Urbanisation and vitamin A deficiency in children: comparison between a traditional district and a new settlement in Mali.

OBJECTIVES

The purpose of this study was to assess the vitamin A status of pre-school urban children and to compare the situation between a traditional district and a new settlement after two decades of intense urbanisation.

SUBJECTS AND METHODS

A cross-sectional stratified survey was carried out in Bamako, Mali, on a representative sample of children (aged 4-6 years). 532 children were involved from a traditional district and 453 from a new settlement (NS). The vitamin A status was assessed by: clinical indicators (ophthalmic examination), subclinical indicators (questionnaire looking for night blindness, impression cytology with transfer test (ICT), modified relative dose response test (MRDR), and a diet inquiry about vitamin A intakes. Acute malnutrition was assessed by a weight/height measure.

RESULTS

In both districts, all the clinical indicators were below the WHO criteria that define a public health problem. Both the ICT test, respectively 19 and 21% of abnormal tests, and the MRDR, 67.3 and 73.1% of tests > or = 0.06, indicated a subclinical vitamin A deficiency as defined by WHO thresholds. During the preceding week only four children in NS had consumed vitamin A-rich food less than seven times. No significant difference between the two districts was found either for clinical or subclinical indicators (p > 0.5).

CONCLUSION

Despite a rapid urbanisation, the vitamin A status of the children seemed to be rather homogeneous among the different districts. The population remained vulnerable with peripheral depletion and low hepatic stores of vitamin A. The urban children should be carefully monitored regarding vitamin A status.