Lt. Gov. Dan Patrick is urging the Teacher Retirement System not to raise health care premiums for retired teachers, arguing that state lawmakers should take on the burden of increased costs.

In a letter Wednesday, Patrick said he had been notified that the system's board of trustees was considering a proposal to increase premiums for TRS-Care, the health insurance program for retired teachers, by $50 per month for retired teachers younger than 65 who are not on Medicare, beginning in 2019. But TRS officials say the agency discussed the need for premium increases with lawmakers during last summer's special session — without the increase, TRS would need $410 million from the state to keep the health care program solvent through 2021.

Teacher Retirement System spokesman Rob Maxwell said TRS officials began meeting this week to update lawmakers on its latest financial projections. Even if the board increases the premium, TRS anticipates needing $246 million to keep TRS-Care financially sound.

The board will consider the premium increase at September's public meeting.

TRS-Care has dealt with financial woes for years. Last spring, lawmakers increased its funding $483 million over the following two years. But they also changed the structure of the program to dial back benefits in order to keep the system running, putting the financial burden on retired teachers younger than 65.

That summer, lawmakers patched that problem with a $212 million increase for TRS-Care. But the money wasn't enough for many retirees, who still saw ballooning deductibles and out-of-pocket costs.

And the money spent last year was just a temporary patch to fix a ongoing problem: The state has not created a funding structure to pay for a higher percentage of health care costs as they rise each year.

Patrick in his letter Wednesday said lawmakers should look at ways to control health care costs for retired teachers.

"I have been candid in pointing out that the Legislature will need to add significant dollars over the next several years to address the increasing costs of healthcare for retired teachers," Patrick wrote. "Because we are committed to our retired teachers, I am confident that the Senate will support additional funding for TRS Care and I am hopeful the next Speaker of the House will follow our lead on this important issue."

The Teacher Retirement System asked for approximately $2 billion more in 2020 and 2021 to cover health and pensions costs, according to a recent appropriations request.