Health care in pregnancy during the COVID-19 pandemic and pregnancy outcomes in six low- and-middle-income countries: Evidence from a prospective, observational registry of the Global Network for Women's and Children's Health

Objective: To assess, on a population basis, the medical care for pregnant women in specific geographic regions of six countries before and during the first year of the coronavirus disease 2019 (COVID-19) pandemic in relationship to pregnancy outcom. Results: Across all sites, a small but statistically significant increase in home births occurred between the pre-COVID-19 and COVID-19 periods (18.9% versus 20.3%, adjusted relative risk [aRR] 1.12, 95% CI 1.05­1.19). A small but significant decrease in the mean number of antenatal care visits (from 4.1 to 4.0, p = <0.0001) was seen during the COVID-19 period. Of outcomes evaluated, overall, a small but significant decrease in low-birthweight infants in the COVID-19 period occurred (15.7% versus 14.6%, aRR 0.94, 95% CI 0.89­0.99), but we did not observe any significant differences in other outcomes. There was no change observed in maternal mortality or antenatal haemorrhage overall or at any of the sites. Conclusions: Small but significant increases in home births and decreases in the antenatal care services were observed during the initial COVID-19 period; however, there was not an increase in the stillbirth, neonatal mortality, maternal mortality, low birthweight, or preterm birth rates during the COVID-19 period compared with the previous year. Further research should help to elucidate the relationship between access to and use of pregnancy-related medical services and birth outcomes over an extended period

Protein-Energy Supplementation in Early-Life Decreases the Odds of Mental Distress in Later Adulthood in Guatemala

The prevalence of mental health concerns is growing worldwide, along with lack of access to and receipt of needed treatment. Current gaps in treatment provision have led to exploring alternative methods of prevention, with research linking nutrition and mental health, of particular relevance in low- and middle-income countries, with a high prevalence of undernutrition. To examine whether exposure to a protein-energy nutritional supplement during the first 1000 d of life decreased odds of mental distress in adulthood among men and women in Guatemala compared with receiving a low energy-no protein supplement or supplementation outside the 1000-d window. Data from participants (n = 1249) in a longitudinal cohort protein-energy supplementation trial (early-life, supplementation data from 1969 to 1977, ages 0­7 y; life course, outcome data from 2017­2018 follow-up, ages 40­57 y) were analyzed for associations between nutrition in the first 1000 d and mental distress in adulthood (WHO Self- Reporting Questionnaire 20 [SRQ-20]), controlling for early-life variables and current life stress; life course variables (e.g. education) were examined as potential mediators of this relation. Generalized linear mixed models and zero-inflated Poisson generalized linear mixed models were utilized. Both partial and full supplementation with Atole during the first 1000 d were associated with 63% (95% CI: 0.16, 0.87) and 56% (95% CI: 0.19, 1.03) lower odds, respectively, of experiencing mental distress in adulthood. Did not differ by sex. These inverse relations remained relatively unchanged (partial OR = 0.34 [95% CI: 0.14, 0.83]; full OR = 0.38 [95% CI: 0.16, 0.92]) after controlling for early-life and life course variables, including life stress. Protein-energy supplementation during the first 1000 d of life in Guatemala, where undernutrition is prevalent, may reduce the prevalence of later mental distress in adulthood. This effect appears to occur directly, rather than indirectly, through pathways of life course variables such as education, wealth, and marital status. Keywords: early childhood nutrition, protein-energy

Ultraprocessed Products as Food Fortification Alternatives: A Critical Appraisal from Latin America

Ultraprocessed products (UPPs), associated with obesity and non-communicable diseases (NCDs), are becoming predominant on the global market and a target for market-driven fortification initiatives. The aim of this article is to describe the implications of adding micronutrients to UPPs with excessive amounts of critical nutrients associated with NCDs and provide recommendations for legislation and policies. UPPs with added micronutrients such as breakfast cereals, sugarsweetened beverages, powder beverages, fruit juices, sauces, and bouillon cubes, among others, are commonly available and heavily promoted in Latin American countries. Misleading advertising of UPPs with added micronutrients and with excessive content of sugar, fat, and salt might increase the consumption of such products, giving them a "health halo effect" that leads consumers to overestimate their nutritional quality and healthfulness. Although international collections of standards such as the Codex Alimentarius provide some guidelines on this matter, countries need to implement national legislations, through a food systems approach, to regulate the marketing and labeling of UPPs. Lastly, there is still the need to foster research to close knowledge gaps and help countries to guide the process of food fortification strategies from a regulatory standpoint.

Knowledge, attitude and practices of pregnant women related to COVID-19 infection: A cross-sectional survey in seven countries from the Global Network for Women's and Children's Health

Objective. We sought to understand knowledge, attitudes and practices (KAP) regarding COVID-19 in pregnant women in seven low and middle-income countries (LMIC). Results. In all, 25 260 women completed the survey. Overall, 56.8% of women named ≥3 COVID-19 symptoms, 34.3% knew ≥2 transmission modes, 51.3% knew ≥3 preventive measures and 79.7% named at least one high-risk condition. Due to COVID-19 exposure concerns, 23.8% had avoided prenatal care and 7.5% planned to avoid hospital delivery. Over half the women in the Guatemalan site and 40% in the Pakistan site reduced care seeking due to COVID-19 exposure concerns. Of the women, 24.0% were afraid of getting COVID-19 from healthcare providers. Overall, 63.3% reported wearing a mask and 29.1% planned to stay at home to reduce COVID-19 exposure risk

Age at childbirth and change in BMI across the life-course: evidence from the INCAP Longitudinal Study

Background: Parity has been associated with both short- and long-term weight gain in women. However, it is not clear if timing of parity across the reproductive age has different associations with BMI. Methods: To prospectively assess the association between age at childbirth and maternal change in BMI, we analyzed data from the ongoing INCAP Longitudinal Study, which started in 1969 in four villages in Guatemala. Cohort women (n=778) provided information on reproductive history and anthropometric measures were measured in 1988-89 (adolescence, 15 to 25y), 2002-04 (early adulthood, 26 to 36y) and 2015-17 (mid adulthood, 37 to 55y). We evaluated the associations of number of live births in the period preceding each study wave (1969-77 to 1988-89, 1988-89 to 2002-04 and 2002-04 to 2015-17) with BMI change in the same period using multivariable linear regression models. Results: Number of live births between 1988 and 89 and 2002-04 was positively associated with increased BMI, while there was not an association between number of live births and BMI in the other intervals. Women who had one, two, or three or more children between 1988 and 89 and 2002-04 had 0.90 (kg/m2, 95% CI: -0.55, 2.35), 2.39 (kg/m2, 95% CI: 1.09, 3.70) and 2.54 (kg/m2, 95% CI: 1.26, 3.82) higher BMI, respectively, than women who did not give birth in the same period. Conclusions: Our findings suggest that women who had three or more children during early adulthood gained more weight compared to women who had no children in the same period. In contrast, women who had children earlier or later in their reproductive lives did not gain additional weight compared to those who did not have children during that period. Childbirth may have different

Desarrollo de preferencias alimentarias saludables en etapas tempranas de la vida / Development of healthy food preferences early in life

Resumen: Desarrollo de preferencias alimentarias saludables en etapas tempranas de la vida. El deterioro de la calidad de la dieta está afectando la salud de los niños menores de dos años. Por tal motivo, es de vital importancia la identificación de factores relacionados con el desarrollo y establecimiento de preferencias alimentarias en etapas tempranas de la vida y brindar recomendaciones que faciliten su adopción. Esta revisión sistemática de la literatura tiene como objetivo resumir la evidencia existente sobre los factores asociados a formar y modelar las preferencias alimentarias en etapas tempranas de la vida. Para esto se realizó una búsqueda en PubMed de estudios que evaluaran la asociación entre la exposición prenatal y posnatal de sabores, introducción temprana de alimentos y habituación al sabor dulce, alimentación complementaria y diversidad dietética. Se incluyeron artículos publicados desde el 2000 hasta el 2019. Resultados de 39 artículos sugieren que la alimentación durante los primeros dos años de vida y el desarrollo de preferencias alimentarias en etapas tempranas de la vida tiene el potencial de modificar los patrones de alimentación y establecerse en etapas posteriores de la vida, por lo que, los primeros mil días de vida constituyen una ventana de oportunidad para formar preferencias alimentarias saludables y mejorar la calidad de dieta de los niños.

Birth attendants as perinatal verbal autopsy respondents in low- and middle-income countries: a viable alternative?

OBJECTIVE: To assess the feasibility of using birth attendants instead of bereaved mothers as perinatal verbal autopsy respondents. METHODS: Verbal autopsy interviews for early neonatal deaths and stillbirths were conducted separately among mothers (reference standard) and birth attendants in 38 communities in four developing countries. Concordance between maternal and attendant responses was calculated for all questions, for categories of questions and for individual questions. The sensitivity and specificity of individual questions with the birth attendant as respondent were assessed. FINDINGS: For early neonatal deaths, concordance across all questions was 94%. Concordance was at least 95% for more than half the questions on maternal medical history, birth attendance and neonate characteristics. Concordance on any given question was never less than 80%. Sensitivity and specificity varied across individual questions, more than 80% of which had a sensitivity of at least 80% and a specificity of at least 90%. For stillbirths, concordance across all questions was 93%. Concordance was 95% or greater more than half the time for questions on birth attendance, site of delivery and stillborn characteristics. Sensitivity and specificity varied across individual questions. Over 60% of the questions had a sensitivity of at least 80% and over 80% of them had a specificity of at least 90%. Overall, the causes of death established through verbal autopsy were similar, regardless of respondent. CONCLUSION: Birth attendants can substitute for bereaved mothers as verbal autopsy respondents. The questions in existing harmonized verbal autopsy questionnaires need further refinement, as their sensitivity and specificity differ widely.

Causes of community stillbirths and early neonatal deaths in low-income countries using verbal autopsy: an International, Multicenter Study.

OBJECTIVE: Six million stillbirths (SB) and early neonatal deaths (END) occur annually worldwide, mostly in rural settings distant from health facilities. We used verbal autopsy (VA), to understand causes of non-hospital, community-based SB and END from four low-income countries. STUDY DESIGN: This prospective observational study utilized the train-the-trainer method. VA interviewers conducted standardized interviews; in each country data were reviewed by two local physicians who assigned an underlying causes of deaths (COD). RESULT: There were 252 perinatal deaths (118 END; 134 SB) studied from pooled data. Almost half (45%) the END occurred on postnatal day 1, 19% on the second day and 16% the third day. Major early neonatal COD were infections (49%), birth asphyxia (26%), prematurity (17%) and congenital malformations (3%). Major causes of SB were infection (37%), prolonged labor (11%), antepartum hemorrhage (10%), preterm delivery (7%), cord complications (6%) and accidents (5%). CONCLUSION: Many of these SB and END were from easily preventable causes. Over 80% of END occurred during the first 3 days of postnatal life, and >90% were due to infection, birth asphyxia and prematurity. The causes of SB were more varied, and maternal infections were the most common cause. Increased attention should be targeting at interventions that reduce maternal and neonatal infections and prevent END, particularly during the first 3 days of life.

An alternative strategy for perinatal verbal autopsy coding: single versus multiple coders.

OBJECTIVE: To determine the comparability between cause of death (COD) by a single physician coder and a two-physician panel, using verbal autopsy. METHODS: The study was conducted between May 2007 and June 2008. Within a week of a perinatal death in 38 rural remote communities in Guatemala, the Democratic Republic of Congo, Zambia and Pakistan, VA questionnaires were completed. Two independent physicians, unaware of the others decisions, assigned an underlying COD, in accordance with the causes listed in the chapter headings of the International classification diseases and related health problems, 10th revision (ICD-10). Cohen's kappa statistic was used to assess level of agreement between physician coders. RESULTS: There were 9461 births during the study period; 252 deaths met study enrolment criteria and underwent verbal autopsy. Physicians assigned the same COD for 75% of stillbirths (SB) (K = 0.69; 95% confidence interval: 0.61-0.78) and 82% early neonatal deaths (END) (K = 0.75; 95% confidence interval: 0.65-0.84). The patterns and proportion of SBs and ENDs determined by the physician coders were very similar compared to causes individually assigned by each physician. Similarly, rank order of the top five causes of SB and END was identical for each physician. CONCLUSION: This study raises important questions about the utility of a system of multiple coders that is currently widely accepted and speculates that a single physician coder may be an effective and economical alternative to VA programmes that use traditional two-physician panels to assign COD.

Relación entre circunferencia de cintura y presión arterial en mujeres guatemaltecas: el estudio CRONOS / The relation between waist circumference and blood pressure in Guatemalan women: the CRONOS study

Fundamentos: Diversos estudios han reportado una asociación entre presión arterial y obesidad central. El objetivo del estudio fue determinar la relación entre circunferencia de cintura (CC) y presión arterial (PA) en un grupo de mujeres jóvenes (J) y adultas mayores (M) residentes en Quetzaltenango, Guatemala. Métodos: Se estudiaron 196 mujeres, 97 de 35-45 años (J) y 99 de 60-75 años (M) a través del protocolo genérico CRONOS. Se definió hipertensión como presión sistólica (PS) ≥140 mmHg y presión diastólica (PD) ≥ 90 mmHg. Resultados: Para mujeres J y M el porcentaje de hipertensas fue de 9 y 40% respectivamente; el 38% de las mujeres J presentaron sobrepeso, en relación con el 45% de las M; la obesidad fue del 28% para las J y del 23% para las M. Los promedios de CC fueron comparables en ambos grupos: J = 82,5 ± 9,7 cm y M = 82,5 ± 9,9 cm; las correlaciones de Pearson y Spearman entre CC, PS y PD para el grupo J no fueron significativas (p > 0,05). La correlación entre CC y PD en mujeres M fue significativa (Pearson: r = 0,34; p < 0,01 y Spearman: r = 0,35; p < 0,01). Conclusiones: En esta población con marcado sobrepeso y obesidad la asociación positiva entre CC y PA solamente fue observada en las mujeres adultas mayores con un porcentaje de hipertensión más elevado(AU)

Fundaments: Several studies have reported an association between blood pressure and central adiposity. The objective of this study was to determine the relationship of waist circumference (WC) and blood pressure (BP) among a group of young (Y) and old (O) women living in Quetzaltenango, Guatemala. Methods: 196 women, 97 between 35-45y (Y), and 99 from 60 to 75y (O), using a multicentric protocol from CRONOS study. Hypertension was defined as systolic blood pressure (SBP) ≥140 mmHg and diastolic blood pressure (DBP) ≥ 90 mmHg. Results: For the Y and O groups, the percentage of hypertension was 9% and 40%, respectively; 38% of the Y group were overweight, as compared to 45% of the O group. Obesity was 28% in the Y group and 23% in the O group. Mean WC was identical between groups: Y= 82,5 ± 9,7 cm and O= 82,5 ± 9,9 cm; the Pearson and Spearman correlations between WC and SBP or DBP were not significant for the young group (p > 0,05). In the older group, the correlation between WC and DPB was significant in both: Pearson (r = 0,34; p < 0,01) and Spearman (r = 0,35, p < 0,01). Conclusions: In this particular population with overweight and obesity, the positive association between WC and BP was observed in the older women group, who also has the mayor percentage of hypertension(AU)

Ingesta de fibra dietética y su relación con el perfil lipídico de adultos guatemaltecos / Dietetic fiber intake and its relationship with the lipid profile in Guatemalan adults

Fundamentos: En Latinoamérica la transición epidemiológica y el paradigma de las enfermedades crónicas ha emergido, siendo las enfermedades cardiovasculares las que encabezan la lista de morbilidad. Métodos: Como parte de un estudio multicéntrico se evaluó la ingesta de fibra dietética y su relación con los niveles de lípidos séricos en 170 sujetos residentes en el área rural de Guatemala. Resultados: La ingesta calórica promedio de la población fue 2.521 ± 788 kcal, mientras la de fibra dietética fue de 37,4 ± 9,3 g/día. El perfil lipídico presentó valores de colesterol total de 202 ± 44 mg/dl, triglicéridos 209 ± 97 mg/dl, lipoproteínas de alta densidad 26,7 ± 5,7 mg/dl y lipoproteínas de baja densidad 136 ± 42 mg/dl. La relación entre ingesta de fibra dietética y los lípidos séricos no tuvo significación estadística. Conclusiones: El efecto hipolipidémico de la fibra tiene un límite más allá del cual, a pesar de seguir elevando el consumo de fibra, los niveles de lípidos no se reducen más. Lo anterior hace pensar que la población examinada podría estar en riesgo de hiperlipidemia de no ser por la ingesta de fibra aquí reportada. La población tiene un mayor consumo de fibra insoluble, por lo que es posible hipotetizar que los niveles de lípidos se han reducido de una manera similar, con lo cual se pierde el efecto de dosis-respuesta(AU)

Background: In Latin America, the epidemiological transition and the paradigm of chronic diseases have emerged, with cardiovascular diseases now the leading cause of morbidity. Methods: As part of a multicentric study, the intake of dietetic fiber and its relationship with the levels of serum lipids was evaluated in 170 subjects residing in rural Guatemala. Results: The average dietary energy intake for this population was 2521 ± 788 kcal, while that of dietary fiber was 37.4 ± 9,3 g/d. Lipid profile showed mean values of total cholesterol 202±44 mg/dl; triglicerides 209±97 mg/dl; HDL 26.7 ± 5.7 mg/dl; LDL 136 ± 42.0 mg/dl. We found no association between fiber intake and serum lipids. Conclusions: The hypolipidemic effect of the fiber has a limit beyond which, no matter the increase inf the fiber consumption, the lipid levels will not reduce further. This leads to the speculation that the population could be on risk of hyperlipidemia if they did not consume the intakes of fiber reported. However, the population has greater intake of insoluble fiber; therefore is possible to hypothesize that the lipid levels have been reduce in a similar way in which case, the dose-response effect, is lost(AU)

Using verbal autopsy to ascertain perinatal cause of death: are trained non-physicians adequate?

OBJECTIVES: To develop a standardized verbal autopsy (VA) training program and evaluate whether its implementation resulted in comparable knowledge required to classify perinatal cause of death (COD) by physicians and non-physicians. METHODS: Training materials, case studies, and written and mock scenarios for this VA program were developed using conventional VA and ICD-10 guidelines. This program was used to instruct physicians and non-physicians in VA methodology using a train-the-trainer model. Written tests of cognitive and applied knowledge required to classify perinatal COD were administered before and after training to evaluate the effect of the VA training program. RESULTS: Fifty-three physicians and non-physicians (nurse-midwives/nurses and Community Health Workers [CHW]) from Pakistan, Zambia, the Democratic Republic of Congo, and Guatemala were trained. Cognitive and applied knowledge mean scores among all trainees improved significantly (12.8 and 28.8% respectively, P < 0.001). Cognitive and applied knowledge post-training test scores of nurse-midwives/nurses were comparable to those of physicians. CHW (high-school graduates with 15 months or less formal health/nursing training) had the largest improvements in post-training applied knowledge with scores comparable to those of physicians and nurse-midwives/nurses. However, CHW cognitive knowledge post-training scores were significantly lower than those of physicians and nurses. CONCLUSIONS: With appropriate training in VA, cognitive and applied knowledge required to determine perinatal COD is similar for physicians and nurses-midwives/nurses. This suggests that midwives and nurses may play a useful role in determining COD at the community level, which may be a practical way to improve the accuracy of COD data in rural, remote, geographic areas.

Plasma free amino acid concentrations in healthy Guatemalan adults and in patients with classic dengue.

BACKGROUND: Plasma free amino acid patterns in health and disease have been reported. However, amino acid concentrations in adult populations in developing countries and in patients with dengue, as a model for an acute infectious viral disease endemic to the tropics, have not been reported. OBJECTIVE: The purpose of this study was to determine the amino acid profile in both healthy Guatemalan adults from different socioeconomic backgrounds and at 3 time points during the course of classic dengue. DESIGN: The study was carried out in Guatemala and included measurement of plasma free amino acids in 22 healthy control subjects (14 low income, 8 middle class) and 17 febrile patients. Measurements of amino acids were repeated within a 48-h interval in 20 of the healthy Guatemalans. In 9 patients with dengue, amino acids were assayed 3 times: on admission to a local hospital in the coastal plain of Guatemala, on hospital discharge, and 7 d after hospital discharge. RESULTS: Branched-chain amino acid concentrations in healthy adults and dengue patients in Guatemala were lower than normal values reported in the literature for healthy Swedish adults. With the exception of increased phenylalanine concentrations and an increased ratio of phenylalanine to tyrosine, all amino acids as well as the Fischer molar ratio were decreased in the acute phase of dengue. CONCLUSIONS: Healthy Guatemalans have different amino acid patterns than do Swedish subjects independent of socioeconomic status. The systemic viral disease dengue is associated with changes in the plasma free amino acid pattern, reflecting infection-related alterations in amino acid metabolism.

Hydrational status assessed by bioelectrical impedance spectroscopy and dilution methods in patients with classical dengue fever.

The effects of an episode of acute classical dengue fever on extracellular water (ECW), intracellular water (ICW), and total body water (TBW) were measured in nine patients using conventional dilution techniques; and the findings were compared with the outcome variables from whole body impedance spectroscopy (BIS), extracellular fluid resistance (Recf), and intracellular fluid resistance (Ricf). The patients were assessed on admission with febrile presentation (DI), at discharge after the defervescence of the fever cycle at about five days postadmission (DII), and seven days thereafter (DIII). As a reference group, 15 persons without acute or chronic illness were enrolled. Total body water was unaltered during the course of disease and was not different from that in normal healthy subjects. However, body water shifted from the intracellular to the extracellular compartment in patients from the acute phase to convalescence, as reflected in the ratios of ECW/TBW and ECW/ICW. These ratios were significantly higher in convalescent dengue patients (DIII) than in the reference group (p < 0.05). Increasing ECW, from the acute phase of the disease to convalescence, was associated with a significant decrease in Recf (719 +/- 95, 693 +/- 89, 643 +/- 81 omega; p < 0.0001) and in Recf/Ricf (p < 0.01). Recf and Recf/Ricf were higher in the acute phase (DI) of dengue fever compared to controls (p < 0.05). We conclude that dengue fever is characterized by a relative expansion of ECW during the course of disease and convalescence. BIS was sensitive in determining the hydrational profile in dengue fever patients.

Bioelectrical impedance spectroscopy in health and disease. Correspondence between whole body and segmental bioelectrical impedance spectroscopy indices in patients with classical dengue fever.

Bioelectrical impedance spectroscopy (BIS) can provide estimates of body composition for both whole body (WB) and body segments (BS). In normal, healthy subjects, BS measurements may be expected to serve as surrogates for WB indices; however, very little is known about this correspondence in people suffering from acute illnesses. The aim of this study was to evaluate the degree of this correspondence in patients with an acute, systemic illness, such as classical dengue fever. Ten adult patients were examined upon admission to the community hospital on the Pacific Coast of Guatemala and after clinical recovery about two weeks later, and compared with a group of healthy subjects living in the same region. BIS was measured with a Xitron 4000B analyzer (Xitron Technologies Inc., San Diego, CA, USA). BS measurements were carried out using Organ et al.'s approach. The BIS data were modeled with the manufacturer's software: extra- (Recf) and intracellular- (Ricf) resistances, and the Recf/Ricf ratio. BIS BS measurements correlate closely with WB in both the acute and the recovery stages of dengue fever, with the leg showing the highest degree of correspondence and the trunk the lowest. Recf indices, per se, generally showed higher correspondence than Ricf or the Recf/Ricf ratio.

The pharmacokinetic responses of humans to 20 g of alanyl-glutamine dipeptide differ with the dosing protocol but not with gastric acidity or in patients with acute Dengue fever.

Pharmacokinetic responses to oral doses of the dipeptide, L-alanyl-glutamine (Ala-Gln), were evaluated after a single, bolus load or an intermittent dosing in normal healthy subjects (n = 8) to find the optimal mode of oral administration. In a subgroup (n = 4) of the healthy subjects, the influence of a gastric acid suppressor (Omeprazole) was investigated. The influence of an acute episode of classic Dengue fever was examined in eight patients. All modes of administration to healthy subjects significantly increased free plasma Gln and alanine concentrations. Peak increments of plasma Gln concentration were 794+/-107 micromol/L (mean +/- SEM) after bolus intake of 20 g of Ala-Gln and 398+/-61 micromol/L after intermittent intake of the same cumulative dosage of the dipeptide (P<0.01). After intermittent dosing, the maximum peak increase appeared significantly later (P<0.01). Areas under the curve (AUC), expressing the integrated responses over time of plasma free Gln and alanine concentrations, did not differ after bolus and intermittent loads of Ala-Gln. Pretreatment with the acid suppressor, Omeprazole, did not influence Gln (P = 0.79) or alanine (P = 0.90) plasma increment. Dengue patients manifested the same pharmacokinetic responses to a 20 g Ala-Gln bolus as healthy controls. In general, on a micromolar concentration basis, Gln and alanine followed parallel tracks in terms of plasma appearance, clearance and elimination after the oral administration of 20 g of the Ala-Gln dipeptide through the range of conditions and dosing protocols explored here.

Assessment of total body stores of vitamin A in Guatemalan elderly by the deuterated-retinol-dilution method.

BACKGROUND: Deuterated retinol dilution (DRD) gives quantitative estimates of total body stores of vitamin A. OBJECTIVES: In elderly people, we studied 1) the time when an oral dose of deuterated vitamin A equilibrates with body stores, 2) whether serum ratios of deuterated to nondeuterated retinol (D:H) at 3 or 6 d postdosing predicted body stores, and 3) the ability of DRD to detect changes in the size of the body vitamin A pool. DESIGN: A 10-mg oral dose of [2H4]retinyl acetate was administered to 60-81-y-old Guatemalans (n = 47); percentage enrichment of serum retinol with deuterated retinol was determined at 1-3 time points per subject at 3, 6, 7, 14, 20, 21, and 54 d. In subjects from whom blood was obtained at 3 and 21 d (n = 15) and at 6 and 20 d (n = 9), total body stores were calculated by using the formula of Furr et al (Am J Clin Nutr 1989;49:713-6) with 21- or 20-d data and correlated with serum D:H at 3 or 6 d postdosing. Nine subjects received diets containing 982+/-20 microg RE (x+/-SEM) plus 800 microg RE as retinyl acetate supplements for 32 d. DRD, serum retinol, and relative dose response were used to assess vitamin A status before and after the intervention. RESULTS: Deuterated retinol equilibrated with the body pool by 20 d postdosing. Vitamin A supplementation for 32 d increased body stores, although unexplained exaggerated increases were seen in some subjects. An inverse linear relation was found between estimates of body stores and serum D:H at 3 d postdosing (r = -0.75, P = 0.002); at 6 d postdosing, the correlation was weaker. CONCLUSIONS: DRD can detect changes in total body stores of vitamin A, although factors affecting serum D:H need to be elucidated. Serum D:H 3 d postdosing might be used as an early indicator of total body stores of vitamin A, although a predictive equation will need to be developed.

Influence of sex, seasonality, ethnicity, and geographic location on the components of total energy expenditure in young children: implications for energy requirements.

BACKGROUND: There are limited data on the influence of body composition, sex, seasonality, ethnicity, and geographic location on the components of energy expenditure in children. OBJECTIVE: The objective was to examine the determinants of total energy expenditure (TEE), resting energy expenditure (REE), and activity-related energy expenditure (AEE) in children. DESIGN: Cross-sectional data from 232 children (4-10 y of age) from 4 ethnic groups (white American, African American, Guatemalan Mestizo, and Native American Mohawk) were examined. RESULTS: In 104 white children studied in Vermont and Alabama, TEE was significantly higher in spring than in fall, higher in boys than in girls, and higher in children in Vermont (all effects: approximately 0.42 MJ/d, P < 0.05). The significant effect of sex was explained through REE; the influences of season and location were explained through AEE. In all children, there was no effect of sex but a significant effect of ethnicity (P < 0.01) on TEE: a significant effect of sex (P < 0.01) and no effect of ethnicity (P = 0.16) on REE; and no effect of sex and a significant effect of ethnicity on AEE. The significant effects of ethnicity were due to lower values in Guatemalan children. TEE correlated most strongly with weight (r = 0.81) and fat-free mass (r = 0.79-0.81); REE with weight (r = 0.85) and fat-free mass (r = 0.80-0.87); and AEE with maximal oxygen consumption (r = 0.54), fat-free mass (r = 0.50), and fat mass (r = 0.49). CONCLUSIONS: 1) Season and location influenced TEE in children through their effects on AEE, 2) a higher REE in boys was consistent across all groups examined, 3) Guatemalan children had lower TEE due to a lower AEE, 4) body weight may be the best predictor of TEE, and 5) maximal oxygen consumption was the strongest marker of AEE.