Characteristics of CF and healthy controls infants with paired lung function at 3 months and 1 year
| CF (n=72) | Controls (n=44) | Δ (95% CI) CF– controls | |
|---|---|---|---|
| Male, n (%) | 34 (47) | 21 (48) | −1% (−19 to 18) |
| Gestational age, weeks | 39.1 (1.4) | 40.3 (1.1) | −1.1 (−1.6 to −0.6) |
| Birth weight, z-score* | −0.64 (0.84) | 0.12 (0.81) | −0.76 (−1.07 to −0.45) |
| Birth weight below 10th percentile*, n (%) | 13 (18) | 2 (5) | 14% (1 to 24) |
| White mother, n (%) | 61 (85) | 38 (86) | −2% (−14 to 13) |
| Maternal smoking during pregnancy, n (%) | 8 (11) | 3 (7) | 4% (−8 to 15) |
| Current maternal smoking†, n (%) | 9 (13) | 5 (11) | 1% (−13 to 13) |
| Maternal asthma, n (%) | 14 (19) | 8 (18) | 1% (−14 to 15) |
| Cystic fibrosis infants only | |||
| Age at diagnosis, postnatal age (weeks) | 3.9 (1.7) | ||
| CFTR genotype (classes I–III)‡ | 59 (82%) | ||
| Presented with meconium ileus | 7 (10%) | ||
| Pancreatic sufficient | 5 (7%) | ||
| Respiratory symptoms ever prior to 1 year PFTs | |||
| Wheeze, physician diagnosed | 24 (33%) | ||
| Crackles, physician diagnosed | 6 (8%) | ||
| Cough within 3 weeks of 1-year PFT | 15 (21%) | ||
| Bacterial growth on cough swab, ever§ prior to1 year PFTs | |||
| Pseudomonas aeruginosa, PsA¶ | 25 (35%) | ||
| Other significant bacterial growth** | 17 (24%) | ||
| No growth†† | 30 (42%) | ||
| Additional treatment‡‡ prior to 1 year PFTs | |||
| rhDNase | 6 (8%) | ||
| Intravenous antibiotics, number of courses | 0 (0; 3)§§ | ||
| GERD treatment | 38 (53%) | ||
Data shown as mean (SD) for continuous and n (%) for categorical variables unless otherwise stated.
*Calculated according to Cole et al.13
†Objectively validated by the analysis of cotinine levels.23
‡10% were classes IV–V and 8% unknown (or not classified).
§Swabs collected routinely in clinic at least every 2 months, prior to PFT and also when symptomatic.
¶Definition of colonisation according to Lee et al.24 Only 1 infant had chronic PsA.
**Significant bacterial infection with no previous PsA ever included 12 (17%) with methicillin-sensitive Staphylococcus Aureus, 14 (19%) with Haemophilus Influenzae, 3 (4%) with Stenotrophomonas maltophilia, 2 (3%) with Achromobacter xylosidans, 3 (4%) with methicillin-resistant Staphylococcus Aureus and 2 (3%) with Aspergillus fumigatus.
††Included those with no growth, upper respiratory tract flora or isolated E Coli only.
‡‡In addition to the prophylactic flucloxacillin prescribed for all CF NBS infants from diagnosis.
§§Median (range).
Δ, mean difference between groups; CF, cystic fibrosis; GERD, Gastro-oesophageal reflux disease, n, number; NBS, newborn screened; PFT, pulmonary function test.