Background: We aimed to investigate differences in circadian autonomic changes in patients suffering from hyperlipidemia with and without erectile dysfunction and compared results to control cases.
Materials and methods: A total of 77 patients (age range: 24-74, mean age: 45.3 ± 9.3) with uncontrolled hyperlipidemia (total cholesterol >200 mg/dL and/or LDL >160 mg/dL despite a regular diet) were enrolled into the study. These patients were divided into two groups according to their International Index of Erectile Function (IIEF-EF) scores as having erectile dysfunction (IIEF-EF < 26) (Group 1) or as having normal erectile function (IIEF-EF ≥ 26) (Group 2). In addition, the control group comprised 44 healthy men (age range: 20-57, mean age: 44.0 ± 10.8) (Group 3). Heart rate variability parameters obtained by 24-h Holter monitoring were utilized for the indirect evaluation of autonomic function.
Results: There were statistically significant differences between the groups with respect to daytime and nocturnal autonomic activity (p < 0.005). Moreover, Group 1 had lower nocturnal parasympathetic and higher nocturnal sympathetic activity compared to the other groups (for nocturnal HFn p(1-2) < 0.001; p(1-3) < 0.001; p(2-3) > 0.05; for nocturnal LFn p(1-2) < 0.001; p(1-3) < 0.001; p(2-3) > 0.05).
Conclusion: We concluded that hyperlipidemia results in deterioration of autonomic circadian rhythm. Hyperlipidemic patients with erectile dysfunction had diminished nocturnal parasympathetic activities.