Alexithymia: a relevant psychological variable in near-fatal asthma.

Alexithymia is a psychological trait characterised by difficulty in perceiving and expressing emotions and body sensations. Failure to perceive dyspnoea could lead alexithymic asthmatics to underestimate the severity of an asthma exacerbation, and thereby increase the risk of developing a fatal or near-fatal asthma (NFA) attack. The objective of the present study was to determine the prevalence of alexithymia in NFA patients and to analyse their clinical characteristics. Alexithymia was assessed using the Toronto Alexithymia Scale in this multicentric prospective observational study. From 33 Spanish hospitals, 179 NFA patients and 40 non-NFA patients, as a control group, were enrolled. There was a higher proportion of alexithymia in the NFA group than in the non-NFA group (36 versus 13%). Patients with NFA and alexithymia were older than the rest of the NFA group, and had a lower level of education, a higher level of psychiatric morbidity, a higher proportion of severe persistent asthma and a greater number of prior very severe asthma exacerbations (49 versus 27%). Alexithymia, severe persistent asthma and a low level of education were identified as independent variables related to repeated very severe asthma exacerbations. The results show that alexithymia is more frequent in near-fatal asthma patients compared to the rest of asthmatics and is associated with recurrent very severe asthma exacerbations.

Evaluation of a portable respiratory recording device for detecting apnoeas and hypopnoeas in subjects from a general population.

This study was designed to validate a new home portable respiratory recording device (PRRD) to identify sleep apnoea and hypopnoea in a group of subjects (n=116), from a sample of the general population. Full night polysomnography (PSG) was used as the gold standard and simultaneously performed with PRRD. PRRD measurements included oronasal airflow (thermistry), chest wall impedance, oxygen saturation, snoring and body position. The sensors were unique for each recording system. Data obtained was blindly reviewed and analysed. A high level of agreement between both methods apnoea/hypopnoea index by PSG and the respiratory disturbance index (RDI) by PRRD was observed. Accuracy of the PRRD was evaluated in terms of sensitivity and specificity for different RDI-PRRD cut-off points with respect to AHI-PSG >10 and AHI-PSG >30. A logistic regression model was performed to estimate the chance per unit of RDI of apnoeas. A received operating characteristic (ROC) curve was drawn to obtain the sensitivity/specificity profile for each observed RDI value obtained. From the ROC curve the authors identified the better cut-off points, which represent a balanced sensitivity/specificity. Through a classification table defined by the cut-off point, the post-odds to exhibit the disease was calculated. For a full PSG cut-off point of 10 a PRRD of six showed a balanced sensitivity of 95% and a specificity of 92%. For a full PSG cut-off point of 30 a PRRD of 16 shows a balanced sensitivity/specificity (100% and 97%, respectively). Post odds of apnoea were calculated for each cut-off point. In conclusion, these data suggest that the portable respiratory recording device is an effective device to identify apnoeas and hypopnoeas in a general population and is therefore a suitable device to be used in epidemiological studies.

Exercise-induced airways narrowing and exposure to environmental tobacco smoke in schoolchildren.

A case-control study of exercise-induced airways narrowing (EIAN) and exposure to environmental tobacco smoke has been carried out in Mataró, Spain. This study followed a prevalence study on EIAN performed on a random sample of 2,056 schoolchildren aged 9-14 years. Cases were 136 children having a decrease in postexercise peak expiratory flow rate equal to or greater than 15%; two controls per case, matched by sex, age, and classroom, were selected among children with a negative EIAN test. A complete history of environmental tobacco smoke exposure was collected from the parents by means of a questionnaire. Exposure from the mother was associated with EIAN in children (odds ratio = 2.23, 95% confidence interval 1.06-4.69) compared with those never exposed. Regarding the duration, intensity, and cumulative exposure, there is an overall tendency for the more heavily exposed to be at greater risk. Other sources of environmental tobacco smoke exposure at home showed no effect on EIAN in children. The results of our study do not seem to be confounded by antecedents of parental asthma or a previous diagnosis of asthma in children, and they suggest that environmental tobacco smoke exposure could play a role as a determinant of the occurrence of EIAN in children.

Prevalence of exercise-induced airway narrowing in schoolchildren from a Mediterranean town.

A cross-sectional study was carried out on a random sample of 2,216 schoolchildren 9 to 14 yr of age to determine the prevalence of exercise-induced airway narrowing (EIAN) in a Mediterranean town (Mataró). A complementary case-control study measured the association between EIAN and respiratory symptoms. A free-running test was performed during school time. Peak expiratory flow rate (PEFR) was measured at rest and at 2, 5, 10, and 15 min after exercise. A total of 136 of 2,056 satisfactory runs showed a decrease of PEFR equal to or higher than 15% at each of these times after exercise. Five more children developed wheezing during running and were considered to have EIAN. Prevalence of EIAN was 6.9% (95% CI = 5.9 to 7.9). Prevalence decreased progressively with age. No sex difference was found. In the case-control study a questionnaire of respiratory symptoms was applied to the mothers of hyperresponsive children, as well as to two matched control subjects for each case. Questionnaire analysis showed a strong association between EIAN and respiratory symptoms or rhinitis. Association with bronchitis before 2 yr of age and parental asthma was less but significant.