In this prospective cross-sectional study, we enrolled 1106 subjects (mean age = 6.8, male-to-female ratio = 1.15:1) between June and September 2014. Subjects were recruited from B.C. Children's Hospital in Vancouver, Canada. Inclusion criteria was children <18 years of age; exclusion criteria was those seeking care for PAS. Subjects were visually inspected for the presence of PAS by clinical observers followed by verbal questionnaire (demographics, self-identified ethnicity, family history of PAS, chronic medical conditions). Data analysis utilized Pearson Chi-Square Test to determine the potential ethnic variation, and odds ratios of family history were used to determine a potential genetic basis.
26 (7 bilateral, 19 unilateral) of 1106 subjects were positive for PAS (2.4%). Using Pearson Chi-Square Test, a significant ethnic variation was found to exist (χ2 (6,N = 1106) = 22.80, p < 0.0001), with Asians having the highest prevalence (6.6%), followed by African Americans (4.5%), Middle Easterners (3.4%), First Nations (2.0%), and Caucasians (1.2%). None were found in South Asians (n = 124) or Latin Americans (n = 18). Subjects with positive family history of PAS had greater likelihood of having PAS (OR = 16.7, 95% CI = 7.3–38.5, p < 0.0001). There was also stronger association between family history and bilateral PAS (OR = 26.5, 95% CI = 5.8–121.7, p < 0.0001) compared to unilateral PAS (OR = 12.2, 95% CI = 4.6–32.5, p < 0.0001).
This was the largest pediatric population level study to date, and showed the prevalence of PAS was 2.4% in this pediatric population, whose ethnic diversity was representative of B.C.’s community. A significant ethnic variation existed and associations between family history and PAS suggested a potential genetic basis, particularly with bilateral PAS.