Association between affective temperaments and bipolar spectrum disorders: preliminary perspectives from a controlled family study

Affective Temperament Traits Measured by TEMPS-A and Their Associations with Cognitive Functions among Offspring of Parents with Bipolar Disorder with and without Subthreshold Symptoms

BACKGROUND

To our knowledge, there have been no studies that have examined affective temperament traits in offspring of parents with bipolar disorder (BD). The aim of this study was to identify affective temperamental characteristics and their relationships with cognitive functions in BD offspring.

METHODS

A group of BD offspring were enrolled in this study. Subthreshold symptoms were used to categorize participants as either symptomatic offspring (SO) (n=60) or asymptomatic offspring (AO) (n=52). Healthy controls (HCs; n=48) were also enrolled for comparison. We used the Chinese Short Version of Temperament Evaluation of Memphis, Pisa, Paris, and San Diego, Auto-questionnaire (TEMPS-A) to measure temperament traits, and MATRICS Consensus Cognitive Battery (MCCB) to measure cognitive functions.

RESULTS

We observed higher cyclothymic, irritable, depressive and anxious temperament scores in SO than AO when compared to HCs. In BD offspring (SO and AO), cyclothymic individuals performed better in processing speed and verbal learning than depressive individuals and better in attention/vigilance than irritable and anxious individuals; hyperthymic individuals performed better in processing speed than depressive individuals. We also observed that a higher cyclothymic score was associated with better verbal learning and verbal fluency, a higher hyperthymic score was associated with better processing speed and verbal learning; while a higher depressive score was associated with worse processing speed, verbal learning and verbal fluency and a higher irritable score was associated with worse attention/vigilance.

CONCLUSIONS

The relationships between cognitive functions and measures of temperament suggest that these features may share neurobiological substrates and appear to be heritable.

A Transdisciplinary Integrative Approach for Precision Psychiatry

Theoretical psychiatry considers theoretical problems in psychiatry as well as the quality and effectiveness of mental health care. This chapter addresses the idea of predictive, preventive, precision, personalized, and participatory medicine in psychiatry from a theoretical transdisciplinary integrative perspective and systems networking. The aim of the chapter is to bring together some current ideas and concepts such as computational neuroscience, network theory, multi-omics profile, precision medicine, and person-centered psychiatry as a coherent system of theory and practice.

Temperament and prodromal symptoms prior to first manic/hypomanic episodes: results from a pilot study

BACKGROUND

Prodromal symptoms prior to first episode mania/hypomania have been reported. However, the relationship between temperament and manic/hypomanic prodromal symptoms has not been investigated. We hypothesized that subjects scoring higher on cyclothymic and irritable temperament scales show more manic/hypomanic prodromal symptoms.

METHOD

Euthymic patients diagnosed with bipolar-I or -II disorder within 8 years underwent retrospective assessments with the Temperament Evaluation of Memphis, Pisa, Paris and San Diego-autoquestionnaire (TEMPS-A) and the Bipolar Prodrome Symptom Scale-Retrospective (BPSS-R).

RESULTS

Among 39 subjects (36.1 ± 9.9 years, females = 59%, bipolar-I = 62%) 100% and 92.3% reported subthreshold mania (mean = 7.4 ± 2.9) or subthreshold depressive symptoms (mean = 2.4 ± 1.5), and 87.2% and 43.6% reported general psychopathology (mean = 3.2 ± 2.0) or subthreshold psychotic symptoms (mean = 0.7 ± 1.0) prior to their first hypo-/manic episode. Subjects with higher cyclothymic and irritable temperament scores showed more subthreshold symptoms prior to the first manic/hypomanic episode, mainly subthreshold hypo-/manic symptoms (cyclothymic temperament r = 0.430; p = 0.006; irritable temperament r = 0.330; p = 0.040), general psychopathology symptoms (cyclothymic temperament r = 0.316; p = 0.05; irritable temperament r = 0.349; p = 0.029) and subthreshold psychotic symptoms (cyclothymic temperament r = 0.413; p = 0.009). In regression analyses, cyclothymic temperament explained 16.1% and 12.5% of the variance of the BPSS-R total score (p = 0.045) and psychosis subscore (p = 0.029).

LIMITATIONS

Retrospective study, no control group, small sample size.

CONCLUSION

We present data, which indicate a relationship between cyclothymic and irritable temperament and prodromal symptoms prior to the first manic/hypomanic episode. These findings support the notion that assessing cyclothymic temperament to identify people at-risk of developing bipolar-I and -II disorder may help to increase the predictive validity of applied at-risk criteria.

Dimensional endophenotypes in bipolar disorder: affective dysregulation and psychosis proneness

BACKGROUND

The clinical phenotype of bipolar disorder (BPD) is heterogeneous and the genetic architecture of the disorder is complex and not well understood. Given these complications, it is possible that the identification of intermediate phenotypes ("endophenotypes") will be useful in elucidating the complex genetic mechanisms that result in the disorder. The examination of unaffected relatives is critical in determining whether a particular trait is genetically-relevant to BPD. However, few dimensional traits related to BPD have been assessed in unaffected relatives of patients.

METHODS

We assessed affective temperament and schizotypy in 55 discordant sibling pairs and 113 healthy controls (HCs) using the Temperament Evaluation of Memphis, Pisa, Paris, and San Diego, Auto-questionnaire version (TEMPS-A) to assess affective temperament and the Schizotypal Personality Questionnaire (SPQ) to assess schizotypy.

RESULTS

BPD patients scored significantly higher than HCs on all subscales of the SPQ and on all but one subscale (hyperthymic) of the TEMPS-A (all p<0.01). Siblings demonstrated scores that were significantly intermediate to patients and HCs on the anxious subscale of the TEMPS-A and on the interpersonal deficits and disorganized subscales of the SPQ.

LIMITATIONS

We did not investigate the BPD spectrum as most patients were diagnosed with BPD I (n=47). Most of the patients had experienced psychosis (n=42) and so we were unable to examine whether psychosis status impacted upon affective temperament or schizotypy in patients or their siblings.

CONCLUSION

These data suggest that schizotypy and affective temperament represent dimensional traits that are likely to underlie the genetic risk for BPD.