It's unclear whether the health benefits outweigh
the risks of the widely prescribed diabetes drug
pioglitazone (brand name Actos), say the authors
of a review that examined 22 studies of the drug
involving 6,200 type 2 diabetes patients.
"Our results showed that published scientific
studies of at least 24 weeks of pioglitazone treatment
in people with type 2 diabetes mellitus did not
provide convincing evidence that patient-oriented
outcomes like mortality, morbidity, adverse effects
and health-related quality of life are positively
influenced by this drug," lead author Dr.
Bernd Richter said in a prepared statement.
Not only were he and his colleagues unable to
identify any definite benefit from taking pioglitazone,
they also found that patients taking the drug
had increased rates of edema (fluid buildup and
swelling) and heart failure.
They also concluded that the drug may cause dangerous
drops in blood glucose in people taking pioglitazone
in combination with another class of drugs called
sulfonylureas, which include medications such
as tolbutamide, glipizide and glimepiride, among
others.
"Until new evidence becomes available, the
benefit-risk ratio of pioglitazone therapy in
type 2 diabetes mellitus remains unclear,"
said Richter, an assistant professor in the department
of endocrinology, diabetes and rheumatology at
Heinrich Heine University in Germany.
Richter said pioglitazone treatment should be
restricted to patients who show real benefits
-- fewer diabetic complications and improved health-related
quality of life -- from taking the drug. The findings
are published in the current issue of The Cochrane
Library journal.
Pioglitazone belongs to a family of drugs called
thiazolidinediones. These kinds of drugs are designed
to increase the body's sensitivity to naturally
produced insulin to foster better uptake of glucose
into cells and lower blood-glucose levels.
"The kernel from this review is that pioglitazone
is effective in glucose-lowering, has some other
beneficial and potentially harmful associated
features, and just has not been evaluated in the
right way to prove that it will help people lead
longer and more productive lives," Dr. John
Buse, director of the Diabetes Care Center at
the University of North Carolina School of Medicine
at Chapel Hill, said in a prepared statement.
"This is true for essentially every drug
available for the treatment of diabetes,"
noted Buse, who was not involved in the review.
