Possible risk factors for poor asthma control assessed in a cross-sectional population-based study from Telemark, Norway

Abstract

This cross-sectional study of the general population of Telemark County, Norway, aimed to identify risk factors associated with poor asthma control as defined by the Asthma Control Test (ACT), and to determine the proportions of patients with poorly controlled asthma who had undergone spirometry, used asthma medication, or been examined by a pulmonary physician. In 2014-2015, the study recruited 326 subjects aged 16-50 years who had selfreported physician-diagnosed asthma and presence of respiratory symptoms during the previous 12 months. The clinical outcome measures were body mass index (BMI), forced vital capacity (FVC) and forced expiratory volume in one second (FEV 1), fractional exhaled nitric oxide (FeNO), immunoglobulin E (IgE) in serum and serum C-reactive protein (CRP). An ACT score � 19 was defined as poorly controlled asthma. Overall, 113 subjects (35%) reported poor asthma control. The odds ratios (ORs) and 95% confidence intervals (CIs) for factors associated with poorly controlled asthma were: self-reported occupational exposure to vapor, gas, dust, or fumes during the previous 12 months (OR 2.0; 95% CI 1.1-3.6), body mass index � 30 kg/m 2 (OR 2.2; 95% CI 1.2-4.1), female sex (OR 2.6; 95% CI 1.5-4.7), current smoking (OR 2.8; 95% CI 1.5-5.3), and past smoking (OR 2.3; 95% CI 1.3-4.0). Poor asthma control was also associated with reduced FEV 1 after bronchodilation (β-3.6; 95% CI-7.0 to-0.2). Moreover, 13% of the participants with poor asthma control reported no use of asthma medication, 51% had not been assessed by a pulmonary physician, and 20% had never undergone spirometry. Because these data are cross-sectional, further studies assessing possible risk factors in general and objectively measured occupational exposure in particular are needed. However, our results suggest that there is room for improvement with regards to use of spirometry and pulmonary physician referrals when a patient's asthma is inadequately controlled.

Obesity, Inflammation, and Severe Asthma: an Update

“…The links between obesity and asthma are complex and perhaps best considered to be bi-directional [24]. Poorer asthma control and quality of life, increased corticosteroid use, and emergency service attendance in this patient cohort have been demonstrated in numerous studies worldwide [7,19,20,26,27,31].…”

“…The association between obesity and asthma has historically been considered uni-directional; people with severe asthma become less active and deconditioned, weight increases, and increased usage of oral corticosteroids (OCS) further aggravates the weight gain cycle. Whilst this cohort of patients undeniably exists, increasing evidence supports the causal link between raised BMI, asthma, and poor asthma control (Table 1 [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37]). Cluster cohort studies show a now widely recognised female-predominant obese severe asthma phenotype [38][39][40], particularly affecting peri-and post-menopausal women [37].…”

Asthma control and its predictors in Ethiopia: Systematic review and meta-analysis

“…Price et al reported more than 40% of asthma patients used their reliever medications three or more times in the previous week, which the author may judge the reason for the high levels of uncontrolled asthma [ 34 ]. Several studies also reported patients with severe asthma [ 12 , 61 – 63 ], history of asthma exacerbations/hospitalizations [ 45 , 49 , 53 , 61 , 63 , 64 ], who had comorbid diseases [ 13 , 50 – 52 , 65 ], smoking [ 43 , 52 , 66 ], oral corticosteroid use [ 12 , 63 ], and irregular follow-up visit [ 56 , 67 ] were more likely had a higher rate of uncontrolled asthma.…”

Residential Exposure to Dampness Is Related to Reduced Level of Asthma Control among Adults

“…There is some previous epidemiological evidence on the determinants of asthma control measured by applying the ACT score. Abrahamsen and colleagues characterized the risk factors for poor asthma control in a cross-sectional study of the general population of Telemark County, Norway [ 5 ]. They used an ACT score ≤ 19 as the measure of poor asthma control.…”

“…However, there is substantial epidemiological evidence showing that indoor dampness and mold problems increase the risk of asthma [ 1 , 2 , 3 ]. Furthermore, there is accumulating evidence that some environmental exposures, such as ambient air pollution and chemical exposures from cleaning agents, increase the risk of poor asthma control [ 5 , 6 , 7 , 8 ]. Based on the literature review, we hypothesized that exposure to microbial agents or chemicals from damp structures in residential buildings influences the level of asthma control.…”