Table 2. Summary of major clinical trials on the effects of controlling comorbidity on asthma outcomes in adults.
First author (year)ref | Participants | Study design and intervention | Main findings on the intervention |
---|---|---|---|
Dixon (2014)80 | 237 adults and 151 children with chronic sinonasal disease and inadequately controlled asthma (median age 27 years old) | 24-week randomized double-blind placebo-controlled trial, intranasal mometasone versus placebo | In adults, there was a small difference in asthma symptoms and in nasal symptoms, but no difference in asthma quality of life, lung function, or episodes of poorly controlled asthma. |
Gevaert (2012)82 | 24 patients with nasal polyps and asthma (median age around 50 years old) | 16-week randomized double-blind placebo-controlled trial, omalizumab versus placebo | There was a significant decrease in endoscopic polyp scores and Lund-Mackay score, and also in upper and lower airway symptoms and quality of life scores. |
Stenius-Aarniala (2000)83 | 38 patients with asthma and obesity (BMI 30-42 kg/m2, age 18-60 years old) | 1-year randomized open-labelled controlled trial, supervised weight reduction program with 8-week very low energy diet versus standard care | There were significant reduction in body weight (14.5%) and also improvements in lung function parameters (FEV1 and FVC), dyspnea scale, rescue medication use, and exacerbation frequency. |
Dias-Júnior (2014)84 | 33 patients with severe asthma and obesity (mean BMI 39 kg/m2, mean age 42 years old) | 6-month randomized open-labelled controlled trial, weight loss program (low caloric intake, sibutramine 10 mg per day, and orlistat maximum 120 mg per day) versus standard care | There were significant reduction in body weight (7.5%) and also improvements in asthma control and FVC. |
Chaudhuri (2006)85 | 32 smokers with asthma (mean age 47 years old, 36 pack-year) | 6-week, non-randomized open controlled trial, smoking cessation | There were significant improvement in FEV1 and reduction in sputum neutrophils. |
Tønnesen (2005)86 | 220 smokers with asthma (mean age 35 years old, 19 pack-year) | 4-month, randomized open controlled trial, complete smoking cessation versus smoking reduction to fewer than seven cigarettes/day versus continuation of usual smoking | There were significant improvements in asthma-specific quality of life score, reductions in self-reported day and night use of rescue β2-agonists, doses of inhaled corticosteroids, in daytime asthma symptoms, and in bronchial hyperreactivity. |
BMI, body mass index; FEV1, forced expiratory volume in 1 second; FVC, forced vital capacity.