Table 2.

Concentrations of free fatty acids (µmol/l) determined in the serum of ALS patients and healthy controls

Analyte (µmol/l)	ALS patients (n = 100), median (IQR)	Healthy controls (n = 34), median (IQR)	P value (Mann–Whitney test)
FFA	951.36 (660.9–1286.7)	595.9 (415.4–736.1)	< 0.0001*
SCFA	110.8 (85.6–839.8)	263.2 (220.3–598.2)	0.019
MCFA	20.8 (14.6–26.7)	14.7 (9.4–18.7)	< 0.0001*
LCFA	711.2 (492.8–880.7)	330.0 (175.1–417.5)	< 0.0001*
Acetic acid	71.85 (71.85–336–673)	191.50 (141.71–227.71)	0.0270
Propionic acid	4.37 (4.27–6–55)	16.69 (12.5–21.45)	< 0.0001*
Butyric acid	6.60 (3.30–17.25)	5.51 (3.18–6.75)	0.014
Isobutyric acid	2.00 (1.67–3.34)	12.30 (8.42–18.18)	< 0.0001*
Isovaleric acid	1.65 (1.65–3.30)	15.78 (10.37–21.12)	< 0.0001*
2-Methylbutyric acid	1.88 (1.71–1.88)	8.92 (5.88–12.94)	< 0.0001*
Valeric acid	0.34 (0.17–0.59)	0.64 (0.34–0.85)	< 0.0001*
Hexanoic acid	0.43 (0.43–0.43)	1.90 (1.36–2.79)	< 0.0001*
Heptanoic acid	0.30 (0.15–0.45)	1.03 (0.45–3.04)	< 0.0001*
Nonanoic acid	0.33 (0.28–0.82)	0.24 (0.05–0.55)	< 0.0001*
2-Ethylhexanoic acid	3.44 (1.72–9.72)	3.56 (1.30–8.68)	0.081
Octanoic acid	1.43 (1.43–1.43)	0.77 (0.47–2.14)	0.092
Decanoic acid	1.18 (1.18–1.75)	0.41 (0.08–1.09)	< 0.0001*
Benzoic acid	8.02 (4.01–12.03)	1.65 (1.49–2.02)	< 0.0001*
Dodecanoic acid	1.29 (1.17–2.77)	2.45 (1.61–4.49)	< 0.0001*
Tetradecanoid acid	8.21 (5.20–13.12)	14.73 (8.28–24.18)	< 0.0001*
Hexadecanoic acid	541.04–399.20)	250.0 (116.25–317.22)	< 0.0001*
Octadecanoic acid	67.32 (47.36–228.49)	64.6 (38.96–91.19)	0.0310

P-values were calculated with Mann–Whitney test. ^*p-value adj < 0.0022