Effects of subclinical infection on plasma retinol concentrations and assessment of prevalence of vitamin A deficiency: meta-analysis.

BACKGROUND: Vitamin A deficiency adversely affects child morbidity and survival. This deficiency is estimated by measurement of plasma retinol concentrations, but because plasma retinol is reduced by clinical and subclinical infection, this proxy measure can lead to overestimation. Infection and trauma are accompanied by rises in concentrations of acute-phase proteins in plasma. We aimed to estimate vitamin A deficiency more accurately by measuring changes in plasma retinol and acute-phase proteins associated with subclinical infection or convalescence. METHODS: We analysed data for concentrations of plasma retinol and one or more acute-phase proteins (alpha1-acid-glycoprotein, alpha1-antichymotrypsin, C-reactive protein, or serum amyloid A) from 15 studies of apparently healthy individuals. We generated summary estimates of differences in retinol concentrations for incubation, early, and late convalescent phases of infection between people with none and those with one or more raised acute-phase proteins. We compared these groups in two, three, and four group analyses. We also compared a subgroup of apparently healthy preschool (1-5 years) children with results from all other studies. FINDINGS: For all four proteins, retinol values were much higher in people with normal concentrations of protein, than in individuals with raised concentrations (16% higher for alpha1-antichymotrypsin, 18% for alpha1-acid-glycoprotein, 25% for C-reactive protein, and 32% for serum amyloid A). Estimates of the reduction in plasma retinol for individuals with infection compared with healthy individuals, were 13% (incubation), 24% (early convalescent), and 11% (late convalescent). Estimates of vitamin A deficiency in individuals with no raised acute-phase proteins (healthy group) were much the same as those obtained by adjustment of plasma retinol concentrations in the whole group using acute-phase proteins. INTERPRETATION: We recommend that surveys to estimate vitamin A deficiency should include measurements of serum C-reactive protein and alpha1-acid-glycoprotein concentrations. Information about acute-phase proteins will enable plasma retinol concentrations to be corrected where sub-clinical infection exists, and the healthy sub-group to be identified.

Diet during lactation associated with infant behavior and caregiver-infant interaction in a semirural Egyptian village.

Potential processes through which nutritional and non-nutritional factors can relate to infant state and behavior and mother-infant interactions were examined in 41 mother-infant pairs from semirural Egyptian households. All infants were breast-fed, and breast milk was the main source of their nutrient intake. Median birth weight was close to reference median; however, most infants showed growth faltering when they were 3-6 mo of age. Among the infant behavioral and state variables, only drowsiness (a proxy for activity and alertness) was significantly associated with the nutritional and non-nutritional factors examined. Among these factors, mothers' intakes of animal source foods and certain B vitamins were the strongest predictors of drowsiness. The nature of the association between maternal diet and drowsiness, examined by multiple regression analysis, showed clearly that inadequate diet of the mother was the major risk factor. Alertness of infants was further compromised when there were several children in the households. The small, less vocal and less alert infants received less vocalization from their mothers. In this environment, infants of undernourished mothers may not receive the extra care and stimulation needed and are at risk for subsequent developmental disabilities.

PIP: Each week physicians visited the households of 41 mother-infant pairs living in Kalama, Egypt, to examine infant behavior and caregiver-infant interactions from 3 to 6 months of age, as they relate to various factors, e.g., maternal nutrition and health and socioeconomic status. All the mothers breast fed their infants. Liquids which are inferior sources of energy and nutrients were the most customary food supplements during the first 6 months. Even though the median birth weight tended to equal that of the WHO international reference, most infants experienced faltering growth by 3 months. At 6 months, 75% were below the 25th percentile and 20% were in the 5th percentile. Growth faltering was linked with increased diarrhea (p .05). Even though the mothers' diets contained sufficient niacin, thiamin, folate, and vitamin C, the diets did not supply mothers enough riboflavin, vitamin B-6, vitamin A, calcium, and zinc. Breast milk did not have adequate amounts of vitamin B-6 and, perhaps, not even enough riboflavin and vitamin A. It did contain adequate amounts of calcium, however. Drowsiness was significantly related to maternal diet during lactation but not during pregnancy (especially energy intake from animal sources, p = .0001; energy intake from plant sources, p = .03); number of siblings (p = .009); crowding (p = .06); vocalization from mothers (p = .08); and low socioeconomic status (p = .07). Maternal diet was the best predictor of drowsiness followed by number of siblings. Without remediation in maternal nutrition, infants of undernourished mothers appeared not to receive appropriate care and stimulation, therefore placing them at risk of subsequent development disabilities. Intervention studies should be done to examine this main effect of maternal undernutrition and the importance of covarying environmental risk factors, e.g., crowding.

Determinants of pregnancy outcome and newborn behavior of a semirural Egyptian population.

Several potential determinants of birth weight and neonatal behavioral organization, ie, maternal anthropometry, food intake (energy, protein, and plant- and animal-source foods), morbidity, and household socioeconomic status, were followed systematically in a semirural Egyptian population during greater than or equal to 6 mo of pregnancy. In early pregnancy mothers were generally normal weight to moderately overweight. Their mean energy intake, largely from plant sources, was approximately 8.37 MJ/d (2000 kcal/d) during trimesters 2 and 3. Early (3 mo) pregnancy weight and weight gain during trimesters 2 and 3 were significantly positively related to birth weight Z scores. The best predictor model examined for birth weight included early pregnancy weight, weight gain, and length of gestation (R2 = 0.45). Early pregnancy weight and maternal intake of animal-source foods were significant positive predictors of the newborn's orientation and habituation behavior, respectively. Habituation and orientation measures assess the infant's early ability to process information.

Teacher characteristics and the inclusion of sex education topics in grades 6-8 and 9-11.

PIP: The project purpose was to determine whether selected personal characteristics of health science teachers of school grades 6-8 and 9-11 were related to 1 measure of sex education teaching performance--the inclusion of topics within the instructional unit. The study population was limited to 269 health science teachers in public schools in Indiana, with 94 teaching within grades 6-8 and 175 teaching in grades 9-11. Some significant relationships were established between the teacher characteristic variables and the 60 sex education topics. None of the teacher characteristics variables were consistently related to the inclusion of the topics when considering the topics as a group, although significance was found more frequently at the 9-11 grade than at the 6-8 grade level. More significant relationships were established for the variable erotophila-erotophobia (persons who associate primarily positive emotions with sexuality are considered erotophilics, and individuals associating primarily negative emotions with sex are classified as erotophobics) than for any other teacher characteristic. Erotophilic individuals more often included the birth control topics within sex education instruction. For the teachers in grades 9-11, those with the master's degree in health education were more likely than those without the advanced degree to include sexual behavior-related topics.^ieng