PREVALENCE OF CONGENITAL HEART DISEASE IN THE POST-FORTIFICATION ERA
Ionescu-Ittu R, Marelli AJ, Mackie AS, and Pilote L. Prevalence of severe congenital heart disease after folic acid fortification of grain products: time trend analysis in Quebec, Canada. BMJ. 2009. doi: 10.1136/bmj.b1673.
Mandatory folic acid fortification of the food supply in the United States and Canada began in 1998 and was intended to reduce the rates of neural tube defects in newborns. Since the beginning of fortification, an increase in the concentrations of folate levels in women and a decrease in the prevalence of neural tube defects were observed. More recent research indicates that folic acid may play a role in reducing the prevalence of congenital heart malformations. The present population-based analysis examined the prevalence of congenital heart defects pre- and post-fortification in Quebec, Canada.
Data on infants born between 1990 and 2005 were extracted from Quebec medical administrative databases. Data were dichotomized into pre- and post-fortification time points. Of the 1.3 million infants born during the entire survey period, 2083 were born with severe congenital heart defects. When rates of heart defects were analyzed according to pre- or post-fortification time points, there was relatively little change in the incidence of heart malformations in the 9 years preceding folic acid fortification. In the 7 years following fortification, however, there was a 6% decrease per year in the rate of congenital heart defects. The authors argue that this post-fortification decrease, in combination with stagnant rates pre-fortification, support the notion that folic acid fortification is protective against the development of congenital heart malformations.
Comment: Drs. Gardiner and Fouron question whether folic acid fortification is an effective strategy for preventing congenital malformations. It has been observed that many women still have suboptimal blood folate levels in the post-fortification era, and in the above study it is not possible to determine the folate status of the mothers or the offspring. Given that rates of congenital heart disease vary year by year and the existing potential for gene-nutrient-environment interactions in congenital malformations, it is difficult to ascribe causality to intake of folic acid alone. Finally, since emerging research suggests that folic acid fortification may not have universally beneficial effects, and in some cases may be related to harmful outcomes, Gardiner and Fouron propose a search for more effective interventions targeting women in their childbearing years is required.
Comment: Gardiner HM and Fouron JC. Folic acid fortification and congenital heart disease. BMJ. 2009. doi: 10.1136/bmj.b1144.
CAROTENOID INTAKE AND METABOLIC SYNDROME IN OLDER MEN
Sluijs I, Beulens JW, Grobbee DE, and van der Schouw YT. Dietary carotenoid intake is associated with lower prevalence of metabolic syndrome in middle-aged and elderly men. J Nutr. 2009;139:987–992.
Diets high in fruits and vegetables, such as Mediterranean-style diets, are protective against chronic illness such as type 2 diabetes and cardiovascular disease. Risk for metabolic syndrome, a constellation of metabolic abnormalities, is reduced in Mediterranean-style diets. It is thought that some of the protective effects of these diets stem from antioxidants present in fruits and vegetables. Much research has focused on the vitamin C and vitamin E content of the diet in relation to chronic illness, but carotenoid intake is less well studied. Carotenoids in the diet come primarily from fruits and vegetables, and also from eggs, oils, and beverages, compounds in which the Mediterranean-style diet is rich. The present cross-sectional study examined the association between intake of dietary carotenoids and metabolic syndrome in middle-aged and elderly men. Independently living Dutch men (n = 3740) between the ages of 40 and 80 years were recruited through word-of-mouth and random sampling.
Dietary intakes of beta-carotene, alpha-carotene, beta-cryptoxanthin, lycopene, lutein, and zeaxanthin were assessed using a food-frequency questionnaire regionally validated for use in The Netherlands. Metabolic syndrome and associated risk factors were determined using waist-to-hip ratio, blood pressure, blood glucose, total cholesterol, HDL and LDL cholesterol, and triglyceride concentrations. Approximately 22% of participants had metabolic syndrome. Total intake of carotenoids, intake of lycopene, and higher quartiles of beta-carotene intake were inversely associated with risk for metabolic syndrome. Higher intakes of lycopene were associated with lower blood levels of triglycerides, and higher intake of most carotenoids was associated with lower fat mass and lower waist circumference. The authors concede that higher intake of carotenoids may serve as a marker for a healthier lifestyle overall. However, the present data suggest that carotenoids are deserving of further research in relation to risk factors for metabolic syndrome.
EARLY EXCLUSIVE BREASTFEEDING AND MORBIDITY IN ZIMBABWEAN INFANTS
Koyanagi A, Humphrey JH, Moulton LH, Ntozini R, Mutasa K, Iliff P, and Black RE. Effect of early exclusive breastfeeding on morbidity among infants born to HIV-negative mothers in Zimbabwe. Am J Clin Nutr. 2009;89:1375–1382.
Early exclusive breastfeeding (EBF) during the first 6 months of life, with continued breastfeeding for up to 1 year is recognized as the single most effective intervention in preventing mortality in children 5 years of age and younger. Non-exclusive breastfeeding accounts for some 10% of mortality in children under the age of 5 years. While breastfeeding in African countries is prolonged, exclusive breastfeeding is relatively rare. Benefits of EBF in the offspring of HIV-infected mothers include lower rates of postnatal HIV transmission than in non-EBF offspring. Little is known, however, about the relative benefits of EBF in offspring of HIV-negative African mothers. HIV-negative mother-infant pairs (n = 9207) from the Zimbabwe Vitamin A for Mothers and Babies (ZVITAMBO) trial were included in the reported analysis.
Mothers in this trial were well-educated and lived in relatively modern areas with access to electricity and clean water. Infant feeding information was collected from the mothers within 96 hours of delivery, and again at 6 weeks and at 3 months; the information collected pertained to exclusivity of breastfeeding versus introduction of any other foods during this time period. Infants were classified into EBF (breast milk only), predominant breastfeeding (breast milk and other liquids; no solid food), or mixed breastfeeding (includes solid food). Primary outcome measures included all-cause clinic visits, diarrheal illness-related visits, and lower respiratory tract infection-related visits between the ages of 43 and 182 days. EBF between birth and 3 months of age was associated with fewer overall clinic visits and, specifically, with lower rates of diarrheal illness in children aged 3–6 months. The benefits of EBF in respiratory tract infections were less pronounced, and the authors suggest that diarrheal illness may be caused directly by non-breast-milk foods, which may lead to malnutrition and subsequent susceptibility to other illnesses.
Comment: Dr. Kline comments that the protective effects of early exclusive breastfeeding hold tremendous potential for economic and public health concerns in rural African countries. Ongoing work should address the health and safety needs of mothers and infants in areas of endemic HIV/AIDS infection; attention should also be given to strategies for improving the acceptability of breastfeeding to women in these areas.
Comment: Kline MW. Early exclusive breastfeeding: still the cornerstone of child survival. Am J Clin Nutr. 2009;89:1281–1282.
THE DASH DIET AND RATES OF HEART FAILURE
Levitan EB, Wolk A, and Mittleman MA. Consistency with the DASH diet and incidence of heart failure. Arch Intern Med. 2009;169:851–857.
The Dietary Approaches to Stop Hypertension (DASH) diet is a set of dietary guidelines aimed at reducing blood pressure. Guidelines for this diet include high intake of fruits and vegetables, use of low-fat dairy products and whole grains, and low levels of fat consumption. The DASH approach is successful in the prevention and treatment of hypertension, but the associations between DASH and other cardiovascular events are less clear. The objective of the present observational study was to determine the ability of diets consistent with DASH patterns to reduce the incidence of heart failure. Data from 36,019 women (48–83 yrs) who were enrolled in the Swedish Mammography Cohort were used. Dietary assessments were obtained from food frequency questionnaires. DASH diet component scores were based on ranked intake of fruits, vegetables, nuts, legumes, low-fat dairy, whole grains, sodium, sweetened beverage, and red and processed meats. Possible scores ranges from 1 (non-DASH-like pattern) to 5 (highly DASH-like), and other dietary adherence scores were also used. Participants were followed for up to 7 years, and primary outcome measures included hospitalization or death from heart failure and incident myocardial infarction. Rates of heart failure were 37% lower in the upper quartile of women who most closely followed the DASH approach. While data from observational trials have limitations, the authors suggest that following a DASH diet is beneficial in reducing risk for heart failure in older women.
DIET AND EXERCISE INTERVENTIONS IN OLDER CANCER SURVIVORS
Morey MC, Snyder DC, Sloane R, Cohen HJ, Peterson B, Hartman TJ, Miller P, Mitchell DC, and Demark-Wahnefried W. Effects of home-based diet and exercise on functional outcomes among older, overweight long-term cancer survivors: RENEW: a randomized controlled trial. JAMA. 2009;301:1883–1891.
Long-term survival rates for many types of cancer are increasing; however, cancer survivors are at risk for accelerated functional decline, recurring malignancies, and other chronic illnesses. Older cancer survivors, in particular, are at risk for many lifestyle-related illnesses. While cancer survivors tend to be nonsmokers, other behaviors such as diet and exercise remain suboptimal. The objective of the present trial was to assess the effectiveness of telephone counseling and printed materials in behavioral change and reducing the rate of functional decline in older cancer survivors. Participants were enrolled in the Reach out to Enhance Wellness (RENEW) trial, which is a randomized controlled trial designed to assess home-based diet and exercise interventions and functional decline in long-term (≥5 years) breast, prostate, or colorectal cancer survivors. The present report includes data from 641 overweight, older cancer survivors (65–91 yrs).
Individuals were randomly assigned to either the intervention (n = 319) or control (delayed intervention; n = 322) condition. The intervention consisted of a 12-month, individualized workbook, quarterly newsletters, and telephone counseling to establish diet and exercise goals and progress. Recommendations included eating 7–9 servings/day of fruits and vegetables, restricting saturated fat to no more than 10% of calories, incorporating strength and endurance exercise, and establishing a 10% weight-loss goal within the year. The control participants were delayed for 12 months prior to receiving their interventions. Primary outcome for this trial was change in functional status between baseline and 12 months. Physical function was assessed using the Medical Outcomes Study Short-Form 36. Secondary outcomes pertained to the implementation of targeted diet and exercise behaviors. Over a 12-month period of time, physical decline was significantly slowed in the intervention group relative to the control condition. In the intervention condition, weight loss, physical activity, and improvements in diet and quality of life were significantly greater than in the control condition. The present data suggest that behavioral interventions can have a clinically meaningful influence on quality of life and can offset functional decline in older cancer survivors.