Highlights of this issue

CMAJ 2000;163(1):

• Preventive health care, 2000 update: screening and management of hyperhomocysteinemia for the prevention of coronary artery disease events [Research]
• Homocysteine: To screen and treat or to wait and see? [Commentary]

Does altered homocysteine metabolism play a role in the pathogenesis of cardiovascular disease, or is it simply a nonspecific marker of vitamin deficiency? Gillian Booth and Elaine Wang, with the Canadian Task Force on Preventive Health Care, have reviewed the evidence. Retrospective case–control studies revealed that patients with coronary artery disease (CAD) had significantly higher fasting plasma total homocysteine (tHcy) levels (adjusted odds ratio [OR] 1.2–10.9) and post-methionine load tHcy levels (adjusted OR 1.3–6.7) than patients without CAD. Prospective studies revealed a dose–response relation between tHcy levels and CAD events and mortality among patients with vascular disease; however, the association in healthy patients was less consistent. A meta-analysis showed that folic acid reduced tHcy levels by 25% on average in people with or without vascular disease. Although insufficient evidence was found to recommend the screening or management of hyperhomocysteinemia, the task force encourages adherence to the recommended daily allowance of folate and vitamins B₆ and B₁₂. In an accompanying commentary, Jacques Genest and colleagues discuss the treatment dilemmas as we await the results of at least 12 large studies underway in the United States, Canada and Europe.

• Sudden neck movement and cervical artery dissection [Commentary]

Over the past year the Canadian Stroke Consortium has prospectively collected detailed information on 74 cases of cervical artery dissection. The mean age of the patients in this series was 44 years. Most of the injuries (72%) involved the vertebrobasilar artery, and most of the cases (81%) were associated with sudden neck movements ranging from therapeutic neck manipulation to a vigorous game of volleyball.

• Emerging relations between infectious diseases and coronary artery disease and atherosclerosis [Review]

The link between infectious disease and atherosclerosis has existed for over a century. Postulated mechanisms range from direct invasion of the vessel wall to local release of endotoxin to the systemic activation of inflammatory modulators and procoagulants. The agents or conditions most studied are Chlamydia pneumoniae, cytomegalovirus, Helicobacter pylori and periodontitis. Ignatius Fong reviews the epidemiological, pathological and microbiological evidence and identifies a number of issues to be resolved before the empiric use of antibiotics for CAD is warranted.

• Expansion of gambling in Canada: implications for health and social policy [Review]

In 1985 the provinces were given exclusive control over gambling and legalized computer, video and slot devices. By 1997/98 Canadians were spending $6.8 billion annually on some form of government-run gambling activity, and the provinces were spending $14 million on services for people with gambling problems. David Korn comments on the dual role played by government in encouraging gambling and protecting the public interest. He discusses the economic impact of gambling, identifies vulnerable populations and offers a public health perspective on the health and social policy implications.

• Who wants to pay for health care? [Commentary]

What share of health care expenditures is being paid by the federal government? Raisa Deber clarifies this murky issue. In 1977 the federal government introduced Established Programs Financing (EPF), which provided unencumbered direct per capita funding to the provinces that was indexed to population growth, and reduced federal taxation allowing provinces to increase their tax rate. In 1984 the Mulroney government reduced the index, shrinking federal transfers. In 1996 the Chrétien government combined the EPF with the Canada Assistance Plan to create the Canada Health and Social Transfer; this allowed Ottawa to cut the total transfer again while retaining a "cash floor" transfer. Against this background Deber points to a certain paradox in the insistence of tax-cutting provinces' on restoring funds cut by federal government. Is this a return to targeted federal funds?

© 2000 Canadian Medical Association or its licensors