Plasma Lipoprotein (a) levels in patients with untreated essential hypertension

Lipoprotein (a) [Lp (a)] is considered as a risk factor for vascular diseases, especially those associated with renal failure. Adequate studies have not been conducted on the lipoprotein (a) in essential hypertensive patients. There is a controversy on the mechanisms by which Lp (a) is associated with essential hypertension. It is unclear whether Lp (a) contributes to atherogenesis or to thrombogenesis or both. Recent studies suggest that Lp (a) can act as a marker for determining vascular or tissue injury. Reports on Indian population indicate elevated levels of Lp (a), together with other serum lipoproteins emphasizing an important role in Coronary Heart Disease (CHD) and peripheral atherosclerosis. In the present study we aimed to evaluate the relation between plasma levels of Lp (a) and the parameters of the lipid profile in a group of essential hypertensive patients, who are not receiving pharmacological treatment and with no clinical signs of associated pathologies or organ damage. A total of 37 essential hypertensive patients (27 men and 10 women) were compared with 50 controls (32 men and 18 women). It was observed that the hypertensive patients had higher plasma concentrations of Lp (a), Total Cholesterol (TC), Low-Density Lipoprotein-Cholesterol (LDL-C), and Triglycerides (TG) as compared to controls (P< 0.01). Hypertensive patients were also observed to have significantly low levels of High-Density Lipoprotein Cholesterol levels (HDL-C) as compared to controls (P<0.01). Only 14 hypertension patients and 4 controls had plasma concentrations of Lp (a) of over 30 mg/dl. Lp (a) values correlated significantly (P<0.05) with systolic blood pressure (SBP), diastolic blood pressure (DBP) and the main parameters of the lipid profile. We conclude that elevated plasma Lp (a) levels were associated with hypertension and show significant correlation with lipid levels. However higher plasma concentrations of Lp (a), albeit with in the normal range, could be an independent risk factor for atherosclerosis, and could contribute towards increasing the risk for cardiovascular disease in persons with essential hypertension.