A population-based questionnaire survey on the prevalence of peanut, tree nut, and shellfish allergy in 2 Asian populations.
BACKGROUND
There has been a substantial increase in the prevalence of peanut and tree nut allergy in Western populations in the last 2 decades. However, there is an impression that peanut and tree nut allergy is relatively uncommon in Asia.


OBJECTIVE
To evaluate the prevalence of peanut, tree nut, and shellfish allergy in schoolchildren in 2 Asian countries (Singapore and Philippines).


METHODS
A structured written questionnaire was administered to local and expatriate Singapore (4-6 and 14-16 years old) and Philippine (14-16 years old) schoolchildren.


RESULTS
A total of 25,692 schoolchildren responded to the survey (response rate, 74.2%). Of these, 23,425 responses fell within the study protocol's 4 to 6 and 14 to 16 year age groups and were included in the analysis. The prevalence of convincing peanut and tree nut allergy were similar in both local Singapore (4-6 years, 0.64%, 0.28%; 14-16 years, 0.47%, 0.3%, respectively) and Philippine (14-16, 0.43%, 0.33%, respectively) schoolchildren, but was higher in the Singapore expatriates (4-6 years, 1.29%, 1.12%; 14-16 years, both 1.21%, respectively; 4-6 years, expatriates vs local Singaporeans: peanut, P = .019; tree nut, P = .0017; 14-16 years, P > .05). Conversely, shellfish allergy was more common in the local Singapore (4-6 years, 1.19%; 14-16 years, 5.23%) and Philippine (14-16 years, 5.12%) schoolchildren compared with expatriate children (4-6 years, 0.55%; 14-16 years, 0.96%; P < .001). When data were pooled, respondents born in Western countries were at higher risk of peanut (adjusted odds ratios [95% CIs]: 4-6 years, 3.47 [1.35-8.93]; 14-16 years, 5.56 [1.74-17.76]) and tree nut allergy (adjusted odds ratios [95% CIs]: 4-6 years, 10.40 [1.61-67.36]; 14-16 years, 3.53 [1.00-12.43]) compared with those born in Asia.


CONCLUSIONS
This study substantiates the notion that peanut and tree nut allergy is relatively low in Asian children, and instead shellfish allergy predominates. Environmental factors that are yet to be defined are likely to contribute to these differences.
Shek
Lynette Pei-Chi
LP
National University Health System, Singapore.
Cabrera-Morales
Elizabeth Ann
EA
Soh
Shu E
SE
Gerez
Irvin
I
Ng
Pau Zhing
PZ
Yi
Fong Cheng
FC
Ma
Stefan
S
Lee
Bee Wah
BW
D000293:Adolescent; D000367:Age Factors; D044466:Asian People; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D021184:Nut Hypersensitivity / Q000453:epidemiology*; D021183:Peanut Hypersensitivity / Q000453:epidemiology*; D010679:Philippines / Q000453:epidemiology; D015995:Prevalence; D012307:Risk Factors; D012758:Shellfish / Q000009:adverse effects*; D012846:Singapore / Q000453:epidemiology; D011795:Surveys and Questionnaires