The economic burden of gout on an employed population

Clinical characteristics and risk factors associated with bone erosion in patients with tophi

INTRODUCTION

If a large amount of urate crystals is deposited in a joint cavity for an extended period of time, bone erosion will occur and gradually cause skeletal muscle necrosis and joint deformity. The aim of this study was to describe the clinical characteristics and factors associated with bone erosion in gout patients with tophi.

METHODS

A total of 210 gout patients with tophi were enrolled and divided into a bone erosion group (n = 135) and a non-bone erosion group (n = 75). Digital radiography (DR) was performed to detect bone erosion in the elbow, wrist, knee, ankle joints, interphalangeal and metatarsophalangeal joints. The clinical characteristics were recorded and compared between the two groups. Multivariate logistic regression analysis was conducted to explore the factors associated with bone erosion.

RESULTS

Compared with the non-bone erosion group, the bone erosion group had an older age, longer disease duration of gout and tophi, higher level of serum creatinine (sCr), higher proportion of drinking history and ulceration, and a lower glomerular filtration rate (GFR). Univariate logistic regression analysis results showed that sex, age, body mass index (BMI), gout duration, tophi duration, GFR, white blood cell (WBC) count, sCr level, smoking history, drinking history, and presence of ulceration were associated with bone destruction. Multivariable logistic regression analysis results indicated that tophi duration, drinking history, ulceration and sCr were positively and independently related to bone erosion.

CONCLUSIONS

Tophi patients with bone erosion presented different clinical characteristics. Tophi duration, drinking history, ulceration and sCr were associated with bone erosion in gout patients with tophi.

Gout Severity, Socioeconomic Status, and Work Absence: A Cross-Sectional Study in Primary Care

OBJECTIVE

To examine the association between gout severity and socioeconomic status (SES) and gout severity and work absence.

METHODS

Postal questionnaires were sent to adult patients who were registered with 20 general practices and who had consultations regarding gout or had been prescribed allopurinol or colchicine in the preceding 2 years. Gout severity was defined using the following proxy measures: number of attacks, history of oligoarticular/polyarticular attacks, disease duration, and allopurinol use. SES was defined using the English index of multiple deprivation (area level) and using self-reported educational attainment (individual level). Work absence was defined as taking time off from work in the past 6 months because of gout. Adjusted odds ratios (OR_adj ; 95% confidence intervals [95% CIs]) were calculated using logistic regression models (adjusted for age, sex, body mass index, gout severity, and comorbidities).

RESULTS

A total of 1,184 completed questionnaires were returned. The mean age of patients was 65.6 years, and 84% were male. Not having attended further education ("further education" is defined as attendance after the statutory minimum school-leaving age of 16 years) was associated with having had ≥2 gout attacks in the last year (OR_adj 0.54 [95% CI 0.36-0.81]) and oligoarticular/polyarticular attacks (OR_adj 0.72 [95% CI 0.50-1.05]). Lower area-level deprivation was associated with fewer attacks (≥2) (OR_adj 0.71 [95% CI 0.51-0.98]). Work absence was associated with having had ≥2 gout attacks in the last year (OR_adj 2.91 [95% CI 1.22- 6.92]), oligoarticular/polyarticular attacks (OR_adj 3.10 [95% CI 1.46-6.61]), and shorter disease duration (>18 years) (OR_adj 0.13 [95% CI 0.03-0.50]).

CONCLUSION

Gout severity was associated with individual-level deprivation, countering the historic and negative perception of gout as a "rich man's disease." The association of gout severity with work absence reinforces the argument for earlier urate-lowering therapy to prevent attacks from becoming frequent and debilitating.

The economic burden of uncontrolled gout: how controlling gout reduces cost

AIM

To evaluate the burden of uncontrolled gout by examining estimated costs and cost drivers.

MATERIALS AND METHODS

Data from the 2012 and 2013 US National Health and Wellness Survey (NHWS; 2012 NHWS, n = 71,157 and 2013 NHWS, n = 75,000) were utilized in this study. Based on self-reported gout diagnosis and gout symptoms, respondents were categorized into three groups: controlled gout (n = 344), uncontrolled gout (n = 2,215), and non-gout controls (n = 126,360). Chi-square tests and one-way analysis of variance (ANOVAs) were used to assess group differences on work productivity loss, healthcare resource utilization, and costs. Zero-inflated negative binomial regressions were used to assess the burden of uncontrolled gout on total costs after controlling for covariates.

RESULTS

Patients with uncontrolled gout had higher presenteeism, overall work impairment, activity impairment, and number of emergency department visits than those with controlled gout or controls. Overall, uncontrolled gout patients had both higher indirect and total costs compared to patients with controlled gout. After controlling for confounders, those with uncontrolled gout had higher total costs than controlled gout respondents and non-gout controls; there was no significant difference in total costs between patients with controlled gout and non-gout controls.

LIMITATIONS

Results were based on cross-sectional, self-reported data, making causal inferences more uncertain. Additionally, sample size was small for controlled-gout respondents. Lastly, sampling weights were not used, thus potentially limiting generalizability.

CONCLUSION

Gout can be an expensive condition, particularly if it is not properly controlled. This study provides support that controlling symptoms (e.g. flares) can reduce the economic and societal burden of gout. Therefore, more attention needs to be paid to effective management of gout symptoms.

Evaluation of healthcare costs and utilization for patients with gout: a population-based matched cohort study

OBJECTIVES

To better understand the economic burden of gout patients in Taiwan, a nationwide retrospective study was conducted to compare the healthcare costs and utilization between gout and gout-free patients.

METHODS

The Longitudinal Health Insurance Database (LHID) 2010 was used to identify gout cases and matched gout-free controls. Gout cases were defined as having (1) at least three instances of diagnoses of gout on medical claims, or (2) one diagnosis of gout with at least one gout-related pharmacy claim in 2011. A control cohort was matched with cases at a 3:1 ratio by age, gender, residential area, and the Charlson Comorbidity Index. All medical utilization and costs per patient within the 365 days following the index date were compared between cases and controls.

RESULTS

Out of 993,332 beneficiaries, a total of 21,376 matched gout patients met the gout inclusion criteria. Compared to controls, gout patients had more outpatient visits (mean = 31.2 vs 22.6), inpatient visits (mean = 1.7 vs 1.5), and ER visits (mean = 1.9 vs 1.7) (all p < .0001), as well as more outpatient costs (median = USD $634 vs $404), inpatient costs (median = USD $1330 vs $1254), and ER costs (median = USD $87 vs $89) (all p < .05).

CONCLUSION

Gout patients had higher medical utilization and costs than gout-free patients. In gout patients, all-cause and gout-related utilization were mostly outpatient visits, whereas most of the all-cause and gout-related costs were due to hospitalization. The study findings could be useful for future economic evaluations and healthcare resource allocation.

Work disability in gout: a population-based case–control study

Objectives

To examine the extent and cost of work disability among patients with gout compared with matched population controls and to analyse predictors of work disability.

Methods

A regional cohort study using data from Swedish national and regional registries from January 2000 through December 2012, including 4571 patients with gout of working age, with a first recorded diagnosis of gout in the years 2003–2009 and 22 482 population controls, matched by age, sex and place of residence. Differences in baseline characteristics (educational level, income, previous employment and comorbidities) and the number of work-loss days (absenteeism) due to sick leave and disability pension for 3 years after identification were calculated. Predictors for new-onset work absenteeism (>90 days/year) in a subset were determined by conditional logistic regression.

Results

Patients with gout (median age 53 years) had significantly more comorbidities, lower income and lower level of education than matched controls. The average work absentee rate during the 3-year follow-up period was higher among patients with gout than controls, 22% and 14%, respectively (P<0.0001). New-onset absenteeism was in multivariate analyses significantly predicted by gout (OR 1.47; 95% CI 1.23 to 1.75). Other variables independently related to new-onset absenteeism were education ≤12 years, previous unemployment and history of sick leave, in addition to several comorbidities (renal disease, cardiovascular disease, alcohol abuse and obesity).

Conclusions

Gout is associated with substantially higher work absenteeism and costs for society due to productivity loss, after adjusting for associated comorbidities and socioeconomic differences. Whether more intensive treatment of gout is cost-effective needs to be addressed in future studies.

Cost Comparison of Urate-Lowering Therapies in Patients with Gout and Moderate-to-Severe Chronic Kidney Disease

BACKGROUND

Patients with chronic kidney disease (CKD) are at increased risk for developing gout and having refractory disease. Gout flare prevention relies heavily on urate-lowering therapies such as allopurinol and febuxostat, but clinical decision making in patients with moderate-to-severe CKD is complicated by significant comorbidity and the scarcity of real-world cost-effectiveness studies.

OBJECTIVE

To compare total and disease-specific health care expenditures by line of therapy in allopurinol and febuxostat initiators after diagnosis with gout and moderate-to-severe CKD.

METHODS

A retrospective observational cohort study was conducted to compare mean monthly health care cost (in 2012 U.S. dollars) among gout patients with CKD (stage 3 or 4) who initiated allopurinol or febuxostat. The primary outcome was total mean monthly health care expenditures, and the secondary outcome was disease-specific (gout, diabetes, renal, and cardiovascular disease [CVD]) expenditures. Gout patients (ICD-9-CM 274.xx) aged ≥ 18 years with concurrent CKD (stage 3 or 4) were selected from the MarketScan databases (January 2009-June 2012) upon allopurinol or febuxostat initiation. Patients were followed until disenrollment, discontinuation of the qualifying study agent, or use of the alternate study agent. Patients initiating allopurinol were subsequently propensity score-matched (1:1) to patients initiating febuxostat. Five generalized linear models (GLMs) were developed, each controlling for propensity score, to identify the incremental costs (vs. allopurinol) associated with febuxostat initiation in first-line (without prior allopurinol exposure) and second-line (with prior allopurinol exposure) settings.

RESULTS

Propensity score matching yielded 2 cohorts, each with 1,486 patients (64.6% male, mean [SD] age 67.4 [12.8] years). Post-match, 74.6% of patients had stage 3 CKD; 82.9% had CVD; and 42.1% had diabetes. The post-match sample was well balanced on numerous comorbidities and medication exposures with the following exception: 50.0% of febuxostat initiators were treated in the second-line setting; that is, they had baseline exposure to allopurinol, whereas only 4.2% of allopurinol initiators had baseline exposure to febuxostat. Unadjusted mean monthly cost was $1,490 allopurinol and $1,525 febuxostat (P = 0.809). GLM results suggest that first-line febuxostat users incurred significantly (P = 0.009) lower cost than allopurinol users ($1,299 vs. $1,487), whereas second-line febuxostat initiators incurred significantly (P = 0.001) higher cost ($1,751 vs. $1,487). Febuxostat initiators in both settings had significantly (P < 0.001) higher gout-specific cost, due to higher febuxostat acquisition cost. Increased gout-specific cost in the first-line febuxostat cohort was offset by significantly (P < 0.001) lower CVD ($288 vs. $459) and renal-related cost ($86 vs. $216). There were no significant differences in either renal or CVD costs (adjusted) between allopurinol initiators treated almost exclusively in the first-line setting and second-line febuxostat patients.

CONCLUSIONS

Gout patients with concurrent CKD, initiating treatment with febuxostat in a first-line setting, incurred significantly less total cost than patients initiating allopurinol during the first exposure to each agent. Conversely, patients treated with second-line febuxostat following allopurinol incurred significantly higher total cost than patients initiating allopurinol. There was no significant difference in total cost between the agents across line of therapy. Although study findings suggest the potential for CVD and renal-related savings to offset febuxostat's higher acquisition cost in gout patients with moderate-to-severe CKD, this is the first such retrospective evaluation. Future research is warranted to both demonstrate the durability of study findings and to better elucidate the mechanism by which associated cost offsets occur.

DISCLOSURES

No outside funding supported this study. Turpin is an employee of Takeda Pharmaceuticals U.S.A. Mitri and Wittbrodt were employees of Takeda Pharmaceuticals U.S.A. at the time of this study. Tidwell and Schulman are employees of Outcomes Research Solutions, consultants to Takeda Pharmaceuticals U.S.A. All authors contributed to the design of the study and to the writing and review of the manuscript. All authors read and approved the final manuscript. Tidwell and Schulman collected the data, and all authors participated in data interpretation.

The Direct Economic Burden of Gout in an Elderly Canadian Population

Objective.

To estimate the direct healthcare cost and resource use from the public payer perspective between patients with incident gout and matched gout-free patients in Ontario.

Methods.

Patients with incident gout aged ≥ 66 with uninterrupted Ontario Health Insurance Plan (OHIP) coverage in the 1-year baseline period were included in the study. Patients with gout were indexed at first gout diagnosis or prescription over the study period April 1, 2008, to March 31, 2014. Gout-free patients with no gout diagnosis within history were matched (up to 5:1) to each patient with gout. Linked medical records were analyzed until end of study, death, or OHIP ineligibility. Bang and Tsiatis adjusted healthcare costs and resource use were compared using bootstrap p-values and 95% CI.

Results.

A total of 29,894 patients with gout and 148,231 gout-free patients were included in the study. Patients were 56% male, had a median Adjusted Clinical Group healthcare resource use band of moderate morbidity, and had a median age of 75–79 years. Baseline comorbidities were similar between groups except for renal disease. Analyzing 5-year total healthcare costs, patients with gout ($44,297) incurred a significantly higher average healthcare cost compared to gout-free patients ($33,965), for an incremental cost of $10,332 (95% CI $9617–$11,039; p < 0.01). Similar trends were observed in all individual healthcare component cost and use metrics.

Conclusion.

Following onset of gout, patients in Ontario incur significantly greater healthcare costs and resource use compared to matched gout-free patients. Alternative gout management strategies should be investigated to reduce the incremental burden of gout borne by the Ontario healthcare system.

The Human and Economic Burden of Difficult-to-Treat Gouty Arthritis

Gouty arthritis, one of the most painful and common forms of adult arthritis, is caused by monosodium urate crystal deposits in joints, most often in the lower extremities. Crystals trigger an inflammatory response leading to acute flares characterized by a rapid onset of pain, warmth, swelling, and redness in involved joints. Over time, continued monosodium urate crystal deposits and inflammation can lead to chronic tophaceous gout that result in bone erosion, progressing to joint destruction and significant disability. The goal of therapy in an acute gout flare is prompt and safe termination of pain and inflammation. Acute gouty arthritis is usually treated with nonsteroidal anti-inflammatory drugs, colchicine, or corticosteroids. However, for a growing number of patients, current standard treatments are ineffective or are contraindicated, largely due to the presence of comorbidities. Gouty arthritis can have a major negative impact of health-related quality of life, especially in patients with difficult-to-treat disease, as revealed by recent studies comparing health-related quality of life with that of the general population. Additionally, gouty arthritis also constitutes an important economic burden through absence from work and medical costs. This burden is even greater in patients with difficult-to-treat disease.

Cost-effectiveness analysis of febuxostat in patients with gout in Spain

Objectives Cost-effectiveness of febuxostat compared with allopurinol in the treatment of hyperuricemia in patients with gout. Methods Costs, clinical outcomes, and QALYs were estimated using a Markov model. Febuxostat 80 mg and 120 mg sequentially, used as first line and second line therapy, was compared with allopurinol 300 mg. Patients switched to the next treatment in the sequence according to a dichotomous response vs no response (target serum urate level < 6 mg/dl outcome) after 3 months of active treatment. A 3% discount rate and 5-year time horizon were applied.

PERSPECTIVE

National Health System. Results The addition of febuxostat to any therapeutic strategy was an efficient option, with incremental cost-effectiveness ratios (ICER) compared with allopurinol 300 mg ranging from €5268-€9737. Conclusions Febuxostat is a cost-effective treatment in Spain for the management of hyperuricemia in gout patients, with ICERs far below accepted Spanish efficiency thresholds (30 000€/QALY).

A Systematic Review of the Economic and Humanistic Burden of Gout

BACKGROUND

Gout is a chronic and inflammatory form of arthritis that is often overlooked despite the associated pain caused by acute flares and associated joint damage caused by the development of debilitating tophi. The increasing burden of gout, due to an aging population and the increased prevalence of known risk factors for hyperuricaemia, means that there is a continued need for new and effective urate-lowering treatments. The evaluation of these treatments will require a comprehensive and comparative evidence base describing the economic and humanistic burden of gout, taken from the perspective of patients, the healthcare system, and wider society.

OBJECTIVE

The objective of this study is to review and summarise the current evidence of the disease burden related to chronic gout, assessed in terms of both cost and health-related quality of life (HRQL), and to identify key factors correlated with an increased burden. The overall aim is to support the economic evaluation of new treatments for gout, and to highlight key data gaps that may need further study and exploration.

METHODS

Relevant literature dating from January 2000 to July 2014 was sourced through searches of the MEDLINE database via PubMed and The Cochrane Library. Articles published in English and reporting either the economic burden (cost) or the humanistic burden (HRQL/utility) of gout were identified, and key data were extracted and summarised, with key themes and data gaps identified and discussed.

RESULTS

Of the 323 studies identified, 39 met the inclusion criteria, of which 17 and 26 were relevant to the economic and humanistic burden, respectively. The economic burden of gout varied according to numerous factors, most notably serum urate acid levels and number of flares and tophi, resulting in higher healthcare resource use most often attributed to hospitalisation and inpatient stay. The incremental direct cost of gout has been suggested in the range of US$3165 to US$5515 (2004 and 2005 values, respectively) climbing to US$10,222 to US$21,467 (2008 values) per annum where patients are experiencing regular acute flares and have tophi present. The humanistic burden of gout was largely due to physical disability and pain resulting from chronic clinical manifestations. Short Form 6 dimensions (SF-6D) assessed utility weights are estimated at 0.53 for a patient with severe gout (≥3 flares/year and tophi) compared with 0.73 for an asymptomatic gout patient with serum acid levels <6 mg/dl.

CONCLUSIONS

The evidence confirms that gout has a growing overall prevalence and represents a significant burden in terms of both direct healthcare cost and HRQL outcomes. In light of this, effective urate-lowering treatments are likely to be valued if they can be clearly demonstrated to be both clinically effective and cost effective. Published data to support healthcare decision making in non-US countries with regards to treatments for gout are currently limited, which is a key limitation of the current evidence base. More research is also required to extend our understanding of the impact of gout on indirect costs, and a need also exists to develop a more comprehensive set of comparative HRQL utility assessments.

Pharmacokinetics, pharmacodynamics, and tolerability of LC350189, a novel xanthine oxidase inhibitor, in healthy subjects

Introduction

LC350189 is a novel selective xanthine oxidase inhibitor under clinical development for the management of hyperuricemia in gout patients. The aim of this study was to evaluate the pharmacokinetics, pharmacodynamics, and tolerability of the drug in healthy subjects.

Methods

A dose-block randomized, double-blind, active and placebo-controlled, single- and multiple-dosing study was conducted. A single ascending dose (SAD) study (10–600 mg) and a multiple ascending dose (MAD) study with once-daily doses (100–800 mg) for 7 days were conducted. Serial samples of blood and urine for pharmacokinetics/pharmacodynamics analysis were collected, and tolerability and adverse events were assessed throughout the study.

Results

Sixty-seven and 58 subjects were enrolled in the SAD and MAD studies, respectively. The mean C_max and AUC_last values increased with increasing doses, and exposure to LC350189 was dose proportional. The 24-hour mean serum uric acid (C_mean,24) decreased by 8.7%–31.7% (day 1) and 53.5%–91.2% (day 7) from baseline in the SAD and MAD studies, respectively, and the percentage decrease in C_mean,24 increased with higher doses.

Conclusion

LC350189 was well tolerated in the dose range of 10–800 mg. It lowered the serum and urine uric acid levels substantially in this dose range; the extent of the decrease in the serum uric acid level in the 200 mg dose group was similar or higher compared to that of febuxostat 80 mg group in the MAD study. It is expected that LC350189 could be safely administered once daily to patients with hyperuricemia or gout, leading to a sufficient decrease in uric acid levels.

Polymorphisms in GCKR, SLC17A1 and SLC22A12 were associated with phenotype gout in Han Chinese males: a case-control study

Background

Gout is a common arthritic disease resulting from elevated serum uric acid (SUA) level. A large meta-analysis including 28,141 individuals identified nine single nucleotide polymorphisms (SNPs) associated with altered SUA level in a Caucasian population. However, raised SUA level alone is not sufficient for the development of gout arthritis and most of these SNPs have not been studied in a Han Chinese population. Here, we performed a case–control association analysis to investigate the relationship between these SUA correlated SNPs and gout arthritis in Han Chinese.

Methods

A total of 622 ascertained gout p9atients and 917 healthy controls were genotyped. Genome-wide significant SNPs, rs12129861, rs780094, rs734553, rs742132, rs1183201, rs12356193, rs17300741 and rs505802 in the previous SUA study, were selected for our analysis.

Results

No deviation from the Hardy–Weinberg equilibrium was observed either in the case or control cohorts (corrected p > 0.05). Three SNPs, rs780094 (located in GCKR, corrected p = 1.78E⁻⁴, OR = 0.723), rs1183201 (located in SLC17A1, corrected p = 1.39E⁻⁷, OR = 0.572) and rs505802 (located in SLC22A12, corrected p = 0.007, OR = 0.747), were significantly associated with gout on allelic level independent of potential cofounding traits. While the remaining SNPs were not replicated. We also found significant associations of uric acid concentrations with these three SNPs (rs780094 in GCKR, corrected p = 3.94E⁻⁵; rs1183201 in SLC17A1, corrected p = 0.005; rs505802 in SLC22A12, corrected p = 0.003) and of triglycerides with rs780094 (located in GCKR, corrected p = 2.96E⁻⁴). Unfortunately, SNP-SNP interactions for these three significant SNPs were not detected (rs780094 vs rs1183201, p = 0.402; rs780094 vs rs505802, p = 0.434; rs1183201 vs rs505802, p = 0.143).

Conclusions

Three SUA correlated SNPs in Caucasian population, rs780094 in GCKR, rs1183201 in SLC17A1 and rs505802 in SLC22A12 were confirmed to be associated with gout arthritis and uric acid concentrations in Han Chinese males. Considering genetic differences among populations and complicated pathogenesis of gout arthritis, more validating tests in independent populations and relevant functional experiments are suggested in future.

Flare frequency, healthcare resource utilisation and costs among patients with gout in a managed care setting: a retrospective medical claims-based analysis

OBJECTIVES

For most gout patients, excruciatingly painful gout attacks are the major clinical burden of the disease. The goal of this study was to assess the association of frequent gout flares with healthcare burden, and to quantify how much lower gout-related costs and resource use are for those with infrequent flares compared to frequent gout flares.

DESIGN

Retrospective cohort study.

SETTING

Administrative claims data from a large US health plan.

PARTICIPANTS

Patients aged 18 years or above, and with evidence of gout based on medical and pharmacy claims between January 2009 and April 2012 were eligible for inclusion. Patient characteristics were assessed during a 12-month baseline period.

OUTCOME MEASURES

Frequency of gout flares, healthcare costs and resource utilisation were assessed in the 12 months following the first qualifying gout claim. Generalised linear models were employed to assess the impact of flare frequency on cost outcomes after adjusting for covariates.

RESULTS

102,703 patients with gout met study inclusion criteria; 89,201 had 0-1 gout flares, 9714 had 2 flares, and 3788 had 3+ flares. Average counts of gout-related inpatient stays, emergency room visits and ambulatory visits were higher among patients with 2 or 3+ flares, compared to those with 0-1 flares (all p<0.001). Adjusted annual gout-related costs were $1804, $3014 and $4363 in those with 0-1, 2 and 3+ gout flares, respectively (p<0.001 comparing 0-1 flares to 2 or 3+ flares).

CONCLUSIONS

Gout-related costs and resource use were lower for those with infrequent flares, suggesting significant cost benefit to a gout management plan that has a goal of reducing flare frequency.

Case study: a case of debilitating gout in the 1st metatarsophalangeal joint

Gout is a painful arthritic condition that affects many people worldwide. The disease has been associated with hyperuricaemia and life style risk factors such as obesity, alcohol intake, meat and seafood consumption. We present a case of a 67-year-old male with a history of gout, who attended the clinic with a painful 1st metatarsophalangeal joint, which had progressively worsened in pain, mobility and deformity in the last 20 years. Although lifestyle changes had been advised by the GP some years earlier such as a low purine based diet, management had only consisted of NSAID's, which had not significantly improved symptoms. Surgical excision of chalky white material from around the 1st metatarsophalangeal joint rendered the patient symptom free with increased mobility after 6 weeks. Histopathology confirmed the excised tissue as gouty tophus. Following this, the patient was placed on allopurinol, a xanthine oxidase inhibitor to prevent recurrent attacks. This case study highlights the importance of early recognition and prophylactic management in gout sufferers. In joints where the disease process is well-established surgical excision of the gouty tophus may help mitigate further disease progression, and restore quality of life to individuals.

The economic burden of gout: A systematic review

OBJECTIVE

Gout is a painful and disabling joint disease that constitutes the most common inflammatory arthritis in the US. To clarify the economic impact of gout, we systematically reviewed the literature on the direct and indirect costs associated with this disease.

METHODS

We conducted a literature search of MEDLINE, EMBASE, International Pharmaceutical Abstracts, NHS Economic Evaluation, and CINAHL databases to identify studies of gout and economics. We systematically reviewed published studies that met our inclusion criteria and extracted and summarized all relevant economic parameters. Reported costs were inflation-adjusted to 2013 US dollars (USD).

RESULTS

A total of 15 studies met all eligibility criteria. Three controlled studies reported all-cause total direct costs based on specific populations (i.e., $4733, $16,925, and $18,362 per capita among employed, elderly, and treatment-refractory gout populations, respectively, and $2562, $10,590, and $7188 among corresponding non-gout patients). Two additional studies, although uncontrolled, allowed for estimation of total all-cause direct costs in unselected gout populations ($11,080 and $13,170). Gout-related costs ranged from $172 to $6179, depending on population characteristics. Six studies reported positive associations of direct costs with SUA level, gout attack frequency, or presence of tophi. Four studies reported on indirect costs, which were estimated to be as high as $4341 USD.

CONCLUSION

The available data suggest that gout patients incur substantially greater direct and indirect costs as compared with gout-free individuals among elderly and treatment-refractory gouty patients, whereas the costs are considerably less among younger, employed gouty patients. Further, direct costs increased with worsening disease characteristics.

Cost of illness and determinants of costs among patients with gout

OBJECTIVE

To estimate costs of illness in a cross-sectional cohort of patients with gout attending an outpatient rheumatology clinic, and to evaluate which factors contribute to higher costs.

METHODS

Altogether, 126 patients with gout were clinically assessed. They completed a series of questionnaires. Health resource use was collected using a self-report questionnaire that was cross-checked with the electronic patient file. Productivity loss was assessed by the Work Productivity and Activity Impairment Questionnaire, addressing absenteeism and presenteeism. Resource use and productivity loss were valued by real costs, and annual costs per patient were calculated. Factors contributing to incurring costs above the median were explored using logistic univariable and multivariable regression analysis.

RESULTS

Mean (median) annual direct costs of gout were €5647 (€1148) per patient. Total costs increased to €6914 (€1279) or €10,894 (€1840) per patient per year when adding cost for absenteeism or both absenteeism and presenteeism, respectively. Factors independently associated with high direct and high indirect costs were a positive history of cardiovascular disease, functional limitations, and female sex. In addition, pain, gout concerns, and unmet gout treatment needs were associated with high direct costs.

CONCLUSION

The direct and indirect costs-of-illness of gout are primarily associated with cardiovascular disease, functional limitations, and female sex.

Imaging in gout: A review of the recent developments

Gout is a common inflammatory arthritis and is caused by accumulation of monosodium urate crystals in joints and soft tissues. Apart from joint damage, untreated gout is associated with cardiovascular and renal morbidity. Gout, whilst in principle considered to be well understood and simple to treat, often presents diagnostic and management challenges, with evidence to suggest that it is often inadequately treated and poor compliance is a major issue. Imaging tools can aid clinicians in establishing the correct diagnosis, when histological crystal diagnosis is unable to be established, and also assess the burden of inflammatory and structural disease. Imaging can also be used to monitor treatment response. The imaging techniques that currently have a role in the imaging of gout include conventional radiography, ultrasound, computed tomography, dual energy computed tomography, magnetic resonance imaging and nuclear medicine. Despite the lack of major technological advances in imaging of gout in recent years, scientific studies of existing imaging modalities have improved our understanding of the disease, and how to best utilize imaging techniques in the clinical setting.

Cost-effectiveness of febuxostat in chronic gout

Our objective was to evaluate data on the cost-effectiveness of febuxostat compared with standard clinical practice with allopurinol in patients with gout that was presented to the Scottish Medicines Consortium (SMC) in 2010. A Markov health-state model estimated the direct health-related costs and clinical benefits expressed as quality-adjusted life-years (QALYs). Adults with chronic gout and established hyperuricaemia received treatment sequences of daily doses of allopurinol 300 mg alone or allopurinol 300 mg followed by febuxostat 80 mg/120 mg. The proportion of patients achieving the target serum uric acid (sUA) level of less than 6 mg/dl (0.36 mmol/l) was linked to the utility per sUA level to generate an incremental cost-effectiveness ratio (ICER). Second-line therapy with febuxostat 80 mg/120 mg versus with allopurinol alone resulted in an ICER of £3,578 per QALY over a 5-year time horizon. Additional univariate analyses showed that ICER values were robust and ranged from £2,550 to £7,165 per QALY when different parameters (e.g., low- and high-dose allopurinol titrations and variations in treatment-induced flare rates) were varied. Febuxostat reduces sUA below the European League Against Rheumatism target of 0.36 mmol/l (6 mg/dl) in significantly more patients with gout than allopurinol in its most frequently prescribed dose of 300 mg per day. The SMC accepted febuxostat as cost-effective as a suitable second-line option for urate-lowering therapy for the treatment of patients with chronic hyperuricaemia in conditions where urate deposition has already occurred (including a history or presence of tophus and/or gouty arthritis) when treatment with allopurinol was inadequate, not tolerated, or contraindicated.

A revised estimate of the burden of illness of gout

Background

Gout is a chronic, inflammatory arthritis characterized by painful and debilitating acute/episodic flares. Until recently, gout has been regarded as a minor medical problem, in part because the associated economic burden has not been appreciated. Previous literature on this subject focused on the costs associated with acute episodes of gout rather than on the long-term medical and economic implications of this chronic disorder.

Objective

Our aim was to estimate the current impact of gout in the United States with respect to disability and economic costs.

Methods

The following data sources were used: published data on the incremental economic burden of gout; statistics from the US Census Bureau and the US Bureau of Labor Statistics; and recent epidemiological and clinical literature concerning the course, treatment, and outcomes of the disease. Disability is expressed as days of lost productivity. Charges for gout-related treatments were used as direct cost inputs.

Results

Gout affects an estimated 8 million Americans, among whom those working have an average of almost 5 more absence days annually than workers without gout. On average, the incremental annual cost of care for a gout patient is estimated at >$3000 compared with a nongouty individual. Even though comorbidities common in gout patients account for a portion of this increased economic burden, the total annual cost attributable to gout patients in the United States is likely in the tens of billions of dollars and comparable to those of other major chronic disorders, such as migraine and Parkinson’s disease.

Conclusions

The economic burden of gout is most readily assessable in patients whose acute arthritic flares result in emergency department visits, bedridden days, and episodic loss of productivity. Chronic progression of the disease can also result in long-term impairment of function and health-related quality of life, but the contribution of chronic gout to the economic burden is more difficult to quantitate because gout is frequently associated with serious cardiovascular, metabolic, and renal comorbidities. Recent demonstration that successful gout management can reverse functional deficits in many chronic gout patients, however, supports the views that chronic gout contributes substantially to the medical and thus economic costs of these patients and that early and aggressive efforts to improve gout outcomes are likely to reduce the associated economic burden.

The Gout Assessment Questionnaire 2.0: cross-cultural translation into Dutch, aspects of validity and linking to the International Classification of Functioning, Disability and Health

OBJECTIVES

The Gout Assessment Questionnaire 2.0 (GAQ2.0) is a disease-specific patient-reported outcome measure for gout that distinguishes five different subscales and comprises overall 31 questions. The aims of this study were to translate the GAQ2.0 into Dutch and to test clinimetric properties.

METHODS

Recommendations for translation and cross-cultural adaptation were followed and no cultural adaptations were needed. The resulting Dutch GAQ2.0 was administered to patients registered at the rheumatology outpatient clinic diagnosed with gout. Internal consistency was tested using Cronbach's α, reliability using intraclass correlation coefficient (ICC), content validity by linkage to the International Classification of Functioning, Disability and Health (ICF) and construct validity by correlating the subscales of the GAQ2.0 with the HAQ disability index (HAQ-DI) and 36-item Short Form Health Survey (SF-36).

RESULTS

A total of 126 patients [106 (84%) male, mean age 66.6 years (s.d. 10.4), mean disease duration 11.2 years (s.d. 10.6)] completed a number of questionnaires, including the GAQ2.0, HAQ-DI and SF-36, and underwent a clinical examination. Internal consistency was sufficient (Cronbach's α = 0.83-0.94), except for the subscale gout medication side effects (Cronbach's α = 0.51). Test-retest reliability was good (ICCs 0.73-0.86) for all subscales, but moderate for the subscale unmet gout treatment need (ICC 0.56). Gout impact (GI) subscale scores showed only weak to moderate correlations with HAQ-DI and SF-36, but stronger emphasis on the emotional consequences of gout. Also, it correlated better with gout-specific outcomes such as the number of gout flares and pain.

CONCLUSION

The Dutch GAQ2.0 shows sufficient evidence of validity to assess disease-specific functioning and health in patients with gout and seems to capture different aspects than those represented in the HAQ and SF-36.

Annual incremental health benefit costs and absenteeism among employees with and without rheumatoid arthritis

OBJECTIVE

To assess the impact of rheumatoid arthritis (RA) on absence time, absence payments, and other health benefit costs from the perspective of US employers.

METHODS

Retrospective regression-controlled analysis of a database containing US employees' administrative health care and payroll data for those who were enrolled for at least 1 year in an employer-sponsored health insurance plan.

RESULTS

Employees with RA (N = 2705) had $4687 greater average annual medical and prescription drug costs (P < 0.0001) and $525 greater (P < 0.05) indirect costs (because of sick leave, short- and long-term disability, and workers' compensation absences) than controls (N = 338,035). Compared with controls, the employees with RA used an additional 3.58 annual absence days, including 1.2 more sick leave and 1.91 more short-term disability days (both P < 0.0001).

CONCLUSION

Employees with RA have greater costs across all benefits than employees without RA.

Gout impacts on function and health-related quality of life beyond associated risk factors and medical conditions: results from the KING observational study of the Italian Society for Rheumatology (SIR)

Introduction

Gout is the most prevalent arthritis and significantly impacts on function and quality of life. Given that gout associates with disabling comorbid conditions, it is not clear whether such a complex of diseases accounts for the increased disability or if gout may play a role by itself. This study aims to evaluate the specific influence of gout and disease-related features on functional disability and health-related quality of life (HRQoL) in patients with gout followed in rheumatology clinics.

Methods

A random sample of patients was drawn from clinical registries of 30 rheumatology clinics across Italy. Sociodemographic, general health and gout-specific variables were collected. Functional disability and HRQoL were assessed by the health assessment questionnaire (HAQ) and the Physical and Mental Component Summary scores (PCS and MCS) of the Short Form-36 (SF-36). Crude and adjusted ordinal logistic and linear regression models were applied to investigate the specific contribution of different variables on HAQ and SF-36 scores. Results are presented as odds ratio (OR) or mean difference (MD) and 95% confidence intervals.

Results

Out of 446 patients with gout, 90% were males with a mean age of 63.9 years and median disease duration of 3.8 years; the majority of patients were overweight or obese, and with several comorbidities; 21.1% showed at least moderate disability; the PCS score was significantly lower than expected age- and gender-matched samples in the general population, while MCS score was not. After adjusting for potential sociodemographic and general-health confounders, gout-specific variables significantly impacted on HAQ, including polyarticular involvement OR 3.82 (1.63, 8.95), presence of tophi OR 1.92 (1.07, 3.43) and recent attacks OR 2.20 (1.27, 3.81). Consistent results were found for PCS. The impairment of PCS compared to the general population was limited to patients with features of chronic gout. MCS was only affected by recent attacks (MD -2.72 [-4.58, -0.86]) and corticosteroid treatment (-3.39 [-5.30,-1.48]).

Conclusions

The data from the KING study confirm that gout impacts on disability and provide evidence for an independent association of gout and gout-related features with functional outcome and HRQoL. This result supports the need to improve specific treatment in gout.

The effect of gout on health-related quality of life, work productivity, resource use and clinical outcomes among patients with hypertension

Although gout has been found to be associated with health-related quality of life (HRQoL), few studies have examined the burden of gout in the presence of concomitant cardiometabolic conditions. The present study evaluated the effect of gout on HRQoL and work productivity among patients with hypertension. Data from the 2010 National Health and Wellness Survey were obtained for respondents ≥18 years of age who had self-reported, physician-diagnosed hypertension or blood pressure levels ≥140/90 mmHg (≥130/80 mmHg for those with physician-diagnosed diabetes or chronic kidney disease). Bivariate analysis was used to evaluate differences between patients with and without self-reported comorbid gout. Generalized linear models were used to evaluate differences in productivity (using the Work Productivity and Activity Impairment scale) and HRQoL (using the physical component summary [PCS], mental component summary and health utilities from the SF-12v2 health survey). As uric acid levels may influence other organ systems, core modeling did not include comorbidities other than osteoarthritis and depression as covariates. Sensitivity analyses were controlled for the Charlson comorbidity index. A total of 22,686 patients with self-reported hypertension met study eligibility requirements. Of these, 4.51% reported having gout. These patients were older, more likely to be male and have insurance through Veteran Affairs (all p-values < 0.05). Patients with comorbid gout reported lower levels of mental component summary scores (47.25 vs 48.93), PCS scores (39.06 vs 43.78) and health utilities (0.68 vs 0.73; all p-values < 0.05). For both PCS and health utilities, differences between groups exceeded clinically meaningful cutoffs. Sensitivity analyses conducted on PCS and health utilities uncovered slightly smaller, but statistically significant and clinically meaningful, effects (p-values < 0.05). The effect of gout on overall work impairment (23.33 vs 17.40% with and without comorbid gout, respectively) remained after controlling for the Charlson comorbidity index. Significantly greater impairment in daily activities (38.96 vs 28.32%; p < 0.05) was also observed among patients with comorbid gout. Results demonstrate that gout has significant and clinically meaningful impact on work productivity, physical HRQoL and utilities independent of other health conditions.

The Work Instability Scale predicts absenteeism in people with gout and suggests a higher risk for those in manual occupations

BACKGROUND

Gout occurs in working-age people and may be associated with significant work disability. There are no longitudinal studies to examine risk factors for work disability in people with gout.

OBJECTIVES

The purpose of this study was to determine the validity of the Work Instability Scale (WIS) in patients with gout and to see if baseline WIS scores predicted future work absences.

METHODS

We conducted a longitudinal, cohort study with patients who had gout for less than 10 years. Sick leave over the previous 3 months was recorded by patient recall at baseline and at 12 months. Self-report health status measures and disease characteristics including C-reactive protein and serum urate were measured at baseline. Work Instability Scale scores were fitted to a Rasch model, and nonparametric statistics were used to determine associations between disease features or future sick leave and WIS scores.

RESULTS

One hundred seventy-six participants were recruited, and follow-up information was available for 133 (76%). The WIS instrument showed satisfactory internal, construct, and predictive validity. Participants in nonmanual occupations had lower (better) WIS scores (median, 0 vs. 5.5; P < 0.001). Only 7% of working participants reported any sick leave in the 3 months before the 12-month follow-up. Work Instability Scale scores were associated with future sick leave: a cutoff of 4.5 was found to have the best combined sensitivity (88%) and specificity (72%) for predicting at least 1 day of sick leave.

CONCLUSIONS

The WIS instrument can identify people with gout who have a higher risk of future work disability and might be a useful guide to targeted vocational counseling or job modification, especially in people in manual occupations. However, further research is required to confirm these findings and to refine the instrument for optimal performance in this population.

Comorbidity burden, healthcare resource utilization, and costs in chronic gout patients refractory to conventional urate-lowering therapy

Patients with chronic gout refractory to conventional urate-lowering therapy have high rates of flares and incidence of tophi, which impose a significant disease and potentially economic burden. This study examined healthcare resource use and costs stratified by disease burden. Adult patients diagnosed with gout (ICD-9-CM:274.xx) and having had ≥3 flares defined by clinical surrogates within a 12-month period were selected for the case cohort from the Thomson MarketScan databases (2003/Q3-2008/Q3). Only patients who had received allopurinol treatment and a diagnosis of tophi (ICD-9-CM:274.8x) at any time before the first flare (index date) or within 12 months postindex were included and were matched in a 1:1 ratio with control gout-free subjects. The comorbidity burden, healthcare resource use, and annual healthcare costs (2008 US$) in the 12-month postindex period were compared between both cohorts using regression models adjusted for demographic characteristic and stratified for patients with ≥6 flares. A total of 679 gout patients met the inclusion criteria for the study and had a higher prevalence of comorbidities than their matched controls. Gout cohort had a significantly higher incidence of emergency room, hospitalizations, outpatient visits, and other medical services than did their matched controls (all comparisons, uncorrected P < 0.01). After adjusting for baseline characteristics, the refractory gout cohort incurred an incremental total annual healthcare cost of $10,222 where 40% of the annual medical cost was for gout-related care compared with control cohort (P < 0.01). Patients with refractory gout have a significant economic burden compared with a gout-free population.

Genome-wide association analyses identify 18 new loci associated with serum urate concentrations

Elevated serum urate concentrations can cause gout, a prevalent and painful inflammatory arthritis. By combining data from >140,000 individuals of European ancestry within the Global Urate Genetics Consortium (GUGC), we identified and replicated 28 genome-wide significant loci in association with serum urate concentrations (18 new regions in or near TRIM46, INHBB, SFMBT1, TMEM171, VEGFA, BAZ1B, PRKAG2, STC1, HNF4G, A1CF, ATXN2, UBE2Q2, IGF1R, NFAT5, MAF, HLF, ACVR1B-ACVRL1 and B3GNT4). Associations for many of the loci were of similar magnitude in individuals of non-European ancestry. We further characterized these loci for associations with gout, transcript expression and the fractional excretion of urate. Network analyses implicate the inhibins-activins signaling pathways and glucose metabolism in systemic urate control. New candidate genes for serum urate concentration highlight the importance of metabolic control of urate production and excretion, which may have implications for the treatment and prevention of gout.

Resource use and economic impact of patients with gout: a multicenter, population-wide study

OBJECTIVE

To determine the use of resources and economic impact of patients with gout at the population level.

PATIENTS AND METHODS

Observational design analysing records belonging to 6 primary care centers and 2 hospitals. We included patients' ≥18 years with an acute episode of gout over the years 2003-2007. Patient follow-up was 2 years. It produced two study groups: patients with 1-2 attacks/acute recurrences and 3 or more events. Main variables were: demographic, co-morbidity, metabolic syndrome (MS), and resource use and health/non-health costs.

STATISTICAL ANALYSIS

logistic regression-model ANCOVA, P<.05.

RESULTS

3,130 patients with gout were included. Prevalence: 3.3%, mean age: 55.8 years male: 81.1%. Groups were distributed as follows: 68.4% had 1-2 acute attacks and 31.6% with 3 or more, P<.001. The prevalence of MS was 28.8% (confidence interval [CI] 95% CI 27.2 to 30.4%). The average/unit cost was € 2,228.6 (direct costs: 96.9%), 90.8% in primary care (visits: 23.5%; drugs: 57.7%). For groups, the average corrected model/unit total cost per patient was € 2,130.6 vs. € 2,605.4, respectively (P<.001). In all cost components, the results were higher in the group with ≥ 3 attacks. The subgroup of diabetic patients (N=641, 20.5%) had a higher cost (€ 3,124.8€ vs. € 1,997.8, P<.001).

CONCLUSIONS

Gout is associated with substantial morbidity, presence of MS and resource consumption. The study provides useful data on the cost of the disease; the costs of outpatient follow up is the highest.

Tophi and frequent gout flares are associated with impairments to quality of life, productivity, and increased healthcare resource use: Results from a cross-sectional survey

Background

The prevalence of gout is increasing, and most research on the associated burden has focused on serum urate (sUA) levels. The present study quantifies the impact of the presence of tophi and frequency of acute gout attacks on health-related quality of life (HRQOL), productivity, and healthcare resource utilization.

Methods

Patients with self-reported gout (n = 620; 338 in US and 282 across France, Germany, and UK) were contacted based on inclusion in the 2010 US and EU National Health and Wellness Surveys (Kantar Health) and the Lightspeed Research ailment panel. Respondents were categorized into mutually-exclusive groups based on number of gout flares experienced in the past 12 months (0/don’t recall, 1–2, 3, 4–5, 6+), current presence of tophi (none, 1+, or not sure), and sUA level awareness (yes, no). HRQOL (SF-12v2), healthcare provider visits in the last 6 months, and work productivity and activity impairment (WPAI) were compared across groups.

Results

Most patients were males, mean age of 61 years, who reported experiencing at least one acute gout flare in the past 12 months, and 12.3% (n = 76) reported presence of tophi. Among the 27.7% (n = 172) of patients who were aware of their sUA levels, higher sUA was associated with more flares and tophi. Decreased HRQOL was associated with more frequent flares and presence of tophi. In multivariable models predicting outcomes based on presence of tophi and number of flares, both flares (≥4) and tophi (≥1) were associated with HRQOL decrements on physical and mental component summary scores and health utilities (all p < 0.05), after adjustment for age, gender, and time since diagnosis. Flares were also associated with greater activity impairment.

Conclusions

Impairments associated with gout flares and presence of tophi, across patients in the US and EU, underscore the importance of effective management of this potentially curable condition.

Comparison of patient characteristics and gout-related health-care resource utilization and costs in patients with frequent versus infrequent gouty arthritis attacks

OBJECTIVE

To examine the association between frequent gouty arthritis and the presence of absolute/relative contraindications to gout therapies, and health-care expenditure associated with frequent gouty arthritis.

METHODS

This retrospective study used administrative claims to identify patients with gouty arthritis between 1 July 2005 and 30 June 2010. Patients with ≥3 yearly gouty arthritis attacks (frequent gout) were matched 1:2 to patients with <3 yearly attacks (infrequent gout). Absolute and relative contraindications to gout medications were evaluated based on product labelling. Negative binomial regression and generalized linear models with logarithmic transformation were used for multivariate analysis of overall and gout-related health-care use and cost.

RESULTS

Mean patient age was 58 years (n = 15 669) and 77% were men. Compared with patients with infrequent gout, those with frequent gout had higher rates of absolute/relative contraindications to NSAIDs (91.5% vs 78.7%, P < 0.0001), corticosteroids (96.4% vs 87.3%, P < 0.0001), allopurinol (51.0% vs 41.2%, P < 0.0001) and probenecid (13.4% vs 9.4%, P < 0.0001). Mean gout-related costs were $889 for frequent gout vs $210 for infrequent gout (P < 0.0001) and all-cause direct costs were $10 913 for frequent vs $10 685 for infrequent gout (P = ns). Mean all-cause outpatient visits among patients with comorbidities compared with those without were 25.8 vs 11.8 among frequent and 19.7 vs 9.0 among infrequent (both P < 0.001) groups. Gout-related costs were higher among frequent gout patients with comorbidities than those without comorbidities ($886 vs $513, P = 0.03).

CONCLUSION

Patients with frequent gouty arthritis are likely to have absolute and/or relative contraindications to gout medications and higher gout-related treatment costs.

Evaluation of health care costs and utilization patterns for patients with gout

BACKGROUND

The prevalence of gout has been increasing. Serum uric acid (sUA) levels ≥6 mg/dL have been associated with high morbidity and increased health care utilization.

OBJECTIVE

To assess the costs and patterns of health care resource utilization for patients with gout, categorized into 3 cohorts based on sUA levels.

METHODS

We retrospectively analyzed laboratory, pharmacy, and medical service claims data (January 2005 to June 2010) for patients ≥18 years old. Inclusion criteria were at least 2 sUA levels and at least 1 primary gout diagnosis (International Classification of Disease-9th revision code 274.xx), and/or at least 1 prescription for gout-specific medications. Outcomes including costs, health care resource utilization, and medication adherence and persistence were assessed for the 1-year postindex period and summarized for the 3 cohorts based on sUA levels: <6 mg/dL, 6 to 8.99 mg/dL, and ≥9 mg/dL. Costs were adjusted based on preindex utilization and baseline characteristics.

RESULTS

Three hundred fifty-two patients met the inclusion criteria: cohort 1 (sUA <6 mg/dL), n = 38, mean age 59 years; cohort 2 (sUA 6-8.99 mg/dL), n = 231, mean age 61 years; and cohort 3 (sUA ≥9 mg/dL), n = 83, mean age 62 years. Mean adjusted gout-related health care costs were $332, $353, and $663, respectively (P <0.05); mean adjusted all-cause health care costs were $11,365, $11,551, and $14,474, respectively, for the 3 cohorts (P <0.05). sUA levels were positively associated with the percent of patients who had at least 1 hospitalization and the mean number of hospitalizations and emergency department visits (P < 0.05). Significantly more patients with sUA <6 mg/dL achieved adherence rates of ≥80% and had a longer mean duration of continuous treatment compared with patients with sUA between 6 and 8.99 mg/dL or ≥9.0 mg/dL (P <0.05).

CONCLUSIONS

Patients with high levels of sUA had higher gout-related and all-cause health care costs, more all-cause hospitalizations, and emergency department visits, but they also exhibited poorer adherence and persistence.

A new perspective on the pharmacoeconomics of colchicine

BACKGROUND

Gout is a common inflammatory arthritis that affects ∼4% of the US population. Most patients with gout are >50 years of age and have multiple comorbidities. Gout is caused by the deposition of monosodium urate crystals in joints secondary to hyperuricemia. Gout typically presents as an acute painful inflammation (flare) involving one or more joint. Left untreated it can progress into a more chronic polyarthritis. Acute gout flare treatment options include colchicine, non-steroidal anti-inflammatory drugs (NSAIDs), and corticosteroids. The safety and efficacy of colchicine, especially in the presence of comorbidity and potential contraindications, has only recently been systematically investigated.

METHODS

Through the use of a systematic computer-based literature analysis, this pharmacoeconomic review evaluated costs, risks, and benefits of Colcrys (colchicine) compared with other treatments for gout in the US.

RESULTS

Both colchicine and NSAIDs are historically associated with gastrointestinal (GI) adverse events (AEs). Colchicine has very low risk for AEs, even in patients with GI disorders; whereas, NSAIDS are contraindicated in patients with GI disorders, renal insufficiency, and heart failure. The monthly cost of treating 100 patients with Colcrys was $33,100 compared with $3000 for NSAIDs. However, hospitalization for GI complications (1.8%) and heart failure (1.9%) is common with NSAIDs and can increase the monthly cost of treating 100 patients with NSAIDs to $161,000, considering $15,000-20,000 per day of hospitalization.

CONCLUSIONS

Considering high costs associated with treating patients with gout, it seems prudent to choose the treatment with greatest benefit, lowest cost, and least risk. Despite higher cost per dose, colchicine appears to be more cost effective for management of gout flares than NSAIDs.

Canakinumab relieves symptoms of acute flares and improves health-related quality of life in patients with difficult-to-treat Gouty Arthritis by suppressing inflammation: results of a randomized, dose-ranging study

INTRODUCTION

We report the impact of canakinumab, a fully human anti-interleukin-1β monoclonal antibody, on inflammation and health-related quality of life (HRQoL) in patients with difficult-to-treat Gouty Arthritis.

METHODS

In this eight-week, single-blind, double-dummy, dose-ranging study, patients with acute Gouty Arthritis flares who were unresponsive or intolerant to--or had contraindications for--non-steroidal anti-inflammatory drugs and/or colchicine were randomized to receive a single subcutaneous dose of canakinumab (10, 25, 50, 90, or 150 mg) (N = 143) or an intramuscular dose of triamcinolone acetonide 40 mg (N = 57). Patients assessed pain using a Likert scale, physicians assessed clinical signs of joint inflammation, and HRQoL was measured using the 36-item Short-Form Health Survey (SF-36) (acute version).

RESULTS

At baseline, 98% of patients were suffering from moderate-to-extreme pain. The percentage of patients with no or mild pain was numerically greater in most canakinumab groups compared with triamcinolone acetonide from 24 to 72 hours post-dose; the difference was statistically significant for canakinumab 150 mg at these time points (P < 0.05). Treatment with canakinumab 150 mg was associated with statistically significant lower Likert scores for tenderness (odds ratio (OR), 3.2; 95% confidence interval (CI), 1.27 to 7.89; P = 0.014) and swelling (OR, 2.7; 95% CI, 1.09 to 6.50, P = 0.032) at 72 hours compared with triamcinolone acetonide. Median C-reactive protein and serum amyloid A levels were normalized by seven days post-dose in most canakinumab groups, but remained elevated in the triamcinolone acetonide group. Improvements in physical health were observed at seven days post-dose in all treatment groups; increases in scores were highest for canakinumab 150 mg. In this group, the mean SF-36 physical component summary score increased by 12.0 points from baseline to 48.3 at seven days post-dose. SF-36 scores for physical functioning and bodily pain for the canakinumab 150 mg group approached those for the US general population by seven days post-dose and reached norm values by eight weeks post-dose.

CONCLUSIONS

Canakinumab 150 mg provided significantly greater and more rapid reduction in pain and signs and symptoms of inflammation compared with triamcinolone acetonide 40 mg. Improvements in HRQoL were seen in both treatment groups with a faster onset with canakinumab 150 mg compared with triamcinolone acetonide 40 mg.

TRIAL REGISTRATION

clinicaltrials.gov: NCT00798369.

Work productivity loss due to flares in patients with chronic gout refractory to conventional therapy

OBJECTIVE

Joint pain and swelling during gout flares may lead to considerable morbidity and disability, having an impact on patient work productivity and social participation. The objective of this study was to assess how gout flares affect these activities in patients with chronic gout refractory to conventional therapy.

METHODS

A 1-year prospective observational study was conducted among patients with symptomatic disease in the United States in 2001. Inclusion criteria required patients (1) to be age 18 years or older, (2) to have documented, crystal-proven gout, (3) to have symptomatic gout, and (4) to be intolerant or unresponsive to conventional therapy, reflected by SUA ≥ 6.0 mg/dL. Patients were evaluated every 2 months. At each visit, patients completed a gout diary, which included number of flares experienced, duration and severity of each flare, and whether the flare caused: (1) work loss, (2) missed appointments or social events, or (3) impairment of self-care activities. The Short-Form Health Survey (SF-36) was also completed each visit.

RESULTS

Analyses were restricted to those who completed the first 6 months of the study (n = 81). Mean number of flares per patient per year was 8.8. Of the patients who were <65 years, 78% reported at least 1 work day lost due to a gout attack during the year. Mean annual work day loss for those <65 years was 25.1 days. A total of 545 of patients reported at least one flare per year that impaired social activities, with a mean of 17.1 social days lost and 52% reported at least one flare per year that compromised normal self-care activities, with a mean of 16.9 days impairment. Correlations between the diary reports and activity-related questions from the SF-36 were significantly positive.

LIMITATIONS

The study is limited by small sample size, lack of reference group, and inability to explicitly collect employment information. Age under 65 years was used as a proxy for employment eligibility.

CONCLUSION

Flares in patients with chronic gout refractory to conventional therapy significantly affect patient work productivity and social activities.

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

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.

Health care utilization in patients with gout

OBJECTIVE

To study health care utilization patterns in patients with gout.

METHODS

In a gout population from primary care and rheumatology clinics in 3 U.S. metropolitan cities, we collected data on gout-related utilization (primary care, rheumatology, urgent care, emergency room, and other) in the past year. We evaluated the association of comorbidities, age, gender, gout characteristics (time since last gout attack and tophi), and gout severity ratings (mean of serum uric acid, patient-rated, and physician-rated gout severity) and with emergency/urgent care and primary care utilization using regression and correlation analyses.

RESULTS

Of the 296 patients who reported visiting at least 1 type of health practitioner for gout in the past year, the percentage of patients utilizing the service at least once and annual utilization rates among utilizers were as follows: primary care physician, 60%, 3.0 ± 3.4; nurse practitioner/physician assistant, 26%, 2.7 ± 2.5; rheumatologist, 51%, 3.7 ± 5.7; urgent care, 23%, 2.1 ± 2.2; emergency room, 20%, 2.0 ± 1.7; and hospitalization, 7%, 2.1 ± 1.4. Higher overall gout severity was associated with greater use of each resource type and with overall gout-related utilization. Nonemergency/nonurgent care utilization (primary care physician, nurse practitioner, physician's assistant, and rheumatologist for gout) was the strongest predictor of gout-related emergency/urgent care utilization. Patients with more comorbidities had greater gout-related primary care utilization.

CONCLUSIONS

Overall gout severity was associated with all types of gout-related utilization. This may help to screen high utilizers for targeted behavioral and therapeutic interventions. Having a higher number of comorbid conditions was a risk factor for higher gout-related primary care utilization.

Febuxostat: the evidence for its use in the treatment of hyperuricemia and gout

Introduction:

Gout is a common and disabling cause of arthritis in middle-aged and elderly populations, with its main predisposing factor being hyperuricemia (serum urate > 6.8 mg/dL). Options for treatment of chronic gout until 2008 were allopurinol, a xanthine oxidase inhibitor, and the group of drugs known as uricosurics that stimulate the renal excretion of uric acid. A proportion of patients, including some with chronic kidney disease and solid organ transplantations, could not be treated with the those therapies because of intolerance, drug interactions, or adverse events. Febuxostat is a nonpurine xanthine oxidase inhibitor, recently approved in Europe and the United States for the treatment of chronic gout.

Aim:

To review the clinical evidence (phase II and III studies) of the effectiveness and safety of febuxostat for treatment of hyperuricemia and gout.

Evidence review:

Febuxostat, at doses ranging from 40 to 240 mg/day, is efficacious in reducing serum urate in patients with hyperuricemia and gout, comparing favorably with fixed doses of allopurinol in that respect. Early safety signals with respect to liver test abnormalities and cardiovascular outcomes have not been confirmed in recent large prospective trials but need to be further monitored.

Clinical potential:

Given its low cost and extensive clinical experience, allopurinol will likely remain the first-line drug for management of hyperuricemia and gout. Febuxostat may provide an important option in patients unable to use allopurinol, those with very high serum urate levels, or in the presence of refractory tophi.

An employer perspective on annual employee and dependent costs for pediatric asthma

BACKGROUND

The burden of pediatric asthma on parents' health care costs is not well described.

OBJECTIVE

To evaluate direct and indirect health care costs of employees with children with asthma (asthma cohort) compared with employees with children without asthma (control cohort).

METHODS

Retrospective analysis of 2001-2007 employer data including employee medical and pharmacy claims, payroll, work absence, demographics, and dependent medical and pharmacy claims. Asthma diagnosis or pharmacy claims for asthma controller medications were used to identify employees with dependents younger than 12 years for the asthma cohort. Controls were identified based on dependent age and lack of an asthma diagnosis or pharmacy claim for a controller medication. All costs were calculated using 2-part regression models that controlled for demographics, job information, Charlson Comorbidity Index, and region. Costs were calculated for employee health care, prescriptions, sick leave, short- and long-term disability, and workers' compensation and dependent health care and prescriptions. Costs were compared for employees with children aged 0 through 3 years, 4 through 7 years, 8 through 11 years, and younger than 12 years.

RESULTS

Data were available for 11,794 asthma cohort employees and 64,812 controls. Statistically significant annual cost differences were identified for employee health care ($154, P < .001), prescriptions ($95, P < .001), sick leave (-$41, P < .001), short-term disability (-$41, P = .008), dependent health care ($862, P < .001), and prescriptions ($534, P < .001).

CONCLUSIONS

Pediatric asthma is associated with significant additional health care and prescription costs for both employees and dependents.

Gout. Hyperuricemia and cardiovascular disease: how strong is the evidence for a causal link?

An association between high levels of serum urate and cardiovascular disease has been proposed for many decades. However, it was only recently that compelling basic science data, small clinical trials, and epidemiological studies have provided support to the idea of a true causal effect. In this review we present recently published data that study the association between hyperuricemia and selected cardiovascular diseases, with a final conclusion about the possibility of this association being causal.

Impact of noncompliance with urate-lowering drug on serum urate and gout-related healthcare costs: administrative claims analysis

OBJECTIVE

To determine the association between allopurinol compliance and serum urate (sUA) level; and examine the association between sUA and gout-related healthcare costs in a large managed care population.

RESEARCH DESIGN AND METHODS

This retrospective administrative claims analysis examined subjects with gout (> or = 2 medical claims with ICD-9-CM diagnosis code 274.xx or > or = 1 claim with a gout diagnosis and > or = 1 pharmacy claim for allopurinol, probenecid, colchicine, or sulfinpyrazone) between January 1, 2002 and March 31, 2004. Each subject was observed during 1-year pre-index and 1-year post-index periods.

MAIN OUTCOME MEASURES

Outcomes were allopurinol medication possession ratio (MPR) and compliance (MPR > or = 0.80), sUA (mg/dL), and gout-related healthcare costs. 'Post-allopurinol' sUA was measured during three periods after the first observed allopurinol fill: 30-89 days; 90-149 days; > or = 150 days. A baseline sUA on or before the start of the post-index period was also identified. Outcomes were stratified by post-allopurinol or baseline sUA and compliance. Generalized linear modeling (GLM) regression measured the impact of baseline sUA on gout-related healthcare costs, controlling for demographic and health status variables.

RESULTS

The study sample comprised 18,243 subjects with mean age of 53.9 years. In all, 55% (n = 10,073) of subjects used allopurinol. There were 1473 (8.1%) subjects with a post-allopurinol sUA and 2438 (13.4%) subjects with a baseline sUA result. Among all subjects with a post-allopurinol sUA, 45.6% were compliant; between 49.3% and 56.8% of compliant subjects had an sUA < 6.0 mg/dL compared with 22.5-27.8% of non-compliant subjects, depending on the post-allopurinol time period (all p < 0.001). GLM results showed gout-related costs associated with baseline sUA > or = 6.0 and < 9.0 mg/dL were 58% higher (95% confidence interval (CI): 1.012 -2.456; p = 0.044) than were costs for sUA < 6.0 mg/dL. There was no significant difference in gout-related costs between baseline sUA < 6.0 mg/dL and > or = 9.0 mg/dL.

CONCLUSIONS

Analysis revealed an important associations between allopurinol compliance, sUA, and gout-related costs: compliance was positively associated with favorable sUA (<6.0 mg/dL) in unadjusted comparisons. GLM showed that baseline sUA < 6.0 was inversely associated with gout-related costs relative to baseline sUA > or = 6.0 and <9.0 mg/dL. Nevertheless, a substantial portion of subjects, even compliant ones, did not achieve sUA < 6.0 mg/dL. These results should be interpreted carefully in light of study limitations, including incomplete laboratory data, the potentially incorrect inference that medications were taken as prescribed, and lack of generalizability from Medicare managed care enrollees to the broader Medicare population.

The impact of morbid obesity and bariatric surgery on comorbid conditions: a comprehensive examination of comorbidities in an employed population

OBJECTIVE

Find conditions with significantly different prevalence among employees diagnosed with morbid obesity (DMO). Examine the effect of bariatric surgery on the prevalence of all categories of comorbid conditions after surgery.

METHODS

This large employer retrospective database analysis used matching to create two cohorts: Those with a DMO and those without.

RESULTS

The DMO cohort had higher diagnosis rates in every Agency for Healthcare Research and Quality major diagnostic category except pregnancy, and it had significantly higher prevalence in 147 of 261 Agency for Health care Research and Quality specific categories. Those electing to undergo bariatric surgery experienced significant prevalence decreases in 26 of 261 specific categories.

CONCLUSION

Employees DMO are at higher risk for many serious diseases. Bariatric surgery has been effective in promoting weight loss and decreasing the rates of many serious comorbidities.