Table 2

Characteristics and clinical outcomes in healthy children by nasal microbiota profiles at age 2 months

CharacteristicNasal microbiota profile at age 2 monthsP value
Moraxella dominant, n=255 (30.4%) Streptococcus dominant, n=188 (22.4%) Dolosigranulum dominant, n=188 (22.4%) Staphylococcus dominant, n=150 (17.9%) Corynebacteriaceae dominant, n=58 (6.9%)
Age at 2 months scheduled visit, months, median (IQR)2.6 (2.4–2.7)2.5 (2.4–2.7)2.6 (2.4–2.7)2.5 (2.3–2.7)2.7 (2.4, 2.8)0.07
Male sex135 (52.9)101 (53.7)105 (55.9)78 (52.0)24 (41.4)0.43
Household sibling188 (73.7)53 (28.2)66 (35.1)34 (22.7)9 (15.5)<0.001
Maternal asthma20 (7.8)16 (8.5)14 (7.4)8 (5.3)6 (10.3)0.71
Parental asthma31 (12.2)31 (16.5)23 (12.2)15 (10.0)9 (15.5)0.44
Maternal smoking during pregnancy9 (3.5)10 (5.3)15 (8.0)7 (4.7)5 (8.6)0.22
Birth by Caesarean section21 (8.2)28 (14.9)22 (11.7)31 (20.7)9 (15.5)0.008
Prematurity (<37 weeks)6 (2.4)9 (4.8)6 (3.2)8 (5.3)5 (8.6)0.16
Small for gestational age4 (1.6)2 (1.1)5 (2.7)3 (2.0)2 (3.4)0.60
Intrapartum antibiotics27 (10.6)25 (13.3)28 (14.9)19 (12.7)6 (10.3)0.70
Breast feeding during the first 2 months of life*170 (66.7)129 (68.6)128 (68.1)103 (68.7)41 (70.7)0.68
Systemic antibiotic use before age 2 months nasal sampling40 (15.7)42 (22.3)24 (12.8)30 (20.0)5 (8.6)0.03
Age 2 month scheduled visit
 Mild respiratory symptoms72 (28.2)22 (11.7)22 (11.7)13 (8.7)6 (10.3)<0.001
 Respiratory virus in nasal sample†61 (23.9)23 (12.2)35 (18.6)8 (5.3)7 (12.1)<0.001
 Age at the end of the follow-up, months, median (IQR)24.0 (16.3–24.0)24.0 (20.2–24.0)24.0 (19.3–
24.0)
23.9 (16.5–
24.0)
23.2 (14.6–24.0)0.08
Clinical outcomes during age 2–24 months‡
 Total number of all ARIs2675171416191339463
 Total number of LRTIs1125552597
 Total duration of follow-up, children years358.7262.7259.2211.882.5
ARIs, incidence rate/100 children years (95% CI)
 All ARIs738 (696–782)643 (599–690)615 (573–660)628 (580–680)552 (485–628)<0.001
 Days with ARI symptoms5991 (5406–6662)4947 (4378–5618)4540 (4027–5142)4584 (4009–5274)3180 (2578–3980)0.002
 LRTIs32 (23–44)21 (14–33)19 (13–29)28 (18–44)8 (3–20)0.007
 Recurrent wheezing§33 (12.9)15 (8.0)22 (11.7)17 (11.3)5 (8.6)0.60
  • Data are number (%) of children unless otherwise indicated. Percentages may not equal 100 because of missingness.

  • *Data on breast feeding available for 653 children.

  • †Rhinovirus was detected in 120 (14.3%) children, respiratory syncytial virus in 11 (1.3%) and other virus in 5 (0.6%) children.

  • ‡Data on ARIs during age 2–24 months available for 798 children. Incidence rates were calculated using negative binomial distribution and log link with natural logarithm of follow-up time from age 2 months visit to age 24 months as an offset.

  • §≥3 wheezing episodes at age 2–24 months.

  • ARI, acute respiratory infection;LRTI, lower respiratory tract infection.