy, MD, FRCP, President, Canadian Digestive Health Foundation; Director, Multi Organ Transplant Program, Toronto General Hospital, University of Toronto, Toronto, ON.

The Burden of Digestive Disorders in Canada
Many are aware of the devastating impact that diseases such as cancer and heart disease have on Canadians. However, few might realize that digestive diseases constitute an even greater health and economic burden, and seriously impair quality of life.

Despite the staggering statistics (see sidebar), funding for education and research from provincial and federal agencies lags far behind the prevalence and burden of disease. As an example, from 1988-1998, successful government gastroenterology grants decreased from 76 to 53. The total dollar value for digestive disease research also decreased from $6 million to $4.4 million over the same period.

Introducing the Canadian Digestive Health Foundation
In 1991, the Canadian Digestive Health Foundation (CDHF; then the Canadian Digestive Disease Foundation) was formed by a small group of Canadian gastroenterologists interested in enhancing the profile of gastroenterology in Canada and generating a stable source of funds for research and education. In 1994, the Foundation became a charitable organization. Between 1995 and 2000, one to two grants in gastrointestinal research were awarded annually, funding seven young investigators who have since become key members of the Canadian GI research community. However, it was only in the last few years that the organization began to grow towards its full potential.

In 2001, renewed support allowed the Foundation to establish a National Office. The Canadian Association of Gastroenterology (CAG), a professional society of physicians, other health care professionals and basic scientists, fully endorsed the Foundation as its fundraising foundation. Strong ties with the Canadian Institutes of Health Research (CIHR) offered new research funding opportunities. With this revitalization, the organization became the Canadian Digestive Health Foundation and redefined its mandate.

In 2001/2002, the Foundation made great strides in the arenas of research and public education. A detailed listing of all CDHF-sponsored research can be found on the CDHF website.

Public Education and the CDHF
Last year the CDHF launched its website (www.cdhf.ca) as the primary means of providing education for patients and the public regarding digestive diseases. Among other resources, the site contains a growing library of information on various gastrointestinal problems, prepared by key Canadian medical experts specializing in the area. While contacts from patients have confirmed the usefulness of this information, patients clearly desire a forum to interact with medical specialists regarding their particular situation. To meet this need, the CDHF is pleased to introduce a new program coming in January 2003 called Ask a Specialist.

This program allows you and your patients to ask a Canadian gastrointestinal specialist a question about a particular digestive disorder or health issue, via e-mail, and receive an answer within seven days. Please join us for the first installment in the series, Ask a Specialist About Dyspepsia, beginning January 1, 2003 at www.cdhf.ca.

Jeff Silverman, MD, FRCPC, Fellow in Adult Hematology, University of Toronto, Toronto, ON.
William Geerts, MD, FRCPC, Consultant in Clinical Thromboembolism, Sunnybrook and Women's College Health Sciences Centre, University of Toronto, Toronto, ON.

Introduction
Thrombocytopenia, defined as a platelet count of less than 150 x 10⁹/L, is an important clinical problem most commonly encountered in hospitalized patients. Although the differential diagnosis is extensive (Table 1), it is essential to always consider heparin-induced thrombocytopenia (HIT) in patients with thrombocytopenia who are hospitalized or who have recently been in a hospital.^1,2

HIT is an adverse drug reaction induced by exposure to heparin that is followed by thrombocytopenia, platelet activation and a dramatic increase in thrombosis risk. Although it is one of the most common and serious drug reactions in hospitalized patients, HIT is frequently not recognized until a major thromboembolic complication has resulted. However, if diagnosed and treated promptly, the outcome is generally favourable. With the widespread use of heparin in the elderly, geriatric patients constitute the largest population at risk of developing HIT. Therefore, clinicians providing care for the elderly must be able to recognize and manage HIT effectively and efficiently.

K. Farcnik, MD, FRCP(C), Psychiatrist, Division of Geriatric Psychiatry, University of Toronto, Toronto, ON.
M. Persyko, PsyD, CPsych, Division of Geriatric Psychiatry, University of Toronto, Toronto, ON.

Significant work has been done in the treatment of Alzheimer disease (AD) since cholinesterase inhibitors (CI) were approved in Canada five years ago. This has led to a better understanding of these drugs in terms of their different properties, therapeutic efficacy and indications for switching, and their use has since been extended to the treatment of AD with vascular pathology. Other treatments for AD, such as estrogens and non-steroidal anti-inflammatory drugs (NSAIDs), have also been evaluated further, while newer treatments, including a vaccine for AD, are currently in development. Although research outcomes have not always been positive, a significant effort is being made to achieve greater impact in a disease that is becoming ever more prevalent.

Cholinesterase Inhibitors
Currently, the CIs are the only class of drugs that have been proven efficacious in the symptomatic treatment of AD.¹ There are two types of CIs: acetyl and butyryl. Butyrylcholinesterase levels in the brain increase with the progression of AD, whereas levels of the enzyme acetylcholinesterase decrease.² The CIs approved in Canada that have demonstrated efficacy as well as a favourable safety profile are donepezil, rivastigmine and galantamine.

Typical or atypical? It depends on your point of view

Dr. Clarfield is the Chief of Geriatrics, Soroka Hospital Centre, Professor, Faculty of Medicine, Ben Gurion University of the Negev, Beersheva, Israel, and Professor (Adjunct), Division of Geriatric Medicine, McGill University and Jewish General Hospital, Montreal, QC., Canada.

Mr. CL, an 84-year-old gentleman, had coped reasonably well with his Parkinson's disease for several years. One Saturday evening he began to act strangely: muttering to himself, wandering aimlessly throughout the house, and from time to time uncharacteristically swearing at his wife. Mrs. L was surprised and distressed by her husband's behaviour since he had never before acted in this manner.

That Saturday night was difficult for Mrs. L, but eventually Mr. L fell asleep. The next morning he seemed somewhat improved, but as the afternoon wore on he once more began to act in the bizarre manner of the previous day. Sunday night was a repeat of the previous night and Mr. L's elderly wife was exhausted and at her wits end by Monday morning.

On that afternoon, Mrs. L phoned her husband's neurologist. He prescribed thioridazine 25mg b.i.d. to be added to the usual regimen of carbidopa/levodopa. The physician hurriedly mentioned something about patients with Parkinson's disease eventually developing dementia. Though horrified by this grave news, Mrs. L dutifully complied, providing the medication, as prescribed, to her husband.

The Lung Association Helps Patients Learn to Manage COPD

Susan Lightstone, co-author of Every Breath I Take: A Guide to Living with COPD, and former Senior Advisor for the National Judicial Institute, Ottawa, ON.

Looking hopeful and gazing skyward, Lorraine LeBlanc is pictured on the front cover of The BreathWorks Plan, a 41-page educational guide about living with Chronic Obstructive Pulmonary Disease (COPD) written for those, like Ms. LeBlanc, who know they have the disease or those who suspect they might have it. The guide is plainly written and full of practical advice for COPD patients on how to work together with their doctors to manage their disease, and is also intended for use by the family, friends and caregivers of those with COPD.

The BreathWorks Plan is distributed free of charge and forms an integral part of The Lung Association's recently announced BreathWorks Program.