Table 3. Comparison of Serum Total Bilirubin and Indirect Bilirubin Among PD Patients According to PD Disease Severity and Controls.

	Total cases	Total bilirubin (µmol/L)	P value	Indirect bilirubin (µmol/L)	P value
Control	135	6.07 (5.67 - 6.51)		2.78 (2.50 - 3.09)
PD disease severity (based on H&Y stage)
Mild (1 - 2)	36	7.65 (6.71 - 8.72)	0.025	4.28 (3.68 - 4.97)	0.001
Moderate (2.5 - 3)	11	8.72 (6.89 - 11.04)	0.018	4.93 (3.79 - 6.42)	0.004
Severe (4 - 5)	14	5.56 (4.46 - 6.94)	0.328	2.96 (2.20 - 4.00)	0.717

Data are expressed as geometric mean (95% CI). All comparison were compared with control. The analysis was controlled by age and co-morbidities.