From the Townsend Letter for Doctors & Patients
by Alan R. Gaby, MD
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Pancreatic enzymes block food allergy reactions
Ten patients (mean age, 43 years) with food allergy documented by double-blind, placebo-controlled food challenges underwent further double-blind food challenges through a nasogastric tube with a known offending food, with or without the addition of an enteric-coated pancreatic enzyme preparation (Panzytrat; 120,000 IE per challenge). Compared with no enzymes, administration of pancreatic enzymes markedly reduced the severity of food-induced symptoms in all 10 patients, and significantly blunted the rise in urinary methylhistamine excretion following the food challenge. Urinary histamine was not found to be of diagnostic value, either for monitoring allergic reactions or for assessing the effect of pancreatic enzymes.
Comment: These results suggest that administration of pancreatic enzymes reduces the severity of allergic reactions to foods. However, it is possible that some of the improvement (e.g., the intestinal symptoms) was due to an enhancement of digestive function, rather than to an anti-allergy mechanism. All 10 patients in the study suffered from postprandial abdominal symptoms, whereas fewer experienced allergic rhinoconjunctivitis (60%), skin reactions (50%), or asthma (20%). According to a personal communication from one of the authors (Raithel; May 26, 2002), extra-intestinal symptoms did improve, but to a lesser extent than intestinal symptoms. The foods that were challenged were not, in general, high-fat foods; this supports the anti-allergy mechanism, rather than the improved-digestion mechanism.
The dose of pancreatic enzymes used in this study (120,000 IE per challenge) was listed in units not familiar to American doctors. If any readers are able to convert this dose into units used in the US, please write to the Townsend Letter.
Raithel M, et al. Pancreatic enzymes: a new group of antiallergic drugs? Inflamm Res 2002;51(Suppl 1):S13-S14.
Melatonin lowers sperm counts
In a double-blind crossover study, eight healthy men (mean age, 23.4 years) received 3 mg/day of melatonin or a placebo during two separate three-month periods. The dose was taken each day between 5 and 6 p.m. During the melatonin phase, two men experienced a reduction in sperm concentration to 3 million/ml and 12 million/ml, respectively, and motility declined to 32% and 30%, respectively. These changes were associated with a decline in seminal plasma and serum 17-beta-estradiol levels and an increase in testosterone:17-beta-estradiol ratios. Six months after melatonin was discontinued, sperm concentration and motility had returned to normal in one of these men, but the other man still had abnormal values, and the testosterone:17-beta-estradiol ratio remained elevated. The two men whose sperm counts declined had pretreatment counts of approximately 25-35 million/ml, which were within the normal range, but considerably lower than those of the men whose sperm counts were not affected by melatonin.
Comment: The results of this preliminary study suggest that melatonin can decrease sperm counts and motility in some healthy young men, possibly by inhibiting the production of estrogen, which has been shown to play a role in male reproduction. It is possible that the observed changes represent random biological fluctuations that had nothing to do with taking melatonin; a larger study would be needed to investigate that possibility. It is not known whether short-term use of melatonin (for example, to prevent jet lag) would have a similar effect. Until further information is available, men interested in taking melatonin should consider this potential side effect.
Luboshitzky R, et al. Melatonin administration alters semen quality in healthy men. J Androl 2002;23:572-578.
Lactobacillus GG prevents cavities
Five hundred-ninety four children aged 1-6 years were randomly assigned to receive, in double-blind fashion, milk with added Lactobacillus GG (containing 5-10 x 105 colony-forming units per ml) or unsupplemented milk. After seven months, the incidence of dental caries was 49% lower in the Lactobacillus GG group than in the control group (p = 0.004). The beneficial effect of Lactobacillus GG was most pronounced in three- and four-year-old children. Treatment with Lactobacillus GG also reduced the counts of the cariogenic bacterium Streptococcus mutans.
Comment: Lactobacillus rhamnosus GG (also called Lactobacillus GG) is a strain of lactobacillus that was originally isolated from a human stool specimen. It appears to be a particularly useful probiotic agent, because it is resistant to digestive juices, can colonize the human intestine, and produces an antimicrobial substance. This organism has been found to be effective against Clostridium difficile diarrhea and other types of diarrhea, and may also be useful for the treatment of atopic dermatitis, Crohn's disease, and other conditions. The present study suggests that supplementation with this organism may prevent dental caries in children, possibly by reducing the concentration of cariogenic bacteria in the mouth.
Nase L, et al. Effect of long-term consumption of a probiotic bacterium, Lactobacillus rhamnosus GG, in milk on dental caries and caries risk in children. Caries Res 2001;35:412-420.
Herbal treatment for parasitic infection
Two hundred-four patients with schistosomiasis (a parasitic infection) were treated with a combination of resin and volatile oil of myrrh (from the stem of Commiphora molmol), at a dose of 10 mg per kg of body weight per day for three days. Patients who still showed living ova in colonic or rectal mucosal biopsy specimens two months after treatment were given a second course of 10 mg per kg per day for six days, and biopsy specimens were obtained again two months later. The cure rate from the first course of treatment was 91.7%. Re-treatment of patients who did not respond to the first course resulted in a cure rate of 76.5%, increasing the overall cure rate to 98.1%. The treatment was well tolerated; side effects were reported by 11.8% of the patients, but were mild and transient. Twenty patients provided biopsy specimens six months after treatment and none of those showed living ova.
Comment: Schistosomiasis affects more than 180 million people worldwide. Although early treatment usually produces good results, if not adequately treated it can lead to complications including renal failure, liver damage, heart failure, and seizures. Praziquantel is the drug of choice, but resistance to this drug can occur. The present study indicates that an extract of myrrh is a safe and effective treatment for this common parasitic infection.
Sheir Z, et al. A safe, effective, herbal antischistosomal therapy derived from myrrh. Am J Trop Med Hyg 2001;65:700-704.
Intravenous magnesium knocks out acute migraines
Thirty patients with moderate or severe migraine attacks were studied. The first 15 patients received, in single-blind fashion, 1 g of magnesium sulfate (Mg) intravenously over 15 minutes, and the next 15 patients received placebo (10 ml of 0.9% sodium chloride intravenously). Patients in the latter group who did not experience relief of pain, nausea and vomiting after 30 minutes were then treated with Mg. Immediately after treatment and at 30 minutes and two hours, 13 of 15 patients (86.6%) in the Mg group were pain-free, and the remaining two patients reported a reduction in pain severity. At all three time periods, accompanying symptoms (such as nausea, vomiting, photophobia, and irritability) had disappeared in each of the 14 patients who experienced them. None of the patients given Mg had a recurrence of pain within 24 hours. In the placebo group, no patient became pain-free (p < 0.001 for group difference) and only one (6.7%) experienced a reduction in pain. Accompanying symptoms disappeared in three patients (20%) 30 minutes after placebo administration (p < 0.0001 for group difference). When patients in the placebo group were given Mg, the response was similar to that in the Mg group. Mild side effects (such as a burning sensation in the face and neck, flushing, and/or a 5-10 mm Hg drop in systolic blood pressure) occurred in 86.6% of the patients given Mg. However, none of these side effects were serious, and no patient had to discontinue the treatment.
Comment: The results of this study are consistent with those of a previous report (Clin Sci 1995;89:633-6) demonstrating that intravenous magnesium can rapidly abort an acute migraine. Double-blind studies would be difficult, if not impossible, to perform, because intravenous magnesium produces obvious side effects (described above) in most patients. However, because of the dramatic benefits reported, this treatment deserves consideration as first-line therapy for migraine attacks. Most doctors charge $30-50 to administer intravenous magnesium (the magnesium itself costs only a few dollars); this compares favorably with the $50 or so for a single dose of self-administered subcutaneous sumatriptan (Imitrex®). However, intravenous magnesium is much safer than Imitrex, which has been linked on rare occasions with myocardial infarction, hypertensive crisis, and death.
Demirkaya S, et al. Efficacy of intravenous magnesium sulfate in the treatment of acute migraine attacks. Headache 2001;41:171-177.
Nutritional support before surgery prevents infections
Fifty patients scheduled to undergo cardiac surgery were randomly assigned to receive, in double-blind fashion, an enteral nutrition formula supplemented with L-arginine, omega-3 fatty acids, and yeast RNA (Oral Impact®, Novartis Nutrition, Bern, Switzerland), or an isocaloric control formula during the 5-10 days prior to surgery. Patients were included in the study if they were at least 70 years of age, had an ejection fraction of less than 40%, or were scheduled to undergo mitral valve replacement. Each patient consumed a minimum of 5 L and a maximum of 10 L of their assigned formula during the preoperative period. Compared with the control formula, the supplemented formula significantly improved several laboratory measures of immune function. In addition, the incidence of postoperative infections was 69% lower in the supplemented group than in the control group (17% vs. 55%; p = 0.01).
Comment: L-Arginine, omega-3 fatty acids, and RNA have each been shown to enhance immune function. The results of the present study suggest that adding these nutrients to an enteral formula can reduce the incidence of postoperative infections in elderly individuals undergoing cardiac surgery. Oral Impact also contains 27% more protein than the control formula used in this study, so it is possible that some of the observed benefit was due to an improvement in protein status. The specific contributions of L-arginine, omega-3 fatty acids, and RNA to the outcome should be investigated further, because Oral Impact is considerably more expensive than most commonly used enteral nutrition formulas.
Tepaske R, et al. Effect of preoperative oral immune-enhancing nutritional supplement on patients at high risk of infection after cardiac surgery: a randomised placebo-controlled trial. Lancet 2001;358:696-701.
Deception among participants in clinical trials
The incidence of intentional dumping of metered-dose inhalers (MDIs) during a clinical trial was assessed in 101 smokers enrolled in The Lung Health Study, a clinical trial to evaluate the effect of regular use of an inhaled bronchodilator on the progression of COPD. Each participant was given a prescribed medication schedule to follow. The participants were not informed that their medication use was being monitored by a Nebulizer Chronolog attached to the MDIs, which recorded the date and time of each MDI actuation. Thirty of the 101 participants (30%) actuated their inhalers more than 100 times within a three-hour period on at least one occasion during the first year of the trial. Only one of 135 other participants who had been informed of the monitoring capability of the nebulizer did so. Most of these dumping episodes occurred shortly before a clinic follow-up visit, suggesting an active attempt to hide noncompliance from the clinic staff.
Comment: These results suggest that participants in clinical trials frequently use deception to hide their non-compliance. Such deception would tend to make the treatment being studied appear less effective than it really is. Commonly used methods of assessing compliance, such as questionnaires and pill counts, would fail to detect noncompliance, as embarrassed participants would presumably lie or dump some of their pills. When the results of open trials conflict with those of placebo-controlled trials, one should not automatically assume it was all a placebo effect; perhaps the participants in the controlled trial were "out-liars."
Simmons MS, et al. Unpredictability of deception in compliance with physician-prescribed bronchodilator inhaler use in a clinical trial. Chest 2000;118:290-295.
Whole oats for a healthy heart
Eighty-eight patients being treated for hypertension were randomly assigned to consume two whole grain oat-based cereals or two refined grain wheat-based cereals per day for 12 weeks. The oats group received a daily serving of 60 g of Quaker Oatmeal and 77 g of Quaker Oat Squares. Seventy-three percent of the patients in the oats group and 42% of those in the control group were able to stop or reduce their antihypertensive medication by half (p < 0.05). Furthermore, among those whose medication was not reduced, systolic blood pressure fell significantly more and diastolic pressure fell nonsignificantly more in the oats group than in the control group. Compared with controls, the oats group showed significantly greater reductions in mean total cholesterol (-24.2 mg/dl), LDL cholesterol (-16.2 mg/dl) and plasma glucose (-15 mg/dl).
Comment: This study shows that a diet containing whole oats can improve blood pressure control, reduce the need for antihypertensive medication, and reduce blood lipid and glucose levels. Each of these actions would be expected to reduce the risk of cardiovascular disease. Previous studies have shown similar results. There is now strong evidence that including oats in a whole-foods diet could help prevent heart disease.
Pins JJ, et al. Do whole-grain oat cereals reduce the need for antihypertensive medications and improve blood pressure control? J Fam Pract 2002;51:353-359.
Omega-3 fatty acid for depression
Twenty patients (mean age, 53.4 years) with recurrent unipolar depression, with Hamilton Depression Rating Scale (HAM-D) scores of 18 or higher, were randomly assigned to receive, in double-blind fashion, the ethyl ester of eicosapentaenoic acid (E-EPA; 1 g twice daily) or placebo for 4 weeks. All patients were receiving maintenance antidepressant therapy. At the end of weeks 2, 3, and 4, E-EPA was significantly more effective than placebo (p < 0.001), as determined by HAM-D scores. The mean reduction in HAM-D score was 12.4 points in the E-EPA group, compared with 1.6 in the placebo group. 6 of 10 patients receiving E-EPA, compared with 1 of 10 patients receiving placebo, achieved a 50% reduction in HAM-D score. No significant side effects were seen. It is concluded that the ethyl ester of eicosapentaenoic acid either augments the effect of antidepressant medication or has independent antidepressant properties of its own.
Nemets B, et al. Addition of omega-3 fatty acid to maintenance medication treatment for recurrent unipolar depressive disorder. Am J Psychiatry 2002;159:477-479.
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