Response to Comment on Beltrand et al. Sulfonylurea Therapy Benefits Neurological and Psychomotor Functions in Patients With Neonatal Diabetes Owing to Potassium Channel Mutations. Diabetes Care 2015;38:2033–2041
We would like to respond to the comment made by Beltrand et al. (1). In our study (2), we hypothesized that a successful switch from insulin to sulfonylurea therapy in patients with neonatal diabetes owing to KATP channel mutations would improve neurodevelopmental parameters. It was a prospective single-center cohort study of patients switched from insulin to sulfonylurea therapy. The inclusion criterion was neonatal diabetes owing to a mutation in the KCNJ11 or ABCC8 gene. We did not anticipate the neuropsychological changes caused by the mutation and included all of our patients in a prospective way independently of the mutation as stated by the protocol. Because of the small sample size and the heterogeneity of the study population in terms of genetic results, statistical analysis failed to find any relationship between the mutation and the developmental assessment findings before and after the switch. However, this was not stated as a primary end point of the study, and the small population size did not have the statistical power to reach this outcome.
Our interpretations of the results are based on well-conducted statistical analysis. Furthermore, the reader can find as Supplementary Data the results for each patient and a complete description of the NP-MOT (French Neuromotor Functions in Children) battery test and interpretation of its results. The reader can therefore have a detailed view of the results for each patient.
Finally, the patient with the V59M mutation included in our study was one of the oldest patients and had the most altered developmental parameters. The switch from insulin to sulfonylurea therapy occurred at an older age than in the case reports (3,4) cited by Beltrand et al. As we found that the improvement was better when the switch was made earlier in life, the result in this particular patient (the one included in our study, older than the one in the case report) does not change the global results. Findings from isolated case reports can be the basis for discussions or the start of well-conducted clinical trials but cannot be compared with findings from clinical studies.
Duality of Interest. The authors have collaborated for several years with Vaxillaire et al. in the area of neonatal diabetes. No other potential conflicts of interest relevant to this article were reported.
- © 2016 by the American Diabetes Association.
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