In systemic sclerosis, which factors are linked to an increased risk of osteoporosis and fracture?

November 11, 2020
Ingrid Torjesen

Several factors can increase the risk of fractures and osteoporosis in patients with systemic sclerosis, including poor functional status and being underweight, according to researchers reporting at the annual meeting of the American College of Rheumatology on Saturday. However, the impact of proton pump inhibitors was less clear.

Several factors can increase the risk of fractures and osteoporosis in patients with systemic sclerosis, including poor functional status and being underweight, according to researchers reporting at the annual meeting of the American College of Rheumatology on Saturday. However, the impact of proton pump inhibitors was less clear.

Systemic sclerosis is associated with several risk factors for osteoporosis and fractures, including malnutrition, physical disability, chronic inflammation, and use of corticosteroid therapy, but the specific characteristics of patients who experience these increased risks have not been clearly defined in a U.S. population.

Using data from FORWARDthe largest patient-reported research data bank for rheumatic disorders in the United StatesSina Famenini, MPH, of Johns Hopkins School of Medicine, Baltimore, and colleagues assessed osteoporosis outcomes in 922 patients: 154 patients with systemic sclerosis and 768 age and sex matched patients with osteoarthritis (ratio 1:5).

During a total of 5,046 patient-years (median 4.16 years per patient) follow-up, 90 patients received a diagnosis of osteoporosis or experienced an osteoporotic fracture.

Patients who were female, underweight and had a higher rheumatic disease comorbidity index and higher Health Assessment Questionnaire Disability Index (HAQ) scores had a greater likelihood of osteoporosis diagnosis or fracture: hazard ratios2.49(95% confidence interval: 1.09, 5.71) 4.57 (CI: 1.56, 13.4)), 1.10 (CI: 1.07, 1.39), 1.60 (CI: 1.16, 2.20) respectively. Use of several types of medications was also associated with an increased likelihood of osteoporosis diagnosis or fracture, including proton pump inhibitors (HR 1.62; CI: 1.05, 2.47)), selective serotonin inhibitors(HR 1.91; CI: 1.15, 3.18), and osteoporosis medication (HR 2.08; CI: 1.10, 3.94).

After adjusting for cofounders the researchers concluded that functional status of patients with systemic sclerosis or osteoarthritis, as measured by HAQ, is a particularly strong indicator of future fracture and osteoporosis risk (HR1.48; CI: 1.00, 2.50), as was being underweight (HR 5.37; CI: 1.69, 17.0).

“The main finding our study identified was that higher scores (more severe disability) on the Health Assessment Questionnaire (HAQ) Disability Index (DI) is a major a risk factor associated with a higher risk of fracture and osteoporosis among patients with system sclerosis,” Famenini said. “HAQ-DI quantifies a person’s abilities to perform activities of daily living (ADLs). In other words, those who were able to have active lifestyles were less likely to experience fractures or incidence of osteoporosis.”

“As systemic sclerosis is a heterogeneous disease, exercise and physical therapy regimens will likely need to be specifically tailored to each patient’s unique presentation. Our findings suggest that closely monitoring patients’ functional status is important for rheumatologists as screening for deteriorating physical function may direct early referrals for patients who would benefit from targeted exercise regimens.”

Use of proton pump inhibitors was also associated with an increased risk of osteoporosis or fracture (HR 1.58; CI: 1.01, 2.49) when data from patients with systemic sclerosis and osteoarthritis were pooled, but that association did not persist when only systemic sclerosis data were analysed (HR 0.81; CI 0.29, 2.29). The researchers concluded that while proton pump inhibitors are often associated with a higher risk of fractures and osteoporosis, such risks may vary across different disease types and that further investigation was needed to characterize their effects.

As well as studies to clarify the impact of proton pump inhibitors, more studies were needed to determine which specific interventions provide maximal benefits to systemic sclerosis patients, Famenini said. “Those interventions may be one of or a combination of osteoporosis medications, supplemental nutrition, physical therapy, weight training exercises, etc.”

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REFERENCE

ABSTRACT 0926. “Risk Factors for Fractures and Osteoporosis Among Patients with Systemic Sclerosis in a United States Cohort.” The annual meeting of the American College of Rheumatology. 9:00 AM, Saturday, Nov. 7, 2020.