Table 1.
Association between Elaeis guineensis (oil palm) pollen sensitization and the risk of allergic diseases in the Singapore/Malaysia Chinese population.
| Total (n = 13 652) |
||||
|---|---|---|---|---|
|
Elaeis guineensis Positive SPT |
Elaeis guineensis Negative SPT |
P-value | OR (95% CI) | |
| Case/Control (%Case) | Case/Control (%Case) | |||
| Asthmaa | 152/417 (26.7) | 1713/7235 (19.1) | 1.34 x 10−4∗ | 1.47 (1.20–1.78) |
| Allergic Rhinitis (AR)b | 331/188 (63.8) | 3901/4379 (47.1) | 2.91 x 10−13∗ | 2.01 (1.67–2.43) |
| Atopic Dermatitis (AD)c | 150/386 (28) | 1757/7104 (19.8) | 6.95 x 10−7∗ | 1.65 (1.35–2.00) |
| Single allergic disease only (Asthma-only or AR-only or AD-only) | 240/110 (68.6) | 3678/2841 (56.4) | 3.77 x 10−6∗ | 1.75 (1.38–2.22) |
| At least one allergic disease (Asthma or AR or AD) | 421/110 (79.3) | 5385/2841 (65.5) | 7.86 x 10−11∗ | 2.08 (1.68–2.61) |
| More than one allergic disease (disease multimorbidity) | 181/110 (62.2) | 1707/2841 (37.5) | 8.35 x 10−16∗ | 2.80 (2.19–3.61) |
| Asthma + AR | 96/148 (39.3) | 893/3553 (20.1) | 9.67 x 10−11∗ | 2.51 (1.89–3.31) |
| Asthma + AD | 45/270 (14.3) | 424/5289 (7.4) | 2.23 x 10−5∗ | 2.07 (1.46–2.87) |
| AR + AD | 102/137 (42.7) | 948/3448 (21.6) | 4.49 x 10−14∗ | 2.83 (2.16–3.70) |
| Asthma + AR + AD | 31/110 (22) | 279/2841 (8.9) | 2.34 x 10−6∗ | 2.84 (1.81–4.32) |
CI: confidence interval; OR: odds ratio; SPT: skin prick test. All data were evaluated based on skin prick test results of the Elaeis guineensis (oil palm) pollen allergen in a cross-sectional cohort of Singapore/Malaysia Chinese individuals (n = 13 652). P-value, odds ratio, and 95% CI were calculated using a logistic regression analysis with adjustment for age and gender.
∗Logistic p < 0.05 is considered as significant.
Allergic asthma case was defined as ever having asthma positively diagnosed by a physician (Based on ISAAC questionnaire). Non-asthma control was defined as no symptoms and history of asthma.
Allergic rhinitis (AR) case is defined by 2 or more self-reported rhinitis symptoms. Non-AR control was defined as no symptoms and history of AR.
Atopic Dermatitis (AD) case is defined as having a persistent itchy rash that affected flexural areas. Non-AD control was classified based on no symptoms and history of AD