Dyspnea and symptom amplification in asthma

Changes in insomnia severity with advanced PAP therapy in patients with posttraumatic stress symptoms and comorbid sleep apnea: a retrospective, nonrandomized controlled study

BACKGROUND

Sleep disorders frequently occur in posttraumatic stress disorder (PTSD) patients. Chronic insomnia is a common feature of and criteria for the diagnosis of PTSD. Another sleep disorder, obstructive sleep apnea (OSA), also occurs frequently in PTSD, and emerging research indicates OSA fuels chronic insomnia. Scant research has investigated the impact of OSA treatment on insomnia outcomes (Insomnia Severity Index, ISI) in trauma survivors.

METHODS

OSA patients with moderately severe posttraumatic stress symptoms were studied in a retrospective chart review. Ninety-six patients who failed CPAP therapy due to expiratory pressure intolerance or complex sleep apnea or both underwent manual titration with advanced PAP modes [autobilevel (ABPAP); adaptive servo-ventilation (ASV)], which were subsequently prescribed. PAP use measured by objective data downloads divided the sample into three groups: compliant regular users (C-RU): n = 68; subthreshold users (SC-RU): n = 12; and noncompliant users (NC-MU): n = 16. The average follow-up was 11.89 ± 12.22 months. Baseline and posttreatment ISI scores were analyzed to assess residual insomnia symptoms as well as cure rates.

RESULTS

The C-RU group showed significant improvements in insomnia with very large effects compared to those in the NC-MU reference group (P = 0.019). Insomnia severity significantly decreased in all three groups with large effects (C-RU, P = 0.001; SC-RU, P = 0.027; NC-MU, P = 0.007). Hours of weekly PAP use and insomnia severity were inversely correlated (P = 0.001, r = - 0.321). However, residual insomnia symptoms based on established ISI cut-offs were quite common, even among the C-RU group. Post hoc analysis showed that several categories of sedating medications reported at baseline (hypnotics, anti-epileptic, opiates) as well as actual use of any sedating medication (prescription or nonprescription) were associated with smaller insomnia improvements than those in patients not using any sedating agents.

CONCLUSIONS

In a retrospective, nonrandomized analysis of a select sample of sleep clinic patients with OSA and PTSD symptoms, advanced PAP therapy was associated with significant improvement in insomnia severity for both compliant and partial users. However, residual insomnia symptoms persisted, indicating that PAP therapy provides only limited treatment. RCTs are warranted to assess the effect of ABPAP and ASV modes of therapy on adherence and sleep outcomes, and their potential impact on posttraumatic stress symptoms. Treatment arms that combine PAP with CBT-I would be expected to yield the greatest potency.

Somatosensory amplification - An old construct from a new perspective

The paper reviews and summarizes the history and the development of somatosensory amplification, a construct that plays a substantial role in symptom reports. Although the association with negative affect has been supported by empirical findings, another key elements of the original concept (i.e. body hypervigilance and the tendency of focusing on mild body sensations) have never been appropriately addressed. Recent findings indicate that somatosensory amplification is connected with phenomena that do not necessarily include symptoms (e.g. modern health worries, or expectations of symptoms and medication side effects), and also with the perception of external threats. In conclusion, somatosensory amplification appears to refer to the intensification of perceived external and internal threats to the integrity of the body ("somatic threat amplification") rather than amplification of perceived or actual bodily events only. Practical implications of this new approach are also discussed.

The Interpretation of Dyspnea in the Patient with Asthma

Physicians have noted dyspnea in severely ill asthmatic patients to be associated with fright or panic; in more stable patients dyspnea may reflect characteristics including lung function, personality and behavioral traits. This study evaluates the symptom of dyspnea in 32 asthmatic patients twice: first when acutely ill and again after an initial response to therapy. Spirometry was performed, dyspnea quantified (Borg scale), and panic assessed with a specialized measure of acute panic (the acute panic inventory (API)) in the 32 patients before and again after treatment. After treatment, questionnaires to evaluate somatization and panic disorder were also administered. When acutely ill, both the API and all spirometric measures (PEFR; FEV1; IC) correlated with dyspnea. Multiple linear regression showed that measures of the API, the peak expiratory flow rate, and female sex taken together accounted for 41% of dyspnea in acute asthma. After treatment, the API again predicted dyspnea while spirometric data did not. Those subjects who described themselves as having chronic panic disorder reported high grades of dyspnea after treatment also. We conclude that interpretations of the self-report of asthma differ between acutely ill and stable asthmatic patients.

Is somatosensory amplification a risk factor for an increased report of side effects? Reference data from the German general population

OBJECTIVE

The study investigates the association between somatosensory amplification and the reporting of side effects. It establishes a German version of the Somatosensory Amplification Scale and examines its psychometric properties in a representative sample of the German population.

METHODS

Sample size was 2.469, with 51% taking any medication. Participants answered the Somatosensory Amplification Scale, Generic Assessment of Side Effects Scale, and indicated whether they were taking any medication and the type of medication. Correlational analysis and binary logistic regression were performed.

RESULTS

When examining a subsample reporting both medication intake and general bodily symptoms, participants higher in somatosensory amplification rated more of their general bodily symptoms as medication-attributed side effects. However, somatosensory amplification scores were not associated with the intake of any type of medication. In the overall sample, higher somatosensory amplification scores were associated with an increased report of bodily symptoms. Additionally, participants with higher somatosensory amplification reported intake of a greater number of different medications. The psychometric properties of the translated scale were good, and previously established associations of somatosensory amplification with demographic variables (age, sex) were replicated.

CONCLUSION

Results suggest a possible attributional bias concomitant to somatosensory amplification which in turn may increase the reporting of side effects after medication intake.

The many faces of somatosensory amplification: The relative contribution of body awareness, symptom labeling, and anxiety

The questionnaire study aimed to evaluate the relative contribution of body awareness, subjective symptoms, and anxiety to the construct of somatosensory amplification in both healthy controls (n = 475) and patients visiting their general practitioner (n = 236). Regression analysis explained 52.0 percent of total variance of the somatosensory amplification scale scores. Body awareness was the most influential predictor (β = 0.489, p < 0.001) when considering all predictors simultaneously. The results suggest that dispositional interoceptive focus, as indicated by body awareness, may be an important aspect of somatosensory amplification, over and above dispositional anxiety or subjective symptom report.

Depression's influence on the Asthma Control Test, Japanese version

BACKGROUND

Depression has been linked to poorer asthma control in asthmatic patients. Although the Japanese version of the Asthma Control Test (ACT-J) is frequently used as a simple, practical evaluation tool in clinical care settings in Japan, knowledge regarding its efficacy for assessing asthma control in asthmatic patients with depression is limited. Thus, we retrospectively investigated cut-off values of the ACT-J for well-controlled asthma, and explored depression's influence on the test with a questionnaire survey.

METHODS

Data were analyzed on 1,962 adult asthmatic patients who had completed both the ACT-J and the Japanese version of the Patient Health Questionnaire-9 (J-PHQ-9) in 2008 questionnaire survey conducted by the Niigata Asthma Treatment Study Group. Patients were classified into low (LD: J-PHQ-9 score of 0-4) or high depression (HD: J-PHQ-9 score of 5-27) groups. In both groups, the efficacy of the ACT-J was confirmed. We then compared the optimal cut-off points for uncontrolled asthma in both groups by performing a receiver operating characteristic (ROC) analysis, using the original classification referred to the GINA classification as the "true" classification.

RESULTS

Cronbach's alpha in the LD and HD group was 0.808 and 0.740 respectively. In both groups, the sub-group with existence of work absenteeism or frequent attacks during the previous 12 months scored lower on the ACT-J. The area under the curve and optimal cut-off point for patients with LD and HD were 0.821 and 0.846, and 23 and 20 respectively.

CONCLUSIONS

The efficacy of the ACT-J was confirmed in depressive patients with asthma. Because asthma control as evaluated with the ACT-J can be worse than actual control under depressive states, physicians should also pay attention to a patient's depressive state at evaluation. Further investigations focus on the association between the ACT-J and depression are required.

The Asthma Control Test, Japanese version (ACT-J) as a predictor of Global Initiative for Asthma (GINA) guideline-defined asthma control: analysis of a questionnaire-based survey

BACKGROUND

The 2006 Global Initiative for Asthma (GINA 2006) guidelines emphasize the importance of evaluating the control rather than the severity of asthma. The Asthma Control Test (ACT) is well known to be an excellent tool for evaluating asthma control in the clinical setting. This study aimed to evaluate the ACT, Japanese version (ACT-J) as a predictor of asthma control as defined by the GINA 2006 guidelines in actual clinical practice.

METHODS

A cross-sectional analysis comparing the ACT-J score and GINA classification of asthma control among 419 patients of primary care physicians and specialists was performed using the data from a 2010 questionnaire-based survey conducted by the Niigata Asthma Treatment Study Group.

RESULTS

The optimal cut-off point of the ACT-J score for predicting GINA-defined asthma control was 23, with ACT-J scores of ≥23 and ≤22 predicting controlled and uncontrolled asthma with area under the receiver operating characteristics curve values of 0.76 [95% confidence interval (CI): 0.72-0.81] and 0.93 [95% CI: 0.90-0.97], respectively.

CONCLUSIONS

ACT scores of ≥23 and ≤22 are useful for identifying patients with controlled and uncontrolled asthma, respectively, as defined by GINA 2006, and the latter is more strongly predictive than the former. The reason for the higher cut-off point of the ACT-J relative to other versions of the ACT is unclear and warrants further investigation.

The hidden effects of blinded, placebo-controlled randomized trials: an experimental investigation

The knowledge of having only a 50% chance of receiving an active drug can result in reduced efficacy in blinded randomized clinical trials (RCTs) compared to clinical practice (reduced external validity). Moreover, minor onset sensations associated with the drug (but not with an inert placebo) can further challenge the attribution of group differences to drug-specific efficacy (internal validity). We used a randomized experimental study with inert placebos (inert substance) vs active placebos (inducing minor sensations), and different instructions about group allocation (probability of receiving drug: 0%, 50%, 100%). One hundred forty-four healthy volunteers were informed that a new application method for a well-known painkiller would be tested. Pain thresholds were assessed before and after receiving nasal spray. Half of the nasal sprays were inert placebos (sesame oil), while the other half were active placebos inducing prickling nasal sensations (sesame oil with 0.014% capsaicin). The major outcome was pain threshold after placebo application. A substantial expectation effect was found for the inert placebo condition, with participants who believed they had received an active drug reporting the highest pain thresholds. Active placebos show substantial differences to passive placebos in the 50% chance group. Therefore, patient expectations are significantly different in placebo-controlled clinical trials (50% chance) vs clinical practice (100% chance). Moreover, minor drug onset sensations can challenge internal validity. Effect sizes for these mechanisms are medium, and can substantially compete with specific drug effects. For clinical trials, new study designs are needed that better control for these effects.

Desempenho de uma escala analógica visual legendada na determinação do grau de dispneia durante teste de broncoespasmo induzido por exercício em crianças e adolescentes asmáticos

OBJETIVO: Existe uma relação indireta entre a obstrução das vias aéreas em asma e a intensidade de falta de ar (dispneia). Uma escala visual analógica legendada de dispneia com escore de 0-3 pontos tem sido amplamente utilizada na avaliação da broncoconstrição, embora a percepção de tal obstrução seja muito variável. O objetivo deste estudo foi determinar se crianças e adolescentes são capazes de perceber a broncoconstrição aguda induzida por exercício (BAIE), bem como medir o poder discriminatório de uma escala visual analógica legendada de dispneia em relação à intensidade de BAIE. MÉTODOS: Estudo transversal com 134 crianças e adolescentes asmáticos que foram submetidos a um teste de broncoespasmo induzido por seis minutos de exercício em um cicloergômetro. A intensidade da dispneia foi determinada utilizando-se uma escala visual analógica legendada de dispneia antes de cada determinação de VEF1. A escala tem um escore de 0-3 pontos, com desenhos em uma sequência lógica variando entre "sem sintomas" e "dispneia grave". As variáveis foram determinadas no momento basal, assim como em 5, 10 e 20 minutos após o término do teste de exercício. A acurácia da escala de dispneia em detectar o grau de BAIE foi determinada através de curvas ROC para a queda de VEF1 após o exercício, usando pontos de corte de 10%, 20%, 30% e 40%. RESULTADOS: Dos pacientes selecionados, 111 completaram o estudo, e 52 (46,8%) apresentaram BAIE. A área sob a curva ROC progressivamente aumentou com o aumento do grau de broncoconstrição. CONCLUSÕES: Em crianças e adolescentes asmáticos, a acurácia desta escala de dispneia melhora com o aumento do percentual de queda em VEF1 após o exercício. Entretanto, o valor preditivo da escala é subótimo quando a porcentagem de queda em VEF1é menor.