The Commonwealth Fund's Biennial Health Insurance Survey said 80 million working U.S. adults skipped needed medical care due to cost in 2012, up from 75 million people in 2010 and 63 million in 2003, CNN/Money reported.
People who were uninsured or under-insured were most likely to have trouble affording care, but 28 percent of working-age adults with good insurance also had to forgo treatment because of the price.
Nearly 3-in-10 adults said they did not visit a doctor or clinic when they had a medical problem, while more than a quarter did not fill a prescription or skipped recommended tests, treatment or follow-up visits.
Twenty percent said they did not get needed specialist care because of the expense and 28 percent of those who needed medication for a chronic condition like hypertension, diabetes, heart disease and asthma did not fill prescriptions or skipped doses because they couldn't afford to pay for the drugs.
Those with healthcare coverage found themselves shelling out more for deductibles and co-payments.
The share of Americans with deductibles greater than $1,000 more than tripled from 2003-12.
"Costs of healthcare have gone up faster than wages," David Blumenthal, president of The Commonwealth Fund, told CNN/Money.