The number of prescriptions filled by adults using Medicaid rose 19% in states that expanded Medicaid compared to states that did not under the Affordable Care Act, according to a new study from the Harvard T.H. Chan School of Public Health.

The largest increases were for drugs that help patients deal with chronic conditions, including diabetes.

“We knew the Medicaid expansion had improved access to care, but this study gives us much more detail about what that really means for patient care. Medications for conditions like diabetes and heart disease can be life-savers,” co-author Benjamin Sommers said in prepared remarks.

Then-president Barack Obama’s sweeping healthcare legislation expanded Medicaid eligibility in certain states to millions of adults in 2014.

The team of Harvard researchers looked at pharmacy transaction data from 2013 to 2015 and compared the number of prescriptions filled in states that expanded Medicaid and those that did not. The team also considered the source of insurance coverage for each prescription.

Over the 1st year and a half of the Medicaid expansion, prescriptions for diabetes drugs grew by 24% – the largest growth among all types of drugs. Contraceptives, cardiovascular drugs and mental health medicines also saw large increases within expansion states.

The team also noted that within expansion states, regions with more uninsured people prior to the ACA experienced the largest increases in prescription drug utilization after the healthcare bill went into effect.

Increases in prescription drug usage were greater in regions with larger Hispanic and black populations. The researchers reported that this could support the hypothesis that Medicaid expansion may help to close ethic and racial disparities in terms of medication access.

Lawmakers on Capitol Hill are battling it out over the future of healthcare, with some hoping to preserve the ACA and others fighting for repeal and replacement.

In late March, Republican leaders pulled their ACA replacement bill from the U.S. House of Representatives due to a shortage of votes. Now reports have said they are nearing completion for a new bill.