#93-S u.s.-mexico cohort study of Helicobacter pylori Infection in children

PURPOSE: Helicobacter pylori infection occurs frequently in early childhood; persistence leads to chronic digestive diseases in adults. The Pasitos Cohort Study follows children from El Paso, Texas, USA and Ciudad Juarez, Mexico at 6-month intervals to identify predictors of acquisition and persistence of H. pylori infection. METHODS: Pregnant women were recruited from El Paso WIC clinics and Mexican Social Security Institute maternal-child clinics in Juarez from April 1998 to October 2000. Active H. pylori infection is detected in children by the 13C-urea breath test; results are corrected for body-size-dependent metabolic variation using Kleinʹs method. RESULTS: The seroprevalence of H. pylori at baseline was 74% in 360 Juarez mothers and 56% in 368 El Paso mothers. To date, 350, 295, 196, 153 infants had breath tests around 6, 12, 18, and 24 months of age, respectively; H. pylori prevalence in the children was 0.07 [95% Confidence interval (CI) 0.05–0.10], 0.14, [0.11–0.19], 0.17 [0.12–0.23], and 0.20 [0.14–0.27] for these four ages, respectively. The total follow-up time was 6181 person-months; 108 infants had one or more positive breath tests, thus, the incidence rate of first detectable infection was 0.21/year [95% CI, 0.17–0.25]. Incidence rates for subgroups: Juarez infants, 44/2260 PERSON-MONTHS = 0.23/year [0.16–0.30]; El Paso infants, 64/3921 PERSON-MONTHS = 0.20/year [0.15–0.24]; boys, 49/2976 PERSON-MONTHS = 0.20/year [0.14–0.25]; girls, 59/3205 PERSON-MONTHS = 0.22/year [0.16–0.28]; first year of age, 66/4243 PERSON-MONTHS = 0.19/year [0.14–0.23]; second year of age, 31/1340 PERSON-MONTHS = 0.28/year [0.18–0.38]. CONCLUSION: H. pylori incidence rate from birth through age two years was similar in infants on both sides of the U.S.-Mexico border and varied little by sex; the rate increased in the second year of life relative to the first.