For those with diabetes, controlling blood pressure is crucial, but not urgent

For those with diabetes, controlling blood pressure is crucial, but not urgent

January 9, 2012

A new study suggests that middle-aged adults recently diagnosed with diabetes and hypertension have time to try to learn how to control their high blood pressure without medications, but not too much time.

The consequences of delaying effective hypertension treatment for up to a year were small--a two-day reduction in quality-adjusted life expectancy--according to a study by University of Chicago researchers published online for the Journal of General Internal Medicine. But as the delay gets longer, the damages multiply. A ten-year delay decreased life expectancy by almost five months.

"For newly diagnosed patients, this means we have time," said study author Neda Laiteerapong, MD, instructor of medicine at the University of Chicago. "Most patients would prefer to control their blood pressure through diet and exercise rather than with medications, and it can take months to learn how to change old habits and master new skills. Our results indicate that it's OK to spend from six months to a year, perhaps even longer, to make the difficult lifestyle changes that are necessary and will pay off in the long run."

High blood pressure is especially damaging for people with diabetes, raising their risk of stroke, coronary artery disease, kidney failure, vision loss and amputations. Both the American Diabetes Association (ADA) and the National Institutes of Health recommend a lower blood pressure target for patients with diabetes than for the general public, urging them to keep their pressures below 130/80 mmHg.

Two out of three adults with diabetes, however, never reach that goal. Many patients are hampered by limited access to health care. Others are delayed by what the authors call "clinical inertia," a disinclination by patients to implement lifestyle changes or reluctance by their doctors to push additional medications. Among those who are prescribed blood pressure drugs, at least 20 percent of patients with diabetes do not stick to their treatments.

Until now, the implications of these delays on patients' health had not been quantified. Laiteerapong and colleagues built computer models using published data to determine the magnitude of harm caused by different delays in controlling blood pressure in patients from 50-59 years of age with newly diagnosed type 2 diabetes. The damage caused by a one-year delay "may be small," they concluded but delays of ten years or more were comparable to smoking in patients with cardiovascular disease.

Given time to learn how, many patients would prefer to control blood pressure through diet and exercise rather than with antihypertensive medications. Most guidelines, however, including those of the ADA, recommend at most a three-month trial of medication-free lifestyle therapy for patients with moderately elevated blood pressure. They call for immediate initiation of medication for those with blood pressure more than 10mmHg above the goal.

That is often not enough time for patients to learn the methods, develop good habits and demonstrate improvements.

"We ask patients with diabetes to do a billion things," Laiteerapong said, "to test their blood sugars, to count carbohydrates, to spend 30 minutes a day doing exercise, including cardio and weight training. Most, if not all, of this is new to them. They need time to adapt. It's important to do this right, but our results say it's not that important to do it so fast."

This study argues that caregivers should work with patients to help them gain the knowledge and develop the necessary skills gradually rather than rushing to drug treatment, especially if their blood pressure is only mildly elevated. It suggests that patients and providers "have more time," the authors write, "at least up to one year, to focus on diabetes self-management and lifestyle modification."

"Among middle-aged adults with diabetes, the harms of a one-year delay in managing blood pressure may be small," the authors conclude. "Health care providers may wish to focus on diabetes management alone in the first year after diagnosis, to help patients establish effective self-management and lifestyle modification. However, after the first year, it is clear that achieving and maintaining tight blood pressure control among US middle-aged adults with diabetes has the potential to generate substantial population-level health benefits."

The National Institutes of Health funded this study. Additional authors include Priya John, David Meltzer and Elbert Huang, all of the University of Chicago.