Table 2

Risk factors for allergen skin test reactivity

Risk factorTotal n=3.821Skin test reactivity n=477Univariate OR (95% CI)Multivariate OR (95% CI)p Value
Sex
 Female1855189 (10.2%)1.0
 Male1966288 (14.6%)1.48 (1.21 to 1.81)
Age, years
 6–91491130 (8.7%)1.0*
 10–121340186 (13.9%)1.76 (1.38 to 2.24)
 13–16990161 (16.3%)2.06 (1.60 to 2.66)
Gas for cooking (3)
 No22039 (17.7%)1.01.0
 Yes3598438 (12.2%)0.69 (0.47 to 1.02)0.70 (0.47 to 1.04)0.075
Consumption of river water
 No109493 (8.5%)1.01.0
 Yes2727384 (14.1%)1.40 (1.02 to 1.93)1.40 (1.01 to 1.95)0.043
Birth order (1)
 1st–3rd2087236 (11.3%)1.01.0
 ≥4th1733241 (13.9%)1.24 (1.02 to 1.51)1.20 (0.97 to 1.48)0.090
Attending day care (117)
 No1973262 (13.3%)1.01.0
 <1 year old46245 (9.7%)0.67 (0.46 to 0.97)0.72 (0.50 to 1.05)
 ≥1 year old1269154 (12.1%)0.80 (0.64 to 1.01)0.85 (0.67 to 1.07)0.164
Contact with animals in farms at least once a week (5)
 No2625290 (11.0%)1.01.0
 Yes1191186 (15.6%)1.38 (1.11 to 1.72)1.27 (1.01 to 1.59)0.042
Mother smoked in pregnancy (66)
 No3305397 (12.0%)1.01.0
 Yes45074 (16.4%)1.35 (1.02 to 1.80)1.24 (0.92 to 1.68)0.163
Any helminth infection (103)
 No932160 (17.2%)1.01.0
 Yes2786309 (11.1%)0.69 (0.54 to 0.87)0.69 (0.54 to 0.87)0.002
A lumbricoides infection (103)
 No1724247 (14.1%)1.01.0
 Yes1971222 (11.3%)0.84 (0.68 to 1.05)0.96 (0.76 to 1.20)0.713
T trichiura infection (103)
 No1590265 (16.7%)1.01.0
 Yes2128204 (9.6%)0.64 (0.51 to 0.80)0.64 (0.50 to 0.81)<0.001
Intensity of A lumbricoides infection, median (103)
 Negative2135307 (14.4)1.0*1.0
 ≤4620 epg79182 (10.4%)0.78 (0.59 to 1.03)0.82 (0.61 to 1.09)
 >4620 epg79280 (10.1%)0.68 (0.51 to 0.91)0.81 (0.60 to 1.10)0.237
Intensity of T trichiura infection, median (103)
 Negative1759290 (16.5%)1.0*1.0
 ≤490 epg1030112 (10.9%)0.70 (0.54 to 0.89)0.68 (0.52 to 0.88)
 >490 epg92967 (7.2%)0.47 (0.34 to 0.64)0.49 (0.36 to 0.68)<0.001
  • Factors showing statistical significance in univariate analysis (p<0.20) are shown. Multivariate ORs and 95% CIs were calculated from random effect logistic regression model and adjusted for age and sex.

  • Models were made separately for: (1) any helminth; (2) prevalence of Ascaris and Trichuris infection; (3) intensity of Ascaris and Trichuris infection.

  • epg, eggs per gram.

  • * Test for trend, p<0.001.

  • Numbers of missing values are given in parentheses.