Chronic gout: epidemiology, disease progression, treatment and disease burden

Abstract

Background:

Gout is a painful and disabling inflammatory arthritis of increasing prevalence associated with hyperuricemia and the deposition of monosodium urate crystals in soft tissues and joints. Diagnosed gout cases have been estimated at 2.13% of the 2009 US population. The highest incidence occurs in the 65+ year age group, with males more than twice as likely to be afflicted as females.

Objective:

To present the epidemiology of chronic gout and to discuss its disease burden.

Methods:

This commentary is based on expert opinion and supplemented with published/presented information identified through PubMed and rheumatology associations.

Results:

The steady rise of diagnosed gout cases can generally be linked to an aging population with multiple comorbidities, the use of certain prescription medications, and changes in diet and lifestyle. Progression to chronic gout has numerous causes such as poor compliance with, ineffectiveness of, or inability to tolerate prescribed regimens. Despite the availability of urate-lowering therapies (ULT), patients may either have contraindications to them or may not adequately respond. Patients with high flare frequency, tophi, and the inability to maintain serum urate levels below 6 mg/dL with ULT can be categorized as having chronic gout that is refractory, with a substantial disease burden. Based on lack of therapeutic options for urate-lowering for patients with chronic gout refractory to conventional therapy, the economic burden of this small but substantial population contributes disproportionately to the overall economic burden of chronic gout. Recent availability of gout-specific ICD-9-CM codes capturing the cost intense and impactful aspects of the disease – flares and tophi – is likely contribute to understanding the full health economic burden in gout.

Conclusion:

The impact of chronic gout, especially if refractory to treatment, on functionality, productivity, quality of life and health care costs can be substantial and is deserving of future research.

Key words::

• Comorbidities
• Costs
• Epidemiology
• Gout
• Hyperuricemia
• Urate-lowering therapies
• Xanthine oxidase inhibitors

Transparency

Declaration of funding

Financial support for this manuscript was provided by Savient Pharmaceuticals, Inc., East Brunswick, NJ, USA.

Declaration of financial/other relationships

R.A.B. and J.E.S. have disclosed that they have served as consultants to Savient for this manuscript. N.L.E. has disclosed that he has received research support from Savient and is a consultant for both Savient and Takeda Pharmaceuticals North America. A.F. has disclosed that she is employed by Savient.

Some peer reviewers receive honoraria from CMRO for their review work. The peer reviewers of this paper have disclosed that they have no relevant financial relationships.

Acknowledgment

The authors thank Conny Burkett, RPh, Partner, Paradigm Consulting, Inc., for assistance with the medical writing and editing and Faith D. Ottery, MD, PhD, Savient, for her comments on the drafts of this manuscript.

Notes

* SF-36 is a registered trademark of Medical Outcomes Trust.