Therapeutic and genetic prospects of an atypical affective disorder

The utility of bipolar type II affective disorder subgrouping is discussed. There is low diagnostic agreement among clinicians for this putative condition. However, the clustering of cases in families and the poor response to standard treatments suggest that it is a distinct subgroup. The clinical features of the depressive phase of this condition including chronicity, intermittency, hyperphagia, hypersomnia, and reactivity relate it to the constructs of "hysteroid dysphoria," atypical depression, and seasonal affective disorder. Its association to several abnormal motivated behaviors such as alcoholism and eating disorders allows the speculation that a distinct morbid mechanism involving serotonin may underlie it and that new serotonin reuptake blocking drugs may be useful in treating it. Finally, the genetic identity of this subgroup in all likelihood will be established or rejected by genetic linkage studies utilizing the restriction fragment length polymorphism map of the genome.

Male primary alcoholics with and without family histories of affective disorder

The relationship between the clinical course and a family history of affective disorder among 377 carefully diagnosed male primary alcoholics admitted to the Alcohol Treatment Program (ATP) at the San Diego Veterans Administration Medical Center is evaluated. Data were gathered from interviews with patients and two resource persons at intake and from patients and one resource person interview obtained on 361 (95%) of the men 12 months after discharge. The 37 primary alcoholic men (10%) who had a first-degree family member with affective disorder were themselves more likely to have had secondary depressions and to have experienced more alcohol-related problems at 1-year follow-up than the 90% of primary alcoholic men without such family histories. However, many clinical characteristics associated with a family history of affective disorder were similar to those observed in men with family histories of alcoholism. This indicates the possibility that the presence of a family history of illness in general may be as important as the specific diagnoses of affective disorder or alcoholism in the close family member.

Twin concordance for DSM-III schizophrenia. Scrutinizing the validity of the definition

DSM-III diagnoses were applied to 26 monozygotic (MZ) and 34 dizygotic (DZ) probands and their co-twins from the Maudsley Hospital (1948 to 1965) schizophrenic series of Gottesman and Shields. DSM-III criteria for schizophrenia were found to be highly reliable and valid, and to have a broad heritability of 0.85, which is comparable with the Research Diagnostic Criteria and Feighner criteria from which they were derived. When the full range of DSM-III diagnoses were considered, both affective disorder and schizophrenia were found in genetically identical individuals. The effect of DSM-III nosology on the twin series was also explored by adding other diagnoses to that of schizophrenia and observing the effect on the MZ/DZ concordance ratio. The addition of affective disorder with mood-incongruent delusions to the schizophrenia spectrum produced the largest increase in the ratio and, by implication, a "more genetic" combination than schizophrenia alone. The maximum MZ/DZ concordance ratio (7.68) was produced by schizophrenia, plus affective disorder with mood-incongruent delusions, plus schizotypal personality disorder, plus atypical psychosis. The effect of adding paranoid disorder (paranoia) and all other affective categories was a reduction in the ratio.

Panic disorder: evidence for genetic vulnerability

Many studies have suggested that a genetic predisposition to the development of panic disorder exists. These studies are examined and their limitations discussed. It is suggested that only by the analysis of comprehensive family and twin data, coupled with other measures such as the search for possible single gene association or linkage and study of the children of panic disorder patients, will the mechanism for the 'familiarity' noted in panic disorder patients be elucidated. Delineation of the mode of transmission of panic disorder may allow preventative intervention with those at risk before they develop panic.

Psychiatric morbidity among relatives of different subgroups of neurotic depression

The morbidity risk for affective disorders was calculated among the relatives of subgroups of reactive-neurotic depressive patients. The patients were divided into reactive and neurotic depressives. The parents of the neurotic subgroup had a significantly lower morbidity risk of affective disorders in comparison with the parents of the reactive subgroup. The role of genetic and environmental factors in the etiology of reactive-neurotic depression was discussed.

Close linkage of c-Harvey-ras-1 and the insulin gene to affective disorder is ruled out in three North American pedigrees

Affective disorder (AD) is one of the major forms of functional psychoses. Although the mode of transmission is uncertain, family, twin and adoption studies strongly suggest a genetic involvement. Because a basic biochemical abnormality is not known, direct analysis of the disease using a probe for the defective gene is not possible. However, a specific locus can be tested for its relevance to the aetiology of AD by genetic linkage, using restriction fragment length polymorphisms (RFLPs). Using probes for the c-Ha-ras-1 oncogene and the insulin gene, Gerhard et al. and Egeland et al. found convincing evidence for close linkage between these markers and a locus for AD in a large Old Order Amish pedigree. In an attempt to confirm this finding, we examined three bipolar pedigrees outside the Amish population. Our results indicate the absence of linkage from 0 to 15% recombination frequency between AD and the insulin gene-HRAS1 region in these pedigrees.

Sex differences in affective disorder: genetic transmission

Epidemiological studies have consistently found women to be at greater risk than men for affective disorders. This sex effect may help clarify genetic transmission and heterogeneity. Data from eight family studies of unipolar and eight family studies of bipolar probands were used to calculate family resemblance sex ratios. These observed sex ratios were then compared to sex ratios predicted by X-linked and nonfamilial effects models. Maximum likelihood estimation of competing models revealed that X linkage was not a good fit to the unipolar data. The bipolar studies were not consistent with either the X-linked or the nonfamilial effects model.

Sampling problems in twin research

Sampling problems related to twin problems may be of at least three kinds: small samples, self-selection and unrepresentative ascertainment. The article mostly discusses the third type of sample problem. Data from a nationwide Norwegian twin study show that the results of twin studies will be quite different depending upon the ascertainment procedure. According to both the ICD-9 as well as the DSM-III classification system, only samples ascertained from mental hospitals treating severe cases are able to demonstrate hereditary factors of any strength.

Platelet 3H-imipramine binding and familial transmission of affective disorders

We studied platelet 3H-imipramine binding and family history of affective illness in 26 patients with bipolar affective disorder and 24 patients with unipolar affective disorder. The density of platelet 3H-imipramine binding sites (Bmax) was significantly lower in bipolar patients with family history of affective illness than in healthy controls; however, there was a considerable overlap in Bmax values between the familial cases and the normal controls. A similar trend was observed in familial cases of unipolar disorder but the differences fell short of statistical significance. The nonfamilial cases of affective disorder did not differ from the healthy controls. The possible role of reduced platelet 3H-imipramine binding as a genetic vulnerability 'marker' in affective disorder was discussed.

Research design considerations for linkage studies of affective disorders using recombinant DNA markers

A genetic linkage study is one approach to resolving the etiology of a major psychiatric disorder either by testing involvement of a specific candidate gene or by demonstrating the existence of some unidentified gene in a specific place on the genome. Because of the complexities of psychiatric disorders, a successful linkage study must be built upon accurate and reliable diagnosis, families with multiple affected members, highly informative genetic markers, and powerful multipoint linkage methods. Over the last decade, great advances have been made in all these areas. Linkage studies are not only appropriate for affective and other major psychiatric disorders but are already beginning to yield promising results.

Sustained attention in children at risk for schizophrenia: findings with two visual continuous performance tests in a new sample

In partial replication of an earlier study, 35 children at high risk for schizophrenia, 25 children at high risk for affective disorder, and 53 normal control children from a new sample of 7- to 12-year-old subjects were tested with two new visual continuous performance tests. Response levels and intrasubject variability were analyzed separately. Multivariate analyses on factor scores derived from response levels indicate that "groups" is a significant predictor for a factor reflecting discriminability (or sensitivity) for the more difficult of these tests but not for the less difficult one, and that high risk for schizophrenia is associated with lower performance. Factor scores and multiple regression analyses were used to dichotomize subjects as to whether or not they are low performance outliers. A significantly larger proportion of subjects from the high risk for schizophrenia group than from the control groups were low performance outliers. Among subjects that developed psychopathology in adolescence, subjects at high risk for schizophrenia were more likely to have contributed low performance outliers early during childhood.

Affective illness in substance abusers

The evaluation and treatment of substance abusers are complicated tasks, requiring a multifaceted approach. In addition to the patient's substance abuse problems, a substantial minority appear to be suffering from concurrent, nondrug-related psychiatric disorders. The early identification of such individuals allows for the development of specific treatment strategies that address both the substance abuse and the associated nondrug psychopathology. On the other hand, attention to nondrug psychopathology should not preclude our simultaneously addressing the patient's substance abuse problem. Thus, manic depressive patients who are also alcoholic may need a treatment program that includes alcoholism counseling. Alcoholics Anonymous, and chronic administration of disulfiram in addition to lithium carbonate and a supportive psychotherapeutic relationship. As in other areas of medicine, attention to the "whole patient" is the sine qua non of good treatment.

Descriptive, biological, and theoretical aspects of borderline personality disorder

Although the diagnosis of borderline personality disorder has reasonable interrater and test-retest reliability, its discriminative validity is poor. The authors review studies indicating that the patient group subsumed by the borderline category actually includes those with various affective, organic, and schizotypal disorders. They speculate that borderline personality disorder represents a broad range of affective disorders resulting in part from childhood object loss, which may impair the reinforcement mechanisms necessary for the development of competent object relations.

Event-related potentials in children at risk for schizophrenia during two versions of the continuous performance test

Event-related potentials (ERPs) were recorded from children of schizophrenic parents, children of parents with affective disorders, and children of parents without a history of psychiatric illness. ERPs were elicited during two versions of the continuous performance test (CPT), which differed in their level of processing complexity. The data were recorded from electrodes located at midline frontal, central, parietal, and occipital scalp sites. Diagnostic assessments of the parents were performed using the Schedule for Affective Disorders and Schizophrenia-Lifetime Version and Research Diagnostic Criteria. Clinical assessments of the children were made with a modified version of the Global Assessment Scale. ERP amplitudes for six electrophysiological events were compared among groups for target and nontarget stimuli using analyses of variance of both factor score and baseline to peak measures. There was one isolated between-group finding: frontal negative slow wave recorded at FZ was of greater magnitude in the high risk (HR) than in either the psychiatric (PC) or normal control (NC) groups. Since only a small percentage of children at risk will eventually develop schizophrenia, ERP amplitude deviance and frequency distribution analyses were also performed and compared among groups. ERP component amplitudes did not distinguish the groups when each component was considered separately. Deviance analyses, using a combination of the amplitudes of the six ERP components, also did not provide evidence of a deviant subgroup within any of the three groups. There appeared to be no relationship between ERP component amplitudes and behavioral adjustment in adolescence. Some evidence of a relationship between deviant attentional functioning and ERP component amplitude was found, but the pattern of findings within the attentionally deviant HR subgroup was opposite to that found for the HR group as a whole and more consistent with the pattern found for the NC group.

Genetic factors in moderately severe and mild affective disorders

The aim of this study was to investigate the contribution of hereditary factors in the development of affective and depressive adjustment disorders. I interviewed 151 index twins with moderately severe and mild affective illness, as well as their co-twins. The analysis of concordance rates indicates that hereditary factors may be important in the development of bipolar disorder and in major depression, except in non-psychotic, hysterical individuals. Furthermore, hereditary factors may not play any role in dysthymic disorder and depressive adjustment disorder. These findings are tentative and should be viewed against the methodologic limitations of this study, which include small sample size of the subgroups and the use of the Present State Examination as the basis for the DSM-III diagnoses.