* U.S. health secretary writes governors
* Says states should ensure enforcement power
* California miscalculation isolated case-WellPoint
(Adds WellPoint comment, updates shares)
WASHINGTON, May 5 U.S. Health Secretary
Kathleen Sebelius is calling on states to re-examine WellPoint
Inc's WLP.N health insurance rate increases.
In a letter to state governors released on Wednesday,
Sebelius urged them to check WellPoint's accounting assumptions
and ensure that state insurance offices have the power to
review and approve any insurance rate increases.
WellPoint has been battered amid the recent healthcare
reform debate as Democratic lawmakers pointed to the company's
Anthem unit in California, which increased rates in some cases
as much as 39 percent.
The insurer recently withdrew that increase after
California officials found it was based on "unreasonably high
assumptions" about rising medical costs, Sebelius wrote.
"In light of this recent finding, I urge that, to the
extent you have authority to do so, you re-examine any
WellPoint rate increases in your state to determine whether any
mistaken assumptions similar to those made in California were
made in your state," she said.
"Even small errors can mean unaffordable premiums for
policyholders," she added.
WellPoint spokeswoman Kristin Binns said that "the
miscalculation was unique" to its filing in California.
She added that health insurers have to file their next
year's rates "based on actuarial projections of medical trends
in advance for the year to come."
Despite the healthcare reform law passed in March, the
review of health insurers' annual premium increases remains
largely in states' hands. A bill being considered by Democrats
in Congress would give the U.S. health secretary power to
review and reject premium increases found to be unfair.
Shares of WellPoint were off 9 cents, or 0.2 percent, at
$52.51 in afternoon trade the New York Stock Exchange.
A copy of the letter to state governors is on the U.S.
Department of Health and Human Services website here.
(Reporting by Susan Heavey; editing by John Wallace and Gerald