Allergic rhinitis and associated risk of migraine among children: a nationwide population-based cohort study.
BACKGROUND
Increased frequency of migraine was reported in adults with allergic rhinitis (AR). Although migraine is less common in children than in adults, it can begin in early childhood and persist into adulthood. We conducted this population-based cohort study to investigate the incidence and subsequent risk of migraine in children with AR.


METHODS
From 2000 to 2007, 461,850 children with recently diagnosed AR and 460,718 non-AR controls were included in the study. By the end of 2008, incidences of migraine in both cohorts, the AR to non-AR cohort hazard ratios (HRs), and confidence intervals (CIs) were measured.


RESULTS
The incidence of migraine during the study period was 3.2-fold higher in the AR cohort (95% CI, 2.97 to 3.46) than in the non-AR cohort (11.4 vs 3.49 per 10000 person-years). The risk was greater for boys than for girls, and for children aged <6 years. The HR for migraine in children with AR was 1.44 (95% CI, 1.31 to 1.58) for those with ≤2 annual AR-related medical visits, whereas, 14.8 (95% CI, 13.6 to 16.2) for those with >4 visits (p < 0.0001, the trend test). The risk of migraine development in the AR cohort was highest within the first year after AR diagnosis (HR 4.89; 95% CI, 3.98 to 6.00). Children with AR were more likely to have migraine without aura than migraine with aura.


CONCLUSION
Children with AR had a higher incidence and subsequent risk of migraine. Physicians should be more aware of migraine in children with AR who complain of headache.
['Wang|I-Chung|IC|', 'Tsai|Jeng-Dau|JD|', 'Lin|Cheng-Li|CL|', 'Shen|Te-Chun|TC|', 'Li|Tsai-Chung|TC|', 'Wei|Chang-Ching|CC|']
D000328:Adult D002648:Child D002675:Child, Preschool D015331:Cohort Studies D005260:Female D006801:Humans D015994:Incidence D007223:Infant D008297:Male D008881:Migraine Disorders D044382:Population Groups D065631:Rhinitis, Allergic D012306:Risk D012737:Sex Factors D013624:Taiwan
allergic rhinitis migraine children cohort study hazard ratios confidence intervals