Serum Lipid Concentrations in Patients With Comorbid Generalized Anxiety Disorder and Major Depressive Disorder

Levent Sevincok, MD1, Aslihan Buyukozturk, MD2, Ferhan Dereboy, MD3

Objective: To examine the lipid levels in a sample of patients with comorbid generalized anxiety disorder (GAD) and major depressive disorder (MDD).
Method: Serum lipid concentrations were examined in 40 patients with both GAD and MDD, in 27 patients with MDD only, in 26 patients with GAD only, and in 24 healthy control subjects.
Results: All mean serum cholesterol concentrations are presented in Table 1. The mean serum total cholesterol concentration in patients with both GAD and MDD was significantly higher than in MDD-only patients, GAD-only patients, and control subjects. The triglyceride concentration was also significantly higher in patients with both GAD and MDD than in MDD-only  patients, GAD-only patients, and control subjects. Patients with both GAD and MDD had a lower mean high-density lipoprotein cholesterol (HDL-C) concentration than did patients with GAD only and control subjects. The serum concentration of low-density lipoprotein cholesterol (LDL-C) was higher in patients with both GAD and MDD than in patients with MDD only and GAD only and healthy control subjects.
Conclusion: Our findings indicate that the patients with both GAD and MDD have increased serum cholesterol, triglyceride, and LDL-C and reduced HDL-C levels. These patients may have a greater risk of mortality from coronary artery disease (CAD) than do patients with either depression or anxiety disorder.

(Can J Psychiatry 2001;46:68-71)

Key Words: generalized anxiety disorder, major depressive disorder, cholesterol, triglyceride, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol

High serum lipid concentrations are closely associated with stress and anxiety (1,2). Several investigations have demonstrated that both natural and experimentally induced stress result in a significant increase in cholesterol (3,4). Therefore, the presence of anxiety may increase the risk for coronary heart disease. Sympathetic activation in generalized anxiety disorder (GAD) (5) and in panic disorder (PD) (4,6) causes an increase in the activity of lipoprotein lipase through the release of epinephrine and corticosteroids. This hyperactivity in lipoprotein lipase results in an increase in free fatty acids which may be converted into cholesterol. Previous studies also reported an association between low cholesterol levels and major depressive disorder (MDD) (7–11). Maes and others suggested that MDD was accompanied by

Manuscript received January 2000, revised, and accepted June 2000.
1Associate Professor, Department of Psychiatry, Adnan Menderes University Faculty of Medicine, Aydin, Turkey.
2Assistant Professor, Department of Biochemistry, Adnan Menderes University Faculty of Medicine, Aydin, Turkey.
3Professor, Department of Psychiatry, Adnan Menderes University Faculty of Medicine, Aydin, Turkey.
Address for correspondence: Dr L Sevincok, Adnan Menderes University, Tip Fak., Psikiyatri AD, Aydin, Turkey.
e-mail: lsevincok@usa.net

reduced formation of cholesteryl esters and by impaired reverse cholesterol transport (9). Hayward and others (12) and Bajwa and others (13) found that PD patients had significantly higher cholesterol levels compared with MDD patients and healthy control subjects. Bajwa and others also reported that among MDD patients, a history of anxiety disorders (GAD, simple phobia, PD) was associated with a significant elevation of serum cholesterol levels (13). Agargun and others found that PD patients had higher serum cholesterol than did PD patients with comorbid MDD and normal control subjects (14). They concluded that there was an association between low cholesterol levels and the presence of MDD in patients with PD. Kuczmierczyk and colleagues investigated the association between lipid levels and GAD and found that patients with GAD alone had significantly higher serum cholesterol and triglyceride levels than did patients with mixed GAD and MDD (15). In addition, elevated cholesterol, triglyceride, and low-density lipoprotein cholesterol (LDL-C) levels and reduced high-density lipoprotein cholesterol (HDL-C) levels were found in Vietnam veterans with chronic posttraumatic stress disorder (PTSD) (16). The excess lipid mobilization resulting from caloric malnutrition in bulimia nervosa (BN) (17) and anorexia nervosa (AN) patients (18) has been demonstrated to increase the plasma levels of free fatty acids.

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