RESUMEN
Antipsychotics are used for many psychiatric conditions in youth. Although developmentally inappropriate weight gain and metabolic abnormalities, which are risk factors for premature cardiovascular mortality, are especially frequent in youth, optimal strategies to reduce pediatric antipsychotic-induced overweight/obesity are unclear. The Improving Metabolic Parameters in Antipsychotic Child Treatment (IMPACT) was a randomized, parallel group, 24-week clinical trial which enrolled overweight/obese, psychiatrically stable youth, aged 8-19 years, with a DSM-IV diagnosis of severe mental illness (schizophrenia spectrum disorder, bipolar spectrum disorder or psychotic depression), at four US universities. All of them had developed substantial weight gain following treatment with a second-generation antipsychotic. The centralized, computer-based randomization system assigned participants to unmasked treatment groups: metformin (MET); antipsychotic switch (aripiprazole or, if already exposed to that drug, perphenazine or molindone; SWITCH); or continued baseline antipsychotic (CONTROL). All participants received healthy lifestyle education. The primary outcome was body mass index (BMI) z-score change from baseline, analyzed using estimated least squares means. Altogether, 127 participants were randomized: 49 to MET, 31 to SWITCH, and 47 to CONTROL. BMI z-score decreased significantly with MET (week 24: -0.09±0.03, p=0.002) and SWITCH (week 24: -0.11±0.04, p=0.003), while it increased non-significantly with CONTROL (week 24: +0.04±0.03). On 3-way comparison, BMI z-score changes differed significantly (p=0.001). MET and SWITCH were each superior to CONTROL (p=0.002), with effect sizes of 0.68 and 0.81 respectively, while MET and SWITCH did not differ. More gastrointestinal problems occurred in MET than in SWITCH or CONTROL. The data safety monitoring board closed the perphenazine-SWITCH arm because 35.2% of subjects discontinued treatment due to psychiatric worsening. These data suggest that pediatric antipsychotic-related overweight/obesity can be reduced by adding metformin or switching to a lower risk antipsychotic. Healthy lifestyle education is not sufficient to prevent ongoing BMI z-score increase.
RESUMEN
BACKGROUND: Youth with serious mental illness may experience improved psychiatric stability with second generation antipsychotic (SGA) medication treatment, but unfortunately may also experience unhealthy weight gain adverse events. Research on weight loss strategies for youth who require ongoing antipsychotic treatment is quite limited. The purpose of this paper is to present the design, methods, and rationale of the Improving Metabolic Parameters in Antipsychotic Child Treatment (IMPACT) study, a federally funded, randomized trial comparing two pharmacologic strategies against a control condition to manage SGA-related weight gain. METHODS: The design and methodology considerations of the IMPACT trial are described and embedded in a description of health risks associated with antipsychotic-related weight gain and the limitations of currently available research. RESULTS: The IMPACT study is a 4-site, six month, randomized, open-label, clinical trial of overweight/obese youth ages 8-19 years with pediatric schizophrenia-spectrum and bipolar-spectrum disorders, psychotic or non-psychotic major depressive disorder, or irritability associated with autistic disorder. Youth who have experienced clinically significant weight gain during antipsychotic treatment in the past 3 years are randomized to either (1) switch antipsychotic plus healthy lifestyle education (HLE); (2) add metformin plus HLE; or (3) HLE with no medication change. The primary aim is to compare weight change (body mass index z-scores) for each pharmacologic intervention with the control condition. Key secondary assessments include percentage body fat, insulin resistance, lipid profile, psychiatric symptom stability (monitored independently by the pharmacotherapist and a blinded evaluator), and all-cause and specific cause discontinuation. This study is ongoing, and the targeted sample size is 132 youth. CONCLUSION: Antipsychotic-related weight gain is an important public health issue for youth requiring ongoing antipsychotic treatment to maintain psychiatric stability. The IMPACT study provides a model for pediatric research on adverse event management using state-of-the art methods. The results of this study will provide needed data on risks and benefits of two pharmacologic interventions that are already being used in pediatric clinical settings but that have not yet been compared directly in randomized trials. TRIAL REGISTRATION: Clinical Trials.gov NCT00806234.
RESUMEN
Eighty-five adolescents (ages 13 to 17), recruited from various metropolitan pediatric outpatient clinics, were administered the Patient Health Questionnaire (PHQ)-2, a two-item depression screener, along with two other well-established measures of depression, the Children's Depression Inventory (CDI) and the Beck Depression Inventory (BDI). Results indicated a significant relationship between the second question of the PHQ-2 and the two established measures of depression. Discriminant function analysis revealed that classification of adolescents as depressed or not depressed on the basis of their responses to this second question resulted in correct classification of 73% of adolescents with a sensitivity of 0.48 and specificity of 0.60. The use of both questions resulted in lower classification accuracy (67%) but a higher sensitivity of 0.85 and a slightly lower specificity of 0.51 than either question alone. These results support the use of this measure as a brief screener for adolescent depression in primary care.