Table 4. Relative Risk (RR) of Psoriasis according to Weight Change between Age of 18 Years and Updated Follow-up.

Variable	< −5 lbs	−5 to +4.9	+5 to +19.9	+20 to +34.9	>+35	10 lbs increment	P for 10 lbs increment
Incident cases of psoriasis	40	43	120	162	357
Person-years	47,026	63,705	160,801	187,244	325,120
Age-adjusted RR (95% CI)	1.21 (0.79, 1.87)	1.0 (Ref)	1.10 (0.78, 1.57)	1.29 (0.92, 1.81)	1.63 (1.19, 2.24)	1.07 (1.05, 1.10)	<0.0001
Multivariate-adjusted RR (95% CI) *	1.06 (0.69, 1.64)	1.0 (Ref)	1.16 (0.81, 1.64)	1.40 (0.99, 1.96)	1.79 (1.29, 2.47)	1.08 (1.06, 1.11)	<0.0001

^*The multivariate adjusted model includes age, alcohol consumption, smoking status, physical activity and BMI at age of 18 years.