Table 4.

Univariate and Multivariate Analyses for Factors Associated with Age at Onset.

Variables		Univariate				Multivariate
		Mean (SD)		p value		Regression coefficient (95%CI)		p value
(Intercept)						50.0 (42.9, 57.0)		<0.0001
Never-smoker-at-onset		51.7 (19.0)
Ever-smoker-at-onset		51.1 (13.4)		0.788		-3.67 (-8.82, 1.48)		0.162
Male		54.3 (14.1)
Female		49.0 (17.5)		0.028		-4.87 (-10.3, 0.535)		0.077
Anti-AChR antibody-negative		44.4 (14.1)
Anti-AChR antibody-positive		53.5 (16.3)		0.001		9.28 (3.54, 15.0)		0.002
Non-thymoma		52.2 (16.6)
Thymoma		49.5 (15.4)		0.313		-3.65 (-8.96, 1.66)		0.176

SD: standard deviation, CI: confidence interval, AChR: acetylcholine receptor