Metformin Response Predicts Disease Progression
In Diabetes Today
28-MAR-2006
Metformin Response Predicts Disease Progression
In type 2 diabetes patients who are treated with
metformin alone, those who achieve low levels of
glycosylated hemoglobin level (HbA1c), a common
measure of blood sugar, in the first year have a
longer period of drug effectiveness, investigators
report.
Because diabetes is a progressive disease, patients
typically undergo a succession of drug therapy
adjustments, Dr. Gregory A. Nichols and his associates
point out. If drug effectiveness is maximized at each
disease stage, treatment flexibility will be increased
and blood glucose levels will be reduced in the long
term, they add.
To identify predictors of metformin response, Nichols’
group evaluated the records of patients treated
between 1996 and 2003 at Kaiser Permanente Northwest
HMO in Portland, Oregon. They identified 1,547
patients with diabetes whose first drug was metformin.
According to their report in Diabetes Care, the most
important factor predicting long-term success with
metformin was the reduction of HbA1c achieved during
the first year.
For example, about half of the patients whose lowest
blood sugar level was between 7 and 7.9 percent in the
first year had to switch drugs or have another drug
added within 36 months. In contrast, patients whose
blood sugar was less than 6 percent in the first year
did not require a switch or another drug for 84
months.
Another important factor that predicted response to
metformin was weight loss. The authors found that
patients who needed to add or switch drugs lost an
average of 1.9 kg, (4.2 lbs) compared with an average
loss of 5.0 kg (11.0 lbs) among those who remained on
metformin monotherapy.
"Our results indicate that if glycemic control is
achieved initially with metformin monotherapy, it can
be successfully maintained for several years," Nichols
and his associates conclude.
This study was supported by Merck & Company, the
manufacturer of metformin