Factors associated with the development of allergic
diseases and atopic march
Factors related to the development of allergic diseases are demonstrated
in Table 2 to Table 4. First of all, high family income significantly
increased risk of AD with adjusted hazard ratio (aHR) of 3.71 (95%CI,
1.31- 10.45; p= 0.013 ). Pet ownership, interestingly, lowered the
risk of AD, aHR = 0.29 (95%CI, 0.12-0.71; p= 0.006 ). Maternal
history of atopic diseases significantly increased the risk of FA with
HR of 3.39 (95%CI, 1.34-8.62; p= 0.01 ), while paternal atopy,
parental atopy, or sibling(s) with atopy did not increase risk of any
allergic diseases. Receiving antibiotics before six months of age
substantially higher the risk of FA, aHR = 3.63 (95%CI, 1.49=8.88;p= 0.005 . Surprisingly, exclusive breastfeeding for 4 to 6 months
and more than 6 months increased risk of FA with aHR of 2.92 (95%CI,
1.16-7.39; p=0.023 ) and aHR of 16.01 (95%CI, 3.27-78.38;p=0.001 ). In contrast, duration of exclusive breastfeeding less
than 4 months lowered the risk of FA with aHR of 0.22 (95%CI,
0.08-0.60; p=0.003 ).
For subjects with wheezing, only factors associated with ever-wheezing
is demonstrated in Table 4. High family income significantly increased
the risk of having ever-wheezing with the adjusted odds ratio (aOR) of
6.98 (95%CI, 1.69-28.79; p=0.007 ). Living in shophouse lowered
the risk of ever-wheezing with aOR of 0.3 (95%CI, 0.1-0.91;p=0.033 ). Infants who exposed to antibiotics before 24 and 30
months of age significantly increased the risk of ever-wheezing with aOR
of 2.79 (95%CI, 1.54-5.04; p=0.001 ) and 2.38 (95%CI, 1.33-4.27;p=0.004 ). Infants who exposed to antibiotics before 6 months of
age significantly increased the risk of recurrent wheezing with OR of
5.46 (95%CI, 1.58, 18.93 p<0.007 ). More frequent
exposure to antibiotics further increased the risk of ever-wheezing and
recurrent wheezing; aOR of 1.51 (95%CI, 1.21-1.88;p<0.001 ) and OR of 1.8 (95%CI, 1.13, 2.87;p=0.014 ) respectively. Subjects who were having first wheeze
before one year of age were twelve times increasing risk of recurrent
wheezing with OR of 12.3 (95%CI, 2.49-60.5). For rhinitis, antibiotics
exposure between 12 and 18 months of age significantly higher the risk;
aOR of 2.41 (95%CI, 1.01-5.74); p=0.046 ). The most common
indication for antibiotics used at our cohort was respiratory tract
infections. Different mode of delivery, gender, having older siblings,
daycare attendance, regular moisturizer used during infancy period,
smoke exposure, indoor pollution and aeroallergen sensitization did not
significantly increase the risk of allergic manifestations in our
cohort.
For atopic march development, having > 2 atopic
manifestations related to high family income (HR = 10 (95%CI,
1.26-79.34; p=0.029 ), maternal atopy (HR = 3.06 (95%CI,
1.09-8.58; p=0.034 ), having FA (HR = 21.19 (95%CI, 5.71-78.59;p=0.001 ), having AD (HR = 6.17 (95%CI, 2.7-14.13;p<0.001 ), having rhinitis (HR = 3.83 (95%CI,
1.75-8.38; p=0.001 ), and multiple sensitization to aeroallergens
(HR = 5.33 (95%CI, 1.43-19.94; p=0.013 ).