Plasma lipoproteins in posttraumatic stress disorder patients compared to healthy controls and their associations with the HPA- and HPT-axis.

BACKGROUND

Based on studies among primarily male veteran subjects, lipoproteins are thought to mediate the association of posttraumatic stress disorder (PTSD) with cardiovascular disease (CVD). However, recent civilian studies with female samples or samples with both sexes represented provide little evidence for this association. Gender, diet and sex-specific effects of stress hormones on lipoproteins may explain this dissociation in findings.

METHOD

Cross-sectional analysis of plasma concentrations of total cholesterol (TC), low-density lipoprotein (LDL), high-density lipoprotein (HDL) and triglycerides (TG) in a male and female sample of 49 PTSD-patients due to civilian trauma and 45 healthy controls. Second, we related these lipoproteins to several stress hormones (prolactin, cortisol, DHEA(S), TSH, T4).

RESULTS

Patients showed lower LDL (p=0.033) and LDL:HDL ratio (p=0.038) compared to controls, also when adjusting for diet. Sex influenced the effect of having PTSD on LDL with only male patients having lower values than male controls (p=0.012). All stress hormones were associated with several lipoproteins, mostly in a sex-dependent manner. For LDL, a significant sex-by-cortisol effect (p<0.001), having PTSD-by-sex-by-DHEA (p<0.001), having PTSD-by-sex-by-DHEAS (p=0.016) and having PTSD-by-sex-by-prolactin (p=0.003) was found.

CONCLUSION

In this male and female civilian sample we found a somewhat more favorable lipoprotein profile in PTSD-patients in contrast to evidence from strictly male veteran samples exhibiting a less favorable lipoprotein profile. Male patients did not exhibit a worse lipoprotein profile than female patients and therefore gender cannot explain the contradiction in evidence. Additionally, we found that PTSD-related stress hormones are associated with lipoproteins levels in patients in a sex-specific manner. Specific configurations of stress hormones may contribute to CVD in male patients or protect in female patients. Further research on these configurations could indicate which PTSD-patients are especially at risk for CVD and which are not. This could guide future precision medicine efforts to prevent and treat the still growing burden of CVD morbidity and mortality in PTSD.