One theory supporting online access to health records is that if patients can look up their test results and put in for prescription refills online, they'll make fewer unnecessary trips or calls to the office. That would save both patients and the health system time and money.

Although some past studies have been consistent with that idea, the new report, published in the Journal of the American Medical Association, questions whether online records always make care more efficient.

"Even after very close examination, it was hard to sort out exactly why the results were different," said Dr. David Bates from Brigham and Women's Hospital in Boston, who co-wrote an editorial accompanying the study.

"But it's a very important question, what the impact of using a personal health care record is on patient utilization," he told Reuters Health. "I strongly believe that patients are going to find this very helpful and that it will be possible to use the personal health record in ways that do improve efficiency."

Researchers from Kaiser Permanente Colorado in Denver compared 44,321 health plan members who had access to their medical records and could email their doctors to an equal number who didn't use the online system. The patients in each group were matched for age, gender, race and chronic diseases.

The researchers found patient visits and calls tended to go up in the year after people started using the electronic records. But for those in the no-access group, measures of health care use typically declined or stayed constant compared to the year before.

Online users went to the doctor's office an average 0.7 extra times each over the year and called an extra 0.3 times each, versus non-users. Their rate of after-hours clinic visits, ER trips and hospitalizations also rose in comparison - by an extra 11 to 20 visits and stays for every 1,000 patients each year.

Dr. Ted Palen from the Institute for Health Research at Kaiser Permanente Colorado and his colleagues calculated that if the same findings applied to a small group practice, a doctor with 1,000 patients who started using online records would have close to 10 extra clinic visits every week.

The researchers said there are a few possible explanations for the "surprising" findings. It's possible that online access allowed people to identify more health concerns, for example, or that the type of patients who sign up for online access are also the ones who are more likely to use in-person health services.

"Our findings suggest that the relationship between online access and utilization is more complex than the simple substitution of online for in-person care suggested by earlier studies," Palen's team wrote.

Bates said the key to making health care more efficient using online records may be building in tools specifically designed for people with chronic diseases.

For example, he said one function could allow people with hypertension to regularly enter their blood pressure online after measuring it at home. If it's too high, they would get contacted by the system or their doctor. That could eliminate the need for those patients to come into the office regularly to have their blood pressure checked, Bates said.

"Patients love the ability to interact with their own health record and with their provider (online)," Palen told Reuters Health.

Even if patients who use the online records do end up coming in for care more often, he said more engagement with the system and their doctors, though expensive in the short run, may ultimately lead to better health.

"I wouldn't say you should look at this study and say, 'We shouldn't implement these kinds of things,' because I think it is beneficial for providers and patients," Palen said.

SOURCE: bit.ly/JjFzqx Journal of the American Medical Association, online November 20, 2012.

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