Elizabeth A Lundeen

Postinfancy growth, schooling, and cognitive achievement: Young Lives

Background: Early life growth failure and resulting cognitive deficits are often assumed to be very difficult to reverse after infancy. Objective: We used data from Young Lives, which is an observational cohort of 8062 children in Ethiopia, India, Peru, and Vietnam, to determine whether changes in growth after infancy are associated with schooling and cognitive achievement at age 8 y. Design: We represented the growth by height-for-age z score at 1 y [HAZ(1)] and height-for-age z score at 8 y that was not predicted by the HAZ(1). We also characterized growth as recovered (stunted at age 1 y and not at age 8 y), faltered (not stunted at age 1 y and stunted at age 8 y), persistently stunted (stunted at ages 1 and 8 y), or never stunted (not stunted at ages 1 and 8 y). Outcome measures were assessed at age 8 y. Results: The HAZ(1) was inversely associated with overage for grade and positively associated with mathematics achievement, reading comprehension, and receptive vocabulary. Unpredicted growth from 1 to 8 y of age was also inversely associated with overage for grade (OR range across countries: 0.80–0.84) and positively associated with mathematics achievement (effect-size range: 0.05–0.10), reading comprehension (0.02–0.10), and receptive vocabulary (0.04–0.08). Children who recovered in linear growth had better outcomes than did children who were persistently stunted but were not generally different from children who experienced growth faltering. Conclusions: Improvements in child growth after early faltering might have significant benefits on schooling and cognitive achievement. Hence, although early interventions remain critical, interventions to improve the nutrition of preprimary and early primary school–age children also merit consideration.

Growth faltering and recovery in children aged 1-8 years in four low- and middle-income countries: Young Lives

OBJECTIVE We characterized post-infancy child growth patterns and determined the incidence of becoming stunted and of recovery from stunting. DESIGN Data came from Young Lives, a longitudinal study of childhood poverty in four low- and middle-income countries. SETTING We analysed length/height measurements for children at ages 1, 5 and 8 years. SUBJECTS Children (n 7171) in Ethiopia, India, Peru and Vietnam. RESULTS Mean height-for-age Z-score (HAZ) at age 1 year ranged from -1·51 (Ethiopia) to -1·08 (Vietnam). From age 1 to 5 years, mean HAZ increased by 0·27 in Ethiopia (P < 0·001) and decreased among the other cohorts (range: -0·19 (Peru) to -0·32 (India); all P < 0·001). From 5 to 8 years, mean HAZ increased in all cohorts (range: 0·19 (India) to 0·38 (Peru); all P < 0·001). Prevalence of stunting (HAZ<-2·0) at 1 year ranged from 21 % (Vietnam) to 46 % (Ethiopia). From age 1 to 5 years, stunting prevalence decreased by 15·1 percentage points in Ethiopia (P < 0·001) and increased in the other cohorts (range: 3·0 percentage points (Vietnam) to 5·3 percentage points (India); all P ≤ 0·001). From 5 to 8 years, stunting prevalence decreased in all cohorts (range: 5·0 percentage points (Vietnam) to 12·7 percentage points (Peru); all P < 0·001). The incidence of becoming stunted between ages 1 to 5 years ranged from 11 % (Vietnam) to 22 % (India); between ages 5 to 8 years, it ranged from 3 % (Peru) to 6 % (India and Ethiopia). The incidence of recovery from stunting between ages 1 and 5 years ranged from 27 % (Vietnam) to 53 % (Ethiopia); between ages 5 and 8 years, it ranged from 30 % (India) to 47 % (Ethiopia). CONCLUSIONS We found substantial recovery from early stunting among children in four low- and middle-income countries.

Height-for-age z scores increase despite increasing height deficits among children in 5 developing countries

BACKGROUND Growth failure remains a persistent challenge in many countries, and understanding child growth patterns is critical to the development of appropriate interventions and their evaluation. The interpretation of changes in mean height-for-age z scores (HAZs) over time to define catch-up growth has been a subject of debate. Most studies of child growth have been cross-sectional or have focused on children through age 5 y. OBJECTIVE The aim was to characterize patterns of linear growth among individuals followed from birth into adulthood. DESIGN We compared HAZs and difference in height (cm) from the WHO reference median at birth, 12 mo, 24 mo, mid-childhood, and adulthood for 5287 individuals from birth cohorts in Brazil, Guatemala, India, the Philippines, and South Africa. RESULTS Mean HAZs were <0 at birth in the 3 cohorts with data and ranged from -0.6 (Brazil) to -2.9 (Guatemala) at age 24 mo. Between 24 mo and mid-childhood, HAZ values increased by 0.3-0.5 in South Africa, Guatemala, and the Philippines and were unchanged in Brazil and India. Between mid-childhood and adulthood, mean HAZs increased in all cohorts but remained <0 in adulthood [mean range: -0.3 (Brazil) to -1.8 (Guatemala and Philippines)]. However, from 24 mo to adulthood, height differences from the reference median became greater. CONCLUSIONS From age 2 y to adulthood, mean HAZs increased, even though height deficits relative to the reference median also increased. These 2 metrics may result in different interpretations of the potential for and the impact of catch-up growth in height.

The sugar-sweetened beverage wars: public health and the role of the beverage industry.

Purpose of reviewTo discuss the current data on sugar-sweetened beverage (SSB) consumption trends, evidence of the health impact, and the role of industry in efforts to reduce the consumption. Recent findingsPreviously rising SSB consumption rates have declined recently, but continue to contribute added sugars beyond the limit advised by the American Heart Association. A recent meta-analysis concluded that SSBs likely increase body weight and recent long-term studies support the previous findings of increased risk of diabetes, dyslipidemia, and hypertension. Beverage companies have played an active role in some SSB reduction efforts by reducing the sale of SSBs in schools, limiting television advertising to children, and increasing the availability of smaller portion-size options. Industry has opposed efforts to restrict the availability of large portion sizes and implement an excise tax. Current industry efforts include the promotion of alternative beverages perceived to be healthier as well as SSBs through Internet and social media. SummaryContinuing high SSB consumption and associated health risks highlight the need for further public health action. The beverage industry has supported some efforts to reduce the consumption of full sugar beverages, but has actively opposed others. The impact of industry efforts to promote beverage alternatives perceived as healthier is unknown.

Sex differences in obesity incidence: 20-year prospective cohort in South Africa

Prospective data spanning childhood and adolescence are needed to better understand obesity incidence among children and to identify important periods for intervention.

Pubertal Development and Prepubertal Height and Weight Jointly Predict Young Adult Height and Body Mass Index in a Prospective Study in South Africa

Background: Height and adiposity track over childhood, but few studies, to our knowledge, have longitudinally examined the mediating relation of the timing and progression of puberty. Objective: We assessed interrelations between prepubertal height and body mass index, the progression through puberty, and young adult height and adiposity. Methods: We analyzed data from the Birth to Twenty Plus study (females, n = 823; males, n = 765). Serial measures of anthropometry and pubertal development were obtained between ages 9 and 16 y. We used latent class growth analysis to categorize pubertal development with respect to pubic hair (females and males), breasts (females), and genitalia (males) development. Adult height and weight were obtained at ages 18 to 20 y. Results: Among females, higher latent class (earlier initiation and faster progression through puberty) was associated with an increased risk of obesity [pubic hair class 3 compared with class 1: RR, 3.41 (95% CI: 1.57, 7.44)] and inconsistent associations with height. Among males, higher latent class was associated with increased adult height [pubic hair development class 3 compared with class 1: 2.43 cm (95% CI: 0.88, 4.00)] and increased risk of overweight/obesity [pubic hair development class 3 compared with class 1: OR, 3.44 (95% CI: 1.44, 8.20)]. In females, the association with adult height became inverse after adjusting for prepubertal height [pubic hair development class 3 compared with class 1: females, −1.31 cm (95% CI: −2.32, −0.31)]; in males, the association with height was attenuated with this adjustment [−0.56 cm (95% CI: −1.63, 0.52)]. Associations with adiposity were attenuated after adjusting for prepubertal adiposity. Conclusions: Progression through puberty modifies the relation between prepubertal and adult anthropometry. Screening for early or rapid progression of puberty might identify children at an increased risk of becoming overweight or obese adults.

Adolescent Pregnancy and Attained Height among Black South African Girls: Matched-Pair Prospective Study

Importance The impact of adolescent pregnancy on offspring birth outcomes has been widely studied, but less is known about its impact on the growth of the young mother herself. Objective To determine the association between adolescent pregnancy and attained height. Design Prospective birth cohort study. Setting Cohort members followed from birth to age 20 y in Soweto, South Africa. Participant From among 840 Black females with sufficient data, we identified 54 matched pairs, in which a girl who became pregnant before the age of 17 years was matched with a girl who did not have a pregnancy by age 20 y. Pairs were matched on age at menarche and height-for-age z scores in the year before the case became pregnant (mean 15.0 y). Main Outcome Measures The two groups were compared with respect to attained height, measured at mean age 18.5 y. Results Mean age at conception was 15.9 years (range: 13.7 to 16.9 y). Mean height at matching was 159.4 cm in the adolescent pregnancy group and 159.3 cm in the comparison group (p = 0.3). Mean attained height was 160.4 cm in the adolescent pregnancy group and 160.3 cm in the comparison group (p = 0.7). Conclusions Among Black females in Soweto, South Africa, adolescent pregnancy was not associated with attained height.