Metabolic syndrome and target organ damage in untreated essential hypertensives

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

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.

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.

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.

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.