Denver, CO—Patients with gout who also have osteoarthritis (OA) are more likely to be hospitalized and experience delays in starting urate-lowering therapy compared with those with gout who do not have OA. Patients with gout and comorbid OA are also more likely to benefit from earlier and more aggressive treatment, according to the results of a poster presented at the 2017 Academy of Managed Care Pharmacy Managed Care Annual Meeting.
“Concomitant gout and OA represent a unique burden of disease, associated with increased disease severity and greater management challenges. Healthcare costs are higher for patients with gout and OA than those without OA,” Svetlana Krasnokutsky Samuels, MD, Assistant Professor, Department of Medicine, New York University Langone Medical Center, and colleagues reported.
The investigators sought to identify characteristics relative to OA comorbidity among patients with gout, and to evaluate the effects that OA comorbidity have on treatment patterns and use of healthcare in this population. They noted that their study was one of the first of its kind to explore the association between the management of patients with gout and OA.
Using the chart audits and structured case report forms of adult patients with a confirmed diagnosis of gout who received treatment from 125 practice-based rheumatologists and 125 primary care physicians who managed ≥50 patients with gout on a yearly basis in the United States, Dr Samuels and colleagues conducted a descriptive and multivariate statistics analysis of differences between patients with gout who do and do not have comorbid OA. They also evaluated the impact of OA comorbidity on treatment trends and the use of healthcare resources in patients with gout.Patient Characteristics, Comorbidities, and Disease Severity
A total of 1159 patient charts were abstracted; 230 patients had gout and OA, and 929 had gout without OA. Among patients with gout who were aged ≥61 years, 63.0% were identified as having comorbid OA. The majority of patients in the study were white (71.2%) and men (80.5%). Severity of gout was determined by physician global assessment, number of flares, physician-evaluated damage to organs and/or joints, and tophi.
The investigators reported that several comorbidities were significantly more common in patients with gout and OA than in patients with gout but no OA. These included chronic obstructive pulmonary disease (10.4% vs 5.1%, respectively), cardiovascular disease (29.6% vs 13.8%, respectively), chronic renal disease (24.8% vs 10.0%, respectively), hyperlipidemia (47.0% vs 27.6%, respectively), diabetes (31.3% vs 18.7%, respectively), obesity (42.6% vs 20.1%, respectively), prostate disease (men; 22.7% vs 3.8%, respectively), and depression (21.7% vs 12.2%, respectively).
In terms of severity of disease, patients with gout who also had OA were more likely to have tophi, clinician-rated severe gout, and joint damage (Table).
Dr Samuels and colleagues reported that patients with gout and comorbid OA were more likely to receive therapy from a rheumatologist than a primary care physician compared with those with gout and no OA (66.09% vs 33.91%, respectively). Patients with gout and OA were also more likely to receive urate-lowering therapy than patients who did not have OA (89.13% vs 70.40%, respectively).
The mean time from when patients were first diagnosed with gout until the time they were started on current urate-lowering therapy was longer in those who also had OA than in those who did not have this comorbidity (32.39 vs 18.44 months, respectively).
Furthermore, in patients with gout who were treated with allopurinol, those with OA received a higher dose of the drug (325 mg) compared with those without OA (296 mg). The investigators also noted that, although gout control rates were found to be low in both groups of patients, use of urate-lowering therapy was associated with a greater rate of gout control.
Results of this study also revealed that patients with gout and comorbid OA were more likely to be hospitalized, visit the emergency department, and undergo surgery for gout in the past 12 months than their counterparts without OA. Patients who had both diseases also visited their physician’s office more frequently than patients with gout only.
The investigators concluded that gout was poorly controlled in patients with and without OA, but noted that patients with gout and comorbid OA were more likely to have a delayed start of urate-lowering therapy following their gout diagnosis.
“Gout patients with comorbid OA constitute a less healthy group who may benefit from earlier, more aggressive therapy,” they said.