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. 2013 Sep 26;69(10):910–917. doi: 10.1136/thoraxjnl-2013-204023

Table 1.

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.