Dyslipoproteinemic changes in borderline hypertension.

Abstract

The present study examined plasma lipoprotein, lipoprotein lipase, hepatic lipase, and insulin levels in men with borderline hypertension (diastolic blood pressure 85 to 94 mm Hg) compared with age-matched normotensive control subjects (diastolic blood pressure less than or equal to 80 mmHg, n=75+75). High-density lipoprotein (HDL) subclasses were determinea in a subset (n=45+45). While total and low-density lipoprotein cholesterol levels were similar, levels of very-low-density lipoprotein (VLDL) 3 It has been suggested that insulin resistance with ensuing hyperinsulinemia could be the common link and perhaps even represent the underlying pathogenic mechanism. 4 Insulin stimulates the hepatic secretion of verylow-density lipoprotein (VLDL) and has been implicated in the activation of lipoprotein lipase (LPL), a key enzyme in the regulation of triglyceride-rich lipoproteins in plasma. 5 The dyslipidemia seen in established but untreated hypertension comprises raised plasma levels of total cholesterol, total triglycerides, and low-density lipoprotein (LDL) cholesterol, frequently accompanied by a reduced concentration of high-density lipoprotein (HDL) cholesterol. 6 -8 Many epidemiological studies have shown an independent inverse relationship between HDL and the risk of developing coronary heart disease (CHD it is as yet unclear at which stage in the hypertensive process dyslipoproteinemic changes occur and how they are related to blood pressure, obesity, and other metabolic variables. To elucidate this, one could either perform long-term follow-up studies of a great number of normotensive subjects or undertake case-control studies of hypertensive subjects at an early stage and normotensive control subjects. We have chosen to investigate a population-based group of men with borderline hypertension (BHT) and age-matched normotensive (NT) control subjects from the same population. Our focus was on plasma lipoproteins, postheparin plasma LPL and HL activities, insulin levels, and anthropometric data. Methods Study GroupsIn 1985, a blood pressure screening program was started in Akersberga, a small community 80 km north of Stockholm. All men aged 35 to 55 years were asked by mail to visit the primary health care center and have their blood pressure measured. Indiviuals with a diastolic blood pressure (DBP) greater than or equal to 85 mm Hg were tested repeatedly on three different occasions of at least 1 week apart. From a sample of 2694 people, a total of 207 individuals had a DBP of 85 to 94 mm Hg on all three occasions and were classified as BHT. Of these, 14 declined further participation, leaving a group of 193 subjects. The 193 subjects were followed with yearly follow-up visits for 3 years. At these follow-ups, approximately 20% of the subjects had become hypertensive and 20% had become normotensive, with the major change (13% to 15%) occurring already at the

Effects of Co‐exposure to Noise and Mixture of Organic Solvents on Blood Pressure

“…Important but uncontrolled risk factors of hypertension among our study subjects include low-density lipoprotein cholesterol, salt in diet and dietary potassium 29,30) . These unmeasured factors might have contributed to the sustained differences seen between the high-exposure groups and the low-exposure group.…”

Antibodies to Lysophosphatidylcholine Are Decreased in Borderline Hypertension

“…26,27 The insulin resistance was calculated (cIR) with the formula IRϭfasting insulin/22.5 e Ϫln(fasting glucose)…”

“…L-␣-Lysophosphatidylcholine (LPC; from egg yolk type 1, produced with phospholipase A 2 treatment) was obtained from Sigma Chemical Co. LDL was isolated as described 27 from the plasma of healthy donors through sequential preparative ultracentrifugation in a 50.3-Ti Beckman fixed-angle rotor (Beckman L8-80 ultracentrifuge) for 48 hours at 1°C and collected in the density interval of 1.025 to 1.050 kg/L. The LDL was oxidatively modified as previously described.…”

Autoantibodies to OxLDL Are Decreased in Individuals With Borderline Hypertension

“…19 BHT was defined as diastolic blood pressure (DBP) of 85 to 94 mm Hg, and the screening identified 81 men who remained within the range for BHT during repeated measurements over a 3-year period. From the same population, 80 age-matched control subjects were recruited, whose blood pressures were measured on 2 occasions a few weeks apart and were Ͻ80 mm Hg on both occasions.…”