By Louis Kuritsky, MD
Helicobacter pylori Infection and the Development of Gastric Cancer
Knowledge that Helicobacter pylori (HP) is involved in the pathogenesis of gastrointestinal (GI) disorders began in the early 1980s. In addition to nonmalignant GI syndromes, such as peptic ulcer disease, the World Health Organization (among others) has recognized HP as a definite carcinogen for gastric cancer. Uemura and colleagues have performed a prospective study of a large population of patients (n = 1526) in Japan who underwent endoscopy and confirmatory testing for the presence of HP, including tissue biopsy. Patients were followed up with repeat endoscopy at 1 and 3 years later.
Eighty-five percent of patients were HP positive at baseline. Gastric cancer developed in 2.9% of HP- infected patients, but in none of the uninfected patients. Gastric cancer did not develop in any of the HP-positive patients who had undergone treatment to eradicate HP.
In their discussion of this information, Uemura et al point out that previous studies that demonstrated carcinoma in HP-negative individuals may have used tests more likely to be false-negative than the battery of diagnostic tests used in this study. HP infection appears to be related to gastric cancer; in the relatively short-term observation reported here (up to 3 years), HP treatment was associated with an absence of the occurrence of gastric cancer.
Uemura N, et al. N Engl J Med. 2001; 345:784-789.
Effects of Physical Activity Counseling in Primary Care
The benefits of physical activity on health and well-being outcomes are well documented and diverse. Patients have indicated that they would like to receive counsel from their clinician about exercise, but there are little data on the frequency, adequacy, and efficacy with which health professionals offer advice about physical activity.
This trial was sponsored by the National Heart, Lung, and Blood Institute (NHLBI) to ascertain which of 2 education and counseling interventions was superior, and compare 2 interventions with "usual care" in the community. To evaluate this, 874 patients were randomized to receive either advice (physicians advised patients to increase activity, select a long-term goal, and visit with a health educator for educational materials on physical activity); assistance (same intervention as advice plus behavioral counseling intervention and a single phone contact at 1 week); and counseling (same as advice and assistance, but including biweekly telephone counseling for 6 weeks, followed by monthly contact; weekly classes on obtaining and maintaining healthy lifestyles were also included).
For increasing cardiorespiratory fitness, men differed from women in their responses to tailored interventions. Women responded more favorably to assistance and counseling than advice, but there was no difference in response to any one method over another. This study suggests that specially designed programmatic interventions may enhance the ability of women to achieve cardiovascular fitness, though additional benefits in men (over simple advice) are not apparent.
The Writing Group for the Activity Counseling Trial Research Group. JAMA. 2001;286:677-687.
Patients at High Risk of Infection After Cardiac Surgery
Postoperative morbidity and mortality (PMM) is increased among the elderly and persons with impaired ventricular function. Some of this adverse event profile may be due to nutritional inadequacies; studies of nutritional supplements such as L-arginine (the immediate precursor to nitric oxide), omega-3 polyunsaturated fatty acids (PUFA), and dietary nucleotides (eg, yeast RNA) have shown some favorable effects in postsurgical settings.
L-arginine, PUFA, and yeast RNA have been combined into a single oral entity (Oral Impact, Novartis Nutrition). This supplement, or a placebo control of equal volume and caloric content, was administered to 50 patients undergoing cardiac surgery for 5-10 days preoperatively.
Patients who received the supplement had statistically fewer infections postoperatively (4 vs 12). Other surrogate markers of immune status (eg, delayed-type hypersensitivity response, interleukin 6 levels) were also more favorably affected in the active treatment group. The study was not powered to show a difference in length of hospital stay. There were no adverse effects attributable to the supplementation. Nutritional supplementation with Oral Impact may favorably affect postoperative outcomes in cardiac surgery patients.
Tepaske R, et al. Lancet. 2001;358: 696-701.
Dr. Kuritzky, Clinical Assistant Professor, University of Florida, Gainesville, is Associate Editor of Internal Medicine Alert.