In recent years, there has been an increasing focus on generalized anxiety
disorder (GAD) which is one of the most prevalent mental disorders in general
population. Psychological, genetic, neurobiological, and neurochemical factors
are believed to play role in the etiopathogenesis of GAD. The role of oxidative
stress, as a neurochemical cause, in various anxiety disorders has been studied
in recent years; however, it has not been thoroughly studied in GAD, yet. In this
paper, we aimed to evaluate the serum levels of lipid hydroperoxide (LOOH),
paraoxonase, and arylesterase in GAD patients without any co-morbid psychiatric
disorders and investigate their diagnostic performance. Blood samples were
collected from 40 GAD patients and 40 healthy control subjects to measure their
serum LOOH levels, arylesterase and paraoxonase activities. Obtained results have
been compared between groups and receiver operating characteristic (ROC) curve
has been drawn for diagnostic performance of measured biochemical markers.
Positive and negative predictive values have been estimated where appropriate.
Mean LOOH level of the GAD patients was significantly higher than that of control
subjects (t=-5.49, p<0.001), whereas, mean paraoxonase activity was lower in
these patients (t=3.056, p=0.03). GAD could be predicted for LOOH level over
7.740μmol/l with 92.5% positive predictive value and 92% negative predictive
value. Increased LOOH level and decreased paraoxonase activity of GAD patients
may suggest increased lipid peroxidation and oxidative stress in these patients.
LOOH levels may be a state marker for diagnosing GAD