Hypomanic personality, social anhedonia and impulsive nonconformity: evidence for familial aggregation?

Schizophrenic and affective spectrum disorders aggregate in the families of patients afflicted with such disorders. Possible vulnerability markers for these disorders should therefore also run in families. The Chapmans and their coworkers developed the Hypomanic Personality Scale (HYP) to identify people at risk for affective disorders, and the scales Social Anhedonia (SA) and Impulsive Nonconformity (IMP) to assess schizotypy (Chapman et al., 1976, 1984; Eckblad & Chapman, 1986). The present family study investigated the familial resemblance of the HYP, SA, and IMP Scale using a maximum-likelihood approach. Index participants and their relatives (n = 717) completed a questionnaire packet that included the above-mentioned scales. Stepwise several models of familial correlations were specified and tested dealing with the influence of sex of parents and offspring and of interindividual cross-trait resemblance. For all three measures, there was evidence of familial resemblance. For SA and IMP, we found hints for possible assortative mating; additionally for HYP and IMP, an interindividual cross-trait resemblance (with correlations of 0.14 and 0.18, respectively) between family members emerged. The results support the validity of the HYP, SA, and IMP Scale. It is discussed whether HYP and IMP represent different aspects of a shared latent liability.