A twin study of the neuropsychological consequences of stimulant abuse

BACKGROUND: Previous studies document neuropsychological deficits associated with stimulant abuse, but findings are inconsistent. METHODS: We identified 50 twin pairs in which only 1 member had heavy stimulant abuse (cocaine and/or amphetamines) ending at least 1 year before the evaluation. The co-twin control research design controls for familial vulnerability and makes it easier to identify neuropsychological deficits that are consequences of stimulant abuse. Subjects were administered an extensive neuropsychological test battery organized into the following 5 functions: attention, executive functioning, motor skills, intelligence, and memory. RESULTS: Multivariate tests showed that abusers performed significantly worse than nonabusers on functions of attention and motor skills. Within each of these functions, univariate tests showed that abusers performed significantly worse on certain tests of motor skills and attention. In contrast, abusers performed significantly better on one test of attention measuring visual vigilance. Within the abuser group, higher levels of stimulant use were largely uncorrelated with neuropsychological test scores, although a few significant correlations indicated better functioning with more stimulant use. CONCLUSIONS: With ideal controls, this study demonstrates that deficits in attention and motor skills persist after 1 year of abstinence from stimulant use and raises hypotheses regarding relative strengths on a vigilance task among abusers.     

Family, twin, and adoption studies of bipolar disease

Bipolar disease features states of severe depression that usually fluctuate with at least one episode of intense elation or mania. It is a disorder that has been thought for some time to have a heritable component. The lifetime prevalence of bipolar disease in the general population is approximately 1%. In contrast, family studies have shown the approximate lifetime risk of a first-degree relative of a bipolar proband to be 5% to 10%. Moreover, studies of monozygotic twins show that their risk of contracting the disease is as much as 75 times greater than that for the general population. In addition, adoption studies have demonstrated that biological relatives of bipolar patients are substantially more likely to have the disorder than are adoptive relatives.     

Pilot study of spirituality and mental health in twins

OBJECTIVE: The goal of this study was to investigate associations between empirically defined dimensions of spirituality, personality variables, and psychiatric disorders in Vietnam era veterans. METHOD: One hundred pairs of male twins from the Vietnam Era Twin Registry were administered the self-report Spiritual Well-Being Scale and a pilot Index of Spiritual Involvement. Correlation analyses were supplemented with regression analyses that examined the relative influence of genetic and environmental factors on aspects of spirituality. RESULTS: Existential well-being was significantly associated with seven of 11 dimensions of personality and was significantly negatively associated with alcohol abuse or dependence and with two of three clusters of personality disorder symptoms. Associations between mental health variables and religious well-being or spiritual involvement were much more limited. CONCLUSIONS: Useful distinctions can be made between major dimensions of spirituality in studies of spirituality, religious coping, and mental health.     

Brain perfusion in autism varies with age

Our subjects consisted of 14 autistic individuals and 14 controls ranging in age from 3 to 37 years. A (99m)Tc HMPAO single photon emission computed tomogram (SPECT) was used to examine blood flow variations between autistic subjects, compared to an age- and gender-matched control group. We found significant hypoperfusion in the prefrontal areas of autistic individuals as compared to normals in every case (p < 0.01). As the age of the autistic individuals increased the hypoperfusion of verbal-associated areas in the left temporal lobe and frontal areas became more evident. The findings were significant at the p < 0.001 level. The changes in perfusion over time correlated with language development and acquisition as individuals matured. We conclude that autistic individuals have a deficiency in prefrontal areas associated with word identification and language formation skills. This subsequently prevents development of true verbal fluency and development in the temporal and frontal areas associated with speech and communication.     

The problem of obstetrical complications and schizophrenia

The use of the term "obstetrical complications" (OCs) and its variations to encompass diverse physiological mechanisms (e.g., genetic, ischemic, hemorrhagic, infectious) of disruption to fetal/neonatal brain development has engendered inconsistency, confusion, and controversy. The principal reason is that the term OCs belies the absence of a fully adequate conceptual framework for characterizing neurodevelopmental risk. We propose that neurodevelopmental risk factors for schizophrenia can be assessed more clearly if broad OC scales are replaced by measures representing more homogeneous pathways of disturbed brain development. Using a new OC classification, we found that disordered growth related to hypoxic-ischemic compromise to early brain development may confer an elevated risk of schizophrenia and other adult-onset psychoses, particularly in the presence of familial risk. Abnormal fetal and neonatal brain growth and development in schizophrenia and OCs may also, at least in part, result from genetic factors and could help explain the relation between seemingly inconsistent OCs identified in prior research.     

Response to alcohol in daughters of alcoholics: a pilot study and a comparison with sons of alcoholics

Drinking, but not alcohol-dependent, 18-29-year-old daughters of alcoholics (n = 38) from the Collaborative Study on the Genetics of Alcoholism were compared to 75 family-history-positive (FHP) men from the same families, and 68 family-history-negative (FHN) male controls. Subjects received 0.75 ml/kg of ethanol (for women), 0.9 ml/kg of ethanol (for men), and placebo, each of which was consumed over 8 min on different occasions. The breath-alcohol concentrations (BrAC) and reactions to alcohol [using the Subjective High Assessment Scale (SHAS) and body sway measures] were evaluated over 210 min. The results indicate that, despite slightly higher BrAC values for the FHP men, on the SHAS the FHP women and the FHP men demonstrated significantly lower scores than the FHN male controls, although the values for FHP men and women did not differ. On body sway, the FHP men showed evidence of less alcohol-related increases than FHN men, and there was a trend in the same direction for FHP women, but only early in the session (e.g. at 60 min). Pilot data for 11 FHN women revealed higher scores for both SHAS and body sway at 60 min, compared to FHP women, but, perhaps reflecting the small number of subjects, the family history differences were not significant. Overall, the results in FHP women resemble those for FHP men, and suggest that a low level of response to alcohol might also be a characteristic of daughters of alcoholics.     

Empirical determination of thresholds for case identification: Validation of the Personality Diagnostic Questionnaire-Revised

The Personality Diagnostic Questionnaire-Revised (PDQ-R) was sent to first-degree relatives of major psychotic patients for identification of DSM-III-R personality disorders (PDs). Responses to the PDQ-R were interpreted both literally and empirically, and compared with the Structured Interview for DSM-III PDs (SIDP) as the standard. For literal interpretation, symptoms reported were counted directly for case identification using fixed DSM-III-R thresholds. The empirical approach adjusted the threshold for case identification to maximize concordance with the SIDP. Comparison of the two methods showed that using empirically determined thresholds in some scales gives better concordance with the SIDP. For the dependent and histrionic PD scales, the improvements were statistically significant. The area under the receiver operating characteristic (ROC) curve was computed for each PDQ-R scale to summarize its discriminatory capability across all thresholds. Areas under the ROC curve indicated that the schizoid, schizotypal, borderline, dependent, passive-aggressive, and histrionic PD scales in the PDQ-R have better discriminatory qualities than other PDQ-R scales.     

Benefits for employees with children with ADHD: findings from the Collaborative Employee Benefit Study

Parents of most children with attention-deficit hyperactivity disorder (ADHD) are employed. Employers have interest in decreasing employee absenteeism and improving workplace productivity, partly through employee benefits. The authors interviewed employers to (1) determine how they view the needs of employees with children with ADHD and (2) identify benefits that might help employees with children with ADHD. The authors carried out a systematic interview study of mainly family-friendly, large employers in four U.S. urban markets (Boston, Cleveland, Miami, Seattle). Multidisciplinary interview teams used a protocol to gather basic company information, benefit philosophy, current insurance and other employee benefits, and knowledge of ADHD and its impacts on employees. Initially, the interview team and then the larger project team reviewed all protocols for common themes. The authors interviewed staff of 41 employers (human resource managers, work/life program directors, benefits directors). Only 15 of 41 interviewees knew about ADHD, its prevalence, or its effects on parents. They had little knowledge of how differences in managed behavioral health may affect families' access to diagnostic and treatment services for ADHD, although most had experience with primary care management of depression among employees. Employers offer a variety of other benefits, including work/life and employee assistance programs, occasionally providing employees help with caring for a child with a mental health condition, on-site parent training programs, or assistance with child care. Other potentially useful employee benefits include flexible work and leave policies and information and referral services that can link parents with community programs. Although employers have limited awareness of ADHD and its potential effect on employees' work, this study identified opportunities to improve both health insurance and other benefits for employees with children with ADHD.