PubMed1994
BACKGROUND: A positive correlation of arterial hypertension (AH) to atherosclerosis and of AH to cerebral stroke is widely accepted, while the relationship between AH and carotid occlusive disease (COD) is not yet clear. PURPOSE: To assess the correlation of AH to COD in a resident population screened during the OPI (Obiettivo Prevenzione Ictus) program. METHODS: The goals of OPI program are to assess prevalence of COD among the population resident in the USSL (Sanitary District) n. 69 Lombardia (Parabiago-Italy), aged 45 to 75; to administer a therapeutic protocol; and to carry on a long-term follow-up of people treated for risk of stroke from COD. Data reported herein were recorded from the first 16,379 subjects out of 24,436 enrolled in the OPI program and classified according to blood pressure and degree of COD (preliminary report). All were investigated by physical examination and CW Doppler ultrasound; subjects suspected to harbor COD of any entity underwent a second physical examination and color coded echoflow imaging of extracranial carotid arteries, to assess the degree of COD. Statistical analysis has been performed through Fisher's exact test and chi 2 test, and results were assumed as significant for a p value of less than 5 x 10(-2). RESULTS: Among 7,800 males and 8,779 females, some 8,428 (51.45%) people were shown to be hypertensive: 2,800 of them were classified as borderline (e.g.: systolic pressure of 141-160 mmHg and diastolic < 90 mmHg). As many as 538 COD were observed in 404 subjects. Among the 7,951 normotensive people as many as 109 COD (20.3%) were identified in 90 subjects (1.12%); among hypertensive people, 314 (3.72%) were affected with 429 (79.7%) COD (p < 10(-6)): COD prevalence among borderline hypertensive subjects was double than among normotensive (p = 1.3 x 10(-6)). Unilateral as well as bilateral CODs were more frequent among hypertensive people (p between 3.1 x 10(-2) and < 10(-6) according to the degree of stenosis). Forty-five (50%) among 90 normotensive people affected with COD showed unilateral stenosis < 50%, but only 19 (14.2%) among 134 affected with bilateral lesions were normotensive, and 81.6% of these lesions were < 50%. Among 230 lesions in 115 hypertensive people with bilateral COD, 137 (59.5%) were < 50%, 63 (27.4%) between 50-70%, 19 (8.3%) > 70%, and 11 (4.8%) occlusions. CONCLUSIONS: COD is more frequent among hypertensive than normotensive people (odds ratio = 3.38; p < 10(-6)). Severity of COD is higher in hypertensive subjects (odds ratio = 3.79; p < 10(-6)). Isolated systolic hypertension is more frequently associated to COD than systolic-diastolic hypertension (odds ratio = 2.26; p < 10(-6)). Among people with isolated systolic hypertension, diastolic values of less than 75 mmHg do not increase the risk of COD. As COD prevalence is concerned, the 1,494 subjects with effective drug control of hypertension behaved as like as people with isolated systolic hypertension: in particular, the risk of COD was 7.59 times as high as for normotensive people.