Early-life nutritional and environmental determinants of thymic size in infants born in rural Bangladesh.
OBJECTIVE
The aim was to assess the impact of nutritional status and environmental exposures on infant thymic development in the rural Matlab region of Bangladesh.


METHODS
In a cohort of N(max) 2094 infants born during a randomized study of combined interventions to improve maternal and infant health, thymic volume (thymic index, TI) was assessed by ultrasonography at birth and at 8, 24 and 52 weeks of age. Data on birth weight, infant anthropometry and feeding status were also collected.


RESULTS
At all ages, TI was positively associated with infant weight and strongly associated with the month of measurement. Longer duration of exclusive breastfeeding resulted in a larger TI at 52 weeks. TI at birth and at 8 weeks correlated positively with birth weight, but by 24 and 52 weeks and when adjusted for infant weight this effect was no longer present. Thymic size was not affected by pre-natal maternal supplementation or by socioeconomic status but was correlated to arsenic exposure during pregnancy.


CONCLUSIONS
In this population of rural Bangladeshi infants, thymic development is influenced by both nutritional and environmental exposures early in life. The long-term functional implications of these findings warrant further investigation.
Moore
Sophie E
SE
MRC Keneba, MRC Laboratories, Banju, The Gambia. Sophie.Moore@lshtm.ac.uk
Prentice
A M
AM
Wagatsuma
Y
Y
Fulford
A J C
AJ
Collinson
A C
AC
Raqib
R
R
Vahter
M
M
Persson
L A
LA
Arifeen
S E
SE
D000704:Analysis of Variance; D001151:Arsenic / Q000652:urine; D001459:Bangladesh; D001835:Body Weight; D001942:Breast Feeding; D002657:Child Development / Q000502:physiology*; D019587:Dietary Supplements; D004781:Environmental Exposure; D005260:Female; D006293:Health Promotion / Q000379:methods; D006801:Humans; D007223:Infant; D007227:Infant Nutritional Physiological Phenomena; D007231:Infant, Newborn; D018811:Maternal Exposure; D039382:Maternal Nutritional Physiological Phenomena; D009752:Nutritional Status; D009929:Organ Size; D011247:Pregnancy; D012044:Regression Analysis; D012423:Rural Health; D012621:Seasons; D013950:Thymus Gland / Q000000981:diagnostic imaging / Q000254:growth & development*; D014463:Ultrasonography
D001151:Arsenic