Role of bronchial hyperresponsiveness in patients with obstructive sleep apnea with asthma-like symptoms.

BACKGROUND: Obstructive sleep apnea (OSA) is one of the major co-morbidities and aggravating factors of asthma. In OSA-complicated asthma, obesity, visceral fat, and systemic inflammation are associated with its severity, but the role of bronchial hyperresponsiveness (BHR) is unclear. We investigated the involvement of BHR and mediastinal fat width, as a measure of visceral fat, with OSA severity in patients with OSA and asthma-like symptoms. METHODS: Patients with OSA who underwent BHR test and chest computed tomography scan for asthma-like symptoms were retrospectively enrolled. We evaluated the relationship between apnea-hypopnea index (AHI) and PC20 or anterior mediastinal fat width, stratified by the presence or absence of BHR. RESULTS: OSA patients with BHR (n = 29) showed more obstructive airways and frequent low arousal threshold and lower mediastinal fat width, and tended to show fewer AHI than those without BHR (n = 25). In the overall analysis, mediastinal fat width was significantly positively correlated with AHI, which was significant even after adjustment with age and gender. This was especially significant in patients without BHR, while in OSA patients with BHR, there were significant negative associations between apnea index and airflow limitation, and hypopnea index and PC20. CONCLUSIONS: Risk factors for greater AHI differed depending on the presence or absence of BHR in OSA patients with asthma-like symptoms. In the presence of BHR, severity of asthma may determine the severity of concomitant OSA.

A scoring algorithm for predicting the presence of adult asthma: a prospective derivation study.

BACKGROUND: To predict the presence of asthma in adult patients with respiratory symptoms, we developed a scoring algorithm using clinical parameters. METHODS: We prospectively analysed 566 adult outpatients who visited Kinki University Hospital for the first time with complaints of nonspecific respiratory symptoms. Asthma was comprehensively diagnosed by specialists using symptoms, signs, and objective tools including bronchodilator reversibility and/or the assessment of bronchial hyperresponsiveness (BHR). Multiple logistic regression analysis was performed to categorise patients and determine the accuracy of diagnosing asthma. RESULTS: A scoring algorithm using the symptom-sign score was developed, based on diurnal variation of symptoms (1 point), recurrent episodes (2 points), medical history of allergic diseases (1 point), and wheeze sound (2 points). A score of >3 had 35% sensitivity and 97% specificity for discriminating between patients with and without asthma and assigned a high probability of having asthma (accuracy 90%). A score of 1 or 2 points assigned intermediate probability (accuracy 68%). After providing additional data of forced expiratory volume in 1 second/forced vital capacity (FEV(1)/FVC) ratio <0.7, the post-test probability of having asthma was increased to 93%. A score of 0 points assigned low probability (accuracy 31%). After providing additional data of positive reversibility, the post-test probability of having asthma was increased to 88%. CONCLUSIONS: This pragmatic diagnostic algorithm is useful for predicting the presence of adult asthma and for determining the appropriate time for consultation with a pulmonologist.

Comparison of the Asthma Health Questionnaire-33-Japan and the short-form 36-item health survey for measuring quality of life in Japanese patients with asthma.

BACKGROUND: The Asthma Health Questionnaire (AHQ)-Japan is useful for assessing quality of life (QOL) in Japanese patients with asthma. However, no studies have compared the AHQ-Japan to other QOL instruments. METHODS: The AHQ-33-Japan and the Medical Outcomes Study Short-Form 36-Item Health Survey (SF-36) were completed simultaneously by 126 Japanese patients with asthma (48 men, 78 women; 58.1 +/- 17.3 years of age), and the data were compared. RESULTS: Poor negative correlations (correlation coefficient (r) = -0.20 to -0.44, P < 0.05) were observed for 38 combinations of the subscales of these QOL instruments. As the severity of the patients' asthma increased, the scores of most subscales of both QOL instruments became worse. However, the AHQ-33 was more sensitive for severity than the SF-36. On logistic regression analysis, high Asthmatic Symptoms, Factors which Worsened Symptoms, Emotion, Daily Activity, and Social Activity subscale scores, as well as a high total 32-item score, of the AHQ-33 were associated with an increased risk of moderate to severe asthma. On the other hand, only the Physical functioning subscale score of the SF-36 was associated with an increased risk of moderate to severe asthma. CONCLUSIONS: Our results show that the AHQ-33 is useful as a disease-specific QOL instrument in Japanese patients with asthma and that it is better than the SF-36, which is a generic QOL instrument. In the future, the AHQ-33 should be compared to other asthma-specific questionnaires.

Usefulness of QVAR for the treatment of bronchial asthma--with and without use of an inhalation device.

The treatment of bronchial asthma with QVAR (hydrofluoroalkane-134a BDP; 3M Pharmaceuticals, St. Paul, MN, USA) is usually conducted without an inhalation assistance device. However, Japanese patients who experience difficulty in coordinating activation with inspiration of inhaled steroid drugs are instructed on the use of such a device. We therefore examined the necessity of using an inhalation assistance device (INSPIR-EASE, IE) and its effect on quality of life (QOL) in the treatment of patients with bronchial asthma taking QVAR. Hence, lung function and QOL associated with taking QVAR plus IE or QVAR alone were examined by a cross-over method in 44 bronchial asthma patients (STEP 2 or 3) over 20 years of age. In all patients, lung function tests conducted 12 weeks after start of treatment indicated significant improvements of forced expiratory volume in 1 second (FEV1) with QVAR alone compared with QVAR plus IE (p < 0.05). In patients less than 70 years of age, significant improvements of forced vital capacity (FVC) and nitric oxide (NO) were also observed with QVAR alone compared with QVAR plus IE (p < 0.05). Examination of QOL the Living with Asthma Questionnaire indicated that medication usage was significantly improved with QVAR alone compared with QVAR plus IE. Significant improvement of FEV1 was observed with QVAR alone compared with QVAR plus IE, and additionally in patients less than 70 years of age improvement of FVC and NO was also marked. This study confirmed the usefulness of QVAR alone in patients with bronchial asthma.

[Use of transport medium in sputum bacterial culture examination of lower airway infection].

Our medical institution does not have a bacterial culture facility, requiring outsourcing of bacterial culture tests. Due to the time elapsed from the time of specimen collection to culturing, the identification of causative bacteria in respiratory tract infections tends to be difficult. We therefore used transport medium for sputum bacteria examinations. Expectorated purulent or purulent-mucous sputum specimens were collected from 32 patients with lower respiratory tract infection. We divided each of the sputum specimens into the two treatment groups: transport medium (Seedswab gamma2) ndar and stad disinfection container. Paired samples prepared from each patient were sent out for bacterial culture together. The time elapsed from collection to delivery to the lab were as follows: day 0 (same day, n = 14 patients), day 1 (n = 15), day 2 (n = 2), and day 3 (n = 1). The identified causative bacteria were Streptococcus pneumoniae (n = 6 patients), Haemophilus influenzae (n =5), Pseudomonas aeruginosa (n = 4), Staphylococcus aureus (n = 2), Moraxella catarrhalis (n = 2), Klebsiella pneumoniae (n = 1), and Streptococcus agalactiae (n = 1). Samples prepared by each of the two methods gave similar results. The utility of transport medium for examination of general bacteria for lower airway infection from sputum samples was not demonstrated. The rate of detection of bacteria decreased, when the transport of samples was delayed. Therefore, we need to send the sputum specimens as quickly as possible.

Role of muscarinic acetylcholine receptors in a guinea pig model of asthma.

We examined the density of muscarinic acetylcholine receptor (mACh-R) subtypes (M1R, M2R and M3R) in guinea pig lung. The density of M3R in the lung tissue of ovalbumin (OA)-sensitized guinea pigs was higher than that in the control group. However, no difference was observed in the affinity of M3R between the sensitized and the control lungs. No difference was observed in the density and affinity of M1R and M2R in sensitized and control lungs. Pilocarpine, which is an M2R stimulant, increased the density of M3R in the lung tissue and the rate of the increase in sensitized guinea pigs was less than that in the control group. In contrast, methoctranine, which is an M2R antagonist, decreased the density of M3R and the rate ofthis decrease was the same in the sensitized and control groups. These results suggest that, in OA-sensitized guinea pigs, a dysfunction of M2R leads to the abnormal density of M3R.