Metabolic syndrome and target organ damage in untreated essential hypertensives

Abstract

Background: The prevalence and the relationship between metabolic syndrome, and target organ damage (TOD) in essential hypertensive patients has not been fully explored to date.

Objective: To investigate the association between metabolic syndrome, as defined by the ATP III report, and cardiac and extracardiac TOD, as defined by the 2003 ESH-ESC guidelines for management of hypertension, in a large population of never-treated essential hypertensives.

Methods: A total of 447 grade 1 and 2 hypertensive patients (mean age 46 +/- 12 years) who were attending a hypertension hospital outpatient clinic for the first time underwent the following procedures: (i) physical examination and repeated clinic blood pressure measurements; (ii) routine examinations; (iii) 24-h urine collection for microalbuminuria; (iv) 24-h ambulatory blood pressure monitoring; (v) echocardiography; and (vi) carotid ultrasonography. Metabolic syndrome was defined as involving at least three of the following alterations: increased waist circumference, increased triglycerides, decreased high-density lipoprotein cholesterol, increased blood pressure, or high fasting glucose. Left ventricular hypertrophy (LVH) was defined according to two different criteria: (i) 125 g/m in men and 110 g/m in women; (ii) 51 g/h in men and 47 g/h in women.

Results: The 135 patients with metabolic syndrome (group I) were similar for age, sex distribution, known duration of hypertension and average 24-h, daytime and night-time ambulatory blood pressure to the 312 patients without it (group II). The prevalence of altered left ventricular patterns (LVH and left ventricular concentric remodelling) was significantly higher in group I (criterion a = 30%, criterion b = 42%) than in group II (criterion a = 23%, criterion b = 30%, P < 0.05 and P < 0.01, respectively). A greater urinary albumin excretion (17 +/- 35 versus 11 +/- 23 mg/24 h, P = 0.04) was also found in group I compared to group II. There were no significant differences between the two groups in the prevalence of carotid intima-media thickening and plaques.

Conclusions: These results from a representative sample of untreated middle-aged hypertensives show that: (i) the metabolic syndrome is highly prevalent in this setting and (ii) despite similar ambulatory blood pressure values, patients with metabolic syndrome have a more pronounced cardiac and extracardiac involvement than those without it.