The Keith-Wagener-Barker and Mitchell-Wong grading systems for hypertensive retinopathy: association with target organ damage in individuals below 55 years.
BACKGROUND
The usefulness of the hypertensive retinopathy classification by Keith-Wagener-Barker (KWB) in clinical practice remains controversial. The simplified Mitchell-Wong grading, combining the two initial KWB' grades in one stage, is proposed as an alternative method; both systems are poorly validated regarding their association with target organ damage.


OBJECTIVE
In a population free of cardiovascular disease and diabetes, we aimed to investigate the interobserver and intraobserver agreement of both grading systems, their association with aortic stiffness, carotid hypertrophy or plaques and the role of age and sex on this association.


METHODS
Digital retinal images were obtained and graded - according to both classifications - by two independent and blinded observers; aortic stiffness (carotid-femoral pulse wave velocity, m/s) and common carotid hypertrophy (cross-sectional area, mm) or plaques were assessed by tonometry and ultrasound, respectively.


RESULTS
From the gradable retinal photos obtained by 200 eyes of 107 consecutive patients (age: 54 ± 13 years, 51% men, 79% hypertensive patients) and after adjustments for confounders, the intraobserver and interobserver level of agreement was as following: KWB 88/64% and Mitchell-Wong 91/71%, respectively; exclusively in younger, not older, individuals aortic stiffness, carotid hypertrophy, but not plaques, were significantly associated with both systems, independently from confounders; no differences regarding target organ damage were found between stages 1 and 2 of KWB.


CONCLUSIONS
Detecting early signs of hypertensive retinopathy may be of value in young individuals; the Mitchell-Wong seems preferable to the KWB classification system only for reasons of simplifying clinical practice.
aHypertension Unit and Cardiovascular Research Laboratory, First Department of Propaedeutic Internal Medicine, Laiko Hospital bSecond Department of Ophthalmology, Attikon University Hospital cBiomedical Engineering Unit, First Department of Cardiology, Hippokration Hospital, Medical School, National and Kapodistrian University of Athens, Athens, Greece.
Evaggelia K
EK
Aissopou
Miltiadis
M
Papathanassiou
Efthimia G
EG
Nasothimiou
George D
GD
Konstantonis
Nikolaos
N
Tentolouris
Panagiotis G
PG
Theodossiadis
Theodore G
TG
Papaioannou
Petros P
PP
Sfikakis
Athanasios D
AD
Protogerou
D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D058437:Hypertensive Retinopathy / Q000145:classification* / Q000175:diagnosis / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D063177:Pulse Wave Analysis; D012160:Retina / Q000503:physiopathology*; D059289:Vascular Stiffness / Q000502:physiology*