The results of a literature review published in Bipolar Disorders suggest that subthreshold pediatric bipolar disorder is associated with substantial psychiatric impairments and high suicidality.
Investigators performed a literature search through PubMed in November 2017 for studies on full and subthreshold bipolar disorder in youths (≤18 years). To be selected for inclusion, studies had to report functional outcomes. Two psychiatrists and a research assistant individually screened articles for eligibility. A total of 5 domains of illness morbidity were examined: functional impairment, mood symptomatology, psychiatric comorbidity, suicidality, and use of mental health services. For each of these domains, meta-analysis was performed to compare patients with subthreshold pediatric bipolar disorder and patients with full threshold pediatric bipolar disorder type I. Pooled standardized mean difference (SMD) and pooled risk ratio (RR) values were computed for continuous and binary measures, respectively.
The literature search identified 45 relevant articles, among which 11 were used in subsequent analyses. The meta-analyses compared patients with subthreshold pediatric bipolar disorder (n=244) with nonbipolar disorder control participants (n=1125), as well as patients with subthreshold pediatric bipolar disorder (n=643) with patients with pediatric bipolar disorder type I (n=942). Subthreshold pediatric bipolar disorder was associated with greater functional impairment (SMD, 0.61; 95% CI, 0.25-0.97); greater severity of mania (SMD, 1.88; 95% CI, 1.38-2.38) and depression (SMD, 0.66; 95% CI, 0.52-0.80); higher rates of disruptive behavior (RR, 1.75; 95% CI, 1.17-2.62), mood (RR, 1.78; 95% CI, 1.29-2.79), and substance use (RR, 2.27; 95% CI, 1.23-4.21) disorders; and higher rates of suicidal ideation and attempts (RR, 7.66; 95% CI, 1.71-34.33) compared with control participants. Pediatric bipolar disorder type I was associated with greater functional impairment (SMD 0.61; 95% CI, 0.25-0.97), greater severity of manic symptoms (SMD 0.55; 95% CI, 0.14-0.95), higher rates of suicidal ideation and attempts (RR, 1.62; 95% CI, 1.04-2.52), and higher rates of mental health treatment (RR, 1.91; 95% CI, 1.09-3.35) compared with subthreshold pediatric bipolar disorder; however, no differences in severity of depressive symptoms or rates of comorbid disorders were observed between full and subthreshold cases.
These data indicated that subthreshold pediatric bipolar disorder still presents a significant psychiatric and functional burden. Physicians should take care to accommodate young patients who may not meet the full criteria for pediatric bipolar disorder.
Vaudreuil CAH, Faraone SV, Di Salvo M, et al. The morbidity of subthreshold pediatric bipolar disorder: a systematic literature review and meta-analysis [published online November 27, 2018]. Bipolar Disord. doi: 10.1111/bdi.12734