Brian J. Cox

Psychometric properties of the 42-item and 21-item versions of the Depression Anxiety Stress Scales in clinical groups and a community sample.

The factor structure, reliability, and validity of the Depression Anxiety Stress Scales (DASS; S. H. Lovibond & P. F. Lovibond, 1995) and the 21-item short form of these measures (DASS-21) were examined in nonclinical volunteers (n = 49) and patients with Diagnostic and Statistical Manual of Mental Disorders (4th ed.; American Psychiatric Association, 1994) diagnoses of panic disorder (n = 67), obsessive-compulsive disorder (n = 54), social phobia (n = 74), specific phobia (n = 17), and major depressive disorder (n = 46). This study replicates previous findings indicating that the DASS distinguishes well between features of depression, physical arousal, and psychological tension and agitation and extends these observations to the DASS-21. In addition, the internal consistency and concurrent validity of the DASS and DASS-21 were in the acceptable to excellent ranges. Mean scores for the various groups were similar to those in previous research, and in the expected direction. The implications of these findings are discussed.

Robust Dimensions of Anxiety Sensitivity: Development and Initial Validation of the Anxiety Sensitivity Index-3.

Accumulating evidence suggests that anxiety sensitivity (fear of arousal-related sensations) plays an important role in many clinical conditions, particularly anxiety disorders. Research has increasingly focused on how the basic dimensions of anxiety sensitivity are related to various forms of psychopathology. Such work has been hampered because the original measure--the Anxiety Sensitivity Index (ASI)--was not designed to be multidimensional. Subsequently developed multidimensional measures have unstable factor structures or measure only a subset of the most widely replicated factors. Therefore, the authors developed, via factor analysis of responses from U.S. and Canadian nonclinical participants (n=2,361), an 18-item measure, the ASI-3, which assesses the 3 factors best replicated in previous research: Physical, Cognitive, and Social Concerns. Factorial validity of the ASI-3 was supported by confirmatory factor analyses of 6 replication samples, including nonclinical samples from the United States and Canada, France, Mexico, the Netherlands, and Spain (n=4,494) and a clinical sample from the United States and Canada (n=390). The ASI-3 displayed generally good performance on other indices of reliability and validity, along with evidence of improved psychometric properties over the original ASI.

Mood and anxiety disorders associated with chronic pain: an examination in a nationally representative sample

&NA; Chronic pain and psychiatric disorders frequently co‐occur. However, estimates of the magnitude of these associations have been biased by the use of select clinical samples. The present study utilized the National Comorbidity Survey [Arch. Gen. Psychiatry 51 (1994) 8–19] Part II data set to investigate the associations between a chronic pain condition (i.e. arthritis) and common mood and anxiety disorders in a sample representative of the general US civilian population. Participants (N=5877) completed the Composite International Diagnostic Interview [World Health Organization (1990)], a structured interview for trained non‐clinician interviewers based on the revised third edition of the Diagnostic and Statistical Manual of Mental Disorders [American Psychiatric Association (1987)], and provided self‐reports of pain and disability associated with a variety of medical conditions. Significant positive associations were found between chronic pain and individual 12‐month mood and anxiety disorders [odds ratios (OR) ranged from 1.92 to 4.27]. The strongest associations were observed with panic disorder (OR=4.27) and post‐traumatic stress disorder (OR=3.69). The presence of one psychiatric disorder was not significantly associated with pain‐related disability, but the presence of multiple psychiatric disorders was significantly associated with increased disability. The findings of the present study raise the possibility that improved efforts regarding the detection and treatment of anxiety disorders may be required in pain treatment settings.

Depression and anxiety associated with three pain conditions: results from a nationally representative sample

&NA; Investigations of the relationship between pain conditions and psychopathology have largely focused on depression and have been limited by the use of non‐representative samples (e.g. clinical samples). The present study utilized data from the Midlife Development in the United States Survey (MIDUS) to investigate associations between three pain conditions and three common psychiatric disorders in a large sample (N=3032) representative of adults aged 25–74 in the United States population. MIDUS participants provided reports regarding medical conditions experienced over the past year including arthritis, migraine, and back pain. Participants also completed several diagnostic‐specific measures from the Composite International Diagnostic Interview‐Short Form [Int. J. Methods Psychiatr. Res. 7 (1998) 171], which was based on the revised third edition of the Diagnostic and Statistical Manual of Mental Disorders [American Psychiatric Association 1987]. The diagnoses included were depression, panic attacks, and generalized anxiety disorder. Logistic regression analyses revealed significant positive associations between each pain condition and the psychiatric disorders (Odds Ratios ranged from 1.48 to 3.86). The majority of these associations remained statistically significant after adjusting for demographic variables, the other pain conditions, and other medical conditions. Given the emphasis on depression in the pain literature, it was noteworthy that the associations between the pain conditions and the anxiety disorders were generally larger than those between the pain conditions and depression. These findings add to a growing body of evidence indicating that anxiety disorders warrant further attention in relation to pain. The clinical and research implications of these findings are discussed.

An Expanded Anxiety Sensitivity Index: Evidence for a Hierarchic Structure in a Clinical Sample

Anxiety sensitivity (AS) is the fear of anxiety-related sensations. According to Reisss (e.g., Reiss, 1991) expectancy theory, AS amplifies fear and anxiety reactions, and plays an important role in the etiology and maintenance of anxiety disorders, particularly panic disorder. Recent evidence suggests that AS has a hierarchical structure, consisting of multiple lower order factors, loading on a single higher order factor. If each factor corresponds to a discrete mechanism (Cattell, 1978), then the results suggest that AS arises from a hierarchic arrangement of mechanisms. A problem with previous studies is that they were based on the 16-item Anxiety Sensitivity Index, which may not contain enough items to reveal the type and number of lower order factors. Also, some of the original ASI items are too general to assess specific, lower order factors. Accordingly, we developed an expanded measure of AS--the ASI-R--which consists of 36 items with subscales assessing each of the major domains of AS suggested by previous studies. The ASI-R was completed by 155 psychiatric outpatients. Factor analyses indicated a four-factor hierarchical solution, consisting of four lower order factors, loading on a single higher factor. The lower order factors were: (1) fear of respiratory symptoms, (2) fear of publicly observable anxiety reactions, (3) fear of cardiovascular symptoms, and (4) fear of cognitive dyscontrol. Each factor was correlated with measures of anxiety and depression, and fear of cognitive dyscontrol was most highly correlated with depression, which is broadly consistent with previous research. At pretreatment, patients with panic disorder tended to scored highest on each of the factors, compared to patients with other anxiety disorders and those with nonanxiety disorders. These findings offer further evidence that Reisss expectancy theory would benefit from revision, to incorporate the notion of a hierarchic structure of AS.

Confirmatory Factor Analysis of the Depression–Anxiety–Stress Scales in Depressed and Anxious Patients

The Depression–Anxiety–Stress Scales (DASS; P. F. Lovibond & S. H. Lovibond, 1995) have shown considerable promise in their ability to differentially assess depression and anxiety symptoms. Most of the work to date has relied on normal or predominantly anxious clinical samples. To extend this research to a predominantly depressed sample, a psychiatric sample from a mood disorders program (N = 439) was used to investigate the factor structure of the DASS. Confirmatory factor analyses indicated that a 3-factor model for the 21-item DASS was supported. A 3-factor model with crossloading items for the 42-item version showed no practical improvement. Further confirmatory analyses evaluated the ability of item subsets from the DASS to represent the constructs specified in the tripartite model (L. A. Clark & D. Watson, 1991). Strong support was obtained for the DASS to represent the construct of anhedonia and physiological hyperarousal, and their relative importance is consistent with predictions of the tripartite model in understanding the relationship between anxiety and depression.

Parental bonding and adult psychopathology: results from the US National Comorbidity Survey

BACKGROUND Research using the parental bonding instrument (PBI) has suggested that lack of parental care and/or overprotection may be important risk factors for adult mental disorders. Much of this research, however, has relied on clinical populations with one or two disorders, or has used highly select community samples. METHOD The association between parenting experiences and the occurrence of 13 common mental disorders in adulthood was evaluated in the US National Comorbidity Survey (N = 5877). The effect of sociodemographic variables (age, education, income) was statistically controlled and the effects of six parenting variables (maternal and paternal care, overprotection and authoritarianism) were examined simultaneously. The effects in men and women were examined separately. RESULTS Lack of care was the parenting variable most consistently associated with adult psychopathology. Parenting experiences with ones mother were more consistently associated with adult mental disorders. In general the impact of parenting was diagnostically non-specific. However, there appeared to be some unique effects for externalizing disorders (substance use disorders and antisocial personality disorder) in males; paternal overprotection and authoritarianism conferred a reduced risk of externalizing disorders in adult males. The overall impact of parenting as assessed by the PBI was modest, accounting for about 1 to 5 % of the variance in the occurrence of adult mental disorders. CONCLUSION Parenting experiences, particularly lack of care, are potentially causally related in a non-specific manner to a wide variety of forms of adult psychopathology in both men and women. The overall magnitude of the effect is small but statistically significant in a nationally representative US sample.

Associations of obesity with psychiatric disorders and suicidal behaviors in a nationally representative sample

OBJECTIVE To determine whether obesity is associated with a variety of psychiatric outcomes after taking into account physical health conditions. METHODS Data came from the public use dataset of the Canadian Community Health Survey Cycle 1.2 (age 15 years and older, N=36,984). Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition psychiatric diagnoses of major depressive disorder, mania, panic attacks, panic disorder, social phobia, agoraphobia, alcohol dependence, and drug dependence were examined, as was suicidal behavior (ideation or attempts). Multiple logistic regression was utilized to examine the association between obesity (defined as body mass index >or=30) and mental health outcomes. Covariates in the regressions included sociodemographic factors and a measure of physical illness burden (the Charlson Comorbidity Index). RESULTS In adjusted models, obesity was positively related to several lifetime psychiatric disorders (depression, mania, panic attacks, social phobia, agoraphobia without panic disorder), any lifetime mood or anxiety disorder, suicidal ideation, and suicide attempts [adjusted odds ratio (AOR) range: 1.22-1.58]. Obesity was similarly positively associated with past-year depression, mania, panic attacks, social phobia, any anxiety disorder, and suicidal ideation (AOR range: 1.24-1.52), and negatively associated with past-year drug dependence (AOR=0.53, 95% CI 0.31-0.89). Most of these associations were found to be specific to women, while some were also present in men. CONCLUSION Independent of physical health conditions, obesity was associated with psychiatric disorders and suicidal behavior in the Canadian population. Possible mechanisms and clinical implications of these findings are considered.

Does co-morbid depressive illness magnify the impact of chronic physical illness? A population-based perspective

OBJECTIVE To examine the relative and combined impact of depressive and chronic physical conditions on functional status and health-care use in the general population. METHOD Canadian, representative, population-based cross-sectional survey (n=130,880). Major depressive disorder (MDD) in the past 12 months was assessed by structured interview, and physical disorders, activity reduction, role impairment and work absence by self-report. The relative impact of MDD and six common chronic physical illnesses (asthma, arthritis, back problems, chronic obstructive pulmonary disease, heart disease and diabetes) was estimated using multivariate regression, adjusting for sociodemographic characteristics and overall chronic physical illness burden. RESULTS After adjusting for sociodemographic characteristics, alcohol dependence and chronic physical illness burden, the presence of co-morbid MDD was associated with significantly greater (approximately double the) likelihood of health-care utilization and increased functional disability and work absence compared to the presence of a chronic physical illness without co-morbid MDD. This impact of MDD was seen across each of the six chronic physical illnesses examined in this study, with the strongest associations seen for work absence. CONCLUSIONS These observations confirm prior findings of a strong association at the population level between major depression and health-care use and role impairment among persons with chronic physical disorders. They also point to the significant impact of co-morbid major depression on health-care seeking, disability and work absence in persons with chronic physical illness, underscoring the need for greater efforts to design and test the impact of detection and treatment programs for such individuals.

Mental Health Correlates of Intimate Partner Violence in Marital Relationships in a Nationally Representative Sample of Males and Females

It is important to understand the epidemiology of intimate partner violence (IPV) experienced by both males and females. Data were drawn from the U.S. National Comorbidity Survey Replication. The relationships between physical IPV and child abuse, mental disorders, and suicidal ideation and attempts among males and females were examined. The results indicate that child sexual abuse was associated with IPV among males, whereas child physical and sexual abuse was associated with IPV among females. IPV was associated with poor mental health outcomes for males and females, although sex differences are noted. The sex differences indicate that females experience a wider range of poor mental health outcomes compared to males. Knowledge about correlates of IPV can be useful in identifying individuals exposed to violence. Further research is required to identify effective methods to reduce exposure to IPV and to adequately address the specific needs of male and female victims of IPV.