We examined the effects of psychological stress on plasma lipid, lipoprotein, and apolipoprotein levels in three related studies. In the first study, tax accountants (N = 20) and a comparable control group (N = 20) were assessed during and after the tax season. In the second and third studies, first-year medical students (N = 24 and N =16) were assessed at midsemester and immediately before the examinations. Across studies, the stressors induced significant psychological distress. There were no corresponding changes in lipid and lipoprotein levels. Mean stress-induced change in total cholesterol level was -0.04 mmol/L ( — 1.6 mg/dL) (95% confidence interval, —0.23 to 0.16 mmol/L [ — 9 to 6 mg/dL]) for the accountants and 0 mmol/L (0 mg/dL) (95% confidence interval, — 0.16 to 0.21 mmol/L —6 to 8 mg/dL]) and 0.10 mmol/L (4 mg/dL) (95% confidence interval, —0.18 to 0.39 mmol/L [—7 to 15 mg/dL]) for medical students in the second and third studies, respectively. In all studies, change in total cholesterol level correlated with change in total serum protein levels (r=.42 to.60). These results suggest that commonly occurring stressful situations do not produce significant changes in plasma lipid and lipoprotein levels.
(Arch Intern Med. 1991;151:2172-2179)