Symptom Dimensions in OCD: Item-Level Factor Analysis and Heritability Estimates

To reduce the phenotypic heterogeneity of obsessive-compulsive disorder (OCD) for genetic, clinical and translational studies, numerous factor analyses of the Yale-Brown Obsessive Compulsive Scale checklist (YBOCS-CL) have been conducted. Results of these analyses have been inconsistent, likely as a consequence of small sample sizes and variable methodologies. Furthermore, data concerning the heritability of the factors are limited. Item and category-level factor analyses of YBOCS-CL items from 1224 OCD subjects were followed by heritability analyses in 52 OCD-affected multigenerational families. Item-level analyses indicated that a five factor model: (1) taboo, (2) contamination/cleaning, (3) doubts, (4) superstitions/rituals, and (5) symmetry/hoarding provided the best fit, followed by a one-factor solution. All 5 factors as well as the one-factor solution were found to be heritable. Bivariate analyses indicated that the taboo and doubts factor, and the contamination and symmetry/hoarding factor share genetic influences. Contamination and symmetry/hoarding show shared genetic variance with symptom severity. Nearly all factors showed shared environmental variance with each other and with symptom severity. These results support the utility of both OCD diagnosis and symptom dimensions in genetic research and clinical contexts. Both shared and unique genetic influences underlie susceptibility to OCD and its symptom dimensions.Obsessive Compulsive FoundationTourette Syndrome AssociationAnxiety Disorders Association of AmericaAmerican Academy of Child and Adolescent Psychiatr

Psychiatric Disorders

This chapter summarizes the most significant gender influences on mental health in terms of illness incidence and prevalence, clinical presentation, course, and response to treatment. Several mental disorders including major depression, bipolar disorder, anxiety disorders, schizophrenia, and eating disorders are considered in different sections. Depression is twice more frequent in women than in men. Moreover, men and women show differences regarding presentation, course, treatment response, and outcome. Women affected by depression show higher recurrence and atypical features; they have generally an earlier onset, more severe, longer, and recurrent depressive episodes, and a lower quality of life than men do. Women are also more likely to have a comorbid anxiety, eating or somatoform disorder, and more frequently than men, they attempt suicide (although lethal suicide is more probable to happen in men). Psychopharmacological treatment of depression also might present significant gender dissimilarities; still, there is no clear consensus on whether there are gender-related differences in antidepressant efficacy. There is a significant gender difference in terms of lifetime prevalence of bipolar disorder type II, with more affected women, while both genders show a similar prevalence of bipolar disorder type I. Women usually have an older age of onset and they typically manifest a depressive polarity at the onset and a predominance of depression phases during lifetime. Women are also more likely to undergo mixed and seasonal episodes and have an increased risk of developing rapid cycling mood disturbances. Bipolar disorder in men is characterized by manic onset, recurrence of manic phases, and by lower treatment adherence. Comorbidity of psychiatric (eating and anxiety disorders) and medical (thyroid disease, migraine, obesity) conditions are more common in women, while substance use disorder is more common in men. There is no evidence that women and men suffering from bipolar disorder differ significantly in treatment response to mood stabilizers. Schizophrenia also has significant gender differences: affected males, normally younger at the onset than females, present more severe negative symptoms, worse cognitive impairment, more frequent hospitalizations, and are more likely to commit acts of severe violence. In detail, incidence rate of early onset is higher in males than females, while at older onset women predominate. Until the mid-30s, rates are estimated to be approximately 1.5\u20132 times greater in males than females. Later, rates decrease for both sexes, with a narrowing sex ratio, until the mid-40s when there is a minor secondary peak for women. Male patients are likely to have more cognitive impairment and poorer premorbid functioning, more negative symptoms, and more severe deterioration over time. Female patients experienced more severe positive symptoms (hallucinations and persecutory delusions) and commit a greater number of suicide attempts. Women also show a considerably less severe course of the illness: they show a better social functioning and have fewer hospitalizations with shorter inpatient stays. Gender differences have also been well recognized in the response to antipsychotic treatment, with women being better responders than men are. Eating disorders in the past were considered as almost exclusively female disorders (F:M = 20:1), but that is changing rapidly. One million men have been shown to suffer from eating disorders in the USA. Males accounted for roughly 10.0\u201325.0% of eating disorder patients, with the number of men struggling from bulimia nervosa being more than those who struggle with anorexia. Research and knowledge on the topic are expanding rapidly, and recent literature elucidates gender-specific issues in terms of age of onset, weight history and compensatory exercise behavior, frequency of abuse record, and substance use rates. A later age of onset, premorbid obesity, and over-exercise are more likely in men. Around 30% of subjects suffering from an eating disorder were victims of sexual abuse (1:3 in women vs. 1:7 in men) and a substance use disorder is generally more frequent in subjects with eating disorder (particularly the use of steroids and growth hormones in affected men) in comparison to the general population