TABLE 2.

Plasma carotenoid concentrations in the cystic fibrosis (CF) patients and the healthy control subjects¹

	CF patients		Control subjects
	Lutein	Zeaxanthin	Lutein	Zeaxanthin
	nmol/L		nmol/L
1	85	34	182	81
2	67	<10	134	66
3	69	35	256	83
4	105	38	110	60
5	69	33	202	77
6	83	33	223	77
7	183	55	127	55
8	64	<10	136	43
9	66	<10	347	131
10	76	<10	182	81
x̄ ± SD	87 ± 36.1	27 ± 15.8	190 ± 72.1	75 ± 23.6

¹Plasma lutein and zeaxanthin concentrations were measured on the same day as the macular pigment densities were measured and the visual performance tests were conducted. Laboratory reference ranges for healthy persons are 105–370 nmol/L for lutein and 34–117 nmol/L for zeaxanthin 37). There was an overall significant difference in plasma concentrations of lutein (unpaired t test, P < 0.001) and zeaxanthin (unpaired t test, P < 0.001) between the 2 groups.