Sensitivity to environmental irritants and capsaicin cough reaction in patients with a positive methacholine provocation test before and after treatment with inhaled corticosteroids.

BACKGROUND: Increasing evidence points to a potential role for members of the transient receptor potential family of cation channels on several features of asthmatic disease. The cough sensitivity to inhaled capsaicin is known to reflect the reactivity of these airway sensory nerves. OBJECTIVE: The aim was to study, among patients having a positive methacholine provocation and diagnosed with asthma, capsaicin cough sensitivity, sensitivity to methacholine, and levels of exhaled nitric oxide before and after treatment with inhaled steroids, and further, to measure the self-reported impact from environmental irritants. METHODS: Eighteen steroid-naïve patients with a positive methacholine test underwent capsaicin inhalation provocation on two occasions, before and after regular use of inhaled steroids over at least 3 months. Comparisons were made to 21 healthy controls. Sensitivity to methacholine and levels of exhaled nitric oxide were measured before and after the treatment. The participants also answered a validated questionnaire regarding environmental irritants. RESULTS: The patients displayed higher capsaicin cough sensitivity than the controls before the treatment period, but not afterward. Before treatment, capsaicin cough answer correlated significantly with levels of exhaled nitric oxide, but not with methacholine sensitivity. After treatment with inhaled corticosteroids, the capsaicin cough sensitivity and the inflammatory parameters were normalized. In comparison to the control group, the patients reported more affective reactions to and behavioral disruptions induced by environmental irritants. CONCLUSIONS: In steroid-naïve patients with a positive methacholine test, there is a link between that part of the airway inflammation that is reflected by exhaled nitric oxide and that followed by an augmented reactivity of capsaicin-sensitive sensory nerves. This association disappears after steroid treatment.

A model of quality assessment in patients on long-term oxygen therapy.

BACKGROUND: The difficulty of implementing guidelines for long-term oxygen therapy (LTOT) has been recognized. We performed this analysis to evaluate the impact of a national quality assurance register on the quality of LTOT and to suggest indicators with levels for excellent quality LTOT. METHODS: Based on national register data on Swedish LTOT patients in 1987-2005, we measured nine quality indicators and the achievement levels of the participating counties in fulfilling these treatment criteria. RESULTS: There were improvements in the following eight quality indicators: access to LTOT, PaO(2) < or = 7.3 kPa without oxygen, no current smoking, low number of thoracic deformity patients without concomitant home mechanical ventilation, >16 h of oxygen/day, mobile oxygen equipment, reassessment of hypoxemia when LTOT was not started in a stable state of chronic obstructive pulmonary disease (COPD) and avoidance of continuous oral glucocorticosteroids in COPD. There was decline in the quality indicator PaO(2) > 8 kPa on oxygen. After improvements, three criteria were fulfilled by > or = 80% of the counties in 2004-2005. CONCLUSIONS: We found improvements in eight of nine quality indicators. We suggest these indicators with levels for excellent quality for use in quality assurance of LTOT based on our results.

Increased survival with mechanical ventilation in posttuberculosis patients with the combination of respiratory failure and chest wall deformity.

BACKGROUND: Patients who have had tuberculosis are at risk for respiratory failure with hypercapnea from chest wall deformity and hypoxia from pulmonary sequelae. The combination of hypercapnea and hypoxia justifies both mechanical ventilation and oxygen therapy as treatment options. We aimed to study which treatment mode is associated with the best survival in patients with the combination of respiratory failure and chest wall deformity from tuberculosis. METHODS: Swedish patients starting oxygen therapy or mechanical ventilation between 1996 and 2004 due to the combination of respiratory failure and chest wall deformity from tuberculosis were eligible for conclusion. They were followed up prospectively until October 2006, with death as the primary outcome. RESULTS: A cohort of 188 patients was included. Eighty-five patients received mechanical ventilation, and 103 received oxygen therapy alone. No patients were excluded, and no patients were unavailable for follow-up. Mechanical ventilation was associated with a significantly better survival than oxygen therapy alone, even after adjustments for age, gender, concomitant respiratory disease, blood gas tensions, and vital capacity, with an adjusted hazard risk of death of 0.35 (95% confidence interval, 0.17 to 0.70). CONCLUSION: Patients with the combination of respiratory failure and chest wall deformity from tuberculosis had a significantly better survival when treated with home mechanical ventilation than with long-term oxygen therapy alone. We recommend home mechanical ventilation with or without supplementary oxygen as the first choice of treatment for these patients.

Hospital admission rates among men and women with symptoms of chronic bronchitis and airflow limitation corresponding to the GOLD stages of chronic obstructive pulmonary disease--a population-based study.

UNLABELLED: Chronic obstructive pulmonary disease is a major cause of increased morbidity and mortality. The aim of this study was to investigate hospital admission rates among individuals with symptoms of chronic bronchitis and among those with airflow limitation corresponding to GOLD stages 1-4. METHOD: Between 1974 and 1992, 22044 middle-aged individuals participated in a health screening, which included spirometry (without broncho-dilation), as well as recording of respiratory symptoms and smoking habits. Information on hospital admissions until 31 December 2002 was obtained from local and national registers. The hospital admission rates due to all causes, obstructive lung disease and cardiovascular disease were analysed among individuals with symptoms of chronic bronchitis and among those with airflow limitation corresponding to GOLD stages 1-4 using ordinal regression with adjustment for age and with individuals with normal lung function and without symptoms of chronic bronchitis as reference group. RESULTS: Symptoms of chronic bronchitis and GOLD stages 1-4 showed increased hospital admission rates (hospital admission rates due to obstructive lung disease excluded) among smokers of both genders. Furthermore, symptoms of chronic bronchitis showed increased hospital admission rates due to obstructive lung disease among smoking women. There were also increased hospital admission rates due to obstructive lung disease among smokers of GOLD stages 1-4 and increased hospital admission rates due to cardiovascular disease among female smokers of GOLD stage 2. CONCLUSION: Among smokers, symptoms of chronic bronchitis as well airflow limitation corresponding to GOLD stages 1-4 conveyed a substantial morbidity with increased hospital admission rates due to all causes. The burden of disease is most likely underestimated among individuals with symptoms of chronic bronchitis and chronic obstructive pulmonary disease.