Table 2

Univariable and multivariable logistic regression analysis of variables associated with positive Aspergillus BAL cultures at age 5 years

Univariable logistic regression∆OFVOR (95% CI)
Categorical variable
 Female−1.770.57 (0.06 to 1.48)
 Meconium ileus−0.411.37 (0.48 to 5.81)
 Children in BAL arm of ACFBAL study−0.881.07 (0.47 to 2.41)
 Received gentamicin−0.011.06 (0.25 to 3.13)
 Received anti-staphylococcal prophylaxis until their first birthday−2.530.48 (0.30 to 5.32)
Continuous variables
 Body mass index z-score at BAL−0.650.89 (0.44 to 1.59)
 Cumulative dosage of intravenous tobramycin received (mg)*−9.191.08 (0.99 to 1.10)
 Cumulative dosage of inhaled tobramycin received (mg)*−2.881.00 (0.99 to 1.01)
 Cumulative dosage of intravenous tobramycin (not associated with eradication therapy) (mg)−3.421.12 (1.00 to 1.12)
 Cumulative dosage of intravenous and oral antibiotics (not associated with eradication therapy) (mg)†−0.771.00 (1.00,1.00)
 Minimum annual temperature at geographic region at baseline (°C)−2.070.96 (0.83 to 0.99)
 Maximum annual temperature at geographic region at baseline (°C)−3.891.09 (1.01 to 1.17)
 Discrete variables
 Number of Pseudomonas aeruginosa eradication therapy courses received before BAL‡−14.551.61 (1.23 to 2.12)
 Number of ‘all-cause’ CF-related hospitalisations before age 5 years BAL−3.941.11 (0.78 to 1.24)
 Number of pulmonary exacerbations requiring hospitalisation before age
 5 years BAL
−0.061.00 (0.86 to 1.06)
 Number of all pulmonary exacerbations before age 5 years BAL−0.660.92 (0.9 to 1.07)
Multivariable logistic regression
Base model+number of P. aeruginosa eradication therapy courses received before BAL positive cultures for Aspergillus ∆OFV OR (95% CI)
 Cumulative dosage of intravenous tobramycin received (mg)−0.43§1.02 (0.95 to 1.09)
 Number of ‘all-cause’ CF-related hospitalisations before age 5 years BAL−0.03§1.01 (0.98 to 1.02)
 Cumulative dosage of intravenous tobramycin (not associated with eradication therapy) (mg)−0.10§1.01 (1.00 to 1.01)
 Maximum annual temperature of geographic location at baseline (°C)−4.56§1.11 (1.01 to 1.20)¶
Final model
 Base model+number of P. aer uginosa eradication therapy courses received before age 5 years BAL−14.55 1.61 (1.23 to 2.12)**
  • *Combined with an anti-pseudomonal beta-lactam antibiotic.

  • †Antibiotics other than tobramycin and not associated with eradication therapy (eg, intravenous cefuroxime, oral macrolides, amoxicillin-clavulanate and co-trimoxazole).

  • ‡Model carried forward from the univariable step to the multivariable step.

  • §Based on (Base+number of P. aeruginosa eradication therapy courses received before BAL).

  • ¶Excluded from the final model during backward elimination step as p>0.01.

  • **Bootstrap results (95% CI).

  • ACFBAL, Australasian Cystic Fibrosis Bronchoalveolar Lavage study; BAL, bronchoalveolar lavage; CF, cystic fibrosis; ∆OFV, change in objective function value.