. Author manuscript; available in PMC: 2013 Mar 1.

Published in final edited form as: Autoimmunity. 2011 Oct 20;45(2):161–168. doi: 10.3109/08916934.2011.616557

Table 2.

Characteristics of Pre-RA Cases and Matched Healthy Women within a Nested Case-Control Study in the Nurses’ Health Study Cohorts

	Pre-RA Cases (n=87)	Controls (n=87)
Matching factors at blood draw
Age, mean (±SD)	54.9 (8.3)	54.8 (±8.2)
Postmenopausal, (%)	55 (63)	55 (63)
Postmenopausal hormone use at blood draw, (%)	33 (60)	33 (60)
Other Characteristics			p^*
Caucasian, (%)	87 (100.0)	85 (97.7)	0.50
Ever cigarette smokers, (%)	48 (55.2)	50 (57.5)	0.87
Pack-years among smokers, mean (±SD)	19.9 (14.6)	23.3 (21.1)	0.84
Age at menarche < 12 years, (%)	16 (18.6)	16 (18.4)	1.0
Parous, (%)	83 (95.4)	82 (95.4)	0.75
Alcohol intake in gms/day, mean (±SD)	3.6 (3.4)	5.0 (5.6)	0.94
Body mass index in kg/m², mean (±SD)	26.2 (4.8)	26.1 (5.1)	0.62

p value from Fisher’s exact tests for categorical variables and t-tests for continuous variables.