M.Sc Thesis

M.Sc StudentHerkon Ora
SubjectCharacterization of Rpn13-Proteasome Interaction
DepartmentDepartment of Medicine
Supervisor DR. Ariel Stanhill
Full Thesis textFull thesis text - English Version


Study objectives: Insomnia is associated with cardiovascular morbidity. However, about 15% of the patients who complain of insomnia may have sleep state misperception (SSM). Endothelial function is a predictor of ischemic heart disease.  We studied the hypothesis that objective insomnia but not SSM leads to overnight deterioration of endothelial function.
: Blinded comparative study.
: A tertiary university hospital's sleep lab. Patients:  29 patients complaining of insomnia (17 with objective insomnia and 12 with SSM).
Measurements and results
: All participants underwent evening and morning assessment of blood pressure, heart rate and endothelial function (reactive hyperemia test, EndoPAT, Itamar-Medical), full night in lab PSG, and morning urinary catecholamine levels assessment. The insomnia group had a total sleep time of 292±64 min compared to 328±66 min of the SSM group. The subjective sleep time was 275±85 min in the insomnia group, compared to 162±106min in the SSM group (p<0.005). While in the insomnia group the endothelial function deteriorated during the night (-0.24±0.48), in the SSM group it improved during the night (0.25±0.49, p<0.05). Urinary Dopamine /Creatinine levels for the insomnia and SSM groups were 199.8±55.4 vs 164.08±33.26 respectively, p<0.05.

Conclusions: In patients with objective insomnia endothelial function deteriorates during the night and their morning urinary dopamine levels are increased compared to patients with insomnia complaints but substantially better objective sleep, in whom endothelial function improved over the course of the night.  These results suggest that patients with objective insomnia are at greater risk for cardiovascular complications compared to sleep state misperception patients.