Characterization of insomnia in patients with essential hypertension.

Insomnia may increase risk of cardiovascular events. There is little data available reporting the prevalence and clinical relevance of insomnia in patients with essential hypertension. Therefore, the aim of the study was to investigate the relationship between insomnia and different clinical and biochemical parameters in essential hypertension patients. Four hundred and thirty-two patients (mean age 47+/-13 years; 253 male, 179 female) with essential hypertension were screened for insomnia using the athens Insomnia Scale (AIS). Several variables including age, sex, known duration of hypertension, body mass index, creatinine, left ventricular mass index, coexisting disorders, smoking status and alcohol use were analysed. Twenty-four-hour ambulatory blood pressure measurements (ABPM) were performed. Among patients included in the study, 207 subjects (mean age: 49+/-13 years; 47.9%) had an AIS score of 15 or higher and were identified as insomniacs. Insomnia was more frequent in women than in men (60.9% vs 38.7%, p<0.001) and was reported more frequently in patients with coronary artery disease. Subjects with insomnia were older and had longer duration of hypertension. There were no differences between insomniacs and non-insomniacs in ABPM parameters. A relationship was found between the number of antihypertensive drugs and insomnia frequency. There were correlation between AIS score and age (r=0.21; p<0.001) and duration of hypertension (r=0.22; p<0.001). In the sub-group of untreated essential hypertension patients, there were negative correlations between AIS score and night fall in systolic and diastolic blood pressure. Our results showed that insomnia is common in patients with essential hypertension and indicate an association between insomnia and gender, known duration of hypertension and number of hypertensive drugs taken. Untreated essential hypertension insomniacs were characterized by less pronounced nocturnal fall in both systolic and diastolic blood pressure compared with non-insomniacs.