Table 1.

Characteristics of the rheumatoid arthritis cohort (1980–2007)

Variable	1980–1994 (n=349)	1995–2007 (n=464)	p-value
Age, years, mean (SD)	56.2 (15.9)	55.6 (15.5)	0.44
Female, n (%)	236 (68)	320 (69)	0.68
Rheumatoid factor +, n (%)	231 (66)	306 (66)	0.94
BMI at diagnosis, kg/m2, mean (SD)	26.8 (5.5)	28.6 (6.2)	<0.001
Smokers, current, n (%)	98 (28)	80 (17)	<0.001
ESR at diagnosis, mm/hr, mean (SD)	27.2 (22.1)	23.0 (19.0)	0.01
Highest ESR*, mm/hr, (mean (SD)	36.2 (26.7)	30.1 (24.7)	<0.001
Erosions/destructive changes*, n (%)	85 (24)	134 (29)	0.15
DMARDs*, n (%)	181 (52)	385 (83)	<0.001
Duration of follow-up, years, mean (SD)	14.6 (7.2)	5.9 (3.5)	--

^*During the first year of RA diagnosis

BMI = body mass index; DMARDs = disease modifying antirheumatic drugs; ESR = erythrocyte sedimentation rate