New research presented at the 65th Annual Scientific Sessions of the American Diabetes Association (ADA) suggests that Avandia (rosiglitazone maleate), a medication that helps control blood sugar levels, may also reduce blood pressure in people with type 2 diabetes. According to the American Heart Association, patients with type 2 diabetes are two to four times more likely to develop cardiovascular disease.
In one study (abstract number: 542-P), combination therapy with Avandia and metformin or a sulfonylurea demonstrated sustained reductions in blood pressure in people with type 2 diabetes compared to combination treatment with metformin and a sulfonylurea. High blood pressure, also known as hypertension, is a common risk factor for cardiovascular disease.
In a second study (abstract number: 543-P), in addition to reducing blood pressure, Avandia in combination with metformin reduced microalbuminuria in patients with type 2 diabetes and microalbuminuria. Microalbuminuria, a condition where small amounts of the protein albumin are found in urine, is a marker for cardiovascular disease in all people.
"Avandia is proven to be effective in improving blood sugar control in patients with type 2 diabetes," said George Bakris, MD, professor of Preventive Medicine and Internal Medicine at Rush University Medical Center in Chicago and lead study author of one of the studies. "These new data show that Avandia may also reduce blood pressure and microalbuminuria, which are associated with cardiovascular disease."
Eighteen million Americans are affected by diabetes. Type 2 diabetes accounts for 90-95 per cent of all diagnosed diabetes cases. Of those Americans with diabetes, 11 million have high blood pressure. In general, 64 per cent of people with diabetes do not reach blood pressure goals, placing them at particularly high risk for cardiovascular disease. According to the Centers for Disease Control and Prevention (CDC), cardiovascular disease is one of the leading causes of death in the United States and accounts for 65 per cent of diabetes-related deaths.
Abstract number 542-P: New Study Showed Avandia to Improve Blood Pressure
A sub-study of the ongoing "Rosiglitazone Evaluated for Cardiac Outcomes and Regulation of Glycemia in Diabetes" (RECORD) trial, entitled "Twelve Months Sustained Efficacy of Rosiglitazone Combination Therapy on Ambulatory Blood Pressure in People with Type 2 Diabetes Mellitus," was solely designed to evaluate the effects of Avandia in combination with metformin or a sulfonylurea on 24-hour ambulatory blood pressure over a 12-month period.
The study included 759 people with type 2 diabetes, all of whom were inadequately controlled with metformin or a sulfonylurea. Those inadequately controlled on metformin (n="379)" were randomized to receive the addition of sulfonylurea or Avandia. Those inadequately controlled on a sulfonylurea (n="380)" were randomized to receive the addition of metformin or Avandia. Baseline characteristics were comparable between treatment groups and most participants had concurrent hypertension.
Addition of Avandia resulted in a clinically and statistically greater mean reduction from baseline to 12 months in 24-hour ambulatory diastolic blood pressure, compared to addition of a sulfonylurea (difference -2.02 mmHg) or metformin (difference -3.17 mmHg). Similar patterns of changes were also observed for 24-hour ambulatory systolic blood pressure (metformin plus Avandia vs. metformin plus a sulfonylurea: difference -2.73 mmHg; sulfonylurea plus Avandia vs. sulfonylurea plus metformin: difference -2.64 mmHg).
Abstract number 543-P: Data Found Avandia to Reduce Blood Pressure and Microalbuminuria
"Rosiglitazone Added to Metformin Reduces Urinary Albumin/Creatinine Ratio and Ambulatory Blood Pressure in Subjects with Microalbuminuria and Type 2 Diabetes" was a randomized, double blind, active-controlled study. It was conducted to assess the long-term effect of Avandia in reducing 24-hour ambulatory blood pressure and microalbuminuria [as measured by urinary albumin/creatinine ratio (UACR)] among people with type 2 diabetes and microalbuminuria.
Following a minimum of four weeks treatment with metformin, 389 participants were randomized to the add-on treatment with Avandia or glyburide for eight additional months. Study medications were titrated to ensure comparable blood sugar control. Avandia in combination with metformin produced a statistically significant reduction in UACR from baseline (22.8 per cent). However, the patient group treated with glyburide and metformin did not demonstrate a statistically significant reduction in UACR (7.1 per cent). Additionally, Avandia in combination with metformin produced a statistically greater reduction from baseline in 24-hour ambulatory systolic and diastolic blood pressure compared to treatment with glyburide and metformin (difference -3.4 mmHg systolic and -2.5 mmHg diastolic, respectively).
Treatment was generally well tolerated, with a similar incidence of adverse events, in both patient groups. Specifically, hypoglycemia was observed more frequently in the glyburide plus metformin group compared to the rosiglitazone plus metformin group (12.4 per cent vs. 1.0 per cent, respectively).
"Type 2 diabetes mellitus patients are at an increased risk for developing cardiovascular disease. In addition to controlling blood sugar levels, these data suggest that Avandia may improve blood pressure and microalbuminuria," said Alexander Cobitz, MD, PhD, senior director, Metabolism Medicine Development Center, GlaxoSmithKline. "We are pleased to be working with patients and physicians toward providing a treatment option that may help reduce the risk of serious - and potentially life-threatening - diabetes-related complications."
Long-term, landmark clinical outcomes studies are ongoing to assess the effect of Avandia on cardiovascular outcomes in patients with type 2 diabetes.
Avandia, along with diet and exercise, helps improve blood sugar control. It may be prescribed alone, with metformin, sulfonylureas, metformin plus a sulfonylurea or insulin. When taking Avandia with sulfonylureas or insulin, patients may be at increased risk for low blood sugar. Ask your doctor whether you need to lower your sulfonylurea or insulin dose.
Avandia may cause fluid retention or swelling which could lead to or worsen heart failure, so you should tell your doctor if you have a history of these conditions. If you experience an unusually rapid increase in weight, swelling or shortness of breath while taking Avandia, talk to your doctor immediately. In combination with insulin Avandia may increase the risk of other heart problems. Ask your doctor about important symptoms and if the combination continues to work for you. Avandia is not for everyone. Avandia is not recommended for patients with NYHA Class 3 and 4 cardiac status or active liver disease.
Also, blood tests to check for serious liver problems should be conducted before therapy and periodically thereafter as determined by your doctor. Tell your doctor if you have liver disease, or if you experience unexplained tiredness, stomach problems, dark urine or yellowing of skin while taking Avandia.
If you are nursing, pregnant or thinking about becoming pregnant, or premenopausal and not ovulating, talk to your doctor before taking Avandia.