Table 1.

Risk factors for surgically treated CTS among non-retired subjects

			Univariate	Multivariate*
	Cases (n = 191)	Controls (n = 286)	OR (95% CI)	OR (95% CI)
Socio-occupational status
White collar	19	134	1.0	1.0
Blue collar/housewife†	172	152	8.0 (4.5-14.2)	7.1 (4.0-12.7)
BMI (kg/m2)
<25	80	167	1.0	1.0
25-29	69	91	1.6 (1.0-2.4)	1.4 (0.9-2.4)
≥30	41	25	3.4 (1.9-6.1)	3.3 (1.6-6.6)
Height, cm
<165 (women) or <175 (men)	149	165	1.0	1.0
≥165 (women) or ≥175 (men)	41	121	0.4 (0.2-0.6)	0.5 (0.3-0.8)
Alcohol consumption
Never	67	83	1.0	1.0
1-2 drinks/wk	37	56	0.8 (0.5-1.4)	0.8 (0.4-1.6)
3-6 drinks/wk	11	26	0.5 (0.2-1.1)	0.4 (0.1-1.1)
1-2 drinks/day	56	80	0.9 (0.5-1.4)	0.8 (0.5-1.5)
3 drinks/day or more	20	41	0.6 (0.3-1.1)	0.7 (0.3-1.6)
Family history of CTS
None	160	260	1.0	1.0
Father/mother	15	22	1.1 (0.6-2.2)	1.3 (0.5-3.1)
Sibling	15	3	8.1 (2.3-29.2)	6.6 (1.5-29.4)
Rheumatoid arthritis
No	160	267	1.0	1.0
Yes	30	19	2.6 (1.4-4.9)	2.2 (1.0-4.6)
Trigger finger
No	157	271	1.0	1.0
Yes	33	15	3.8 (2.0-7.3)	2.7 (1.3-5.8)
Diabetes mellitus
No	181	280	1.0	1.0
Yes	9	6	2.3 (0.8-6.7)	2.6 (0.7-8.7)
Renal failure
No	187	282	1.0
Yes	3	4	1.1 (0.2-5.1)
Thyroid disorders
No	163	253	1.0
Yes	27	33	1.3 (0.7-2.2)
Wrist fractures
None	180	262	1.0
At least one	11	24	0.7 (0.3-1.4)
Smoking status
Never	103	147	1.0
Former	31	65	0.7 (0.4-1.1)
Current	57	73	1.1 (0.7-1.7)
Education level
Below high school diploma	152	138	1.0
High school diploma or higher	39	148	0.2 (0.2-0.4)

*Multivariate unconditional logistic regression model adjusted for socio-occupational status, BMI, height, alcohol, family history of CTS, rheumatoid arthritis, trigger finger and diabetes mellitus (ie all the variables apart from education level that reached p < 0.1 at univariate analysis), as well as age and gender (the two variables used for frequency matching, which were included to reduce residual confounding) and center.

†The grouping of housewives with blue-collar workers was based on biomechanical considerations.