eTable 1.
Studies Using Unsupervised Data-Driven Methods to Study Wheeze Trajectories
| Study | Study population | Wheeze data collection time points | Wheeze trajectories | Key findings |
|---|---|---|---|---|
| Oksel et al,1 2019 | STELAR consortium of 5 birth cohorts | • Infancy: 0.5-1 y • Early childhood: 2-3 y • Preschool or early school age: 4-5 y • Middle childhood: 8-10 y • Adolescence: 14-18 y |
• Never or infrequent wheeze • Early-onset preschool remitting wheeze • Early-onset mid-childhood remitting wheeze • Persistent wheeze • Late-onset wheeze |
• All trajectories were associated with higher risks of asthma development and poorer lung function • Persistent trajectory was linked to the highest risk of asthma |
| Duijts et al,2 2016 | ALSPAC cohort | • 6, 18, 30, 42, 54, 69 and 81 mo | • Never or infrequent wheeze • Transient early wheeze • Prolonged early wheeze • Intermediate-onset wheeze • Late-onset wheeze • Persistent wheeze |
• All trajectories were associated with higher risks of asthma development. • Intermediate-onset and persistent wheeze were linked to the highest risk of asthma and poor lung function. |
| Henderson et al,3 2008 | ALSPAC cohort | • 6, 18, 30, 42, 54, 69 and 81 mo | • Never or infrequent wheeze • Transient early wheeze • Prolonged early wheeze • Intermediate-onset wheeze • Late-onset wheeze • Persistent wheeze |
• Intermediate-onset, late-onset, and persistent wheeze were linked to a higher risk of any skin prick sensitivity. • Maternal history of asthma and allergy increased the risk of developing all trajectories (highest risk for persistent wheeze). |
| Savenije et al,4 2011 Caudri et al,5 2013 |
ALSPAC and PIAMA cohorts | • ALSPAC: 6, 18, 30, 42, 54, 69, 81, and 91 mo • PIAMA: 3, 12, 24, 36, 48, 60, 72, 84, and 96 mo |
ALSPAC: • Never or infrequent wheeze • Transient early wheeze • Prolonged early wheeze • Intermediate-onset wheeze • Late-onset wheeze • Persistent wheeze PIAMA • Never or infrequent • Transient early wheeze • Intermediate-onset wheeze • Late-onset wheeze • Persistent wheeze |
PIAMA • Intermediate-onset and persistent wheeze were linked to the highest risk of asthma and poorer lung function. • Intermediate-onset wheeze was associated with the highest risk of allergic sensitization at 4 and 8 y. • Consistent with results from ALSPAC. • Male sex, parental allergy, young maternal age, higher maternal BMI, low gestational age, smoke exposure during pregnancy, having older siblings, and childcare attendance increased the risk of transient early wheeze. • Male sex, parental allergy, and low breastfeeding increased the risk of persistent wheeze. • Low birthweight increased the risk of intermediate-onset wheeze. • Maternal allergy increased the risk of late-onset wheeze. |
| Yang et al,6 2018 | Hospital-based birth cohort in Tokyo |
• Every year from 1 to 9 y | • Never or infrequent wheeze • Transient early wheeze • School-age onset wheeze • Early-childhood onset remitting wheeze • Persistent wheeze |
• Persistent wheeze had the highest proportion of children with a family history of allergy. • Smoke exposure during infancy was linked to a higher risk of transient early and persistent wheeze. |
| Kotecha et al,7 2019 | Millennium Cohort Study | • 9 months and at 3, 5, 7, and 11 y | • Never or infrequent wheeze • Early wheeze • Persistent wheeze • Late wheeze |
• Formal childcare was associated with early wheeze development. • Maternal atopy increased the risk of developing all trajectories, especially for persistent wheeze. |
| Belgrave et al,8 2013 | MAAS | • 1, 3, 5, and 8 y | • No wheezing • Transient early wheeze • Late-onset wheeze • Persistent controlled wheeze • Persistent troublesome wheeze |
• Children with persistent troublesome wheeze were the most vulnerable to hospitalizations, poor lung functions, and airway hyperreactivity. |
| Cano-Garcinuño et al,9 2014 | SLAM | • 12 three-month periods between 0 and 36 mo | • Never or infrequent wheeze • Transient wheeze • Persistent wheeze • Late wheeze |
• All 3 wheeze phenotypes were linked to a higher occurrence of active asthma at 6 y. |
| Chen et al,10 2012 | CCCEH | • In-person interview: 6, 12, 24, 36, 60, 84, and 108 mo • Telephone interview: 3, 9, 15, 18, 21, 30, 48, and 72 mo |
• Never or infrequent wheeze • Early transient wheeze • Early persistent wheeze • Late-onset wheeze |
• Maternal asthma increased the risk of all phenotypes as compared with never/infrequent. • Male children had a higher risk of early persistent wheeze. • Early persistent wheeze was more common during cold/flu season. |
| Lodge et al,11 2014 | MACS (high-risk children) | • Every 4 wk from birth to age 15 mo, once at age 18 mo, and yearly at age 2-7 y (23 time points) | • Never or infrequent wheeze • Early transient wheeze • Early persistent wheeze • Intermediate-onset wheeze • Late-onset wheeze |
• LRTI and childcare attendance in the first year of life and low breastfeeding were risk factors for early transient wheeze. • Aeroallergen sensitization was a risk factor for early persistent wheeze. • LRTI, eczema, aeroallergen, and food sensitization were risk factors for intermediate-onset wheeze whereas exposure to dogs and having no older siblings were protective. • High exposure to parental smoke at birth and low breastfeeding were risk factors for late-onset wheeze. |
| Tse et al,12 2016 | Project Viva | • Yearly from 1 to 9 y | • Never or infrequent wheeze • Early transient wheeze • Persistent wheeze |
• Maternal asthma, early bronchiolitis, and eczema increased the risk of persistent wheeze. |
| Depner et al,13 2014 | PASTURE | • 2, 12, 18, 24, 36, 48, 60, and 72 mo | • No or infrequent wheeze • Transient wheeze • Intermediate wheeze • Late-onset wheeze • Persistent wheeze |
• Persistent wheeze was linked to asthma locus on chromosome 17q21. • Late-onset wheeze was linked to atopic sensitization at 6 y. |
Abbreviations: ALSPAC, Avon Longitudinal Study of Parents and Children; BMI, body mass index; CCCEH, Columbia Center for Children's Environmental Health birth cohort study; LRTI, Lower respiratory tract infection; MACS, Melbourne Atopy Cohort Study; MAAS, Manchester Asthma and Allergy Study; PASTURE, Protection against Allergy–Study in Rural Environments; PIAMA, Prevention and Incidence of Asthma and Mite Allergy; SLAM, Sibilancias de Lactante y Asma de Mayor; STELAR, Study Team for Early Life Asthma Research.