Common Comorbidities in Gout Patients Can Affect Treatment Outcomes

February 9, 2011

Two studies highlight the challenges to effective treatment posed by hypertension, diabetes, and other comorbid conditions in patients with gout.

Two studies highlight the challenges to effective treatment posed by hypertension, diabetes, and other comorbid conditions in patients with gout.

In “Prevalence of Contraindications and Prescription of Pharmacologic Therapies for Gout,” published in The American Journal of Medicine, researchers studying the impact of comorbidities on gout treatment enrolled 575 patients with gout and stratified them into three groups according to certainty of diagnosis: International Classification of Diseases, 9th Revision, Clinical Modification code alone (cohort I), American College of Radiology criteria (cohort II), and crystal diagnosis (cohort III). They defined comorbidities according to International Classification of Diseases, 9th Revision, Clinical Modification codes and classified them as moderate or severe. They reported that hypertension was the most common comorbidity in these patients (prevalence 0.89). The presence of comorbid conditions resulted in “a high frequency of contraindications to approved gout medications,” with more than 90% of patients having “at least one contraindication to nonsteroidal anti-inflammatory drugs” and many patients demonstrating multiple contraindications to one or more gout medications. The researchers also reported that many patients were prescribed medications for which they were contraindicated. For example, 30% of patients in cohort I, 37% of patients in cohort II, and nearly 40% of patients in cohort III were prescribed colchicine despite having at least one strong contraindication to the drug. Based on these findings, the researchers concluded that “patients with gout typically harbor multiple comorbidities that result in contraindications to many of the medications available to treat gout. Frequently, despite contraindications to gout therapies, patients are frequently prescribed these medications.”

Cardiometabolic comorbidities may predispose gout patients to flares

The authors of “Frequency and Risk Factors of Gout Flares in a Large Population-based Cohort of Incident Gout,” published in Rheumatology, used data from the Health Improvement Network (THIN) database in the UK to study nearly 24,000 patients diagnosed with gout to “describe the frequency of gout flares during the study period and risk factors contributing to first gout flare in a population-based cohort of incident gout with special emphasis on comorbid conditions.” Among the study cohort, 52% of the patients had a history of hypertension, 19% had ischemic heart disease, 9% had diabetes, 3% had peptic ulcer and 4% had chronic renal failure. Women presented with a higher prevalence of cardiometabolic disorders than men. The researchers found that a history of cardiometabolic disease was associated with a greater number of flares in this cohort. Specifically, a history of ischemic heart disease, hypertension, and renal failure “were independently associated with a higher risk of a first post-diagnosis gout flare.” In their discussion of these results, the authors wrote that “a considerable proportion of patients experience flares with prevalent comorbid diseases such as IHDs or hypertension; these conditions may require treatment themselves and, in addition, may make the treatment of acute gout flares more problematic.” This is important as it may impact treatment outcomes; the authors noted that “on the one hand, risk factors such as obesity, hypertension or IHD are partly independent risk factors of flares; on the other, the prevalent co-existence of these factors also limits the use of the long-established standard therapy as many of these patients have relative or absolute contraindications. Some examples are the use of: NSAIDs in patients with peptic ulcer; of glucocorticoids in patients with diabetes; or colchicines in patients with gastrointestinal, renal, hepatic or cardiac disorders.”

They concluded that the results of this study of patients with incident gout “showed that a large proportion of patients with gout also have comorbid diseases. Obesity and hypertension were common comorbidities among patients who developed flares and a small minority had renal impairment. In addition, several lifestyle factors such as obesity and high alcohol intake were also related to risk of a gout flare and the patients should get advice and help for lifestyle modification. The fact that some of these underlying conditions that could impact on treatment are also independent risk factors for flares, further contribute to the complexity of prevention and treatment of gout flares.”