DENVER (FRONTLINE MEDICAL NEWS) – Evidence continues to mount that ankylosing spondylitis patients are at increased risk for developing various comorbidities, compared with the general adult population.

Patients newly diagnosed with ankylosing spondylitis (AS) had twice the rate of new-onset depression during the first 3 years following diagnosis, compared with matched people from the general population in a study of more than 21,000 American adults. Patients with newly diagnosed AS also had a 60% higher rate of developing a new cardiovascular disease, compared with the matched general population, Jessica A. Walsh, MD , said at the annual meeting of the Spondyloarthritis Research and Treatment Network.

“We need to figure out what to do about all the comorbidities. Rheumatologists need to either screen their AS patients for comorbidities, or they need to be sure their patients are plugged in with another physician who will screen them,” said Dr. Walsh, director of the spondyloarthritis clinic at the University of Utah in Salt Lake City.

Her analysis used data from the Truven Health MarketScan databases for U.S. patients covered by Medicare or commercial health insurance, and included 6,370 patients with newly diagnosed AS and 14,988 adults matched by age and sex. The analysis only included AS patients who were free from comorbidities during the 2 years prior to their AS diagnosis. The average age of the people in the study was 52 years, and 54% were men.

During an average follow-up of 2.9 years following initial AS diagnosis, the most common comorbidity among the AS patients was uveitis, which occurred nearly 15-fold more frequently among the AS patients than in the controls. Other common incident comorbidities included inflammatory bowel disease, nearly sixfold more common among the AS patients, and osteoporosis, which was nearly threefold more common during follow-up after AS diagnosis, compared with the controls.

Other comorbidities with increased incidence in the AS patients included sleep apnea (80% more common among the AS patients during follow-up), asthma (50% more often), hypertension (44% more common), malignancy (23% more common), diabetes (20% more common), and dyslipidemia (11% more common). All these incidence rates represented statistically significant increases in the AS patients, compared with the controls.

A related analysis reported by Dr. Walsh also used data from the Truven Health databases for a somewhat larger group of AS patients, 6,679 followed for 1 year after their AS diagnosis, and 19,951 matched controls. The AS patients had a significantly higher rate of hospital admissions – 12%, compared with 6% among the controls – and a significantly higher rate of emergency department visits, at 23%, compared with 15% among the controls. The AS patients also had double the rate of physician office visits and prescribed medications.

“Obviously, the AS patients are not as healthy,” Dr. Walsh said in an interview. “We adjusted for their comorbidities, but that did not affect the hospitalization rates. We need to look into this more; I don’t know why the AS patients are being hospitalized. Typically AS itself does not lead to hospitalization, so I suspect it’s because of comorbidities, or perhaps because of adverse events from treatment.”

Dr. Walsh is a consultant to AbbVie and Novartis.

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