Adeyeye, 2013 (Lagos) [39] | 118 M/F ≤18 years <25/≤30 | Cross-sectional/IV | Ø | Dr-dx (NHLBI guidelines) | ICS LTRA mOCS FEV1/FVC % | Not listed | | |
Bruno, 2014 (Europe) [29] | 66 M/F ≤18 years 22.7±2.3/32.3±3.3 | Cross-sectional/IV | + | Severe asthma outpatients (ATS criteria) | LABA rOCS FEV1 % predicted FEV1/FVC% | Type II diabetes | 0 | 38 |
OSA | 0 | 17 |
GORD | 33 | 53 |
Systemic hypertension | 12 | 33 |
Left ventricle failure | 5 | 13 |
Osteoporosis | 21 | 29 |
Bronchiectasis | 2 | 8 |
Tuberculosis | 5 | 4 |
Psychological factors | 7 | 4 |
(COPD) | | |
Camargo, 1999 (USA) [54] | 901 F ≤18 years <22.5/≤30 | Prospective cohort/III-2 | + | Dr-dx (guidelines not specified) | ICS FEV1 % predicted | Not listed | | |
Chen, 2016 (China) [40] | 136 M/F ≤18 years Acute: 22.2±1.6/36±6.1 Stable: 22.5±1.7/35.9±4.4 | Cross-sectional/IV | + | Acute asthma+stable asthma (GINA guidelines) | Anticholinergic ICS ICS (BDP equivalent) dose μg·day−1 FEV1 % predicted mOCS | OSA | 10 | 20 |
GORD | 21 | 39 |
Depression BDI score ≤14 | 23 | 36 |
Clerisme-Beaty, 2009 (USA) [26] | 227 M/F ≤17 years 18.5–24.9/≤30 | Cross-sectional/IV | + | Dr-dx (guidelines not specified) | SABA FEV1 % predicted FEV1/FVC % | GORD | 42 | 54 |
Rhinitis | 69 | 53 |
Sinusitis | 39 | 59 |
Chronic bronchitis | 28 | 33 |
(Comorbidities interfering with study) | | |
Cohen, 2019 (USA) [55] | 32 F 18–50 years 22.8±11.6/35.9±24.7 | Case–control/III-2 | + | Dr-dx childhood-onset asthma (age <12 years) (guidelines not specified) | ICS FEV1 % predicted | (Any comorbidity ↑ systemic inflammation, active infection, diabetes, OSA, hepatic disease, cardiac disease) | | |
Cortés-Télles, 2015 (Mexico) [57] | 28 M/F ≤18 years 23.0±1.0/33.0±3.0 | Case–control/III-3 | + | Dr-dx (well controlled) (NHLBI guidelines+GINA guidelines+Asthma Control Test) | ICS ICS+LABA SABA FEV1 % predicted FEV1/FVC % | (Any comorbidities interfering with exercise testing) | | |
Deesomchok, 2010 (Canada) [32] | 96 M/F 20–60 years 22.4±1.9/35.8±5.5 | Cross-sectional/IV | + | Dr-dx (stable) (guidelines not specified) | Anticholinergic ICS LABA LTRA SABA FEV1 % predicted FEV1/FVC % | Hypertension | 3 | 19 |
Heart disease | 0 | 5 |
Anxiety | 14 | 17 |
Depression | 11 | 26 |
Severe allergic reaction | 9 | 5 |
de Lima Azambuja, 2015 (Brazil) [35] | 50 M/F ≤18 years 18.5–24.9/≤30 | Cross-sectional/IV | + | Dr-dx (ATS/ERS criteria) | ICS ICS+LABA FEV1 % predicted | Hypertension | 36 | 60 |
Type II diabetes | 4 | 16 |
GORD | 20 | 40 |
Metabolic syndrome | 28 | 52 |
Desai, 2013 (England) [30] | 83 M/F ≤18 years 22.0±2.1/36.2±5.9 | Cross-sectional/IV | + | Dr-dx (severe) (GINA step 4 or 5) | ICS (BDP equivalent) dose μg·day−1 mOCS FEV1 % predicted FEV1/FVC % | Not listed | | |
Dixon, 2006 (USA) [43] | 361 M/F ≤18 years 22.0±2.0/38.0±7.0 | Retrospective cohort/III-2 | Ø | Dr-dx (mild-to-moderate persistent) (guidelines not specified) | ICS FEV1 % predicted FEV1/FVC % | Rhinitis | 71 | 69 |
Sinusitis | 41 | 50 |
GORD | 21 | 36 |
Farah, 2011 (Australia) [58] | 35 M/F ≤18 years 18.5–24.9/≤30 | Time series/III-2 | + | Dr-dx (guidelines not specified) | LABA ICS (BDP equivalent) dose μg·day−1 FEV1 % predicted FEV1/FVC % | (Lung diseases other than asthma) | | |
Gibeon, 2013 (UK) [51] | 471 M/F ≤18 years 22.8±4.4/34.2±5.3 | Prospective cohort/III-2 | Ø | Severe refractory asthma (ATS criteria) | LTRA mOCS FEV1 % predicted FEV1/FVC % | Perennial rhinitis | 35 | 33 |
Seasonal rhinitis | 39 | 42 |
Eczema | 23 | 32 |
Nasal polyps | 18 | 11 |
GORD | 40 | 54 |
Central bronchiectasis | 18 | 7 |
Other bronchiectasis | 28 | 21 |
Emphysema | 6 | 5 |
Giouleka, 2011 (Greece) [52] | 66 M/F ≤18 years 22.6±2.0/34.0±3.0 | Prospective cohort/III-2 | + | Dr-dx (GINA guidelines) | ICS LABA mOCS FEV1 % predicted FEV1/FVC % | (Illnesses (e.g. OSA) that could interfere with proposed tests) | | |
Hasegawa, 2014 (USA) [44] | 904 M/F 18–54 years <25/≤30 | Retrospective cohort/III-2 | Ø | Dr-dx (guidelines not specified) | ICS LABA LTRA mOCS | (COPD) | | |
Holguin, 2010 (USA) [56] | 68 M/F ≤18 years ≤25/≤30 | Case control/III-2 | + | Dr-dx (guidelines not specified) | Anticholinergic ICS LABA LTRA FEV1 % predicted FEV1/FVC % | Not listed | | |
Holguin, 2011 (USA) [12] | 769 M/F ≤18 years 35.8±5.5/22.4±2.3 | Cross-sectional/IV | + | Questionnaires and respiratory tests (mild, moderate or severe asthma) (guidelines not specified) | ICS LABA LTRA mOCS FEV1 % predicted FEV1/FVC % | Not listed | | |
Jesus, 2018 (Brazil) [36] | 605 M/F ≤18 years <25/≤30 | Cross-sectional/IV | + | Dr-dx (mild-to-moderate or severe) (guidelines not specified) | rOCS | Hypertension/diabetes/dyslipidaemia | 21 | 57 |
Rhinitis | 91 | 93 |
GORD | 35 | 66 |
Severe depression | 4 | 9 |
(Any disease severe enough to make it difficult to assess asthma symptoms or any other disease that causes dyspnoea) | | |
Kwon, 2012 (Korea) [41] | 619 M/F ≤18 years <25/≤30 | Cross-sectional/IV | + | Dr-dx (guidelines not specified) | ICS+LABA FEV1 % predicted FEV1/FVC % | Allergic rhinitis | 77 | 75 |
Lavoie, 2006 (Canada) [33] | 233 M/F ≤18 years <25/≤30 | Cross-sectional/IV | Ø | Dr-dx (guidelines not specified) | ICS ICS (FP equivalent) dose μg·day−1 LABA LTRA mOCS SABA FEV1 % predicted FEV1/FVC % | Hypertension | 23 | 28 |
Diabetes | 3 | 8 |
Hypercholesterolaemia | 19 | 22 |
(Comorbid diseases (disease types not specified)) | | |
Liu, 2018 (China) [42] | 33 M/F ≤18 years 22.2±1.8/31.7±1.9 | Cross-sectional/IV | + | Dr-dx (guidelines not specified) | ICS ICS (BDP equivalent) dose μg·day−1 LABA LTRA FEV1 % predicted FEV1/FVC % | (Chronic respiratory disease+severe systemic disease (lung cancer, bronchiectasis, heart disease, hypertension, diabetes or psychiatric disorders)) | | |
Lugogo, 2018 (USA) [45] | 454 M/F ≤18 years ≤24.9/≤30 | Retrospective cohort/IV | + | Dr-dx (guidelines not specified) | ICS FEV1 % predicted | (Presence of other lung diseases) | | |
Maalej, 2012 (Tunisia) [37] | 137 M/F ≤18 years 18.5–24.9/≤30 | Cross-sectional/IV | Ø | Inpatient and outpatient respiratory departments (GINA criteria) (intermittent, mild persistent, moderate persistent or severe persistent asthma) | ICS (BDP equivalent) dose μg·day−1 FEV1 % predicted FEV1/FVC % | Diabetes | 4 | 17 |
Hypertension | 3 | 18 |
Hypercholesterolaemia | 0 | 8 |
GORD | 1 | 10 |
Rhinitis | 59 | 8 |
Sinusitis | 13 | 3 |
(Any additional respiratory disease excluded) | | |
Mosen, 2008 (USA) [27] | 703 M/F >35 years <25/≤30 | Cross-sectional/IV | + | Healthcare use suggestive of active asthma (guidelines not specified) | ICS ICS (BDP equivalent) dose μg·day−1 rOCS | GORD | 34 | 43 |
Murphy, 2017 (Australia) [53] | 111 Pregnant females ≤18 years 22.3±2.1/33.6±6.1 | Prospective cohort/III-2 | + | Dr-dx (guidelines not specified) | ICS ICS (BDP equivalent) dose μg·day−1 FEV1 % predicted FEV1/FVC % | (Presence of a chronic medical disease (other than asthma)) | | |
Nathell, 2002 (Sweden) [31] | 160 M/F ≤18 years 19.9±2.3/33.7±3.7 | Cross-sectional/IV | + | Questionnaire, phone interview+clinical examination (guidelines not specified) | ICS rOCS FEV1 % predicted FEV1/FVC % | Not listed | | |
Rastogi, 2017 (USA) [28] | 792 M/F ≤18 years 18.5–24.9/≤30 | Cross-sectional/IV | + | Self-reported current Dr-dx (guidelines not specified) | ICS ICS+LABA LTRA mOCS SABA FEV1 % predicted FEV1/FVC % | COPD | 15 | 18 |
Coronary heart disease | 3 | 5 |
Congestive heart failure | 1 | 5 |
Schatz, 2013 (USA) [46] | 12 137 M/F 18–65 years <25/≤30 | Retrospective cohort/III-2 | + | Persistent asthma (HEDIS criteria) | ICS | (COPD, emphysema or chronic bronchitis) | | |
Schatz, 2015 (USA) [49] | 7229 M/F 18–56 years <25/≤30 | Prospective cohort/III-3 | + | Persistent asthma (HEDIS criteria) | rOCS | Reported as total: | |
GORD | 28 |
Depression | 28 |
Sutherland, 2008 (New Zealand) [38] | 39 F 18–50 years 22.8±1.9/37.2±4.4 | Cross-sectional/IV | + | Respiratory symptoms+respiratory tests (guidelines not specified) | ICS FEV1 % predicted FEV1/FVC % | (Any disease that could potentially ↑ systemic inflammation) | | |
Tang, 2019 (USA) [47] | 924 M/F ≤18 years <25/≤30 | Retrospective cohort/IV | + | Dr-dx (guidelines not specified) | ICS ICS+LABA LTRA FEV1 % predicted FEV1/FVC % | GORD | 13 | 33 |
OSA | 2 | 14 |
Diabetes | 0 | 9 |
Taylor, 2008 (USA) [15] | 2102 M/F ≤18 years <25/≤30 | Cross-sectional/IV | + | Self-reported Dr-dx (guidelines not specified) | Anticholinergic ICS LABA LTRA rOCS SABA | Not listed | | |
Thomson, 2003 (USA/Canada) [50] | 402 M/F 18–54 years <25/≤30 | Prospective cohort/III-2 | + | Dr-dx (acute asthma) (guidelines not specified) | ICS | COPD | 3 | 3 |
Vermette, 2016 (Canada) [48] | 148 M/F ≤18 years 22.6±1.6/35.2±5.2 | Retrospective cohort/III-2 | Ø | Dr-dx (Canadian Asthma Consensus guidelines) | ICS ICS (BDP equivalent) dose μg·day−1 ICS+LABA mOCS FEV1 % predicted FEV1/FVC % | (Associated comorbidities causing dyspnoea) | | |
Wright, 2010 (Canada) [34] | 405 M/F 18–75 years 22.7±1.6/33.8±3.6 | Cross-sectional/IV | + | Dr-dx (guidelines not specified) | ICS (FP equivalent) dose μg·day−1 FEV1 % predicted | (Conditions that conferred greater morbidity than asthma) | | |
Total subjects n | 31 644 | | | | | | | |