BACKGROUND

Intravenous atropine therapy (IAT) is feasible for infantile hypertrophic pyloric stenosis (IHPS). Currently, IAT is recommended for only patients with risks against surgery. However, reported proportions of successful IAT ranged widely, being from 70 to 90%. Factors related to successful IAT remain unknown. This study aimed to identify predictive factors of successful IAT for IHPS using a national inpatient database in Japan.

METHODS

Using the Diagnosis Procedure Combination database, we identified children with IHPS from July 2010 to March 2016. We compared patients’ characteristics between the IAT and surgery groups, and between the successful and unsuccessful IAT groups. Multivariable logistic regression analysis was performed for successful IAT.

RESULTS

We identified 1,822 eligible patients (526 IAT patients). IAT had a success rate of 73.4% (n = 386) and 140 unsuccessful patients subsequently underwent surgery. Body weight at admission in the successful group was significantly heavier than that in the unsuccessful group. The Multivariate logistic analysis showed that the proportion of successful IATs was significantly higher in the heavy weight (4,000–4,999 g) (odds ratio, 2.03; 95% confidence interval, 1.32–3.13) and very heavy weight (≥5,000 g) groups (odds ratio, 5.35; 95% confidence interval, 1.80–15.9) than in the middle weight (3,000–3,999 g) group.

CONCLUSIONS

Heavier body weight was associated with successful IAT. These results are useful for patients select therapeutic options for IHPS, including surgery and IAT.