Table 2:
Spearman Correlation Coefficients (ρ) between all Sphingolipid species and PHQ9/PCL-M scores.
| Spearman’s (ρ) | PTSD (PCL-M) | PHQ9 (PHQ9) | Spearman’s (ρ) | PTSD (PCL-M) | PHQ9 (PHQ9) |
|---|---|---|---|---|---|
| Meibum | Tear | ||||
| Total SPL pmole | −0.23 | −0.18 | −0.15 | −0.13 | |
| Total Cer mol% | −0.26 | −0.27 | −0.06 | −0.05 | |
| Total Cer pmol | −0.41** | −0.38** | −0.13 | −0.14 | |
| Cer 14:0 mol% | −0.28 | −0.18 | −0.08 | −0.07 | |
| Cer 14:0 pmol | −0.37** | −0.26 | −0.13 | −0.12 | |
| Cer 16:0 mol% | −0.39** | −0.3* | −0.12 | −0.10 | |
| Cer 16:0 pmol | −0.35* | −0.29* | −0.15 | −0.14 | |
| Cer 18:0 mol% | 0 | −0.12 | −0.03 | −0.05 | |
| Cer 18:0 pmol | −0.29* | −0.39** | −0.14 | −0.13 | |
| Cer 18:1 mol% | −0.26 | −0.16 | −0.18 | −0.16 | |
| Cer 18:1 pmol | −0.33* | −0.26 | −0.16 | −0.16 | |
| Cer 20:0 mol% | 0 | −0.12 | 0.02 | −0.08 | |
| Cer 20:0 pmol | −0.22 | −0.35* | −0.11 | −0.12 | |
| Cer 22:0 mol% | −0.12 | −0.2 | 0.07 | 0.01 | |
| Cer 22:0 pmol | −0.33* | −0.37** | −0.10 | −0.09 | |
| Cer 24:0 mol% | −0.32 | −0.3 | 0.01 | 0.02 | |
| Cer 24:0 pmol | −0.40** | −0.34** | −0.12 | −0.10 | |
| Cer 24:1 mol% | −0.3* | −0.13 | −0.01 | −0.04 | |
| Cer 24:1 pmol | −0.30* | −0.20 | −0.11 | −0.12 | |
| Cer 26:0 mol% | −0.30* | −0.27 | 0.15 | 0.25 | |
| Cer 26:0 pmol | −0.38** | −0.27 | −0.07 | −0.05 | |
| Cer 26:1 mol% | −0.34* | −0.38** | 0.08 | 0.14 | |
| Cer 26:1 pmol | −0.41** | −0.43** | −0.10 | −0.08 | |
| Total Hex-Cer mol% | −0.17 | −0.32* | −0.09 | 0.06 | |
| Total Hex-Cer pmol | −0.29* | −0.35** | −0.15 | −0.07 | |
| Hex-Cer 14:0 mol% | 0.09 | −0.19 | −0.06 | −0.15 | |
| Hex-Cer 14:0 pmol | −0.14 | −0.28 | −0.13 | −0.19 | |
| Hex-Cer 16:0 mol% | −0.12 | −0.24 | −0.05 | 0.01 | |
| Hex-Cer 16:0 pmol | −0.28* | −0.29* | −0.12 | −0.05 | |
| Hex-Cer 18:0 mol% | 0.03 | −0.17 | −0.03 | 0.10 | |
| Hex-Cer 18:0 pmol | −0.24 | −0.35** | −0.09 | −0.02 | |
| Hex-Cer 18:1 mol% | −0.04 | −0.19 | −0.12 | −0.04 | |
| Hex-Cer 18:1 pmol | −0.07 | −0.21 | −0.16 | −0.10 | |
| Hex-Cer 20:0 mol% | −0.04 | −0.24 | 0.04 | 0.17 | |
| Hex-Cer 20:0 pmol | −0.25 | −0.44*** | −0.04 | 0.02 | |
| Hex-Cer 22:0 mol% | −0.02 | −0.1 | −0.05 | 0.09 | |
| Hex-Cer 22:0 pmol | −0.19 | −0.18 | −0.11 | −0.02 | |
| Hex-Cer 24:0 mol% | −0.19 | −0.12 | −0.07 | 0.11 | |
| Hex-Cer 24:0 pmol | −0.23 | −0.18 | −0.15 | −0.03 | |
| Hex-Cer 24:1 mol% | −0.36** | −0.31* | −0.22 | −0.01 | |
| Hex-Cer 24:1 pmol | −0.38** | −0.37** | −0.17 | −0.06 | |
| Hex-Cer 26:0 mol% | −0.17 | −0.28 | −0.08 | −0.01 | |
| Hex-Cer 26:0 pmol | −0.45*** | −0.57*** | −0.11 | −0.13 | |
| Hex-Cer 26:1 mol% | −0.12 | −0.22 | 0.05 | 0.15 | |
| Hex-Cer 26:1 pmol | −0.3* | −0.37** | −0.02 | 0.02 | |
| SA mole% | 0.21 | 0.17 | NA | NA | |
| SA pmole | 0.01 | 0.03 | NA | NA | |
| S1P mole% | NA | NA | 0.13 | 0.17 | |
| S1P pmol | NA | NA | 0.08 | 0.10 | |
| Total SM mol% | 0.15 | 0.28 | −0.12 | −0.08 | |
| Total SM pmole | −0.17 | −0.11 | −0.16 | −0.15 | |
| SM 14:0 mol% | 0.02 | −0.07 | −0.15 | −0.31* | |
| SM 14:0 pmol | −0.15 | −0.16 | −0.17 | −0.19 | |
| SM 16:0 mol% | 0.18 | 0.22 | −0.16 | −0.24 | |
| SM 16:0 pmol | −0.15 | −0.12 | −0.17 | −0.17 | |
| SM 18:0 mol% | 0.1 | 0.17 | 0.06 | −0.15 | |
| SM 18:0 pmol | −0.14 | −0.08 | −0.14 | −0.15 | |
| SM 18:1 mol% | −0.01 | −0.1 | −0.12 | −0.22 | |
| SM 18:1 pmol | −0.14 | −0.13 | −0.13 | −0.17 | |
| SM 20:0 mol% | 0.04 | 0.15 | 0.12 | −0.07 | |
| SM 20:0 pmol | −0.15 | −0.08 | −0.14 | −0.16 | |
| SM 22:0 mol% | −0.04 | 0.14 | 0.09 | 0.11 | |
| SM 22:0 pmol | −0.16 | −0.08 | −0.14 | −0.13 | |
| SM 24:0 mol% | −0.14 | 0.1 | 0.00 | 0.16 | |
| SM 24:0 pmol | −0.20 | −0.11 | −0.16 | −0.11 | |
| SM 24:1 mol% | 0.04 | 0.11 | −0.07 | −0.12 | |
| SM 24:1 pmol | −0.15 | −0.1 | −0.16 | −0.16 | |
| SM 26:0 mol% | −0.2 | −0.02 | 0.07 | 0.00 | |
| SM 26:0 pmol | −0.27 | −0.14 | −0.08 | −0.07 | |
| SM 26:1 mol% | −0.07 | 0.12 | −0.03 | 0.00 | |
| SM 26:1 pmol | −0.20 | −0.12 | −0.17 | −0.14 | |
| SO mole% | 0.20 | 0.08 | 0.22 | 0.22 | |
| SO pmole | 0.04 | −0.12 | 0.04 | 0.03 | |
Statistically significant difference at
*
p-values <0.05
**
p-value <0.01
***
p-value <0.001.
Abbreviations: Sphingolipids (SPL), Ceramides (Cer), Hexosyl ceramide (Hex-cer), Sphingomyelin (SM), Sphingosine 1-phosphate (S1P), Sphinganine (Sa), Sphingosine (SO), Pico mole (pmole), Mole (mol), Post-traumatic stress disorder (PTSD), Patient Health Questionnaire-9 (PHQ-9), PTSD Checklist–Military Version (PCL-M), Not analysed (NA)