Comparison of the differences in circadian autonomic function in hyperlipidemic men with and without erectile...

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.

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.

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).

We concluded that hyperlipidemia results in deterioration of autonomic circadian rhythm. Hyperlipidemic patients with erectile dysfunction had diminished nocturnal parasympathetic activities.