Impact of Panic Attacks on Bronchoconstriction and Subjective Distress in Asthma Patients With and Without Panic Disorder.

OBJECTIVE: Panic disorder (PD) is common among asthma patients and is associated with worse asthma outcomes. This may occur because of psychophysiological factors or cognitive/affective factors. This study evaluated the impact of panic attacks (PAs) on bronchoconstriction and subjective distress in people who have asthma with and without PD. METHODS: A total of 25 asthma patients (15 with PD who had a PA [PD/PA], 10 without PD who did not have a PA [no PD/no PA]) were recruited from an outpatient clinic. They underwent a panic challenge (one vital capacity inhalation of 35% carbon dioxide [CO2]) and completed the Panic Symptom Scale, the Subjective Distress Visual Analogue Scale, and the Borg Scale before and after CO2. Forced expiratory volume in 1 second was assessed pre- and post-CO2; respiratory (i.e., CO2 production, minute ventilation, tidal volume) was continuously recorded, and physiological measures (i.e., systolic and diastolic blood pressure [SBP/DBP]) were recorded every 2 minutes. RESULTS: Analyses adjusting for age, sex, and provocative concentration of methacholine revealed no significant differences between groups in forced expiratory volume in 1 second change after CO2 inhalation (F(1, 23) < 0.01, p = .961). However, patients with PD/PA reported more panic (F(1, 22) = 18.10, p < .001), anxiety (F(1, 22) = 21.93, p < .001), worry (F(1, 22) = 26.31, p < .001), and dyspnea (F(1,22) = 4.68, p = .042) and exhibited higher levels of CO2 production (F(1, 2843) = 5.89, p = .015), minute ventilation (F(1, 2844) = 4.48, p = .034), and tidal volume (F(1, 2844) = 4.62, p = .032) after the CO2 challenge, compared with patients with no PD/no PA. CONCLUSIONS: Results, presented as hypothesis generating, suggest that asthma patients with PD/PA exhibit increased panic-like anxiety, breathlessness, and a respiratory pattern consistent with hyperventilation that was not linked to statistically significant drops in bronchoconstriction.

Do asthma patients with panic disorder really have worse asthma? A comparison of physiological and psychological responses to a methacholine challenge.

BACKGROUND: Panic disorder (PD) has been linked to worse asthma outcomes. Some suggest that asthmatics with PD have worse underlying asthma; others argue that worse outcomes are a result of their tendency to over-report symptoms. This study aimed to measure physiological and psychological responses to a simulated asthma attack (methacholine challenge test: MCT) in asthmatics with and without PD. METHODS: Asthmatics with (n = 19) and without (n = 20) PD were recruited to undergo a MCT. Patients completed subjective symptom questionnaires (Panic Symptom Scale, Borg Scale) before and after a MCT. Physiological measures including heart rate (HR), and systolic and diastolic blood pressure (SBP/DBP) were also recorded. RESULTS: Analyses, adjusting for age and sex, revealed no difference in methacholine concentration required to induce a 20% drop in forced expiratory volume in one second (FEV1: F = 0.21, p = .652). However, PD patients reported worse subjective symptoms, including greater ratings of dyspnea (F = 8.81, p = .006) and anxiety (F = 9.44, p = .004), although they exhibited lower levels of physiological arousal (i.e., HR, SBP/DBP). An interaction effect also indicated that PD, relative to non-PD, patients reported more panic symptoms post-MCT (F = 5.05, p = .031). CONCLUSIONS: Asthmatics with PD report higher levels of subjective distress, despite exhibiting lower levels of physiological arousal, with no evidence of greater airway responsiveness. Results suggest that worse outcomes in PD patients may be more likely due to a catastrophization of bodily symptoms, rather than worse underlying asthma. Interventions designed to educate patients on how to distinguish and manage anxiety in the context of asthma are needed.

Mediator effect of depressive symptoms on the association between BMI and asthma control in adults.

BACKGROUND: Obesity has been associated with worse asthma control. Depression has also been shown to be disproportionally prevalent among patients with asthma and among patients with obesity. However, no studies have examined the mediating effect of depression on the obesity-asthma relationship. This study examined the extent to which depressive symptoms may mediate the obesity-asthma relationship in an adult sample. METHODS: A total of 798 patients with physician-diagnosed asthma were recruited from the outpatient asthma clinic at Hôpital du Sacré-Cœur de Montréal. Patients provided demographic and medical history information and completed a battery of questionnaires, including the Beck Depression Inventory (BDI)-II and the Asthma Control Questionnaire (ACQ). BMI was calculated from self-reported height and weight. RESULTS: Analyses adjusted for age, sex, years of education, cohabitation, and inhaled corticosteroid dose revealed an association between BMI and ACQ (ß = 0.017, P = .026), between BMI and BDI-II (ß = 0.189, P = .002), and between BDI-II and ACQ (ß = 0.044, P < .001). However, when both BDI-II and BMI were entered into the same model, BDI-II (ß = 0.044, P < .001) but not BMI (ß = 0.009, P = .226) remained significantly associated with ACQ. CONCLUSIONS: The results indicate that depression and a high BMI are both associated with worse asthma control. However, consistent with our hypotheses, the relationship between BMI and worse asthma control was mediated by depressive symptoms. Future studies should examine the precise role of depressive symptoms in both weight and asthma control.

The impact of body mass index on inpatient- versus outpatient-treated chronic obstructive pulmonary disease exacerbations.

BACKGROUND: Increased body weight has been associated with worse prognoses for many chronic diseases; however, this relationship is less clear in patients with chronic obstructive pulmonary disease (COPD), with underweight patients experiencing higher morbidity than normal or overweight patients. OBJECTIVE: To assess the impact of body mass index (BMI) on the risk for COPD exacerbations. METHODS: The present study included 115 patients with stable COPD (53% women; mean [± SD] age 67±8 years). Height and weight were measured to calculate BMI. Patients were followed for a mean of 1.8±0.8 years to assess the prospective risk of inpatient-treated exacerbations and outpatient-treated exacerbations, all of which were verified by chart review. RESULTS: Cox regression models revealed that underweight patients were at greater risk for inhospital-treated exacerbations (RR 2.93 [95% CI 1.27 to 6.76) relative to normal weight patients. However, overweight (RR 0.59 [95% CI 0.33 to 1.57) and obese (RR 0.99 [95% CI 0.53 to 1.86]) patients did not differ from normal weight patients. All analyses were adjusted for age, sex, length of diagnosis, smoking pack-years, forced expiratory volume in 1 s, and time between recruitment and last exacerbation. BMI did not influence the risk of out-of-hospital exacerbations. CONCLULSIONS: The present study showed that underweight patients were at greater risk for inhospital exacerbations. However, BMI did not appear to be a risk factor for out-of-hospital exacerbations. This suggests that the BMI-exacerbation link may differ according to the nature of the exacerbation, the mechanisms for which are not yet known.

Individual and combined impact of cigarette smoking, anxiety, and mood disorders on asthma control.

INTRODUCTION: Despite the availability of effective therapies, research indicates that more than 50% of asthmatics are poorly controlled. Poor asthma control has been linked to behavioral (i.e., cigarette smoking) and psychological factors (i.e., anxiety and depression). However, little is known about the individual versus combined impact of cigarette smoking and anxiety or mood disorders in adult asthmatics on asthma control. METHODS: A total of 796 confirmed adult asthma patients completed a sociodemographic and medical history interview and underwent a psychiatric interview using the Primary Care Evaluation of Mental Disorders. Asthma control was evaluated using the Asthma Control Questionnaire. RESULTS: After adjusting for age, sex, and dose of inhaled corticosteroids, general linear model analyses indicated a significant main effect of current smoking on asthma control (B [SE] = 0.156 [0.059], p = .008) and main effects of anxiety disorders (B [SE] = 0.408 [0.095], p = < .001) and mood disorders (B [SE] = 0.448 [0.098], p = < .001) on asthma control. Pack-years were not associated with asthma control, and there were no interaction effects of current smoking or pack-years with either anxiety or mood disorders on asthma control. CONCLUSIONS: Findings suggest that current smoking, having an anxiety disorder, and having a mood disorder are independently associated with poorer asthma control but that cumulative smoking history (i.e., pack-years) was not associated with worse asthma control. These results indicate that smoking cessation may have a positive impact on asthma control levels in spite of past smoking intensity and highlight the importance of interventions that target anxiety and mood disorders in adult asthmatics.

Association between generalized anxiety disorder and asthma morbidity.

BACKGROUND: Generalized anxiety disorder (GAD) is common among people with asthma, but its association with asthma morbidity remains unexplored. This study examined cross-sectional associations between GAD and asthma control, quality of life, and self-efficacy. METHODS: Seven hundred ninety-four adults with confirmed asthma were recruited from the outpatient clinic of a university hospital. Patients underwent a sociodemographic and medical history interview (to assess health service use and medications), followed by a brief psychiatric interview (Primary Care Evaluation of Mental Disorders) to assess GAD. Patients completed questionnaires assessing asthma control, quality of life, and asthma self-efficacy and underwent spirometry. General linear models and logistic regression were used to assess associations between GAD and asthma morbidity measures, adjusting for covariates. RESULTS: GAD affected 4% of the sample. The analyses revealed significant associations between GAD and worse overall asthma control (ß = 0.62, standard error [SE] = 0.18, p < .001), increased bronchodilator use (ß = 10.60, SE = 2.64, p < .001), worse asthma quality of life (ß = -0.91, SE = 0.23, p < .001), and worse asthma self-efficacy (ß = -59.56, SE = 13.59, p < .001) after the adjustment for covariates. Separate sensitivity analyses including major depressive disorder and asthma self-efficacy as additional covariates rendered many of these associations nonsignificant. There were no associations between GAD and emergency visits or hospitalizations. CONCLUSIONS: GAD is associated with worse asthma morbidity independent of age, sex, smoking, and asthma severity; however, comorbid major depressive disorder and low asthma self-efficacy may account for many of these associations. Only breathlessness and the frequency of bronchodilator use were uniquely associated with GAD. Future research should examine whether treatment of GAD can affect asthma outcomes.