(Reuters Health) - Workers with diabetes who switch to high-deductible health plans that require paying more out-of-pocket for care may be more likely than those who remain in low-deductible plans to delay needed checkups, a U.S. study suggests.

People with diabetes are at risk for life-threatening blood vessel diseases. Left untreated, these conditions can lead to complications such as heart attack, stroke and amputation.

For the study, researchers examined data on almost 34,000 people with diabetes who initially had employer-sponsored health plans with deductibles of $500 or less - but then their employers switched to offering only plans with deductibles of $1,000 or more. The study team also looked at a comparison group of almost 295,000 workers with diabetes who consistently had deductibles of $500 or less.

Before the first group switched to higher deductible health plans, there were no meaningful differences between the groups in how long patients waited to get care for complications that can be life-threatening without timely treatment, the study found.

But over the four years after some employers switched to offering only high-deductible plans, the patients on these plans waited an average of 1.5 months longer than people on low-deductible plans to seek care for new symptoms of cardiovascular complications associated with diabetes, 1.9 months longer for diagnostic tests and 3.1 months longer for medical procedures to treat these complications.

“We found that delays or reductions in care for cardiovascular disease persisted over a relatively long follow-up and occurred even for services that are used for life-threatening conditions,” said study leader Dr. Frank Wharam of Harvard Medical School and Harvard Pilgrim Health Care Institute in Boston.

An increasing proportion of Americans, including people with diabetes, have high-deductible health insurance plans requiring them to pay up to about $1,000 to $7,000 out-of-pocket per year if they use healthcare services, researchers note in the Annals of Internal Medicine. But studies to date haven’t offered a clear picture of how this added cost might impact healthcare utilization for people with diabetes.

The study can’t prove whether or how costs might have influenced how long patients waited to get any needed exams, lab tests or treatments.

But it’s likely that money played a role because everyone in the study had diabetes with similar risks of cardiovascular complications, Wharam said by email.

“We can speculate that diabetes patients’ knowledge of the high cost of care, and a desire to save money, led to these patterns,” Wharam said.

All of the patients in the study had employer-sponsored health insurance provided by a single large health insurance company in the U.S. between 2003 and 2012, and their employers did not offer more than one option for insurance in any given year.

People who switched to high-deductible plans were 6 percent less likely to seek care for the first new major symptom of complications during the study, such as chest or leg pain. They were also 9 percent less likely to get the first diagnostic test they needed and 9 percent less likely to get procedures to treat these complications.

Compared to the people who remained in low-deductible plans throughout the study, those who switched to higher-deductible plans had their out-of-pocket health costs increase by an average of 43 percent to 53 percent per year.

The research team couldn’t verify why patients may have chosen to wait for needed care, making it impossible to prove that increased costs were partially or completely responsible, the authors note.

“I am not aware of any rigorous studies that ask about motives and thought processes, but the economic model would suggest that a person who would have to pay more would delay care for mild symptoms that might resolve on their own,” said Mark Pauly of the Wharton School and the Perelman School of Medicine at the University of Pennsylvania in Philadelphia.

“Someone whose care is free because insurance covers it would be more likely to seek care at the first sign of a symptom,” Pauly, author of an accompanying editorial, said by email.

SOURCE: bit.ly/2qUsCyw and bit.ly/2Q6vTcf Annals of Internal Medicine, online November 19, 2018.