Persons with sarcoidosis were found to have double the risk of hospitalization, compared with age-matched controls in a population-based cohort study that also linked glucocorticoid use with an increased risk of hospitalization in this group.
Using data from the Rochester Epidemiology Project record-linkage system, Patompong Ungprasert, MD, an assistant professor of medicine at the Mayo Clinic in Rochester, Minn., and his colleagues identified 345 incident cases of sarcoidosis recorded between 1976 and 2013, confirmed by individual medical records (Ann Am Thorac Soc. 2017 Feb 8. doi: 10.1513/AnnalsATS.201610-750OC). Using random selection, each patient was age- and sex-matched with sarcoidosis-free controls taken from the same database. Medical records across the study were examined for community-acquired infections requiring hospitalization that occurred after the index date or the date of diagnosis.
The nearly all white population across the study had an average age of 45 years and was evenly divided according to sex. The mean length of follow-up was 15 years for the study arm, and 16.8 years for controls. Risk factors for infection, such as smoking status, obesity, diabetes, and others were also matched, although there were nearly twice as many controls who smoked, compared with study subjects – 36% vs. 19% (P less than .001) – whereas the obesity rate was twice as high in the study arm: 41% vs. 21% (P less than .001). Results were adjusted for sarcoidosis patients who either had or had not been exposed to immunosuppressive therapies.Dr. Ungprasert and his coinvestigators found that those with sarcoidosis had double the risk of all forms of specific hospitalized infection when compared with controls – a 2.00 hazard ratio (95% confidence interval, 1.41-2.84). The results were similar when adjusted for infection risk factors: 2.13 HR (95% CI, 1.35-3.34).
The risk of hospitalized infection in the sarcoidosis arm was higher than in controls regardless of disease stage: an HR of 1.70 (95% CI, 1.12-2.58, P = .013) in those with Stage I; an HR of 2.00 (95% CI, 1.22-3.29, P = .006) among those with stage II; and an HR of 2.63 (95% CI, 1.58-4.39, P less than .001) in those with Stage III and Stage IV disease.
Biopsies taken in 251 cases resulted in 229 positive results for noncaseating granuloma, and just over half of patients had stage I disease. Stage II disease was found in 29%, Stage III in 15%, and Stage IV in 2%.
Patients in the sarcoidosis group who had not been exposed to immunosuppressive treatment had significantly higher risk of hospitalization with an HR of 1.73 (95% CI, 1.16-2.60; P = .008) when compared with controls. The risk was even higher in study patients who had received immunosuppressive therapy: an HR of 2.41 (95% CI, 1.60-3.64; P less than .001), when compared with controls. Less than half of all sarcoidosis patients required immunosuppressive therapy at any point during follow-up: about 37% by year 30 after original diagnosis. Oral glucocorticoids were the most commonly prescribed medication, used in 113 cases.
A baseline diffusing capacity of the lung for carbon monoxide was associated with an overall increased risk of hospitalized infection, with an HR of 1.15 per decrease of 10% predicted in diffusing capacity of the lung for carbon monoxide (95% CI, 1.01-1.32). A baseline forced vital capacity was associated with an increased hospitalized pneumonia risk with an HR of 1.15 per decrease of 10% predicted in forced vital capacity (95% CI, 1.01-1.32).
Although the use of immunosuppressive agents was not significantly associated with the risk of hospitalized infection (HR, 1.43; 95% CI, 0.94-2.19), current use of oral glucocorticoids, whether alone or as adjunct to immunosuppressive therapy, significantly predicted risk of infection in patients with sarcoidosis, with an HR of 3.03 (95% CI, 1.33-6.90) for oral glucocorticoids up to 10 mg per day, and an HR of 4.48 (95% CI, 1.33-6.90) in patients taking oral glucocorticoids at more than 10 mg per day, when compared with controls.
In an interview, Dr. Ungprasert said the results were not surprising, but provided the following takeaways from this study for physicians caring for patients with sarcoidosis.
“These patients are at an increased risk of serious infection and should seek medical attention as soon as possible when they develop symptoms of infection, such as fever or chills,” he said in an interview. “Keeping current with vaccinations is also important for them.”
Dr. Ungprasert also said the study serves as a reminder to use oral glucocorticoids judiciously. “When considering their use, the physician should keep in mind that a large number of patients with sarcoidosis will have a spontaneous resolution of the disease.”
There were no relevant disclosures. The study was funded in part by the National Institute on Aging.
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