title: Predictors and clinical significance of progression or regression of asymptomatic carotid stenosis.
abstract: OBJECTIVE
  To determine baseline clinical and ultrasonographic plaque factors predictive of progression or regression of asymptomatic carotid stenosis and the predictive value of changes in stenosis severity on risk of first ipsilateral cerebral or retinal ischemic events (including stroke).
  
  
  METHODS
  A total of 1121 patients with asymptomatic carotid stenosis of 50% to 99% in relation to the bulb diameter (European Carotid Surgery Trial [ECST] method) underwent six monthly clinical assessments and carotid duplexes for up to 8 years (mean follow-up, 4 years). Progression or regression was considered present if there was a change of at least one grade higher or lower, respectively, persisting for at least two consecutive examinations.
  
  
  RESULTS
  Regression occurred in 43 (3.8%), no change in 856 (76.4%), and progression in 222 (19.8%) patients. Younger age, high grades of stenosis, absence of discrete white areas in the plaque, and taking lipid lowering therapy were independent baseline predictors of increased incidence of regression. High serum creatinine, male gender, not taking lipid lowering therapy, low grades of stenosis, and increased plaque area were independent baseline predictors of progression. One hundred and thirty first ipsilateral cerebral or retinal ischemic events, including 59 strokes, occurred. Forty (67.8%) of the strokes occurred in patients whose stenosis was unchanged, 19 (32.2%) in those with progression, and zero in those with regression. For the entire cohort, the 8-year cumulative ipsilateral cerebral ischemic stroke rate was zero in patients with regression, 9% if the stenosis was unchanged, and 16% if there was progression (average annual stroke rates of 0%, 1.1%, and 2.0%, respectively; log-rank, P = .05; relative risk in patients with progression, 1.92; 95% confidence interval, 1.14-3.25). For patients with baseline stenosis 70% to 99% in relation to the distal internal carotid (North American Symptomatic Carotid Endarterectomy Trial [NASCET] method), in the absence of progression (n = 349), the 8-year cumulative ipsilateral cerebral ischemic stroke rate was 12%. In the presence of progression (n = 77), it was 21% (average annual stroke rates of 1.5% and 2.6%, respectively; log-rank, P = .34). Only nine (30%) of the 30 strokes occurred in the progression group.
  
  
  CONCLUSIONS
  Progressive asymptomatic carotid stenosis identified a subgroup with about twice the risk of ipsilateral stroke compared with those without progression. However, the clinical value of screening for progression simply for selecting patients for carotid procedures is limited because of the low frequency of progression and its relatively low associated stroke rate. The cost effectiveness of screening for change in stenosis severity to better direct current optimal medical treatment needs testing.
authors.affiliation: Department of Vascular Surgery, Imperial College, London, United Kingdom.
authors.forename: Stavros K
authors.initials: SK
authors.lastname: Kakkos
authors.affiliation: Department of Vascular Surgery, Imperial College, London, United Kingdom. Electronic address: anicolaides1@gmail.com.
authors.forename: Andrew N
authors.initials: AN
authors.lastname: Nicolaides
authors.affiliation: Vascular Screening and Diagnostic Center, Nicosia, Cyprus.
authors.forename: Ioanna
authors.initials: I
authors.lastname: Charalambous
authors.affiliation: Department of Neurology, St. Mary's Hospital, London, United Kingdom.
authors.forename: Dafydd
authors.initials: D
authors.lastname: Thomas
authors.affiliation: Department of Vascular Surgery, Imperial College, London, United Kingdom.
authors.forename: Argyrios
authors.initials: A
authors.lastname: Giannopoulos
authors.affiliation: Department of Vascular Surgery, Leicester Royal Infirmary, Leicester, United Kingdom.
authors.forename: A Ross
authors.initials: AR
authors.lastname: Naylor
authors.affiliation: Department of Vascular Surgery, Imperial College, London, United Kingdom; Department of Vascular Surgery, Ealing Hospital, London, United Kingdom.
authors.forename: George
authors.initials: G
authors.lastname: Geroulakos
authors.affiliation: School of Public Health and Preventive Medicine, Monash University, Melbourne, Australia; Preventive Health Division of Baker IDI Heart and Diabetes Institute, Melbourne, Australia; Stroke Division of the Florey Institute of Neuroscience and Mental Health, Melbourne, Australia.
authors.forename: Anne L
authors.initials: AL
authors.lastname: Abbott
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D058070:Asymptomatic Diseases; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging; D016893:Carotid Stenosis / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000453:epidemiology; D018450:Disease Progression; D005060:Europe / Q000453:epidemiology; D005260:Female; D006801:Humans; D015994:Incidence; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D058226:Plaque, Atherosclerotic; D011237:Predictive Value of Tests; D011379:Prognosis; D012074:Remission Induction; D012164:Retinal Diseases / Q000453:epidemiology; D012307:Risk Factors; D020521:Stroke / Q000453:epidemiology; D013997:Time Factors; D018616:Ultrasonography, Doppler, Duplex; D014739:Victoria / Q000453:epidemiology