Serum levels of n-3 and n-6 polyunsaturated fatty acids in patients with systemic lupus erythematosus and their association with disease activity: a pilot study

Figures & data

Table 1. Characteristics of patients with systemic lupus erythematosus

Parameter	n = 30
Age (years)	47 ± 14
Female	29 (97)
Disease duration (years)	11 ± 7
SLEDAI (points)	9.55 ± 6.85
Musculoskeletal involvement	25 (83)
Haematological involvement	16 (53)
Neuropsychiatric lupus	15 (50)
Skin involvement	15 (50)
Lupus nephritis	10 (33)
Lung involvement	6 (20)
Antiphospholipid syndrome	5 (17)
Vasculitis	2 (7)
CRP (mg/L)	12.1 ± 28.4
ESR (mm/h)	25 ± 18
anti-dsDNA antibody (IU/mL)	208.7 ± 264.1
ANA positive	29 (96)
Low C3 (< 0.9 g/L)	15 (50)
Low C4 (< 0.1 g/L)	6 (20)
Anti-phospholipid antibody positive	9 (30)
Proteinuria > 500 mg/24 h	3 (10)
Taking anti-malarials	19 (63)
Taking GCs	28 (93)
< 10 mg/day	17 (57)
> 10 mg/day	11 (37)
Treatment with immunosuppressants	17 (57)

Data are shown as mean ± sd or n (%).

ANA, anti-nuclear antibody; anti-dsDNA, anti-double-stranded DNA antibody; CRP, C-reactive protein; C3, complement 3; C4, complement 4; ESR, erythrocyte sedimentation rate; GCs, glucocorticoids; SLEDAI, Systemic Lupus Erythematosus Activity Index.

Table 2. Serum polyunsaturated fatty acid concentrations (mg/L) in systemic lupus erythematosus (SLE) patients and healthy controls

	SLE (n = 30)	Healthy controls (n = 20)	p
LA	8965.5 ± 865.2	2289.5 ± 689.3	0.006
AA	619.3 ± 350.8	552.6 ± 244.6	0.475
ALA	23.3 ± 15.2	16.1 ± 15.4	0.029
EPA	144.3 ± 78.2	122.7 ± 68.6	0.153
DHA	564.3 ± 378.9	468.7 ± 224.0	0.303

Data are shown as mean ± sd.

p-Values are given according to the Mann–Whitney U-test.

AA, arachidonic acid; ALA, α-linolenic acid; DHA, docosahexaenoic acid; EPA, eicosapentaenoic acid; LA, linoleic acid.

Table 3. Correlations between serum polyunsaturated fatty acid concentrations and systemic lupus erythematosus activity parameters

Parameter	LA	AA	ALA	EPA	DHA
Duration of disease	0.131	0.131	0.184	0.133	−0.097
SLEDAI	0.148	−0.943	−0.124	−0.125	0.105
ESR	−0.165	−0.132	−0.112	−0.060	−0.243
CRP	−0.114	−0.293	−0.096	−0.155	−0.159
C3 level	−0.102	−0.046	0.173	−0.170	−0.272
C4 level	0.157	0.423	0.512	0.342	−0.048
ANA titre	0.387*	−0.167	−0.167	0.039	0.130
dsDNA level	−0.240	−0.399*	−0.258	−0.384*	−0.372*
Dose of steroids	0.493*	−0.275	−0.246	−0.095	0.326

Data are shown as r.

*p < 0.05; p-values are given according to the Pearson’s correlation coefficient.

AA, arachidonic acid; ALA, α-linolenic acid; ANA, anti-nuclear antibody; anti-dsDNA, anti-double-stranded DNA antibody; CRP, C-reactive protein; C3, complement 3; C4, complement 4; DHA, docosahexaenoic acid; EPA, eicosapentaenoic acid; ESR, erythrocyte sedimentation rate; LA, linoleic acid; SLEDAI, Systemic Lupus Erythematosus Activity Index.

Table 4. Polyunsaturated fatty acid serum concentrations in systemic lupus erythematosus patients with and without immunosuppressive treatment (mg/L)

	Without treatment (n = 17)	With treatment (n = 13)	p
LA	12403.7 ± 9811.3	4071.9 ± 3600.1	0.009
AA	747.6 ± 332.7	434.5 ± 317.5	0.017
ALA	27.6 ± 16.2	17.2 ± 12.8	0.074
EPA	169.6 ± 69.5	110.4 ± 82.6	0.046
DHA	675.7 ± 392.1	410.1 ± 331.3	0.066

Data are shown as mean ± sd.

p-Values are given according to the Mann–Whitney U-test.

AA, arachidonic acid; ALA, α-linolenic acid; DHA, docosahexaenoic acid; EPA, eicosapentaenoic acid; LA, linoleic acid.