Table 8.

Medical and/or psychiatric comorbidities in the 300 primary headache patients and comparison between chronic and episodic headache patients

Number of comorbidities	Total (n = 300), n (%)	Episodic headache (n = 181), n (%)	Chronic headache (n = 119), n (%)	OR [95% CI]a	P valueb
At least 1	179/300 (59.7)	98/181 (54.1)	81/119 (68.1)	1.81 [1.11–2.94]	0.0164
1	107/300 (35.7)	68/181 (37.6)	39/119 (32.8)	0.81 [0.50–1.32]	0.3970
2	52/300 (17.3)	22/181 (12.2)	30/119 (25.2)	2.44 [1.31–4.52]	0.0035
>2	20/300 (6.7)	8/181 (4.4)	12/119 (10.1)	2.43 [0.95–6.17]	0.0548

CI confidence interval, OR odds ratio

^achronic vs episodic headache OR

^bp value is derived from a Chi square test for homogeneity of odds