Review: the effects of antihypertensive agents on serum lipids

The effect of abdominal obesity on insulin sensitivity and serum lipid and cytokine concentrations in African women

OBJECTIVES

Studies have shown clear associations of abdominal obesity with lipid and glucose metabolism and cytokine levels in a number of different population groups. However, no such studies have been performed in an African population in which visceral adipose tissue levels have been shown to be lower than in European subjects.

DESIGN AND PATIENTS

Cross-sectional analysis in 124 African women.

MEASUREMENTS

Fasting serum samples were taken from all subjects and anthropometric measurements obtained. Blood levels of glucose, insulin, total cholesterol, high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol, triglyceride, interleukin (IL)-6, IL-8 and IL-18 were measured. Subjects were separated into normal and abnormal glucose tolerant groups and into tertiles according to waist circumference (WC). Insulin resistance was assessed using the homeostasis model assessment (HOMA).

RESULTS

Abnormal glucose-tolerant subjects had higher WC, glucose and HOMA levels than the normal glucose-tolerant group. Increased WC was associated with higher triglyceride, insulin and HOMA levels and lower HDL levels. Multiple regression analyses showed that WC associated positively with HOMA and serum triglyceride levels and negatively with HDL levels. IL18 was a positive but weak determinant of the HOMA level and BMI correlated positively with serum IL-6 concentrations.

CONCLUSIONS

Although previous studies have shown that African subjects have a lower visceral adipose depot size than European subjects, abdominal obesity is still associated with insulin resistance and dyslipidaemia. The association between abdominal obesity and metabolic dysfunction within this population is not dependent upon IL-6, IL-8 or IL-18.

Systemic adverse effects of beta-adrenergic blockers: an evidence-based assessment

PURPOSE

To present an evidence-based review of the systemic adverse effects of beta-adrenergic blockers and recommend safety guidelines for use of ophthalmic beta-adrenergic blockers.

DESIGN

Literature review of published articles in peer-reviewed journals and medical texts.

METHODS

Pre-MEDLINE and MEDLINE search of relevant English language articles from 1966 to the present. Cardiovascular, pulmonary, endocrine/metabolic, central nervous system, sexual, exercise, and neuromuscular effects of systemic or ophthalmic beta-adrenergic blockers were reviewed.

RESULTS

Systemic beta-adrenergic antagonists unequivocally reduce mortality in patients with mild, moderate, and even severe congestive heart failure. Development of symptomatic bradycardia on systemic or ophthalmic beta-adrenergic blockers alone likely indicates underlying cardiac conduction disturbances. Beta 2-adrenergic blockade, regardless of route of administration, may exacerbate or trigger bronchospasm in patients with asthma or pulmonary disease associated with hyper-reactive airways. This review identifies no scientific studies supporting the development of worsening claudication, depression, hypoglycemic unawareness, or prolonged hypoglycemia in non-insulin-dependent diabetes, sexual dysfunction, or impaired neuromuscular transmission with systemic or ophthalmic beta-adrenergic blockers.

CONCLUSIONS

Many commonly presumed adverse beta-adrenergic blocker effects observed via systemic or ocular administration are not supported by published randomized clinical trials. Wide acceptance of such traditionally purported side effects has been largely due to propagation of isolated case reports and short series as well as personal communication felt to reflect expert opinion. Many more patients may be eligible to use these drugs. Obtaining a careful medical history and checking pulse rate and rhythm in the office should identify the vast majority of patients with potential cardiopulmonary contraindications.

Safety of drugs commonly used to treat hypertension, dyslipidemia, and Type 2 diabetes (the metabolic syndrome): part 2

It is becoming increasingly acknowledged that people with Type 2 Diabetes represent what can be termed "an enriched population": a group that has the greatest risk of morbidity and mortality from cardiovascular diseases such as myocardial infarcts and strokes. Due to the tremendous toll, both human and financial, that these cardiovascular diseases result in, major efforts are being put forth to decrease their occurrence. It is clear that success in this endeavor is optimized by achieving target levels of glucose, blood pressure, and cholesterol. Analysis of the individual drugs used to treat these comorbidities of the cardiovascular dysmetabolic syndrome has brought an understanding that frequently monotherapy is ineffective, and a clear appraisal of the benefits of available pharmaceuticals can result in a successful decision about which agents to include in regimens of combination therapy. This success translates into ultimately reducing the untimely death and disability that is unfortunately all too common among the people with these illnesses. As diabetes continues to be increasing alarmingly among all segments of the population, there is an urgency for this need. The knowledge is present; only the application is not.