The relation of maternal weight to the blood pressures of Gambian children.

The objective of the study was to relate blood pressure levels in children to their mother's weight in pregnancy. The blood pressures of 675 children aged from one to nine years in three villages in rural Gambia were measured. They were matched to antenatal clinic data which had been collected from all pregnant women in the three villages since 1980. Among children under eight years of age those born in the dry season had the highest blood pressures and were heavier. Their blood pressures were positively related to body weight and to mothers' weight at six months of pregnancy. These relationships were independent of mothers' age and parity, birthweight, gestational age, and placental weight. Among older children, aged eight and nine years, those born in the rainy season had the highest blood pressures. Their blood pressures were not related to their mothers' weight at six months of pregnancy. Rather they were inversely related to mothers' weight gain in the last trimester. An interpretation of these findings is that among young children differences in blood pressure are largely determined by rates of maturation. However, the long-term effects of adverse intra-uterine influences which elevate blood pressure become apparent in older children.

PIP: Recent findings show that the intrauterine environment has a major effect on blood pressure and hypertension. This article reports on a study of the blood pressure of 675 Gambian children 1-9 years old and the relationship to mother's weight in pregnancy and seasonality. The children were born in the rural Keneba, Manduar, and Kanton Kunda in The Gambia after January 1980. Since 1979, clinic data was available on child's birth weight, growth, and morbidity data within the 1st 18 months, and after 18 months, clinic visit data on weight, height, diagnosis, and treatment. Mother's anthropometry and blood pressure (BP) were used at within 15 days of 6 months and 30 days of birth; mother's BP is not comparable between younger and older children. Periodic census data on households was also accessible. A study survey was also administered in 1989. Children's height was measured with a Harpenden infantometer for those 900 mm, and with a Raven Maximeter for those 900 mm. A SECA medal 727 (5 g gradations) was used for lower weights and a SOEHNLE digital scale for mother's and for heavier children. DINAMAP (model 18465 X) was used for 2 BP readings. A BP pretest with 2 observers revealed a mean difference in readings of .27 and a standard error of 1.36. Seasonality was set at rainy (Aug-Nov), cool (Apr-Jly), and hot and dry (Dec-Mar). The results were that systolic and diastolic pressures rose with children's age; i.e., from 89.3 mm Hg in 1 year olds to 102.7 mm Hg in 9 year olds. It increased with body weight and decreased with the time since the last meal. Ambient temperature was unrelated. Cole's LMS method for calculating centile curves was used to adjust the data for age, body weight, and time since eating. In the age groups 1-4, 5-7, mean BP was lowest during the rainy season and among 8-9 year olds, BP was highest during rainy seasons and variation was statistically significant. Mother's weight gain was lowest in the rainy season and among 8-9 year olds, BP was highest during rainy seasons and variation was statistically significant. Mother's weight gain was lowest in the rainy season and BP increased with age. Every 10mm Hg rise in mother's systolic BP was related to a 1 mm Hg rise in children's (1-7 years) adjusted systolic BP (p=.008). Mother's weight at 7.5 months was positively related to the child's (1-7 years) adjusted systolic BP (p=.003). There was no trend for children 8-9 years. Among the younger children BP was not related to mother's weight gain. Birthweight was unrelated to adjust systolic pressure at any age, but strongly positively related to mother's height, mother's weight at 7.5 months, and weight gain in the last trimester. Future followup is planned to examine whether the 6-7 year olds a year later begin to show the effects of maternal weight gain in pregnancy.

Increased birthweight after prenatal dietary supplementation of rural African women.

Birthweight data from 197 rural Gambian women who received an energy-dense prenatal dietary supplement over a 4-y period (net intake = 430 kcal/d) was compared with data from 182 women from 4 baseline years. Preintervention birthweights averaged 2944 +/- 43 (SEM) g when women were in positive energy balance during the dry harvest season (pregnancy weight gain greater than 1200 g/mo). Birthweights decreased to 2808 +/- 41 g (p less than 0.01) in the wet season when food shortages and agricultural work caused negative energy balance (weight gain less than 500 g/mo). There were no detectable secular trends in the baseline data. Supplementation was ineffective during the dry season but highly effective during the wet season: +225 +/- 56 g, p less than 0.001 (unadjusted) or +200 +/- 53 g, p less than 0.001 (adjusted for sex, season, and parity) by between-child multiple regression analysis; +231 +/- 65 g, p less than 0.001 by within-mother analysis. The proportion of low-birthweight babies (less than 2501 g) decreased from 23.7-7.5%, p less than 0.002. The observed threshold effect emphasizes the importance of selective targeting of interventions to truly at-risk groups.

PIP: Birthweight data from 197 rural Gambian women who received an energy-dense prenatal dietary supplement over a 4 year period (net intake = 430 kcal/day) was compared with data from 182 women from 4 baseline years. Preintervention birthweights averaged 2944 +or- 43 (SEM) grams when women were in positive energy balance during the dry harvest season (pregnancy weight gain 1200 gram/month). Birthweights decreased 2808 +or- 41 grams (p0.01) in the wet season when food shortages and agricultural work caused negative energy balance (weight gain 500 grams/month). There were no detectable secular trends in the baseline data. Supplementation was ineffective during the dry season but highly effective during the wet season: +225 +or- 56 frams, p0.001 (unadjusted) or +200 +or- 53 grams, p0.001 (adjusted for sex, season, and parity) by between-child multiple regression analysis; +231 +or- 65 grams, p0.001 by within-mother analysis. The proportion of babies of low birthweight (2501 grams) decreased from 23.7 to 7.5%, p0.002. The observed threshold effect emphasizes the importance of selective targeting of interventions to truly at-risk groups.

Changes in maternal and child mortality rates in three isolated Gambian villages over ten years.

As an adjunct to the general nutrition research programme, the MRC Dunn Nutrition Unit has provided for the past 10 years a continuous medical service to three adjacent rural Gambian villages. There have been substantial reductions in annual childhood mortality rates. Perinatal mortality fell from 109.6 to 45.5 per 1000 births, infant mortality from 148.5 to 24.5 per 1000 live births, and mortality in children aged 1-4 years from 109.1 to 13.3 per 1000. There have been no pregnancy-related maternal deaths in the community for 8 years; 16 could have been expected given current estimates of maternal mortality elsewhere in rural Gambia. Of all the health and nutritional interventions introduced the single most important factor has apparently been the on-the-spot, 24 h availability of a physician or qualified midwife.

PIP: As an adjunct to the general nutrition research program, the MRC Dunn Nutrition Unit has for the past 10 years provided a continuous medical service to 3 adjacent rural Gambian villages. There have been substantial reductions in annual childhood mortality rates: perinatal mortality fell from 109.6 to 45.5/1000 births, infant mortaliyt from 148.5 to 24.5/1000 live births, and mortality in children ages 1-4 from 109.1 to 13.3/1000. There have been no pregnancy-related maternal deaths in the community for 8 years, although 16 could have been expected given current estimates of maternal mortality elsewhere in rural Gambia. Of all the health and nutritional interventions introduced, the most improtant factor has apparently been the on-the-spot, 24-hour availability of a physician or qualifited midwife.

Efficacy of a food supplement in correcting riboflavin deficiency in pregnant Gambian women.

Pregnant women living in rural Gambian villages, whose natural riboflavin intake is about 0.5 mg/d, have abnormal biochemical riboflavin status and signs of clinical deficiency. A vitamin-fortified food supplement given in one village which increased the riboflavin intake to about 1.3 mg/d was followed by a substantial improvement in biochemical status, although seasonally-related variations in status somewhat complicated the picture. It was calculated that the amount of riboflavin needed to satisfy the requirement, for normal biochemical status, of the majority of pregnant women throughout pregnancy and throughout the year, is about 2.6 mg/d. Clinical signs associated with riboflavin deficiency, especially atrophic lingual papillae, showed significantly reduced incidence in the supplemented, compared with an unsupplemented, village. Cord blood values of the activation coefficient of erythrocyte glutathione reductase were in the abnormal range for 84 per cent of infants before introduction of the supplement, but were abnormal for only one of 12 infants after its introduction. Thus even a suboptimal maternal riboflavin intake of about 1.3 mg/d appears to be sufficient to prevent biochemical deficiency in cord blood, and to reduce considerably the incidence of clinical deficiency signs during pregnancy.

Riboflavin requirements of lactating Gambian women: a controlled supplementation trial.

As part of a study to determine the minimum allowance of riboflavin which is adequate for lactating women in a rural African environment, 60 subjects living in two Gambian villages were given either 2 mg riboflavin or a placebo daily on a double-blind basis for 12 wk. Their riboflavin intake from dietary sources was about 0.5 mg/day. In the supplemented group, the mean activation coefficient (AC) of erythrocyte glutathione reductase fell from 1.62 to 1.19 within 3 wk, and 90% had mean AC's below 1.3 throughout supplementation, whereas the placebo group maintained mean AC's between 1.6 and 1.9. Clinical signs associated with riboflavin deficiency improved more rapidly in the supplemented group; their breast milk riboflavin levels increased, and their infants' AC's were reduced, compared with those of the placebo group. After withdrawal of the supplement, the maternal and infants' AC's rose toward those of the placebo group. Thus a total riboflavin intake of about 2.5 mg/day during lactation is sufficient to maintain normal biochemical status in most Gambian women.