Measurement of disability and breathlessness in asthma is important to guide treatment. Using an incentive spirometer, Triflo II (Tyco Healthcare, Mansfield, MA, USA), we developed a three-minute respiratory exercise test (3-MRET) to score the maximal breathing capacity (MBC) and perception of dyspnea (POD) index by means of repetitive inspiratory efforts achieved within 3 minutes. POD index was calculated based on the ratio of breathlessness on visual analogue scale over MBC score. In 175 normal healthy subjects and 158 asthmatic patients of mild (n = 26), moderate (n = 78), and severe (n = 54), severity, the mean (95% CI) MBC scores in mild, moderate, and severe asthma patients were 168 (145-192), 153 (136-169), and 125 (109-142) respectively, and 202 (191-214) in normal subjects (p < 0.001). The mean POD index in mild, moderate, and severe asthma patients was 16 (9-23), 25 (14-37), and 57 (14-100), respectively, and 6 (4-7) in normal subjects (p < 0.001). Intraclass correlation coefficients for MBC score and POD index in 17 asthmatic and 20 normal subjects were high. In 14 asthmatic patients randomized to receiving nebulized beta2-agonist or saline in a cross-over, double-blind study, % forced expiratory volume in one second (FEV1) change correlated with % change in MBC score [r(s) = 0.49, p < 0.01] and POD index [r(s)-0.46, p = 0.012]. In 21 asthmatic and 26 normal subjects, the MBC score and POD index correlated with the walking distance and walking POD index of the six-minute walking test (6MWT). We conclude that 3MRET is discriminative between asthmatic patients of varying severity and normal subjects, is reproducible, is responsive to bronchodilator effect, and is comparable with 6MWT. Taken together, it has the potential to score disability and POD in asthma simply and effectively.
Matched MeSH terms: Adrenergic beta-Agonists/therapeutic use
OBJECTIVE: Use of oral short-acting beta 2-agonist (SABA) persists in non-resource poor countries despite concerns for its lower efficacy and safety. Utilisation and reasons for such use is needed to support the effort to discourage the use of oral SABA in asthma. This study examined the frequency of oral short-acting Beta 2-agonist (SABA) usage in the management of asthma in primary care and determined correlates of its usage.
METHODS: Data used were from the 2014 National Medical Care Survey in Malaysia, a nationally representative survey of primary care encounters (weighted n = 325818). Using methods of analysis of data for complex surveys, we determined the frequency of asthma diagnosis in primary care and the rate of asthma medication prescription, which includes oral SABA. Multivariate logistic regression models were built to assess associations with the prescription of oral SABA.
RESULTS: A weighted estimate of 9241 encounters presented to primary care with asthma in 2014. The mean age of the patients was 39.1 years. The rate of oral SABA, oral steroids, inhaled SABA and inhaled corticosteroids prescriptions were 33, 33, 50 and 23 per 100 asthma encounters, respectively. It was most commonly used in patients with the age ranged between 20 to less than 40 years. Logistic regression models showed that there was a higher odds of oral SABA usage in the presence of respiratory infection, prescription of oral corticosteroids and in the private sector.
CONCLUSION: Oral SABA use in asthma is found to be common in a non- resource poor setting and its use could be attributed to a preference for oral medicines along undesirable clinical practices within a fragmented health system.