TABLE 1.
Frequencies of maternal and childhood geohelminth infections to 5 years of age and potential confounders and associations with wheeze and allergen skin test (SPT) reactivity to any allergen at 8 years and asthma between 5 and 8 years
| Overall | Wheeze | Asthma | SPT to any allergen | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Variable | n (%) | % | OR (95% CI) | p value | % | OR (95% CI) | p value | % | OR (95% CI) | p value |
| Any maternal geohelminth | ||||||||||
| No | 1048 (54.2) | 6.2 | 1 | 8.2 | 1 | 16.8 | 1 | |||
| Yes | 885 (45.8) | 7.0 | 1.14 (0.79–1.63) | .478 | 7.6 | 0.92 (0.66–1.28) | .606 | 12.2 | 0.69 (0.53–0.89) | .005 |
| Any childhood geohelminths | ||||||||||
| No | 1054 (54.5) | 6.7 | 1 | 8.4 | 1 | 16.4 | 1 | |||
| Yes | 879 (45.5) | 6.4 | 0.94 (0.66–1.35) | .747 | 7.4 | 0.88 (0.63–1.22) | .439 | 13.0 | 0.75 (0.59–0.98) | .034 |
| Maternal age (years) | ||||||||||
| ≤20 | 501 (25.9) | 5.8 | 1 | 6.6 | 1 | 13.8 | 1 | |||
| 21–29 | 929 (48.1) | 6.6 | 1.14 (0.72–1.80) | .564 | 8.7 | 1.35 (0.89–2.06) | .157 | 14.0 | 1.01 (0.74–1.40) | .908 |
| ≥30 | 503 (26.0) | 7.4 | 1.29 (0.78–2.14) | .317 | 7.8 | 1.19 (0.74–1.93 | .474 | 16.9 | 1.27 (0.90–1.80) | .170 |
| Maternal ethnicity | ||||||||||
| Afro-Ecuadorian | 508 (26.3) | 7.7 | 1 | 11.8 | 1 | 14.8 | 1 | |||
| Non-Afro-Ecuadorian | 1425 (73.7) | 6.2 | 0.79 (0.54–1.17) | .242 | 6.5 | 0.52 (0.37–0.73) | <.001 | 14.7 | 0.99 (0.75–1.32) | .958 |
| Maternal educational level | ||||||||||
| Illiterate | 293 (15.2) | 5.5 | 1 | 8.2 | 1 | 14.7 | 1 | |||
| Complete primary | 1133 (58.6) | 6.2 | 1.14 (0.65–1.99) | .646 | 7.3 | 0.89 (0.55–1.42) | .616 | 13.7 | 0.92 (0.64–1.33) | .661 |
| Complete Secondary | 507 (26.2) | 8.2 | 1.52 (0.84–2.77) | .167 | 9.1 | 1.12 (0.67–1.87) | .671 | 17.0 | 1.19 (0.89–1.77) | .397 |
| Area of residence | ||||||||||
| Urban | 1346 (69.6) | 7.4 | 1 | 9.4 | 1 | 15.5 | 1 | |||
| Rural | 587 (30.4) | 4.6 | 0.60 (0.39–0.93) | .022 | 4.6 | 0.47 (0.30–0.72) | <.001 | 13.0 | 0.81 (0.61–1.08) | .153 |
| Sex | ||||||||||
| Male | 984 (50.9) | 7.9 | 1 | 8.7 | 1 | 16.5 | 1 | |||
| Female | 949 (49.1) | 5.2 | 0.63 (0.44–0.91) | .015 | 7.1 | 0.79 (0.57–1.11) | .172 | 12.9 | 0.75 (0.58–0.96) | .025 |
| Socio-economic statusa | ||||||||||
| 1 | 642 (33.2) | 6.2 | 1 | 7.8 | 1 | 13.4 | 1 | |||
| 2 | 638 (33.0) | 5.6 | 0.90 (0.57–1.43) | .656 | 7.2 | 0.92 (0.61–1.40) | .695 | 14.0 | 1.05 (0.76–1.44) | .773 |
| 3 | 653 (33.8) | 7.8 | 1.28 (0.83–1.96) | .267 | 8.7 | 1.13 (0.76–1.68) | .539 | 16.7 | 1.30 (0.95–1.76) | .098 |
| Birth order | ||||||||||
| 1st | 490 (25.4) | 6.1 | 1 | 5.5 | 1 | 16.7 | 1 | |||
| 2nd–4th | 1063 (55.0) | 7.3 | 1.21 (0.79–1.88) | .382 | 9.4 | 1.78 (1.15–2.76) | .010 | 13.5 | 1.05 (0.76–1.44) | .088 |
| ≥5th | 380 (19.6) | 5.0 | 0.81 (0.45–1.46) | .477 | 6.8 | 1.26 (0.72–2.20) | .416 | 15.5 | 1.30 (0.95–1.76) | .632 |
| Maternal allergy | ||||||||||
| No | 1830 (95.4) | 6.3 | 1 | 7.7 | 1 | 14.4 | 1 | |||
| Yes | 89 (4.6) | 12.4 | 2.10 (1.09–4.06) | .027 | 14.6 | 2.06 (1.12–3.81) | .020 | 18.0 | 1.30 (0.75–2.27) | .355 |
| Household overcrowdingb | ||||||||||
| ≤3 | 1086 (56.2) | 6.5 | 1 | 7.6 | 1 | 15.6 | 1 | |||
| >3 | 847 (43.8) | 6.6 | 1.01 (0.70–1.45) | .948 | 8.4 | 1.12 (0.80–1.56) | .502 | 13.6 | 0.85 (0.66–1.10) | .222 |
| Pets inside house | ||||||||||
| No | 1438 (74.4) | 6.3 | 1 | 7.7 | 1 | 14.5 | 1 | |||
| Yes | 495 (25.6) | 7.3 | 1.16 (0.78–1.73) | .465 | 8.7 | 1.15 (0.79–1.66) | .461 | 15.2 | 1.05 (0.79–1.40) | .738 |
| Large farm animalsc | ||||||||||
| No | 1294 (66.9) | 7.0 | 1 | 8.0 | 1 | 15.8 | 1 | |||
| Yes | 639 (33.1) | 5.8 | 0.82 (0.55–1.22) | .331 | 7.7 | 0.95 (0.67–1.35) | .778 | 12.5 | 0.76 (0.58–1.01) | .058 |
| Pneumonia to 13 months | ||||||||||
| No | 1758 (95.3) | 6.6 | 1 | 7.9 | 1 | 15.0 | 1 | |||
| Yes | 90 (4.7) | 5.6 | 0.83 (0.33–2.09) | .697 | 7.8 | 0.99 (0.45–2.18) | .980 | 7.8 | 0.48 (0.22–1.04) | .064 |
Note: SPT—allergen skin prick test reactivity to any of 9 allergens. Odds ratios (OR) and 95% confidence intervals (95% CI) for univariable associations were estimated using logistic regression. p < .05 are shown in bold. Ethnicity ‘other’ represents: 1417 Mestizo/8 Indigenous. Numbers of missing values (brackets) were as follows: maternal allergy (14) and pneumonia during first 13 months (85). Other helminths: mother (S. stercoralis, 4.0%; Hymenolepis spp., 0.5%); child (hookworm, 1.1%; S.stercoralis, 1.5%; Hymenolepis spp., 4.2%).
Socio-economic status (SES) represents tertiles of z scores obtained using a factor analysis with 1 representing the lowest and 3 the highest SES.
Household overcrowding is defined as the number of people living in the household per sleeping room.
Any of cows, pigs, mules, donkeys and horses.