Omolola Ayoola

Effects of early growth on blood pressure of infants of British European and South Asian origin at one year of age: The Manchester children's growth and vascular health study

Objective The objective of this study was to investigate early influences of postnatal growth on blood pressure (BP) in healthy, British-born South Asian and European origin infants. We tested the hypotheses that South Asian infants would be smaller in all body dimensions (length and weight) with higher relative truncal skinfold thickness at birth, and that increased (central) adiposity and accelerated growth up to 1 year would be associated with higher BP in both ethnic groups. Patients and methods Five hundred and sixty infants were followed prospectively from birth to 3 and/or 12 months with measures of anthropometry and resting BP, compared against a UK 1990 growth reference, and analysed using regression methods. Results Marked differences in birth size persisted, as expected, between European and South Asian babies, but with a sexual dichotomy: South Asian boys were smaller in all anthropometric parameters (P < 0.001), including skinfolds (P < 0.05), than European boys, but South Asian girls, although smaller in length and weight, had similar skinfolds to European girls and thus a slightly larger subscapular skinfold thickness relative to birth weight [1.3 versus 1.2, mean difference 0.07, 95% confidence interval (CI) 0.0009–0.14, P = 0.047]. The dichotomy persisted postnatally; South Asian boys showed a striking early increase in weight and length compared with European boys, associated with significant accrual of subscapular fat (6.1 versus 5.3 mm, mean difference 0.8, 95% CI 0.3–1.3, P = 0.003). In gender and ethnicity adjusted regression models, infants with the largest weight standard deviation score (SDS) increases in the first 3 months had the highest 12-month systolic BP (β = 2.4, 95% CI 0.5–4.2, P = 0.01), while those with the greatest birth length (β = 0.7, 95% CI 0.05–1.4, P = 0.04) but the smallest changes in length over 3–12 months (β = −0.57, 95% CI −0.95 to −0.19, P = 0.004) had the highest diastolic BP. Conclusions Ethnic and gender differences in growth and adiposity present in early infancy include truncal fat preservation in South Asian girls from birth, which in boys is related to rapid early weight gain. Weight gain during the first 3 months appears to drive the rise in systolic BP to 1 year, itself a likely driver of later BP.

Maternal malaria status and metabolic profiles in pregnancy and in cord blood: relationships with birth size in Nigerian infants

BackgroundMalaria is more common in pregnant than in non-pregnant Nigerian women, and is associated with small birth size and the attendant short- and long-term health risks. The influence of malaria on maternal metabolic status in pregnancy and in cord blood and how this relates to birth size has not been studied. The study objective was to define relationships between maternal and cord serum metabolic markers, maternal malaria status and birth size.MethodsDuring pregnancy, anthropometric measurements, blood film for malaria parasites and assays for lipids, glucose, insulin and TNF were obtained from 467 mothers and these analytes and insulin-like growth factor-I (IGF-I) were obtained from cord blood of 187 babies.ResultsOverall prevalence of maternal malaria was 52%, associated with younger age, anaemia and smaller infant birth size. Mothers with malaria had significantly lower cholesterol (total, HDL and LDL) and higher TNF, but no difference in triglyceride. In contrast, there was no effect of maternal malaria on cord blood lipids, but the median (range) cord IGF-I was significantly lower in babies whose mothers had malaria: 60.4 (24,145)μg/L, versus no malaria: 76.5 (24, 150)μg/L, p = 0.03. On regression analysis, the key determinants of birth weight included maternal total cholesterol, malarial status and cord insulin and IGF-I.ConclusionsMalaria in pregnancy was common and associated with reduced birth size, lower maternal lipids and higher TNF. In the setting of endemic malaria, maternal total cholesterol during pregnancy and cord blood insulin and IGF-I levels are potential biomarkers of foetal growth and birth size.

Relative Height and Weight among Children and Adolescents of Rural Southwestern Nigeria

Background: There are few data describing the relative height and weight patterns of children and adolescents in rural Nigeria, despite a prevalence of stunting of over 38% among children younger than 5 years. Aim: The present study documented the height and weight patterns relative to international standards among children and adolescents aged 5–20 years in rural Nigeria. Subjects and methods: Children 5–20 years of age were enrolled from two rural villages. Height and weight were measured; body composition was estimated using bioelectrical impedance analysis. z-scores and centiles for height and body mass index were calculated; prevalences of low relative height (i.e.>2 standard deviations below mean for age and sex) and weight by sex and age were estimated. Results: A total of 623 participants (326 male and 297 female) were enrolled. The mean height-for-age z-score for males younger than 19 years was –2.1 and prevalence of low relative height was 50%. Among females, the mean height-for-age z-score was –1.2 during adolescence; only 15% of adolescent females were of low relative height. Based on BMI-for-age, 37% of the adolescent males and 23% of females were underweight. No children or adolescents were overweight based on BMI-for-age. Conclusions: Low relative height and underweight occur in a large proportion of children and adolescents in rural Nigeria, with the lowest relative heights and weights occurring in mid-adolescence and among males.

The Impact of Malaria in Pregnancy on Changes in Blood Pressure in Children During Their First Year of Life

We established a maternal birth cohort in Ibadan, Nigeria, where malaria is hyperendemic, to assess how intrauterine exposure to malaria affected infant blood pressure (BP) development. In a local maternity hospital, healthy pregnant women had regular blood films for malaria parasites from booking to delivery. Growth and BP were measured on 318 babies, all followed from birth to 3 and 12 months. Main outcomes were standardized measures of anthropometry and change in BP to 1 year. Babies exposed to maternal malaria were globally smaller at birth, and boys remained smaller at 3 months and 1 year. Change in systolic BP (SBP) during the year was greater in boys than in girls (20.9 versus 15.7 mm Hg; P=0.002) but greater in girls exposed to maternal malaria (18.7 versus 12.7 mm Hg; 95% confidence interval, 1–11 mm Hg; P=0.02). Eleven percent of boys (greater than twice than expected) had a SBP ≥95th percentile (hypertensive, US criteria), of whom 68% had maternal malaria exposure. On regression analysis (&bgr; coefficients, mm Hg), sex (boys>girls; &bgr;=4.4; 95% confidence interval, 1.1–7.7; P=0.01), maternal malaria exposure (3.64; 0.3–6.9; P=0.03), and weight change (2.4; 0.98–3.8/1 standard deviation score; P=0.001) all independently increased SBP change to 1 year, whereas increase in length decreased SBP (−1.98; −3.6 to −0.40). In conclusion, malaria-exposed boys had excess hypertension, whereas malaria-exposed girls a greater increase in SBP. Intrauterine exposure to malaria had sex-dependent effects on BP, independent of infant growth. Because infant–child–adult BP tracking is powerful, a malarial effect may contribute to the African burden of hypertension.

Maternal Malaria, Birth Size and Blood Pressure in Nigerian Newborns: Insights into the Developmental Origins of Hypertension from the Ibadan Growth Cohort

Background Hypertension is an increasing health issue in sub-Saharan Africa where malaria remains common in pregnancy. We established a birth cohort in Nigeria to evaluate the early impact of maternal malaria on newborn blood pressure (BP). Methods Anthropometric measurements, BP, blood films for malaria parasites and haematocrit were obtained in 436 mother-baby pairs. Women were grouped to distinguish between the timing of malaria parasitaemia as ‘No Malaria’, ‘Malaria during pregnancy only’ or ‘Malaria at delivery’, and parasite density as low (<1000 parasites/µl of blood) and high (≥1000/µl). Results Prevalence of maternal malaria parasitaemia was 48%, associated with younger maternal age (p<0.001), being primigravid (p = 0.022), lower haematocrit (p = 0.028). High parasite density through pregnancy had the largest effect on mean birth indices so that weight, length, head and mid-upper arm circumferences were smaller by 300 g, 1.1 cm, 0.7 cm and 0.4 cm respectively compared with ‘No malaria’ (all p≤0.005). In babies of mothers who had ‘malaria at delivery’, their SBPs adjusted for other confounders were lower respectively by 4.3 and 5.7 mmHg/kg compared with ‘malaria during pregnancy only’ or ‘none’. In contrast the mean newborn systolic (SBP) and diastolic BPs (DBP) adjusted for birth weight were higher by 1.7 and 1.4 mmHg/kg respectively in babies whose mothers had high compared with low parasitaemia. Conclusions As expected, prenatal malarial exposure had a significant impact on fetal growth rates. Malaria at delivery was associated with the lowest newborn BPs while malaria through pregnancy, which may attenuate growth of the vascular network, generated higher newborn BPs adjusted for size. These neonatal findings have potential implications for cardiovascular health in sub-Saharan Africa.

Country-based reference values and international comparisons of clitoral size in healthy Nigerian newborn infants.

Clitoral size references are useful for diagnosing genital abnormalities. Despite the fact that examining the genitalia is an important aspect of newborn evaluation, few studies have been carried out to determine normal clitoral size in newborn infants. The aim of this study was to establish reference values for clitoral size in Nigerian newborn girls and to compare them with references from other ethnic populations.