Neuropsychological study of IQ scores in offspring of parents with bipolar I disorder

ABSTRACT

Introduction: Studies comparing IQ in Offspring of Bipolar Parents (OBP) with Offspring of Healthy Controls (OHC) have reported conflicting findings. They have included OBP with mental health/neurodevelopmental disorders and/or pharmacological treatment which could affect results. This UK study aimed to assess IQ in OBP with no mental health/neurodevelopmental disorder and assess the relationship of sociodemographic variables with IQ.

Methods: IQ data using the Wechsler Abbreviated Scale of Intelligence (WASI) from 24 OBP and 34 OHC from the North East of England was analysed using mixed-effects modelling.

Results: All participants had IQ in the average range. OBP differed statistically significantly from OHC on Full Scale IQ (p = .001), Performance IQ (PIQ) (p = .003) and Verbal IQ (VIQ) (p = .001) but not on the PIQ-VIQ split. OBP and OHC groups did not differ on socio-economic status (SES) and gender. SES made a statistically significant contribution to the variance of IQ scores (p = .001).

Conclusions: Using a robust statistical model of analysis, the OBP with no current/past history of mental health/neurodevelopmental disorders had lower IQ scores compared to OHC. This finding should be borne in mind when assessing and recommending interventions for OBP.

KEYWORDS:

• Bipolar disorder
• offspring
• IQ
• socio-economic status

Disclosure statement

Prof Heinz Grunze has been in receipt of honoraria or consultation fees from: Gedeon-Richter, Lundbeck, Hofmann-LaRoche and has participated in company sponsored speaker’s bureau for: BMS, Ferrer, Janssen-Cilag, Otsuka, Lundbeck, Pfizer.

Additional information

Funding

The project was funded by the Research and Clinical Effectiveness Department, Northumberland Tyne and Wear NHS Foundation Trust, UK and Mental Health Foundation, North East Branch, UK.