To assess rates of conversion to bipolar spectrum disorder (BPSD) and risk factors associated with conversion in children with depressive spectrum disorders (DSD) and transient manic symptoms (TMS) over 18 months. TMS are manic-like symptoms of insufficient duration or number to warrant a diagnosis of BPSD. Participants were 165 children (mean = 9.9 years, SD = 1.3) with mood disorders from the Multi-Family Psychoeducational Psychotherapy (MF-PEP) treatment study: 37 with DSD+TMS, 13 with DSD, and 115 with BPSD. All were assessed with standardized instruments on four occasions over 18 months, with half receiving MF-PEP after their baseline assessment and half receiving MF-PEP after a one-year wait-list condition. At baseline, the Children's Global Assessment Scale scores did not differ significantly between the DSD+TMS, DSD, and BPSD groups. Conversion rates to BPSD were significantly higher for the DSD+TMS group (48.0%) compared to the DSD group (12.5%). Conversion was significantly more frequent for participants in the one-year wait-list control group (60%) compared to the immediate treatment group (16%). Clinical presentation, family environment, and family history did not differ significantly between the small subset of DSD+TMS participants who did convert to BPSD at follow-up and those who did not convert. Baseline functional impairment was greater for the converted group than the non-converted group. Transient manic symptoms are a risk factor for eventual conversion to BPSD; psychoeducational psychotherapy may be protective. As this exploratory study had a small sample size and did not correct for multiple comparisons, additional studies with larger sample sizes are needed. (c) 2010 John Wiley & Sons A/S.
