Differences in body mass index z-scores and weight status in a Dutch pediatric psychiatric population with and without use of second-generation antipsychotics.

Objective: Weight gain and metabolic adverse effects of second-generation antipsychotics (SGAs) have become a major concern, particularly in youth. However, the specific contribution of SGAs versus other medications or the underlying illness is unclear.

Methods: In a chart review study of psychiatric outpatients aged ≤ 18 years treated with SGAs and psychiatric controls without lifetime SGA, use body mass index (BMI) z-scores between patients and controls were compared in the entire sample, patients without co-medications, diagnostic subgroups, and age subgroups. In patients with follow-up data, weight z-score change was calculated.

Results: Altogether, 592 Caucasian patients aged 4-18 (mean: 10.0) years with a psychiatric diagnosis were included. BMI z-scores in 96 youth treated with SGAs for 9.0 ± 6.1 months were significantly higher than in 496 patients without lifetime SGA use (0.81 ± 1.1 vs. 0.05 ± 1.2; p<0.0001). BMI z-score differences remained significant in all age groups <16 years old. In sub-analyses, results remained the same after eliminating patients on any co-medication (0.82 ± 1.2 vs. 0.23 ± 1.2; p<0.0001) and in patients with (0.75 ± 1.2 vs. 0.17 ± 1.1, p<0.0001) or without autism spectrum disorders (1.1 ± 1.0 vs. -0.02 ± 1.2, p<0.0001). Significantly more SGA-treated youth were obese (27.1% vs. 9.5%, odds ratio [OR]: 3.55, 95% confidence interval [CI]:2.07-6.08) or overweight (21.9% vs. 8.3%, OR: 3.11, 95%CI: 1.75-5.52). In 24 patients (92.3% antipsychotic-naïve) with 6.6 months follow-up, weight z-score increased significantly from -0.17 ± 1.5 to 0.25 ± 1.4 (p<0.0001) with 12.5% transitioning to overweight or obese status.

Conclusion: These data show robust and significant differences in sex- and age-adjusted body weight and weight status in young pediatric Caucasian samples with and without use of SGAs independent of Diagnostic and Statistical Manual of Mental Disorders, 4th edition, Text Revision (DSM-IV-TR) (American Psychiatric Association 2000 ) diagnosis and nonantipsychotic medications. Weight status and metabolic effects of SGAs require careful attention, especially in youth.