Table 1.

Risk of keratoconus (KC) associated with age, sex, tobacco smoking, co-occurrence of visual disturbances, body mass index (BMI), allergies and family history of KC.

Feature	Controls (n = 353)		KC (n = 284)		p	OR (95% CI)	pOR
	Number	Frequency	Number	Frequency
Sex					<0.001
females	223	0.63	85	0.30		0.24 (0.18–0.35)	<0.001
males	130	0.37	199	0.70		4.03 (2.88–5.62)	<0.001
Age					<0.001	0.92 (0.91–0.93)	<0.001
Mean ± SD	63 ± 18.9		36 ± 12.1
Range	19–100		14–68
Smoking					0.746
yes (current/former)	116	0.33	89	0.31		0.94 (0.67–1.32)	0.737
never	237	0.67	195	0.69		1.06 (0.76–1.48)	0.737
KC in family					<0.001
yes	8	0.02	33	0.12		5.61 (2.55–12.35)	<0.001
no	345	0.98	251	0.88		0.17 (0.08–0.39)	<0.001
BMI					0.578
≤25	149	0.42	131	0.46		1.16 (0.85–1.60)	0.347
25–30	119	0.34	92	0.32		0.94 (0.67–1.32)	0.729
≥30	85	0.24	61	0.21		0.87 (0.60–1.27)	0.470
Visual impairment					<0.001
yes	114	0.32	197	0.69		4.72 (3.36–6.62)	<0.001
no	239	0.68	87	0.31		0.21 (0.15–0.30)	<0.001
Allergies					<0.001
yes	44	0.12	80	0.28		2.77 (1.84–4.16)	<0.001
no	309	0.88	204	0.72		0.36 (0.24–0.54)	<0.001

p—values from χ² tests; except *—values from t-test, comparing KC patients and controls; p < 0.05 are in bold; OR—odds ratio; 95% CI—95% confidence interval; p_OR values <0.05 along with corresponding ORs are in bold.