With the deadline to sign up for insurance through the Affordable Care Act passed, more than 700,000 people in Texas have signed up. The deadline was originally set for March 31, but it was extended by the Obama administration to April 19, in part to account for technological troubles with the federal website.

Roughly 30 percent of Texas enrollees—or 220,127 people—were previously uninsured, according to data from the Urban Institute, a nonprofit social and economic research group. Data is not yet available for individual counties.

The number of uninsured who signed up through the ACA is notable but just a drop in the bucket given Texas' large population of uninsured going into the ACA, said Vivian Ho, James A. Baker III Institute Chair in Health Economics at Rice University.

"There were around 800,000 uninsured people in Harris County alone," she said. "In other states, [220,127] would be a big dent, but we have several million uninsured in Texas. The percentage effect on the overall population is small."

The increase in the number of people insured is not enough to affect the bottom lines of area hospitals and doctors, Ho said. Bryan McLeod, a spokesperson for Harris Health System, said the percentage of patients coming to them for help who do not have insurance—around 65 percent—has not changed since the ACA implementation. However, hospitals are preparing for those numbers to continue to increase.

"Even if Texas doesn't set up ACA exchanges, it could expand insurance to low income patients in other ways," Ho said. "Harris County hospitals serve huge populations of uninsured people. If they get some sort of coverage, that is a big boon. I think business will push the Legislature to create an option for the low-income population. It does not make good business sense to ignore that money."

Methodist Hospitals have been developing programs to reach the underserved based on its 2013 ACA assessment. At Methodist's Willowbrook location—which serves a 2,242-square-mile area of Harris and Waller counties with an estimated population of 4.3 million—priorities focus on fostering community partnerships and providing more access to low-level and emergency care in suburban areas, officials said.

Memorial Hermann, which operates several imaging centers and medical groups in the Cy-Fair area, has been fine-tuning its Accountable Care Organization, which integrates care in ways meant to lower costs and improve quality by expanding the physician network and bringing in more physicians to cover primary care. Memorial has also been making an effort to reduce expenses to prepare for a future that involves less fee-for-service and more fixed payments, hospital officials said.

"We are moving more to value-based payment," Dan Wolterman, president and CEO of Memorial Hermann said in a statement. "We had a little time to get ready for massive change in payment systems, but we have to be in motion now. Health care reform exacerbated the timeline for making this shift, but we would have had to do it regardless."