Utilization and Predictors of Adjuvant Metformin in Children and Adolescents on Second-Generation Antipsychotics (Mixed Receptor Antagonists).

OBJECTIVE: The objective was to examine the utilization and predictors of adjuvant metformin among pediatric SGA (mixed receptor antagonist) recipients.

METHOD: This study uses 2016 to 2021 data of a national electronic medical record database. Eligible individuals are children aged 6-17 with a new SGA prescription for at least 90 days. Predictors of prescribing adjuvant metformin in general and to non-obese pediatric SGA recipients, in particular, assessed using conditional logistic regression and logistic regression analyses respectively.

RESULTS: Of 30,009 pediatric SGA recipients identified, 2.3% (n=785) received adjuvant metformin. Among the 597 with a BMI z-score documented during the 6-month period prior to metformin initiation, 83% were obese and 34% had either hyperglycemia or diabetes. Significant predictors for metformin prescribing were high baseline BMI z-score (OR, 95%CI: 3.5, 2.8-4.5, p< 0.0001), having hyperglycemia or diabetes (OR, 95%CI: 5.3, 3.4-8.3, p< 0.0001), undergoing a switch from a higher metabolic risk SGA to a lower risk one (OR, 95%CI: 9.9, 3.5-27.5, p= 0.0025), or a switch in the opposite direction (OR, 95%CI: 4.1, 2.1-7.9, p= 0.0051) compared to no switch. Nonobese metformin users were more likely to have a positive BMI z-score velocity before metformin initiation than their obese counterparts. Receiving the index SGA prescribed by a mental health specialist was associated with higher likelihood of receiving adjuvant metformin and receiving metformin before the development of obesity.

CONCLUSION: The utilization of adjuvant metformin among pediatric SGA recipients is uncommon, and the early introduction of the medication among nonobese children is rare.