Prevalence and risk factors of PAD among patients with elevated ABI.
OBJECTIVE
To assess the prevalence and clinical significance of elevated ankle-brachial index (ABI) in patients referred to vascular consultation.


METHODS
Retrospective clinical study.


METHODS
In 1,762 patients referred with a suspicion of peripheral arterial disease (PAD), ABI and toe brachial index (TBI) were measured by photoplethysmography. ABI>/=1.3 was considered falsely elevated and TBI<0.60 was the diagnostic criterion for PAD.


RESULTS
The prevalence of elevated ABI was 8.4% and that of PAD among these patients 62.2%. PAD was significantly more prevalent among subjects with severe symptoms (rest pain, ulcers or gangrene) than in those with intermittent claudication (83.8% and 45.3%, respectively, p<0.001). The risk of PAD diagnosis was ten-fold (OR 10.31, 95% CI 2.07-51.30) among those with chronic renal failure, five-fold among patients with a history of smoking (OR 5.63, 95% CI 1.22-26.00) and over three-fold (OR 3.44, 95% CI 1.46-8.12) among those with coronary heart disease. The specificities of elevated ABI threshold levels (1.3, 1.4 and 1.5) in identifying PAD were 86%, 94% and 96%, respectively, the sensitivities being 44%, 38% and 36%, respectively.


CONCLUSIONS
The prevalence of elevated ABI in patients referred to vascular consultation is 8.4% and that of PAD among these 62.2%. PAD is significantly more probable among those with chronic renal failure, a history of smoking and coronary heart disease. Furthermore, the specificity of elevated ABI (>/=1.3) in recognizing PAD is good, whereas the sensitivity is only satisfactory.
Suominen
V
V
Department of Surgery, Division of Vascular Surgery, Tampere University Hospital, Tampere, Finland. velipekka.suominen@pshp.fi
Rantanen
T
T
Venermo
M
M
Saarinen
J
J
Salenius
J
J
D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D000842:Ankle / Q000098:blood supply*; D001794:Blood Pressure; D001916:Brachial Artery / Q000503:physiopathology*; D003327:Coronary Disease / Q000150:complications / Q000503:physiopathology; D005121:Extremities / Q000098:blood supply; D005260:Female; D005387:Finland / Q000453:epidemiology; D006801:Humans; D007511:Ischemia / Q000150:complications / Q000503:physiopathology; D007676:Kidney Failure, Chronic / Q000150:complications / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D010044:Outpatient Clinics, Hospital; D016491:Peripheral Vascular Diseases / Q000453:epidemiology / Q000209:etiology* / Q000503:physiopathology*; D017156:Photoplethysmography; D011237:Predictive Value of Tests; D015995:Prevalence; D012017:Referral and Consultation; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012680:Sensitivity and Specificity; D012907:Smoking / Q000009:adverse effects