VATERL - AN EPIDEMIOLOGIC ANALYSIS OF RISK-FACTORS

This work analyzed the incidence of risk factors in 138 cases presenti ng two or more of five components defining VATERL, with no other recog nized unrelated anomalies: vertebral anomalies, anal atresia, esophage al atresia with or without tracheoesophageal fistula, renal anomalies, and preaxial defects of the upper limbs, including polydactyly of the thumb. The 138 infants were ascertained among 1,811,461 births examin ed in the 1967-1994 period by the Latin-American Collaborative Study o f Congenital Malformations: ECLAMC. One healthy and one malformed cont rol newborn infant were matched to each VATERL case. The birth prevale nce rates (per 100,000 births) for VATERL were significantly lower in Venezuela (3.1) than in the other eight countries (8.8) (P < 0.001). V enezuela also had lower rates for all five VATERL defects, even after excluding the 138 VATERL cases. VATERL cases were preferentially males (male proportion 0.6261) (P < 0.02), and, when compared with healthy controls, they had a higher perinatal mortality rate (63.7%) (P < 0.00 5), a higher frequency of fetal losses in previous pregnancies (12.6%) (P < 0.05), and lower mean birthweights (2,361.79 +/- 809.63 g) (P < 0.005). VATERL cases showed a higher rate than matched malformed contr ols for prenatal exposures to drugs and physical agents (P < 0.02 and P < 0.05, respectively), although no specific pharmacological or physi cal group was involved. The lower birth prevalence rates found in Vene zuela, for VATERL as well as for each of the five congenital anomalies involved in this association, seem to be biologically meaningful. Sin ce we could not identify a potential risk factor, nor a common cause o f underascertainment unique to the Venezuelan subsample and common to all six hospitals, no hypothesis can be advanced here for this phenome non. Nevertheless, this unequal geographic distribution strongly sugge sts a common etiopathogenicity for the five congenital anomalies invol ved in the VATERL association. (C) 1997 Wiley-Liss, Inc.