Serum uric acid in hypertensive patients with and without peripheral arterial disease.
BACKGROUND
Uric acid is frequently elevated in hypertension. In addition to renal and metabolic disturbances, lower limb ischemia might contribute to hyperuricemia among hypertensives complicated by peripheral arterial disease (PAD).


OBJECTIVE
To test the hypothesis that uric acid status is related to lower limb function in hypertensives with PAD.


METHODS
Serum and 24-h urine uric acid levels and other risk factors were examined in 145 hypertensives free of PAD and 166 hypertensives with PAD. Ankle/brachial index (ABI) and absolute claudication distance (in PAD) on a treadmill test (ACD) were assessed.


RESULTS
In multiple regression analysis for serum uric acid in the total group, PAD emerged as an independent determinant (P=0.03) next to age (P=0.005), triglycerides (P=0.04), and insulin (P=0.02). Serum uric acid concentrations were higher in hypertensives with PAD (404+/-101 vs. 347+/-80 micromol/l, P<0.001) independent of components of the metabolic syndrome (body mass index, triglycerides, insulin) and of age, gender, diabetes mellitus, pulse pressure, cholesterol, C-reactive protein, and treatment. After adjustment for kidney function by uric acid/creatinine ratio, values remained higher in hypertensives with PAD (P=0.01). Uric acid excretion was higher in the PAD group (P<0.001), whereas uric acid clearance was comparable between both groups. In multiple regression analysis for ACD (357+/-183 m) in the PAD group, serum uric acid (P=0.02), C-reactive protein (P<0.0001), age (P=0.02), and smoking (P=0.004) were independently associated. ABI (0.62+/-0.17) was not related to uric acid in PAD patients.


CONCLUSIONS
Hyperuricemia is more pronounced in hypertensives complicated by PAD and is associated with worse functional status of the peripheral circulation.
Department of Clinical Chemistry, AZ St-Jan AV Hospital, Ruddershove 10, B-8000 Brugge, Belgium. michel.langlois@azbrugge.be
Michel
M
Langlois
Dirk
D
De Bacquer
Daniel
D
Duprez
Marc
M
De Buyzere
Joris
J
Delanghe
Victor
V
Blaton
D000368:Aged; D001530:Belgium / Q000453:epidemiology; D015415:Biomarkers / Q000097:blood / Q000652:urine; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure / Q000502:physiology; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000378:metabolism; D008076:Cholesterol, HDL / Q000378:metabolism; D003404:Creatinine / Q000097:blood; D005080:Exercise Test; D005215:Fasting / Q000378:metabolism; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood* / Q000453:epidemiology; D007328:Insulin / Q000097:blood; D007383:Intermittent Claudication / Q000097:blood / Q000453:epidemiology; D035002:Lower Extremity / Q000098:blood supply; D008297:Male; D008875:Middle Aged; D016491:Peripheral Vascular Diseases / Q000097:blood* / Q000453:epidemiology; D012307:Risk Factors; D013223:Statistics as Topic; D014280:Triglycerides / Q000378:metabolism; D014527:Uric Acid / Q000097:blood* / Q000652:urine
D015415:Biomarkers; D001786:Blood Glucose; D008076:Cholesterol, HDL; D007328:Insulin; D014280:Triglycerides; D014527:Uric Acid; D002097:C-Reactive Protein; D003404:Creatinine