Natural History and Familial Relationships of Infant Spilling to 9 Years of Age

Objectives. To determine the natural history of infant spilling (regurgitation/vomiting) during the first 2 years of life and to determine the relationship between infant spilling and gastroesophageal reflux (GER) symptoms at 9 years of age. Methods. A prospective birth cohort was followed with daily symptom diaries during the first 2 years of life and reviewed at 9 years of age (range: 8–11 years). The prevalence of infant spilling during the first 2 years of life, the prevalence of GER symptoms between 8 and 11 years of age (mean age: 9.7 years), relative risk of infant spilling predisposing to GER symptoms at 9 years of age, and prevalence of maternal GER symptoms and relationship with infant spilling and GER at 9 years of age were measured. Results. A total of 693 children who represented 83% of an original sample of 836 children and were followed for 2 years from birth with daily symptom diaries were contacted at 9 (8–11) years of age. Spilling of most feeds each day was common in infancy and reached a peak prevalence of 41% between 3 and 4 months of age and thereafter declined to < 5% between 13 and 14 months of age. Infants with spilling on 90 days or more during the first 2 years of life (classified as frequent spilling) were more likely to have GER symptoms at 9 years of age. Children with frequent infant spilling, compared with those with no spilling, had a relative risk of 2.3 (95% confidence interval [CI]: 1.3–4.0) of 1 or more GER symptoms at 9 years of age, 4.6 (95% CI: 1.5–13.8) for heartburn, 2.7 (95% CI: 1.4–5.5) for vomiting, and 4.7 (95% CI: 1.6–14.0) for acid regurgitation. Gender, breastfeeding, and environmental tobacco smoke exposure were not significant factors related to infant spilling. Prepregnancy smoking and smoking in the same room as the child at the 9-month and 18-month follow-ups had a significant effect on GER symptoms at 9 years of age. Infant spilling and GER at 9 years of age were significantly related to maternal GER symptoms but not to paternal GER symptoms. Conclusions. Spilling in infancy is very common, but the majority of children settle by 13 to 14 months of age. However, those with frequent spilling (>90 days) are more likely to have GER symptoms at 9 years of age. In addition, a maternal history of GER was significantly related both to infant spilling and to GER at 9 years, suggesting that a genetic component may be involved. Physicians should consider studying children with a history of frequent infant spilling to determine whether this group is at increased risk for GER disease.