Sleep duration and insomnia in the elderly: associations with blood pressure variability and carotid artery...

Recent studies have shown that short and long sleep durations and insomnia are associated with increased home-measured blood pressure (BP) variability, which in turn has a relationship with arterial stiffness. However, the determinants for visit-to-visit systolic blood pressure (SBP) variability have rarely been investigated in relation to sleep duration, insomnia, and carotid arterial stiffness.

The subjects were 201 elderly individuals (79.9±6.4 years old) with one or more cardiovascular risks. Based on 12 visits, visit-to-visit BP variability (expressed as a coefficient of variation [CV]) and δ (maximum - minimum) BP were measured. Self-reported sleep duration and insomnia questionnaires were used to classify the patients according to sleep duration period and insomnia status.

After multivariable adjustment, long sleep duration (≥ 9 hours per night) had significant positive associations with SBP δ (P < 0.05), while persistent insomnia had significant positive associations with SBP CV (P < 0.05) and δ (P < 0.01). Additionally, significant interactions were found in terms of long sleep duration by carotid artery stiffness parameter β (P < 0.05), persistent insomnia by intima-media thickness (P < 0.01), and persistent insomnia by stiffness parameter β (P < 0.05) for SBP δ.

In elderly patients at high risk for cardiovascular disease, long sleep duration as well as persistent insomnia were significantly associated with higher visit-to-visit BP variability. Long sleep duration and persistent insomnia each had synergetic interactions with carotid artery stiffness and with visit-to-visit BP variability.