Evaluation of Linear Growth at Higher Altitudes

Area of Science:

• Pediatric Growth and Development
• Environmental Health
• Global Health Disparities

Background:

• Children's growth potential is generally similar irrespective of genetics, provided an ideal home environment.
• However, the impact of high-altitude living on child growth remains under-investigated.

Purpose of the Study:

• To determine if higher altitudes are associated with increased linear growth faltering in children.
• To assess the applicability of 2006 World Health Organization (WHO) growth standards for populations above 1500m.

Main Methods:

• Analysis of 133 nationally representative Demographic and Health Surveys (DHS) from 59 low- and middle-income countries (1992-2018).
• Included 964,299 height records from 96,552 clusters across altitudes ranging from -372m to 5951m.
• Utilized local polynomial and multivariate regression to assess altitude-related height deficits.

Main Results:

• Children residing above 1500m had shorter birth lengths and lower growth trajectories compared to those below 1500m.
• A 1000m increase in altitude correlated with a 0.163-unit decrease in height-for-age z scores (HAZ).
• WHO growth standards showed similarity to ideal home environment data only up to 500m altitude.

Conclusions:

• Higher altitude living is associated with reduced child linear growth, even in optimal home environments.
• Altitude-mediated growth restrictions may occur during pregnancy and early childhood.
• Further research and interventions are needed to address altitude-specific growth challenges.