Categorical and dimensional psychopathology in Dutch and US offspring of parents with bipolar disorder: A preliminary cross-national comparison

Abstract

Objective Accumulating evidence suggests cross-national differences in adults with bipolar disorder (BD), but also in the susceptibility of their offspring (bipolar offspring). This study aims to explore and clarify cross-national variation in the prevalence of categorical and dimensional psychopathology between bipolar offspring in the US and The Netherlands. Methods We compared levels of psychopathology in offspring of the Pittsburgh Bipolar Offspring Study (n=224) and the Dutch Bipolar Offspring Study (n=136) (age 10–18). Categorical psychopathology was ascertained through interviews using the Schedule for Affective Disorders and Schizophrenia for School Age Children (K-SADS-PL), dimensional psychopathology by parental reports using the Child Behavior Checklist (CBCL). Results Higher rates of categorical psychopathology were observed in the US versus the Dutch samples (66% versus 44%). We found no differences in the overall prevalence of mood disorders, including BD-I or -II, but more comorbidity in mood disorders in US versus Dutch offspring (80% versus 34%). The strongest predictors of categorical psychopathology were maternal BD (OR: 1.72, p<.05), older age of the offspring (OR: 1.19, p<.05), and country of origin (US; OR: 2.17, p<.001). Regarding comorbidity, only country of origin (OR: 7.84, p<.001) was a significant predictor. In general, we found no differences in dimensional psychopathology based on CBCL reports. Limitations Preliminary measure of inter-site reliability. Conclusions We found cross-national differences in prevalence of categorical diagnoses of non-mood disorders in bipolar offspring, but not in mood disorder diagnoses nor in parent-reported dimensional psychopathology. Cross-national variation was only partially explained by between-sample differences. Cultural and methodological explanations for these findings warrant further study.

Debate: No bipolar disorder in prepubertal children at high familial risk

“…However, cross‐national variation is an issue with BD‐NOS, as studies show more variation when BD‐NOS is included as a result of different methods, interpretation of criteria, and prevalence rates across countries. This was also the case in our study comparing categorical and dimensional psychopathology from the Pittsburg BIOS study and the Dutch Bipolar Offspring Study (Mesman et al., ). BD‐NOS prevalence rate in the Pittsburgh sample was high (6.7%), but was not assessed in Dutch offspring because of unclear criteria and could therefore not be compared directly.…”

The International Society for Bipolar Disorders Task Force report on pediatric bipolar disorder: Knowledge to date and directions for future research

“…50 Both projects used the Achenbach Child Behavior Checklist (CBCL) 51 as well as similar semi-structured interviews (eg, the Kiddie Schedule for Affective Disorders and Schizophrenia). 52 After controlling for age, rates of DSM-IV BD-I (2.2% in the US sample and 1.5% in the Dutch sample) and BD-II (2% and 1%, respectively) were similar.…”

“…Translating scales into multiple languages and pursuing cross-cultural validation are accelerating progress by using consistent definitions, 50 revealing considerable continuity in phenomenology. 53 Combining data sets internationally would help calibrate definitions and examine common risk factors.…”

Progress in diagnosis and treatment of bipolar disorder among children and adolescents: an international perspective

“…Other studies have found childhood-onset of BPD to be associated with other pernicious outcomes including increased irritability, mood lability, worse severity and course of illness, psychotic symptoms, worse response to lithium and increased risk for comorbid diagnoses and suicidality25 (w12–14). Studies comparing the USA to European countries demonstrate an earlier age of onset among US samples than European samples12 (w15). Reasons for differing ages of onset are yet unclear.…”