Table 3.

Risk of urticaria as a function of follow-up time in individuals with celiac disease.

Follow-up	Observed events (N)	Expected events (N)	HR; 95% CI	P-value	Absolute risk/100,000 PYAR	Excess risk/100,000 PYAR	Attributable percentage (%)
Urticaria
All	453	300	1.51; 1.36–1.68	<0.001	140	47	34
Excluding first year	412	271	1.52; 1.36–1.70	<0.001	212	73	34
<1 year	41	29	1.43; 1.02–2.02	0.038	144	43	30
1–4.99 years	144	98	1.47; 1.22–1.76	<0.001	135	43	32
≥5 years	268	173	1.55; 1.36–1.78	<0.001	143	51	35
Chronic urticaria (≥6 weeks)
All	79	41	1.92; 1.48–2.48	<0.001	24	12	48
Excluding first year	76	37	2.04; 1.57–2.66	<0.001	26	13	51
<1 year	3	4	0.76; 0.23–2.52	0.653	10	−3	−32
1–4.99 year	37	13	2.96; 2.00–4.40	<0.001	34	23	66
≥5 year	39	25	1.58; 1.11–2.27	0.012	21	8	37

HR, Hazard ratio; CI, Confidence interval; PYAR, Person-years at risk.

Reference is general population comparator cohort.

#Expected number of events in patients with celiac disease was derived from the observed number of events divided by the HR.