Waist Circumference is a Sensitive Screening Tool for Assessment of Metabolic Syndrome Risk in Children Treated with Second-Generation Antipsychotics

Abstract

To compare the prevalence of metabolic syndrome (MetS) and its components in second-generation antipsychotic (SGA)-treated and SGA-naive children; and to explore the utility of clinical markers, such as waist circumference (WC) and body mass index (BMI), as screening tools for MetS. Subjects were prospectively recruited from the Psychiatry Emergency Unit at British Columbia Children's Hospital. As part of a quality-assurance project, a metabolic monitoring protocol was implemented, including collection of anthropomorphic and laboratory data. From January 2008 to February 2010, there were 117 SGA-treated and 217 SGA-naive children recruited. The overall prevalence of MetS was 19.0% (16/84; median treatment duration = 14 months) in SGA-treated and 0.8% (1/127) in SGA-naive children (OR 29.7; 95% CI 3.85 to 228.40, P < 0.001), with an increased prevalence of all components except high-density lipoprotein cholesterol (HDL-C), respectively: elevated WC (40.7% and 10.1%; P < 0.001); hypertriglyceridemia (33.7% and 18.8%; P = 0.01); impaired fasting glucose (12.5% and 0.7%; P = 0.005); and elevated blood pressure (41.2% and 16.5%; P < 0.001). SGA treatment was the strongest predictor of MetS (OR 19.2; 95% CI 2.30 to 160.44, P = 0.006) followed by male sex (OR 5.7; 95% CI 1.08 to 30.62, P = 0.04). Presence of abdominal obesity was more sensitive (92.9%) than BMI (68.8%), while fasting glucose of 5.6 mmol/L or more and HDL-C of 1.03 mmol/L or less were most specific (94.1%) in correctly identifying MetS. SGA treatment confers a significantly increased risk for MetS over the long term. WC measurement is a simple and sensitive screening tool for determining MetS risk in SGA-treated children. These data highlight the dangers of SGA treatment and the importance of standardized metabolic monitoring using sex- and age-adjusted tables in this population.