Table 2.

Incidence per 1000 person-years and hazard ratios (HR) of chronic otitis media with effusion during 11-year follow-up period.

				HR (95% CI)
	No. of participants	No. of cases	Incidence, per 1000 person-years	Unadjusted	Adjusted
Comparison group	14128	284	1.8	1 [Reference]	1 [Reference]
GERD group	3532	101	3.0	1.84 (1.46–2.32)	1.84 (1.46–2.31)
Sex
Male	9397	192	1.9	1[Reference]	1[Reference]
Female	8263	193	2.1	1.12 (0.92–1.37)	1.00 (0.82–1.23)
Age
20–29	1805	30	1.5	1 [Reference]	1 [Reference]
30–39	3435	60	1.6	1.04 (0.67–1.61)	0.99 (0.64–1.54)
40–49	4860	89	1.7	1.09 (0.72–1.64)	1.07 (0.70–1.61)
50–59	3985	110	2.5	1.64 (1.09–2.45)	1.63 (1.09–2.45)
60–69	2976	81	2.4	1.60 (1.05–2.43)	1.55 (1.02–2.36)
≥70	599	15	2.2	1.47 (0.79–2.73)	1.43 (0.77–2.67)
Comorbidities
Allergic rhinitis
No	9920	153	1.4	1 [Reference]	1 [Reference]
Yes	7740	232	2.7	1.90 (1.55–2.33)	1.69 (1.37–2.10)
Asthma
No	14,793	292	1.8	1 [Reference]	1 [Reference]
Yes	2867	93	2.9	1.61 (1.28–2.04)	1.29 (1.02–1.64)
Adenotonsillitis
No	16,990	360	1.9	1 [Reference]	1 [Reference]
Yes	670	25	3.4	1.75 (1.17–2.62)	1.47 (0.98–2.22)
Chronic rhinosinusitis
No	15,248	291	1.7	1 [Reference]	1 [Reference]
Yes	2412	94	3.5	2.01 (1.60–2.54)	1.61 (1.26–2.05)

GERD = gastroesophageal reflux disease.