Comorbidity as a fundamental feature of generalized anxiety disorders: results from the National Comorbidity Study (NCS)

Abstract

Generalized anxiety disorder (GAD) is a relatively commun mental disorder in the general population, afflicting approximately 3% of community residents during their lifetime. It is not a benign condition, since significantly increased disability and dysfunction are found in GAD subjects compared to non‐GAD subjects. For decades GAD has frequently been observed in the context of other mental and substance abuse disorders. Initially the weight of clinical opinion indicated that GAD was a residual disease which should only be diagnosed when other mental disorders are not present. More recently there has been a growing recognition that comorbidity is a fundamental characteristic of the course and nature of GAD. In a series of secondary analyses conducted in subjects in the National Comorbidity Study database, we found that 8 out of 10 subjects with lifetime GAD also had a comorbid mood disorder during their lifetime. We found unipolar disorders to be four times more common in GAD than bipolar disorders (67% vs. 17%), providing indirect support for the previously reported observation that GAD and major depression may share a common genetic diathesis. In addition, our analyses support the conclusion that when comorbid mood disorders are present in GAD, a significant increase in associated disability and dysfunction is also found. Thus this comorbid relationship has important implications for clinical course and outcome.

Human and economic burden of generalized anxiety disorder

“…A study of past-year DSM-III-R disorders showed that 27% of respondents with comorbid GAD/MDD (n 5 99) reported the highest level of social impairment on a measure of social functioning compared with 8.4% of respondents with neither disorder (n 5 5217); the corresponding proportion was 24% and 23% for respondents with pure GAD (n 5 92) and pure MDD (n 5 489), respectively . A similar pattern was observed for respondents with lifetime GAD when comorbidity with other affective disorders was examined [Judd et al, 1998]. …”

Risco de suicídio e comorbidades psiquiátricas no transtorno de ansiedade generalizada

“…De acordo com o DSM-5, para ser diagnosticada, deve durar pelo menos seis meses e ser acompanhada de pelo menos três dos seguintes sintomas: inquietação, irritabilidade, fatigabilidade, perturbação do sono, tensão muscular e/ ou dificuldade de concentração 2 . O National Comorbidity Survey Replication (NCS-R), principal estudo epidemiológico norte-americano, que avaliou 9.282 pessoas da comunidade, encontrou prevalência de 5,7% de TAG durante a vida 3 , enquanto estudos europeus chegaram a relatar prevalência de até 6,9% 4 . O Estudo Epidemiológico dos Transtornos Mentais São Paulo Megacity (2009), que avaliou 5.037 indivíduos da região metropolitana de São Paulo, revelou que 19,9% apresentam algum transtorno de ansiedade e 2,3% possuem TAG 5 ; essas proporções, segundo esse mesmo estudo, seriam semelhantes às encontradas em outros grandes centros urbanos brasileiros.…”

Comorbidity of Anxiety and Affective Disorders as Neuropsychiatric and Evolutionary Problem (A New Concept)

“…The principal data on comorbidity of affective and anxiety disorders are listed in the table 1. This table has been created based on literature findings relevant to prevalence of depression and anxiety and their concomitant existence in general population Kessler, 1999;Kessler et al, 1994Kessler et al, , 1995Kessler et al, , 1996Kessler et al, , 1999Judd et al, 1998 As can be seen from table 1 there are certain discrepancies in variables "Comorbidity 1" and "Comorbidity 2": the "Comorbidity 1" is 2 -5,5 fold lower, then "Comorbidity 2" level. In other words, the primary and main diagnosis of MDD has caused lower level of comorbidity with any AD, while the primary diagnosis of AD has lead to higher level of comorbidity with MDD, and the last category seems to be more consistently present in comorbid pairs, than AD.…”