Exposure to Chinese famine in early life and height across 2 generations: a longitudinal study based on the China Health and Nutrition Survey.

BACKGROUND

Poor nutrition early in life is associated with short stature, which is associated with increased risk of cardiovascular disease and mortality in later life. Less evidence is available about the impact of early-life nutrition on height growth in the subsequent generation.

OBJECTIVES

This study investigated the associations of famine exposure in utero and early childhood with height across 2 generations.

METHODS

We used longitudinal data from the China Health and Nutrition Survey. We included 5401 participants (F1) born in 1955-1966 (calendar year around the Chinese famine in 1959-1961) and their 3930 biological offspring (F2). We classified F1 participants into subgroups by famine exposure status (unexposed/exposed) and timing (fetal-/childhood-exposed) according to their birth year and grouped F2 by their parents' exposure. Linear regression models were applied to examine the associations of famine exposure with adult height of F1 and F2. Linear mixed effect models with fractional polynomial functions were performed to estimate the difference in height between exposure groups of F2 during childhood.

RESULTS

Participants (F1) exposed to famine in utero or in childhood were shorter than those unexposed by 0.41 cm (95% CI: 0.03, 0.80) and 1.12 cm (95% CI: 0.75, 1.48), respectively. Offspring (F2) of exposed fathers were also shorter than those of unexposed parents by 1.07 cm (95% CI: 0.28, 1.86) during childhood (<18 y) and by 1.25 cm (95% CI: 0.07, 2.43) in adulthood (≥18 y), and those with exposed parents had a reduced height during childhood by 1.29 cm (95% CI: 0.68, 1.89) (all P values < 0.05). The associations were more pronounced among child offspring of highly-educated F1, particularly for paternal exposure and among female offspring (all P for interaction < 0.05).

CONCLUSIONS

The findings support the intergenerational associations of famine exposure in early life with height in Chinese populations, indicating the public health significance of improving the nutritional status of mothers and children in the long run.