Generalized anxiety disorder: is there any specific symptom?

Genetic examination of the Mood Disorder Questionnaire and its relationship with bipolar disorder

The Mood Disorder Questionnaire (MDQ) is a common screening tool for bipolar disorder that assesses manic symptoms. Its utility for genetic studies of mania or bipolar traits has not been fully examined. We psychometrically compared the MDQ to self-reported bipolar disorder in participants from the United Kingdom National Institute of Health and Care Research Mental Health BioResource. We conducted genome-wide association studies of manic symptom quantitative traits and symptom subgroups, derived from the MDQ items (N = 11,568-19,859). We calculated genetic correlations with bipolar disorder and other psychiatric and behavioral traits. The MDQ screener showed low positive predictive value (0.29) for self-reported bipolar disorder. Neither concurrent nor lifetime manic symptoms were genetically correlated with bipolar disorder. Lifetime manic symptoms had a highest genetic correlation (rg  = 1.0) with posttraumatic stress disorder although this was not confirmed by within-cohort phenotypic correlations (rp  = 0.41). Other significant genetic correlations included attention deficit hyperactivity disorder (rg  = 0.69), insomnia (rg  = 0.55), and major depressive disorder (rg  = 0.42). Our study adds to existing literature questioning the MDQ's validity and suggests it may capture symptoms of general distress or psychopathology, rather than hypomania/mania specifically, in at-risk populations.

From psychological to physical health: Exploring temporal precedence throughout emotion regulation therapy

OBJECTIVE

Generalized anxiety disorder (GAD) is characterized, in part, by physical symptoms such as muscle tension and gastrointestinal (GI) distress. To date, little research has examined how changes in psychological symptoms associated with GAD may impact physical symptoms. This study investigated if reductions in worry, anxiety, and depression precede changes in muscle tension and GI distress throughout psychotherapy.

METHODS

Participants with GAD (N = 85) completed 20 weeks of emotion regulation therapy (ERT) in addition to assessments pre, mid, and post treatment. They completed a physical symptom questionnaire, evaluating muscle tension and GI distress. Participants also completed psychological symptoms questionnaires, including the State Trait Anxiety Inventory (STAI-7), Penn State Worry Questionnaire (PSWQ), and Beck Depression Inventory (BDI-II). Control participants (N = 44) completed these measures at baseline.

RESULTS

Participants with GAD had significantly greater muscle tension (p <  .001) and GI distress (p <  .001) compared to control participants without GAD. Reductions in worry, depression, and trait anxiety did not precede changes in muscle tension (range of effect size (r): .05-.12). Reductions in both depression (p = 0.04) and trait anxiety (p < 0.01) preceded reductions in GI distress. Reductions in worry did not precede reductions in GI distress (p = 0.25).

CONCLUSION

These data provide preliminary evidence for the temporal effect of reductions in psychological symptoms on reductions in GI distress in GAD, highlighting the potential of psychotherapy to improve physical outcomes.

The lifetime prevalence and impact of generalized anxiety disorders in an epidemiologic Italian National Survey carried out by clinicians by means of semi-structured interviews

BACKGROUND

Generalized anxiety disorder (GAD) is one of the most reported diagnoses in psychiatry, but there is some discrepancy between the cases identified in community studies and those identified in tertiary care. This study set out to evaluate whether the use of clinicians as interviewers may provide estimates in a community survey close to those observed in primary or specialized care.

METHODS

This is a community survey on a randomly selected sample of 2338 adult subjects. The Advanced Neuropsychiatric Tools and Assessment Schedule (ANTAS) was administered by clinicians, providing lifetime diagnosis based on the DSM-IV-TR. Health-related quality of life (HR-QoL) was measured with the Short-Form Health Survey (SF-12).

RESULTS

Overall, 55 (2.3%) subjects met the criteria for GAD, with greater prevalence in women (3.6%) than in men (0.9%): OR = 4.02; 95%CI: 1.96-8.26. Up to 40% of those with GAD had at least another diagnosis of mood, anxiety, or eating disorders. The mean score of SF-12 in people with GAD was 32.33 ± 6.8, with a higher attributable burden than in other conditions except for major depressive disorder.

CONCLUSIONS

We found a relatively lower lifetime prevalence of GAD than in community surveys based on lay interviewers and a structured interview. The identified cases of GAD showed a strong impact on the quality of life regardless of co-morbidity and high risk in women, suggesting a profile similar to the one identified from studies in primary and specialized care.

Risk Factors, Clinical Presentations, and Functional Impairments for Generalized Anxiety Disorder in Military Personnel and the General Population in Canada

OBJECTIVE

This study sought to examine differences in sociodemographic risk factors, comorbid mental conditions, clinical presentations, and functional impairments associated with past-year generalized anxiety disorder (GAD) between Canadian Armed Forces (CAF) Regular Force personnel and the Canadian general population (CGP).

METHOD

Data were from 2 nationally representative surveys collected by Statistics Canada: 1) the Canadian Community Health Survey on Mental Health, collected in 2012 ( N = 25,113; response rate = 68.9%); and 2) the Canadian Forces Mental Health Survey, collected in 2013 ( N = 8,161; response rate = 79.8%).

RESULTS

The prevalence of lifetime and past-year GAD was significantly higher in the CAF (12.1% and 4.7%) than in the CGP (9.5% and 3.0%). Comorbid mental disorders were strongly associated with GAD in both populations. Although the content area of worry and the GAD symptoms endorsed were similar, CAF personnel were significantly more likely to endorse specific types of worries (i.e., success at school/work, social life, mental health, being away from home or loved ones, and war or revolution) and specific symptoms of GAD (i.e., restless, keyed up, or on edge and more irritable than usual) than civilians, after adjusting for sociodemographic covariates and comorbid mental disorders. CAF personnel with past-year GAD reported significantly higher functional impairment at home than civilians with past-year GAD.

CONCLUSION

GAD is a substantial public health concern associated with significant impairment and disability in both military and civilian populations. GAD in military and civilian populations shows similarities and differences: Key similarities include its extensive comorbidity and significant functional impairment, whereas key differences include the focus of worries and symptom profile.

The impact of the intensity of single symptoms on the diagnosis and prevalence of major depression

OBJECTIVE

Diagnoses are based on algorithms which count symptoms. The question is whether all or only sufficiently severe complaints of patients should qualify as diagnostic criteria and how prevalence rates of mental disorders change when all or only moderate or severe complaints are counted as symptoms in diagnostic algorithms.

METHOD

One hundred thirty-nine general practice patients were diagnosed as suffering from major depression according to DSM-IV on the basis of the standardized clinical International Neuropsychiatric Diagnostic Interview (MINI). They additionally filled in the self-rating SCL-90, which allows patients to rate the intensity of each symptom on a five-point Likert scale. The diagnostic algorithm for major depression was modeled on the basis of the SCL-90 self-rating. MINI-diagnoses were compared with SCL-diagnoses when symptoms with different intensity were taken into account.

RESULTS

The prevalence of "SCL-90-major depression" is 77.2% if all symptoms are counted, and 38.7% if only at least moderately severe symptoms, or 5.0% if only extremely severe symptoms are included in the diagnostic algorithm. Sensitivity rates vary from 10.8%, if only extremely severe symptoms are counted, to 94.2% if all complaints were included. Specificity rates vary from 37.4% for all complaints and 100% for extremely severe items. Accuracy is best when "a little bit" of complaint is omitted (78.1%) and lowest if only extremely severe symptoms are counted (58.9%).

CONCLUSION

The data demonstrate the importance of the severity of single symptoms for the diagnosis of mental disorders. Symptom definition, recognition, and evaluation must find greater attention in research, clinical practice, and training of physicians.