Bindslev-Jensen, C., D. Briggs, M. Osterballe, 2002. Can we determine a threshold level for allergenic foods by statistical analysis of published data in the literature? Allergy. 57: 741–746.
Background: The aim of this paper was to investigate whether a statistical model could be developed to estimate a ‘‘threshold’’ dose for foods eliciting allergic reactions in susceptible patients. The threshold dose is defined to be one that elicits allergic reactions in a given (small) proportion of susceptible patients, using data from published studies. Methods: Based on data available from the literature, we developed a statistical model using the actual allergen content in the four foods, where data for allergen content are available (peanut, soy, egg, milk). Results: The model demonstrated that the threshold doses giving a reaction of one in a million in susceptible patients were within the same order of magnitude for egg, milk and soy, but were an order of magnitude lower for peanut flour: 0.005 mg of cow’s milk, 0.002 mg of fresh hen’s egg, 0.0007 mg of peanut, or 0.0013 mg of soy flour. Conclusions: Although several assumptions were made in creating this statistical model, we demonstrated that the previously published differences in threshold doses for various foods can be largely eliminated by comparing actual allergen content; this may therefore serve as a model for further studies.
van Dam, R.M., E.B. Rimm, W.C. Willett, M.J. Stampfer, F.B. Hu, 2002. Dietary patterns and risk for type 2 diabetes mellitus in U.S. men. Ann Intern Med. 136:201-209.
Background: The role of diet in the development of type 2 diabetes mellitus remains unsettled. Objective: To examine the association between major dietary patterns and risk for type 2 diabetes mellitus. Design: Prospective cohort study. Setting: United States. Participants: 42 504 male health professionals, 40 to 75 years of age, without diagnosed diabetes, cardiovascular disease, or cancer at baseline. Measurements: Using factor analysis based on data from food frequency questionnaires, we identified and validated two major dietary patterns that we labeled “prudent” (characterized by higher consumption of vegetables, fruit, fish, poultry and whole grains) and “western” (characterized by higher consumption of red meat, processed meat, French fries, high-fat dairy products, refined grains, and sweets and desserts). Relative risks and 95% CIs were adjusted for potential confounders, including body mass index (BMI), physical activity, and cigarette smoking. Results: During 12 years of follow-up (466 508 person-years), we documented 1321 cases of type 2 diabetes. The prudent dietary pattern score was associated with a modestly lower risk for type 2 diabetes (relative risk for extreme quintiles, 0.84 [CI, 0.70 to 1.00]). In contrast, the western dietary pattern score was associated with an increased risk for type 2 diabetes (relative risk, 1.59 [CI, 1.32 to 1.93]; P < 0.001 for trend). A high score for the western dietary pattern combined with low physical activity (relative risk comparing extreme quintiles of dietary pattern score and physical activity, 1.96 [CI, 1.35 to 2.84]) or obesity (relative risk for BMI ≥30 kg/m2 vs. <25 kg/m2, 11.2 [CI, 8.07 to 15.6]) was associated with a particularly high risk for type 2 diabetes. Conclusion: Our findings suggest that a western dietary pattern is associated with a substantially increased risk for type 2 diabetes in men.
Singh, R.B., G. Dubnov, M.A. Niaz, S. Ghosh, R. Singh, S.S. Rastogi, O. Manor, D. Pella, E.M. Berry, 2002. Effect of an Indo-Mediterranean diet on progression of coronary artery disease in high-risk patients (Indo-Mediterranean Diet Heart Study): a randomized single-blind trial. Lancet. 360:1455-61.
BACKGROUND: The rapid emergence of coronary artery disease (CAD) in south Asian people is not explained by conventional risk factors. In view of cardioprotective effects of a Mediterranean style diet rich in alpha-linolenic acid, we assessed the benefits of this diet for patients at high risk of CAD. METHODS: We did a randomized, single-blind trial in 1000 patients with angina pectoris, myocardial infarction, or surrogate risk factors for CAD. 499 patients were allocated to a diet rich in whole grains, fruits, vegetables, walnuts, and almonds. 501 controls consumed a local diet similar to the step I National Cholesterol Education Program (NCEP) prudent diet. FINDINGS: The intervention group consumed more fruits, vegetables, legumes, walnuts, and almonds than did controls (573 g [SD 127] vs 231 g [19] per day p<0.001). The intervention group had an increased intake of whole grains and mustard or soy bean oil. The mean intake of alpha-linolenic acid was two-fold greater in the intervention group (1.8 g [SD 0.4] vs 0.8 g [0.2] per day, p<0.001). Total cardiac end points were significantly fewer in the intervention group than the controls (39 vs 76 events, p<0.001). Sudden cardiac deaths were also reduced (6 vs 16, p=0.015), as were non-fatal myocardial infarctions (21 vs 43, p<0.001). We noted a significant reduction in serum cholesterol concentration and other risk factors in both groups, but especially in the intervention diet group. In the treatment group, patients with pre-existing CAD had significantly greater benefits compared with such patients in the control group. INTERPRETATION: An Indo-Mediterranean diet that is rich in alpha-linolenic acid might be more effective in primary and secondary prevention of CAD than the conventional step I NCEP prudent diet.
Albert, C.M., M. Gaziano, W.C. Willett, J.E. Manson, 2002. Nut consumption and decreased risk of sudden cardiac death in the Physicians’ Health Study. Arch. Intern. Med. 162:1382.
Background: Dietary nut intake has been associated with a reduced risk of coronary heart disease mortality; however, the mechanism is unclear. Since components of nuts may have antiarrhythmic properties, part of the benefit may be due to a reduction in sudden cardiac death. – Methods: We prospectively assessed whether increasing frequency of nut consumption, as ascertained by an abbreviated food frequency questionnaire at 12 months of follow-up, was associated with a lower risk of sudden cardiac death and other coronary heart disease end points among 21454 male participants enrolled in the US Physicians’ Health Study. Participants were followed up for an average of 17 years. Results: Dietary nut intake was associated with a significantly reduced risk of sudden cardiac death after controlling for known cardiac risk factors and other dietary habits (P for trend, .01). Compared with men who rarely or never consumed nuts, those who consumed nuts 2 or more times per week had reduced risks of sudden cardiac death (relative risk, 0.53; 95% confidence interval, 0.30-0.92) and total coronary heart disease death (relative risk, 0.70; 95% confidence interval, 0.50-0.98). In contrast, nut intake was not associated with significantly reduced risks of non-sudden coronary heart disease death or nonfatal myocardial infarction. Conclusion: These prospective data in US male physicians suggest that the inverse association between nut consumption and total coronary heart disease death is primarily due to a reduction in the risk of sudden cardiac death.
Background: A voluntary registry of individuals with peanut and/or tree nut allergy was established in 1997 to learn more about these food allergies. Objective: The purpose of this study was to elucidate a variety of features of peanut and tree nut allergy among the first 5149 registry participants. Methods: The registry was established through use of a structured questionnaire distributed to all members of the Food Allergy and Anaphylaxis Network and to patients by allergists. Parental surrogates completed the forms for children under the age of 18 years. Results: Registrants were primarily children (89% of registrants were younger than 18 years of age; the median age was 5 years), reflecting the membership of the Network. Isolated peanut allergy was reported by 3482 registrants (68%), isolated tree nut allergy by 464 (9%), and allergy to both foods by 1203 (23%). Registrants were more likely to have been born in October, November, or December (odds ratio, 1.2; 95% CI, 1.18-1.23; P < .0001). The median age of reaction to peanut was 14 months, and the median age of reaction to tree nuts was 36 months; these represented the first known exposure for 74% and 68% of registrants, respectively. One half of the reactions involved more than 1 organ system, and more than 75% required treatment, frequently from medical personnel. Registrants with asthma were more likely than those without asthma to have severe reactions (33% vs 21%; P < .0001). In comparison with initial reactions, subsequent reactions due to accidental ingestion were more severe, more common outside the home, and more likely to be treated with epinephrine. Conclusions: Allergic reactions to peanut and tree nut are frequently severe, often occur on the first known exposure, and can become more severe over time.
Sicherer, S.H., T.J. Furlong, A. Muñoz-Furlong, A.W. Burks, H.A. Sampson, 2001. A voluntary registry for peanut and tree nut allergy: Characteristics of the first 5149 registrants. J Allergy Clin Immunol. 108:128-132.
Background: A voluntary registry of individuals with peanut and/or tree nut allergy was established in 1997 to learn more about these food allergies. Objective: The purpose of this study was to elucidate a variety of features of peanut and tree nut allergy among the first 5149 registry participants. Methods: The registry was established through use of a structured questionnaire distributed to all members of the Food Allergy and Anaphylaxis Network and to patients by allergists. Parental surrogates completed the forms for children under the age of 18 years. Results: Registrants were primarily children (89% of registrants were younger than 18 years of age; the median age was 5 years), reflecting the membership of the Network. Isolated peanut allergy was reported by 3482 registrants (68%), isolated tree nut allergy by 464 (9%), and allergy to both foods by 1203 (23%). Registrants were more likely to have been born in October, November, or December (odds ratio, 1.2; 95% CI, 1.18-1.23; P < .0001). The median age of reaction to peanut was 14 months, and the median age of reaction to tree nuts was 36 months; these represented the first known exposure for 74% and 68% of registrants, respectively. One half of the reactions involved more than 1 organ system, and more than 75% required treatment, frequently from medical personnel. Registrants with asthma were more likely than those without asthma to have severe reactions (33% vs 21%; P < .0001). In comparison with initial reactions, subsequent reactions due to accidental ingestion were more severe, more common outside the home, and more likely to be treated with epinephrine. Conclusions: Allergic reactions to peanut and tree nut are frequently severe, often occur on the first known exposure, and can become more severe over time.
S.H. Sicherer, 2001. Clinical implications of cross-reactive food allergens. J Allergy Clin Immunol. 108:881-890.
As a consequence of the general increase in allergic sensitization, the prevalence of hypersensitivity reactions to multiple foods that share homologous proteins has become a significant clinical problem. A variety of these allergens conserved among plants (eg, profilin and lipid transfer proteins) and animals (eg, tropomyosin and caseins) have been characterized. Although studies with molecular biologic techniques have elucidated the nature of these ubiquitous allergens, clinical studies have lagged behind. The physician is called on to determine the risk of reaction to related foods among legumes, tree nuts, fish, shellfish, cereal grains, mammalian and avian food products, and a variety of other plant-derived foods that may share proteins with pollens, latex, and each other. Clinical evaluations require a careful history, laboratory evaluation, and in some cases oral food challenges. The pitfalls in the evaluation of food allergy–unreliable histories and limitations in laboratory assessment primarily caused by false-positive skin prick test responses/RAST results are magnified when dealing with cross-reactive proteins. This review focuses on the clinical data regarding cross-reacting food allergens with the goal of providing a background for improved risk assessment and a framework on which to approach these difficult clinical questions.
Kanny, G., D.-A. Moneret-Vautrin, J. Flabbee, E. Beaudouin, M. Morisset, F. Thevenin, 2001. Population study of food allergy in France. J Allergy Clin Immunol. 108:133-140.
Background: Food allergy (FA) is an important health problem for which epidemiologic studies are needed. Objective: We performed an epidemiologic survey in France to determine the prevalence, clinical pictures, allergens, and risk factors of FA. Methods: This study was conducted on 33,110 persons who answered a questionnaire addressed to a representative sample of the French population on a scale of 1:1000 (44,000 subjects aged ≤60 years). One thousand one hundred twenty-nine persons with FA selected during phase 1 received a second questionnaire. Results: The reported prevalence of FA is 3.52%: 3.24% evolutionary FA; 0.12% asymptomatic cases thanks to eviction diets; and 0.17% cured FA. The subjects were characterized by overrepresentation of city dwellers (80% vs 76%), women (63% vs 50%), and health care personnel (11% vs 4%). Fifty seven percent (vs 17%) presented with atopic diseases (P < .01). FA was often persistent, lasting more than 7 years in 91% of the adults. The most frequent allergens were 14% Rosaceae, 9% vegetables, 8% milk, 8% crustaceans, 5% fruit cross-reacting with latex, 4% egg, 3% tree nuts, and 1% peanut. Sensitization to pollen was significantly correlated with angioedema, asthma, rhinitis, and fruit allergy (P < .01). FA was 4 times more frequent in patients with latex allergy. The main manifestations of FA were atopic dermatitis for subjects under 6 years of age, asthma for subjects between 4 and 6 years of age, and anaphylactic shock in adults over 30 years of age (P < .007). Shocks were correlated with alcohol or nonsteroidal anti-inflammatory drug intake (P < .01 and P < .04, respectively). Conclusion: The prevalence of FA is estimated at 3.24% (range, 3.04% to 3.44%) in France. This study emphasizes the increasing risk of FA in well-developed countries and draws attention to certain FA risk factors, such as the intake of drugs (nonsteroidal anti-inflammatory drugs, β-blockers, and angiotensin-converting enzyme inhibitors) or alcohol, intolerance of latex gloves, and socioprofessional status.
Furlong, T.J., J. DeSimone, S.H. Sicherer, 2001. Peanut and tree nut allergic reactions in restaurants and other food establishments. J Allergy Clin Immunol. 108:867-870.
Background: The clinical features of food-allergic reactions in restaurants and other food establishments have not been studied. Of the registrants in the United States Peanut and Tree Nut Allergy Registry (PAR), 13.7% have reported reactions associated with such establishments. Objective: The purpose of this study was to determine the features of allergic reactions to peanut and tree nut in restaurant foods and foods purchased at other private establishments (eg, ice cream shops and bakeries). Methods: Telephone interviews were conducted through use of a structured questionnaire. Subjects/parental surrogates were randomly selected from among the 706 PAR registrants who reported a reaction in a restaurant or other food establishment. Results: Details were obtained for 156 episodes (29 first-time reactions) from 129 subjects/parental surrogates. Most reactions were caused by peanut (67%) or tree nut (24%); for some reactions (9%), the cause was a combination of peanut and another nut or was unknown. Symptoms began at a median of 5 minutes after exposure and were severe in 27% of reactions. Overall, 86% of reactions were treated (antihistamines, 86%; epinephrine, 40%). Establishments commonly cited were Asian food restaurants (19%), ice cream shops (14%), and bakeries/doughnut shops (13%). Among meal courses, desserts were a common cause (43%). Of 106 registrants with previously diagnosed allergy who ordered food specifically for ingestion by the allergic individual, only 45% gave prior notification about the allergy to the establishment. For 83 (78%) of these 106 reactions, someone in the establishment knew that the food contained peanut or tree nut as an ingredient; in 50% of these incidents, the food item was “hidden” (in sauces, dressings, egg rolls, etc), visual identification being prevented. In 23 (22%) of the 106 cases, exposures were reported from contamination caused primarily by shared cooking/serving supplies. In the remaining 21 subjects with previously diagnosed allergy, reactions resulted from ingestion of food not intended for them, ingestion of food selected from buffet/food bars, or skin contact/inhalation (residual food on tables, 2; peanut shells covering floors, 2; being within 2 feet of the cooking of the food, 1). Conclusions: Restaurants and other food establishments pose a number of dangers for peanut- and tree nut–allergic individuals, particularly with respect to cross-contamination and unexpected ingredients in desserts and Asian food. Failure to establish a clear line of communication between patron and establishment is a frequent cause of errors.
Beyer, K., E. Morrow, X.M. Li, L. Bardina, G.A. Bannon, A.W. Burks, H.A. Sampson, 2001. Effects of cooking methods on peanut allergenicity. J Allergy Clin Immunol. 107:1077-1081.
Background: Allergy to peanut is a significant health problem. Interestingly, the prevalence of peanut allergy in China is much lower than that in the United States, despite a high rate of peanut consumption in China. In China, peanuts are commonly fried or boiled, whereas in the United States peanuts are typically dry roasted. Objective: The aim of this study was to examine whether the method of preparing peanuts could be a factor in the disparity of allergy prevalence between the 2 countries. Methods: Two varieties of peanuts grown in the United States were roasted, boiled, or fried. Proteins were analyzed by using SDS-PAGE and immunoblotting. Allergenicity was compared by using immunolabeling with sera from 8 patients with peanut allergy. Results: The protein fractions of both varieties of peanuts were altered to a similar degree by frying or boiling. Compared with roasted peanuts, the relative amount of Ara h 1 was reduced in the fried and boiled preparations, resulting in a significant reduction of IgE-binding intensity. In addition, there was significantly less IgE binding to Ara h 2 and Ara h 3 in fried and boiled peanuts compared with that in roasted peanuts, even though the protein amounts were similar in all 3 preparations. Conclusion: The methods of frying or boiling peanuts, as practiced in China, appear to reduce the allergenicity of peanuts compared with the method of dry roasting practiced widely in the United States. Roasting uses higher temperatures that apparently increase the allergenic property of peanut proteins and may help explain the difference in prevalence of peanut allergy observed in the 2 countries.
