High Blood Pressure Study Backs Older Drug

As many as 85,000 deaths worldwide--half of them in the United States--may occur because physicians use calcium channel blockers to treat high blood pressure rather than cheaper diuretics, according to an analysis of several previous studies.

An estimated 28 million people--12.7 million of them in the United States--now take the drugs. North Carolina researchers reported Aug. 28 that patients using the calcium channel blockers had a 27% higher risk of heart attack and a 26% higher risk of heart failure.

The study shows that older and cheaper drugs are sometimes better than newer, more expensive ones.

Dr. Curt D. Furburg and his colleagues at the Wake Forest University School of Medicine combined the results of nine large studies comparing calcium channel blockers to other blood pressure drugs. Those studies enrolled more than 27,000 people. He reported his findings at a meeting of the European Cardiology Society in Amsterdam.

The drugs in question are calcium channel blockers, a family of drugs that includes Adalat, Calan, Cardene, Cardizem, Covera, Dilacor, Isoptin, Nimotop, Norvasc, Plendil, Procardia, Sular, Tiazac, Vasco and Verelan.

Furburg cautioned patients against stopping use of the drugs abruptly and did not call for them to be removed from the market. Instead, he stressed, physicians should be more cautious in prescribing them, and diuretics and other drugs should be the first line of therapy for high blood pressure. Patients should consult their physicians if they are concerned, he said. The National Heart, Lung and Blood Institute has a large study of calcium channel blockers underway, but results are not expected until 2002.

Beta-Blockers Useful in Severe Cases, Team Says

There was better news from the same meeting about another family of heart drugs called beta-blockers, which are widely used to treat patients with mild to moderate heart failure.

Despite their common use, physicians have been reluctant to prescribe them for people with severe heart failure because the drugs depress the heart rate and cardiologists feared that would create problems for people whose hearts were already badly damaged. The new study demonstrated, however, that the drugs are just as effective in this group of patients as in patients with milder heart failure.

Dr. Milton Packer and his colleagues at the Columbia University College of Physicians and Surgeons studied 2,289 people who had severe heart failure but did not require treatment in a hospital intensive care unit. In addition to medications they were already taking, half the patients received the beta-blocker Coreg (carvedilol) and half received a placebo.

After 30 months of treatment, Packer told the Amsterdam meeting on Tuesday, 35% fewer patients had died in the group receiving Coreg. The trial was halted in March, more than a year early, because the benefits were so substantial.

Report Touts Gene Therapy for Vessels

Boston researchers have reported what they call the first objective evidence that gene therapy to promote the growth of new blood vessels can improve the health of victims of heart disease.

Previous studies have claimed to produce improvements in pain and mobility in heart attack victims and patients with circulatory problems in their legs. Critics of these previous studies have contended that there was no evidence that new blood vessels were actually formed as the result of treatment.

Dr. Jeffrey M. Isner and his colleagues at the Tufts University School of Medicine studied eight men and five women who had suffered at least one heart attack, had severe chest pain (angina) and had undergone bypass surgery. In the new study, however, each patient underwent a special imaging technique called electromechanical mapping to determine which areas of the heart had an inadequate blood supply. Another test, called single-photon emission computed tomography, also revealed heart tissue that was starved for blood and thus not functioning.

The patients then received injections of so-called naked DNA containing the gene for a protein called vascular endothelial growth factor.. The hope was that the gene would be taken up by heart cells, leading to the production of the growth factor, which stimulates the growth of new blood vessels.

Isner’s team reports in the September Circulation: Journal of the American Heart Assn. (https://www.ahajournals.org) that six months after the treatment, the average number of angina attacks had dropped from 48 a week to only two. Average use of nitroglycerine tablets to fight pain dropped from 55 a week to two. Moreover, repeat imaging tests showed increased blood flow through the heart and partial or complete restoration of function in areas of oxygen-starved tissue.

St. John’s Wort Tested Against Antidepressant

St. John’s wort is as effective for treating mild depression as one of the most commonly used antidepressants and has fewer side effects, according to German researchers. The herb, whose active ingredient is hypericum, is widely used in Europe for treating depression and is gaining popularity in the United States. The results of previous clinical trials have been criticized for scientifically unsound research methods. Dr. Helmut Woelk of Universitat Giessen designed the new study to overcome those objections.

Woelk and his colleagues enrolled more than 300 patients with mild to moderate depression who were randomly treated for six weeks with either hypericum or the antidepressant imipramine (Tofranil). They reported in the Sept. 2 British Medical Journal (https://www.bmj.com) that the two drugs were “therapeutically equivalent,” as measured by standard rating scales for depression. Side effects, such as dry mouth, sweating and dizziness, were reported by only 39% of those taking hypericum, contrasted with 63% of those taking imipramine. Only 3% of those receiving hypericum stopped taking it, contrasted with 16% of those on imipramine. In view of its superior safety record, they concluded, St. John’s wort should be considered for first treatment of mild to moderate depression.

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Medical writer Thomas H. Maugh II can be reached at thomas.maugh@latimes.com.