title: Association of Subjective and Objective Sleep Duration as well as Sleep Quality with Non-Invasive Markers of Sub-Clinical Cardiovascular Disease (CVD): A Systematic Review.
abstract: OBJECTIVE
  Abnormal daily sleep duration and quality have been linked to hypertension, diabetes, stroke, and overall cardiovascular disease (CVD) morbidity& mortality. However, the relationship between daily sleep duration and quality with subclinical measures of CVD remains less well studied. This systematic review evaluated how daily sleep duration and quality affect burden of subclinical CVD in subjects free of symptomatic CVD.
  
  
  METHODS
  Literature search was done via MEDLINE, EMBASE, Web of Science until June 2016 and 32 studies met the inclusion criteria. Sleep duration and quality were measured either via subjective methods, as self-reported questionnaires or Pittsburg Sleep Quality Index (PSQI) or via objective methods, as actigraphy or polysomnography or by both. Among subclinical CVD measures, coronary artery calcium (CAC) was measured by electron beam computed tomography, Carotid intima-media thickness (CIMT) measured by high-resolution B-mode ultrasound on carotid arteries, endothelial/microvascular function measured by flow mediated dilation (FMD) or peripheral arterial tone (PAT) or iontophoresis or nailfold capillaroscopy, and arterial stiffness measured by pulse wave velocity (PWV) or ankle brachial index (ABI).
  
  
  RESULTS
  Subjective short sleep duration was associated with CAC and CIMT, but variably associated with endothelial dysfunction (ED) and arterial stiffness; however, subjective long sleep duration was associated with CAC, CIMT and arterial stiffness, but variably associated with ED. Objective short sleep duration was positively associated with CIMT and variably with CAC but not associated with ED. Objective long sleep duration was variably associated with CAC and CIMT but not associated with ED. Poor subjective sleep quality was significantly associated with ED and arterial stiffness but variably associated with CAC and CIMT. Poor objective sleep quality was significantly associated with CIMT, and ED but variably associated with CAC.
  
  
  CONCLUSIONS
  Overall, our review provided mixed results, which is generally in line with published literature, with most of the studies showing a significant relationship with subclinical CVD, but only some studies failed to demonstrate such an association. Although such mechanistic relationship needs further evaluation in order to determine appropriate screening strategies in vulnerable populations, this review strongly suggested the existence of a relationship between abnormal sleep duration and quality with increased subclinical CVD burden.
authors.affiliation: Center for Healthcare Advancement & Outcomes, Baptist Health South Florida.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Aziz
authors.forename: Shozab S
authors.initials: SS
authors.lastname: Ali
authors.forename: Sankalp
authors.initials: S
authors.lastname: Das
authors.forename: Adnan
authors.initials: A
authors.lastname: Younus
authors.forename: Rehan
authors.initials: R
authors.lastname: Malik
authors.forename: Muhammad A
authors.initials: MA
authors.lastname: Latif
authors.forename: Choudhry
authors.initials: C
authors.lastname: Humayun
authors.forename: Dixitha
authors.initials: D
authors.lastname: Anugula
authors.forename: Ghulam
authors.initials: G
authors.lastname: Abbas
authors.forename: Joseph
authors.initials: J
authors.lastname: Salami
authors.forename: Javier Valero
authors.initials: JV
authors.lastname: Elizondo
authors.forename: Emir
authors.initials: E
authors.lastname: Veledar
authors.forename: Khurram
authors.initials: K
authors.lastname: Nasir
mesh_terms: D015415:Biomarkers / Q000032:analysis*; D002318:Cardiovascular Diseases / Q000503:physiopathology*; D006801:Humans; D063177:Pulse Wave Analysis / Q000379:methods*; D012890:Sleep / Q000502:physiology*
chemical_list: D015415:Biomarkers