Hypocapnia associated with cardiac stress scintigraphy in chest pain patients with panic disorder

The association between panic disorder and coronary artery disease among primary care patients presenting with chest pain: an updated literature review

CONTEXT

Although panic disorder is linked to hypertension and smoking, the relationship between panic disorder and coronary artery disease (CAD) is unclear.

OBJECTIVE

To extend our understanding about the strength of the association between panic disorder and coronary artery disease and known cardiovascular risk factors.

DATA SOURCES

Potential studies were identified via a computerized search of MEDLINE and PsycINFO databases and review of bibliographies. MeSH headings used included panic disorder with chest pain, panic disorder with coronary disease or cardiovascular disorders or heart disorders, and panic disorder with cholesterol or essential hypertension or tobacco smoking.

STUDY SELECTION

The diagnosis of panic disorder in eligible studies was based on DSM-IV criteria, and studies must have used objective criteria for CAD and risk factors. Only case-control and cohort studies were included.

DATA SYNTHESIS

Concerning the relationship between panic disorder and CAD, studies conducted in emergency departments found a relative risk [RR] of 1.25 (95% CI = 0.87 to 1.80), while those conducted in cardiology settings found an inverse relationship (RR = 0.19, 95% CI = 0.10 to 0.37). However, there is an inverse relationship between the prevalence of CAD in the study and the RR (r = -.554, p = .097), suggesting that, in primary care settings in which the prevalence of CAD is low, there may be a significant association between panic disorder and CAD.

CONCLUSION

The association between panic disorder and CAD has several implications for primary care physicians managing patients with chest pain. When comorbid, the panic attacks may cause the patient with coronary disease to seek care but could also provoke a cardiac event. If one condition is recognized, a search for the other may be warranted because of the potential consequences if left undetected. The treatment approach to the panic disorder should be adjusted in the presence of comorbid CAD.

Elevated brain lactate responses to neural activation in panic disorder: a dynamic 1H-MRS study

Converging evidence suggests that patients with panic disorder have a metabolic disturbance that may influence the regulation of arousal systems and confer vulnerability to 'spontaneous' panic attacks. The consistent finding of elevated brain lactate responses to various metabolic challenges in panic disorder appears to support this model, although the mechanism of this effect is not understood. Several mechanisms have been proposed to account for elevated brain lactate responses in panic disorder, including (1) brain hypoxia due to excessive cerebral vasoconstriction, and (2) a metabolic disturbance affecting lactate metabolism. Recent studies have shown that neural activation (for example, sensory stimulation) causes local lactate accumulation in the presence of increased oxygen availability. The current study used proton magnetic resonance spectroscopic measures of visual cortex lactate changes during visual stimulation in 15 untreated patients with panic disorder and 15 matched volunteers to critically test these two proposed mechanisms of elevated brain lactate responses in panic disorder. Visual cortex lactate/N-acetylaspartate increased during visual stimulation in both groups. The increase was significantly greater in the panic patients than in the comparison group. There were no group differences in end-tidal pCO(2). The finding that visual stimulation leads to significantly greater visual cortex lactate responses in panic patients is not predicted by the hypoxia model. These results suggest that a metabolic disturbance affecting the production or clearance of lactate is the cause of the elevated brain lactate responses consistently observed in panic disorder and provide further support for metabolic models of vulnerability to this illness.

Difficulties in screening for adjustment disorder, Part I: Use of existing screening instruments in cancer patients undergoing bone marrow transplantation

OBJECTIVE

Although success rates for bone marrow transplantation (BMT) continue to improve, there is still a high level of morbidity and physical and emotional distress associated with BMT. To date, limited research has focused on the assessment of and screening for specific psychiatric disorders of patients facing BMT. This is especially true with regard to identifying adjustment disorder (AD), despite the fact that AD is the most prevalent psychiatric diagnosis in cancer patients.

METHODS

A sample of 95 BMT patients were interviewed using the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, 4th edition (SCID) and completed several commonly used self-report instruments to determine if these tools could be used to identify patients with adjustment disorder in need of further assessment and intervention.

RESULTS

Of these patients, 34.7% were diagnosed with adjustment disorder, 11.6% with major depression, and 5.3% with generalized anxiety disorder. The instruments were not found to be predictive of AD. However, the results of a regression analysis showed that the Social Subscale of the Functional Assessment of Cancer Therapy-General (R2 delta = 0.04, F = 4.30, p < 0.05) was a significant predictor of adjustment disorder.

SIGNIFICANCE OF RESULTS

We conclude that there is little efficacy in using existing scales for detecting adjustment disorders in cancer patients undergoing bone marrow transplantation, and that other tools for identifying patients with adjustment disorder who might benefit from counseling are needed.

Treatment of noncardiac chest pain of psychological origin

Psychiatric comorbidity is not an uncommon phenomenon in patients with noncardiac chest pain (NCCP). Panic disorder seems to be the most important psychiatric comorbidity for a number of reasons. First, it is the most common psychiatric disorder associated with NCCP. Second, panic disorder is a highly treatable condition that can produce dramatic improvement of NCCP when treatment is appropriate. Finally, the treatment of psychiatric comorbidity, whether panic disorder or other psychiatric disorders, can pay significant dividends in terms of improving the patient's overall well-being and adaptation to illness, even if his/her chest pain symptoms are not alleviated. Adopting a biopsychosocial model to intervene on the stress of these patients' experience is a key concept that can make NCCP a much less formidable challenge for the gastroenterologist.

Difficulties in screening for adjustment disorder, Part II: An attempt to develop a novel self-report screening instrument in cancer patients undergoing bone marrow transplantation

Objective: Screening for adjustment disorder (AD) in cancer patients presents a significant clinical challenge. As seen in Part I of this research, conventional, existing measures are rather poor at detecting this most common of psychiatric diagnoses. Bone marrow transplantation (BMT) has a high level of morbidity that can cause significant stress for patients faced with the procedure.

Methods: A sample of 95 BMT patients completed a semistructured interview and a novel self-report instrument, the Coping Flexibility Scale for Cancer (C-Flex), to determine if it could identify patients with adjustment disorder in need of further assessment and intervention.

Results: The screen yielded four factors but was not predictive of AD. However, the C-Flex was significantly related to the presence of any disorder (r = −0.44, p < 0.001) in this sample. In addition, Factor I of the screen was found to be correlated to the presence of any diagnosis (r = −0.44, p < 0.001) and to have adequate sensitivity (81.63%) and specificity (76.09%).

Significance of results: Either because of problems with the scale or the amorphous nature of the AD category, or both, rapid identification of patients with this common problem has proven to be elusive.

The psychological aspects of noncardiac chest pain

There is some evidence to support a psychosocial link to GERD,although it is a weak one. The little research that has been done in this area is, in general, poor and inconclusive. Better designed studies must be done. The elements that seem to offer the best possibilities for research in GERD are the psychological variables involved in care seeking and the variations between care seekers and non-care seekers. In addition, research on psychosocial predictors of response to proton pump inhibitors, prokinetic agents, and antidepressants and other pain-modulating drugs need to be better understood. The psychosocial link to NCCP is stronger with regard to panic disorder,but much research needs to be done. Despite the paucity of well done,rigorously controlled studies in NCCP patients, that there is a high prevalence of psychiatric disturbance in this group. Parental health and childhood trauma are intriguing areas for further research, particularly in light of the connection between abuse and IBS and other functional GI disorders.Finally, panic disorder has been established as an important comorbidity of NCCP. It also merits more research, particularly into the pathophysiology that may link these two disorders.

Respiratory dysregulation in anxiety, functional cardiac, and pain disorders. Assessment, phenomenology, and treatment

Respiration is a complex physiological system affecting a variety of physical processes that can act as a critical link between mind and body. This review discusses the evidence for dysregulated breathing playing a role in three clinical syndromes: panic disorder, functional cardiac disorder, and chronic pain. Recent technological advances allowing the ambulatory assessment of endtidal partial pressure of CO2 (PCO2) and respiratory patterns have opened up new avenues for investigation and treatment of these disorders. The latest evidence from laboratories indicates that subtle disturbances of breathing, such as tidal volume instability and sighing, contribute to the chronic hypocapnia often found in panic patients. Hypocapnia is also common in functional cardiac and chronic pain disorders, and studies indicate that it mediates some of their symptomatology. Consistent with the role of respiratory dysregulation in these disorders, initial evidence indicates efficacy of respiration-focused treatment.

Psychologic and psychiatric aspects of gastrointestinal disease

There has been an explosion in understanding of the psychosocial concomitants of functional gastrointestinal disorders. Detecting psychologic disturbance and eliciting a history of physical or sexual abuse are critical in suggesting comprehensive and efficacious treatment strategies for these patients. The challenge is to define further the use of psychopharmacologic agents, including the newer antidepressants, anticonvulsants, and anxiolytic agents, in the treatment of chronic functional gastrointestinal disorders. Further research to evaluate the usefulness of various forms of psychotherapeutic and behavioral interventions needs to be undertaken. Establishing a multicomponent treatment program delivered by a team of caregivers, each bringing their unique skills (internist, psychiatrist, psychologist, and others) to patients, must be based on further research on the efficacy of these modalities as opposed to empiric treatment.