Rhinoconjunctivitis among Adolescents in Kuwait and Associated Risk Factors: A Cross-Sectional Study

Table 1

Characteristics of the total study sample and the analytical study sample.

Variables	Total study sample (n = 3864)	Analytical study sample (n = 3689)^§
Sex, n (%)
Female	2169 (56.1)	2061 (55.9)
Male	1695 (43.9)	1628 (44.1)
Age (years)
Median (5^th, 95^th percentile)	12.0 (11.0, 14.0)	12.0 (11.0, 14.0)
BMI-for-age groups, n (%)
Underweight (<−2 SD)	219 (5.8)	211 (5.8)
Normal (−2 to 1 SD)	1517 (40.1)	1450 (40.1)
Overweight (>1 to 2 SD)	961 (25.3)	916 (25.3)
Obese (>2 SD)	1089 (28.8)	1039 (28.7)
Missing, n	78	73
Mode of birth, n (%)
Vaginal	3106 (81.8)	2979 (81.6)
Cesarean section	692 (18.2)	670 (18.4)
Missing, n	66	40
Breastfeeding ever, n (%)
Yes	2894 (76.3)	2777 (76.3)
Missing, n	72	49
Cat exposure in infancy, n (%)
Yes	232 (6.1)	227 (6.2)
Missing, n	35	18
Current cat exposure, n (%)
Yes	500 (13.1)	479 (13.1)
Missing, n	36	20
Dog exposure in infancy, n (%)
Yes	85 (2.2)	82 (2.2)
Missing, n	32	17
Current dog exposure, n (%)
Yes	119 (3.1)	113 (3.1)
Missing, n	28	14
ETS exposure, n (%)
Yes	1755 (45.8)	1682 (45.7)
Missing, n	28	12
Parental history of rhinitis, n (%)
Yes	1736 (46.4)	1700 (46.8)
Missing, n	126	59
Parental history of asthma^†, n (%)
Yes	1238 (32.9)	1207 (33.1)
Missing, n	102	39
Parental history of eczema^‡, n (%)
Yes	904 (24.1)	880 (24.2)
Missing, n	108	46

BMI: body mass index; SD: standard deviation; ETS: Environmental tobacco smoke. ^§Sample of participants with complete information regarding rhinoconjunctivitis (i.e., excluding 175 subjects with incomplete information regarding rhinoconjunctivitis). Maternal and/or paternal history of doctor-diagnosed rhinitis. ^†Maternal and/or paternal history of doctor-diagnosed asthma. ^‡Maternal and/or paternal history of doctor-diagnosed eczema.