Table 2.

Unadjusted means and 95% confidence limits (CL) of circulating concentrations (ng/mL) of omega-3 (n-6) and omega-6 (n-3) essential fatty acids and long-chain polyunsaturated fatty acids in erythrocyte membranes, stratified by TMD and low back pain case status

	Painful TMD non-case (n=333)		Painful TMD case (n=170)
	Mean	95% CL	Mean	95% CL	P
Linoleic acid 18:2n-6	1088.6	979.1, 1198.0	1172.5	1019.3, 1325.7	0.381
α-linolenic acid 18:3n-3	77.1	70.0, 84.1	81.4	71.6, 91.3	0.478
Arachidonic acid 20:4n-6	76.6	69.9, 83.4	83.9	74.5, 93.3	0.219
Eicosapentaenoic acid 20:5n-3	101.5	90.2, 112.8	95.1	79.3, 111.0	0.520
Docosahexaenoic acid 22:6n-3	19.2	17.0, 21.3	17.9	14.9, 20.9	0.493
n-6/n-3 PUFA ratio (×100)	86.8	81.3, 92.3	99.9	92.2, 107.6	0.007
	Low back pain non-case (n=381)		Low back pain case (n=122)
	Mean	95% CL	Mean	95% CL	P
Linoleic acid 18:2n-6	1140.2	1037.9, 1242.5	1044.3	863.5, 1225.1	0.365
α-linolenic acid 18:3n-3	79.3	72.8, 85.9	76.1	64.5, 87.7	0.634
Arachidonic acid 20:4n-6	76.5	70.2, 82.8	87.2	76.1, 98.4	0.099
Eicosapentaenoic acid 20:5n-3	99.8	89.2, 110.4	98.0	79.3, 116.7	0.872
Docosahexaenoic acid 22:6n-3	19.7	17.7, 21.7	15.6	12.1, 19.1	0.043
n-6/n-3 PUFA ratio (×100)	87.9	82.8, 93.1	101.4	92.4, 110.5	0.011