Background
Methods
Study design
Metabolomics analysis of serum samples
Statistical analysis
Results
Characteristics of the study population
Cases | Controls | |||||
---|---|---|---|---|---|---|
All | Female | Male | All | Female | Male | |
N | 202 | 133 | 69 | 166 | 110 | 56 |
Age (years) | 75.8 ± 4.4 | 76.1 ± 4.4 | 75.2 ± 4.5 | 75.1 ± 4.1 | 75.5 ± 4.0 | 74.4 ± 4.2 |
Sex (% female) | 65.8 | - | - | 66.3 | - | - |
Education level, ≥ secondary school (%) | 29.7 | 30.1 | 29.0 | 31.9 | 31.8 | 32.1 |
ApoE-ε4+ frequency (%) | 25.7 | 25.6 | 26.1 | 12.0 | 13.6 | 8.9 |
BMI (kg m-2) | 26.8 ± 4.3 | 26.4 ± 4.6 | 27.6 ± 3.7 | 26.3 ± 3.7 | 26.1 ± 4.2 | 26.7 ± 2.6 |
Number of medications regularly consumed | 4.9 ± 2.8 | 5.2 ± 2.7 | 4.2 ± 2.7 | 3.9 ± 2.3 | 4.1 ± 2.1 | 3.4 ± 2.7 |
MMSE (points) | 27.0 ± 2.2 | 27.0 ± 2.2 | 26.9 ± 2.2 | 27.9 ± 1.7 | 27.8 ± 1.8 | 28.2 ± 1.4 |
BVRT (points) | 10.8 ± 2.1 | 10.6 ± 2.1 | 11.1 ± 2.1 | 11.8 ± 1.9 | 11.6 ± 2.0 | 12.2 ± 1.7 |
IST (points) | 27.8 ± 5.8 | 27.7 ± 5.7 | 28.0 ± 6.4 | 31.2 ± 6.1 | 31.2 ± 6.4 | 31.1 ± 5.7 |
TMTA (number of correct displacements per minute) | 24.1 ± 8.0 | 23.5 ± 7.7 | 25.4 ± 8.5 | 29.3 ± 9.3 | 29.1 ± 9.3 | 29.7 ± 9.4 |
TMTB (number of correct displacements per minute) | 10.0 ± 5.8 | 9.8 ± 5.5 | 10.6 ± 6.5 | 14.5 ± 6.7 | 14.4 ± 6.7 | 14.8 ± 6.6 |
Glucose (mmol L-1) | 5.5 ± 1.6 | 5.4 ± 1.8 | 5.5 ± 1.3 | 5.1 ± 1.0 | 4.9 ± 0.7 | 5.6 ± 1.4 |
Creatinine (mmol L-1) | 83.1 ± 22.5 | 75.9 ± 14.2 | 97.0 ± 28.3 | 79.3 ± 18.1 | 73.6 ± 14.9 | 90.7 ± 18.5 |
Cholesterol (mmol L-1) | 5.8 ± 0.9 | 5.9 ± 0.9 | 5.6 ± 0.9 | 5.8 ± 1.0 | 5.9 ± 1.0 | 5.7 ± 0.9 |
LDL-C (mmol L-1) | 3.6 ± 0.8 | 3.7 ± 0.8 | 3.6 ± 0.8 | 3.6 ± 0.9 | 3.7 ± 1.0 | 3.6 ± 0.7 |
HDL-C (mmol L-1) | 1.6 ± 0.4 | 1.7 ± 0.4 | 1.4 ± 0.4 | 1.6 ± 0.4 | 1.6 ± 0.4 | 1.4 ± 0.3 |
Triglycerides (mmol L-1) | 1.4 ± 0.8 | 1.3 ± 0.7 | 1.4 ± 0.9 | 1.3 ± 0.7 | 1.2 ± 0.5 | 1.4 ± 0.9 |
Impact of ApoE-ε4 genotype and sex on circulating levels of fatty acid-related metabolites in a prospective cohort on CD
Whole study population | ApoE-ε4 stratification | Sex stratification | |||||||
---|---|---|---|---|---|---|---|---|---|
CD vs. CTL | CDε4+ vs. CTLε4+ | CDε4- vs. CTLε4- | CTLε4+ vs. CTLε4- | CDε4+ vs. CDε4- | CDF vs. CTLF | CDM vs. CTLM | CTLF vs. CTLM | CDF vs. CDM | |
Free fatty acids | |||||||||
Myristic acid | 1.38 (3.1·10-2) | 1.05 (NS) | 1.39 (6.0·10-2) | 1.12 (NS) | 1.08 (NS) | 1.53 (3.3·10-2) | 1.13 (NS) | 1.49 (NS) | 2.03 (1.3·10-2) |
Palmitic acid | 1.09 (NS) | 0.50 (5.3·10-2) | 1.27 (NS) | 2.22 (3.9·10-3) | 0.87 (NS) | 1.16 (NS) | 0.97 (NS) | 0.90 (NS) | 1.07 (NS) |
Palmitoleic acid | 1.14 (NS) | 0.60 (NS) | 1.29 (NS) | 2.08 (1.1·10-2) | 0.96 (NS) | 1.22 (NS) | 1.00 (NS) | 1.25 (NS) | 1.51 (6.4·10-2) |
Margaric acid | 1.13 (NS) | 0.81 (NS) | 1.21 (NS) | 1.56 (NS) | 1.05 (NS) | 1.18 (NS) | 1.05 (NS) | 0.97 (NS) | 1.08 (NS) |
Stearic acid | 1.03 (NS) | 0.39 (5.5·10-3) | 1.25 (NS) | 2.47 (1.7·10-3) | 0.78 (NS) | 1.07 (NS) | 0.96 (NS) | 0.88 (NS) | 0.98 (NS) |
Oleic acid | 1.19 (NS) | 0.50 (7.8·10-2) | 1.41 (2.2·10-2) | 2.28 (2.3·10-3) | 0.80 (NS) | 1.26 (NS) | 1.06 (NS) | 0.99 (NS) | 1.18 (NS) |
Linoleic acid | 1.22 (9.7·10-2) | 0.78 (NS) | 1.25 (2.2·10-2) | 1.62 (4.4·10-2) | 0.94 (NS) | 1.29 (6.1·10-2) | 1.10 (NS) | 0.86 (NS) | 1.01 (NS) |
Linolenic acid | 1.12 (NS) | 0.65 (NS) | 1.25 (6.7·10-2) | 1.74 (9.0·10-3) | 0.91 (NS) | 1.26 (7.8·10-2) | 0.89 (NS) | 0.93 (NS) | 1.32 (NS) |
Arachidonic acid | 1.05 (NS) | 0.60 (NS) | 1.18 (NS) | 1.87 (6.0·10-3) | 0.95 (NS) | 1.15 (NS) | 0.89 (NS) | 0.78 (8.2·10-2) | 1.01 (NS) |
Eicosapentaenoic acid | 0.99 (NS) | 0.68 (7.8·10-2) | 1.07 (NS) | 1.43 (3.9·10-2) | 0.91 (NS) | 1.08 (NS) | 0.84 (NS) | 0.80 (NS) | 1.03 (NS) |
Docosatetraenoic acid | 1.18 (9.7·10-2) | 0.73 (NS) | 1.30 (1.2·10-2) | 1.76 (1.7·10-3) | 0.99 (NS) | 1.31 (3.3·10-2) | 0.97 (NS) | 0.81 (8.2·10-2) | 1.10 (NS) |
Docosapentaenoic acid | 1.26 (NS) | 0.75 (NS) | 1.39 (3.4·10-2) | 1.86 (1.7·10-2) | 1.01 (NS) | 1.38 (3.9·10-2) | 1.04 (NS) | 0.80 (NS) | 1.06 (NS) |
Docosahexaenoic acid | 1.09 (NS) | 0.60 (7.8·10-2) | 1.23 (NS) | 1.75 (9.0·10-3) | 0.86 (NS) | 1.24 (NS) | 0.85 (NS) | 0.74 (5.4·10-2) | 1.07 (NS) |
Acyl-carnitines | |||||||||
Acetyl-L-carnitine | 1.40 (1.6·10-2) | 0.88 (NS) | 1.54 (4.5·10-3) | 1.75 (2.0·10-2) | 1.00 (NS) | 1.43 (3.3·10-2) | 1.35 (NS) | 0.96 (NS) | 1.02 (NS) |
Octanoyl-L-carnitine | 1.46 (2.3·10-2) | 0.87 (NS) | 1.62 (1.2·10-2) | 1.50 (NS) | 0.80 (NS) | 1.60 (3.3·10-2) | 1.23 (NS) | 0.77 (NS) | 1.01 (NS) |
Decanoyl-L-carnitine | 1.43 (3.2·10-2) | 0.79 (NS) | 1.61 (1.2·10-2) | 1.51 (NS) | 0.73 (NS) | 1.54 (3.3·10-2) | 1.24 (NS) | 0.78 (NS) | 0.97 (NS) |
Undecanoyl-L-carnitine | 1.20 (1.6·10-2) | 0.96 (NS) | 1.25 (9.7·10-3) | 1.16 (NS) | 0.89 (NS) | 1.23 (3.3·10-2) | 1.15 (NS) | 0.96 (NS) | 1.02 (NS) |
Lauroyl-L-carnitine | 1.44 (1.6·10-2) | 0.79 (NS) | 1.62 (6.0·10-3) | 1.77 (3.6·10-2) | 0.87 (NS) | 1.56 (3.3·10-2) | 1.22 (NS) | 0.73 (8.2·10-2) | 0.94 (NS) |
Myristoyl-L-carnitine | 1.34 (1.6·10-2) | 0.93 (NS) | 1.44 (6.0·10-3) | 1.62 (1.2·10-2) | 1.04 (NS) | 1.39 (3.3·10-2) | 1.24 (NS) | 0.89 (NS) | 1.00 (NS) |
Palmitoyl-L-carnitine | 1.27 (2.2·10-2) | 1.05 (NS) | 1.32 (1.2·10-2) | 1.44 (4.4·10-2) | 1.14 (NS) | 1.32 (3.3·10-2) | 1.18 (NS) | 0.74 (8.2·10-2) | 0.82 (NS) |
Oleoyl-L-carnitine | 1.33 (1.8·10-2) | 0.89 (NS) | 1.45 (9.7·10-3) | 1.58 (8.0·10-2) | 0.97 (NS) | 1.39 (3.3·10-2) | 1.24 (NS) | 0.80 (NS) | 0.89 (NS) |
Linoleoyl-L-carnitine | 1.38 (1.6·10-2) | 1.11 (NS) | 1.43 (9.7·10-3) | 1.36 (NS) | 1.06 (NS) | 1.40 (3.3·10-2) | 1.33 (NS) | 0.54 (1.2·10-3) | 0.57 (1.8·10-3) |
Other metabolites | |||||||||
Citric acid | 0.95 (NS) | 0.35 (5.3·10-2) | 1.16 (NS) | 2.80 (3.6·10-2) | 0.84 (NS) | 0.88 (NS) | 1.11 (NS) | 1.09 (NS) | 0.87 (NS) |
Oxaloacetic acid | 0.97 (NS) | 2.88 (NS) | 0.78 (NS) | 0.41 (7.0·10-2) | 1.50 (NS) | 0.93 (NS) | 1.05 (NS) | 0.84 (NS) | 0.74 (NS) |
Creatine | 1.00 (NS) | 0.59 (NS) | 1.11 (NS) | 1.40 (NS) | 0.74 (NS) | 0.95 (NS) | 1.11 (NS) | 3.30 (1.7·10-9) | 2.84 (3.8·10-8) |
Creatinine | 1.10 (NS) | 1.45 (NS) | 1.04 (NS) | 0.73 (8.0·10-2) | 1.02 (NS) | 1.03 (NS) | 1.26 (NS) | 0.61 (4.9·10-4) | 0.50 (1.8·10-9) |
Pantothenic acid | 1.33 (1.6·10-2) | 1.34 (NS) | 1.32 (1.2·10-2) | 1.23 (NS) | 1.25 (NS) | 1.37 (3.3·10-2) | 1.25 (NS) | 1.07 (NS) | 1.16 (NS) |
Association of fatty acid-related metabolites with biochemical and neuropsychological variables
Fε4- | Mε4- | Fε4+ | Mε4+ | |
---|---|---|---|---|
Biochemical variables | ||||
Glucose | FFAs: C14:0 (0.29), C16:0 (0.33), C16:1 (0.27), C17:0 (0.24), C18:0 (0.19), C18:1 (0.35), C18:2 (0.27), C18:3 (0.37), C20:4 (0.31), C22:4 (0.47), C22:5 (0.28), C22:6 (0.21) ACs: C2 (0.28), C3 (0.19), C8 (0.19), C10 (0.19), C12 (0.24), C14 (0.27), C16 (0.22), C18:1 (0.18) Others: creatinine (-0.19), lactic acid (0.26), pantothenic acid (0.21) | FFAs: C14:0 (0.32), C16:0 (0.41), C17:0 (0.32), C18:0 (0.39), C18:1 (0.30), C18:2 (0.26), C18:3 (0.26), C20:4 (0.35), C22:4 (0.45), C22:5 (0.36), C22:6 (0.26) ACs: C2 (0.23) Others: creatinine (-0.37), lactic acid (0.26), pyruvic acid (0.28) | FFAs: C16:1 (0.43), C18:1 (0.50), C18:3 (0.46) | |
Creatinine | ACs: C2 (0.25), C3 (0.18), C4 (0.28), C11 (0.14), C14 (0.17), C18:2 (0.19) Others: creatine (-0.24), pantothenic acid (0.31) | FFAs: C16:0 (-0.17), C18:0 (-0.19), C18:1 (-0.18), C20:4 (-0.18), C22:4 (-0.25) ACs: C2 (0.25), C3 (0.21), C4 (0.35), C11 (0.18), C14 (0.17) | ACs: C8 (0.33), C10 (0.39), C11 (0.41), C12 (0.36) Others: pantothenic acid (0.24) | FFAs: C18:0 (-0.39) ACs: C3 (0.37), C4 (0.56) |
Cholesterol | FFAs: C22:4 (-0.11) ACs: C1 (-0.16), C2 (-0.15) Others: pantothenic acid (-0.20) | FFAs: C20:4 (0.22), C20:5 (0.19) | FFAs: C20:4 (0.42), C22:4 (0.26) Others: niacinamide (0.33) | FFAs: C17:0 (0.42), C18:2 (0.44) |
LDL-C | FFAs: C16:1 (-0.14), C22:4 (-0.16) Others: pantothenic acid (-0.21) | FFAs: C20:4 (0.21) Others: niacinamide (0.20), creatine (0.20) | FFAs: C20:4 (0.30), Others: niacinamide (0.31) | FFAs: C17:0 (0.46), |
HDL-C | FFAs: C18:1 (0.12), C20:4 (0.15), C22:6 (0.13) ACs: C8 (0.20), C10 (0.21), C11 (0.22), C12 (0.22) | FFAs: C14:0 (0.19) ACs: C3 (-0.18), C18:1 (-0.22) Others: pantothenic acid (-0.21), niacinamide (-0.24) | FFAs: C20:5 (0.34), C22:6 (0.21) Others: creatine (0.33) | Others: creatinine (-0.42), pyruvic acid (-0.44) |
Triglycerides | FFAs: C14:0 (0.16), C16:0 (0.15), C22:4 (0.22) ACs: C3 (0.18), C14 (0.21), C16 (0.24) Others: thiamine (-0.18) | ACs: C16 (-0.11) Others: niacinamide (0.34), pyruvic acid (0.25), citric acid (-0.23) | FFAs: C14:0 (0.38), C16:0 (0.40), C17:0 (0.30), C18:0 (0.34), C18:1 (0.33), C18:2 (0.25), C18:3 (0.28), C20:4 (0.36), C22:4 (0.42), C22:5 (0.30) Others: pyruvic acid (0.32) | FFAs: C14:0 (0.50), C17:0 (0.41), C18:2 (0.37), C18:3 (0.44), C22:5 (0.38) |
Neuropsychological variables | ||||
MMSE | FFAs: C22:5 (0.19) ACs: C8 (0.22), C10 (0.19), C12 (0.23) Others: pantothenic acid (-0.20) | FFAs: C22:4 (-0.43) ACs: C2 (-0.38), C14 (-0.43), C16 (-0.39) Others: creatine (0.54), pyruvic acid (-0.44) | ||
BVRT | Others: pantothenic acid (-0.22) | Others: creatine (0.31) | Others: citric acid (0.72) | |
IST | FFAs: C16:0 (-0.14), C16:1 (-0.16), C18:1 (-0.14), C22:4 (-0.14) | FFAs: C18:3 (0.17), C20:4 (0.24), C22:4 (0.20), C22:5 (0.19), C22:6 (0.19) | FFAs: C22:4 (-0.22) | FFAs: C16:0 (0.44), C18:0 (0.54), C18:1 (0.40), C18:2 (0.37), C18:3 (0.40), C20:5 (0.62), C22:6 (0.66) Others: citric acid (0.43) |
TMTA | ACs: C14 (-0.15), C18:1 (-0.15) | FFAs: C16:1 (0.19), C18:3 (0.23), C20:4 (0.24), C20:5 (0.28), C22:4 (0.19), C22:5 (0.28), C22:6 (0.33) | ACs: C3 (0.31), C4 (0.34), C16 (0.25), C18:1 (0.27) | FFAs: C20:4 (0.71), C22:6 (0.43) Others: niacinamide (0.46) |
TMTB | FFAs: C22:4 (-0.13), C22:5 (-0.11) Others: citric acid (0.15) | Others: niacinamide (-0.22) | FFAs: C16:0 (0.30), C18:0 (0.34), C20:4 (0.24) Others: citric acid (0.29), lactic acid (0.43) | Others: creatinine (-0.58) |