People with psychiatric illnesses are more likely to have complications after hip replacement surgery, according to a recent analysis.

This added risk is something doctors and patients should discuss in advance, the study team writes in The Journal of Arthroplasty.

Previous studies have linked depression and other mental illnesses to greater complications after surgery and worse outcomes for patients, the researchers note.

In particular, patients with psychiatric disease are known to have more complications after cardiac, spine and general surgery, lead author Dr. Mitchell Klement told Reuters Health.

"We wanted to see if the same effect was true in total hip replacements," said Klement, an orthopedic surgery resident at Duke University Medical Center in North Carolina.

Total hip arthroplasty, done to relieve pain from advanced hip arthritis, involves replacing the hip joint with an artificial one and is usually very successful, the authors note.

But complications can range from pain and infections to blood clots and stroke, failure of the surgical wound to heal, heart rhythm abnormalities and heart failure, kidney failure and respiratory failure.

To determine how mental illness might affect healing after hip surgery, the researchers analyzed data from Medicare, the government insurance for elderly and disabled, from 2005 to 2011.

They identified 86,976 patients who had hip replacements and also had a diagnosis of one or more of three common psychiatric diseases. Within this group, 5,626 had bipolar disorder, 82,557 had depression and 3,776 had schizophrenia.

The researchers compared them to 590,689 people who had hip surgery but did not have a mental illness.

The patients with psychiatric diagnoses were more likely than those without mental illness to be younger than 65, female and to have additional medical problems.

Three months after surgery, patients with mental illness were more likely to have had 13 of the 14 medical complications studied.

The artificial hips of people with mental illness were more than twice as likely to get infected, break or get dislocated, for example.

Hip surgery patients with psychiatric disease were also nearly twice as likely to need revision surgery on their hip replacement. And they were more than twice as likely to have respiratory failure and pneumonia.

There were no significant differences in outcomes between the people with depression, bipolar disorder or schizophrenia.

"Psychiatric states reduce the ability to self-manage and follow instructions, reduce motivation for self-management, and (make it difficult to pay) attention to recommendations to protect their surgical joints effectively," said Ray Marks, a clinical professor at York College in New York who studies arthritis surgery and mental illness.

People with mental illness may be more likely to have weaker immune systems, more body fat and diabetes, all factors that can have impair healing from surgery, Marks, who was not involved in the study, told Reuters Health by email.

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People with anxiety or depression that's not being treated should discuss this with their doctor. They should be aware that doctors may not ask them about these issues, so they may have to bring it up in order to get help, she said.

"If they get help, they will have less overall pain, sleep better, and be able to improve their health outlook and health outcomes, and reduce the risk of postoperative complications," Marks added.

"Patients with these conditions can still have a total hip replacement and achieve excellent relief from their arthritis pain. However, they should know that the rates of problems after surgery might be higher," Klement noted.

"Patients should do their best to make sure all of their medical issues are under control and practice healthy exercise and eating habits in the months before their surgery," Klement said.