Incidence and prevalence of gout in Western Sweden

Temporal trends and regional disparity in rheumatoid arthritis and gout hospitalizations in Sweden, 1998-2015

Hospitalization is an important component of rheumatoid arthritis (RA) and gout economic burden. This study aimed to assess temporal trends and regional disparities in RA and gout hospitalizations among people aged ≥ 20 years in Sweden during 1998–2015. Data on hospital admissions with a principal diagnosis of RA or gout were collected from the National Patient Register. Age-standardized hospitalization rates (ASHRs) were calculated by means of direct standardization. The absolute and relative regional disparities were assessed. The temporal trends in ASHR and proportion of RA and gout hospitalizations from all and musculoskeletal disorders hospitalizations were analyzed using joinpoint regression. Between 1998–2000 and 2013–2015, the ASHR for RA declined by 78.9% from 109.9 to 23.2 per 100,000 Swedish adults, while it almost doubled for gout (from 10.5 to 20.8 per 100,000 Swedish adults). While in 1998–2000, RA hospitalizations were 10.3 times more frequent than gout (0.54 vs 0.05% of all hospitalizations), this ratio declined to 1.1 in 2013–2015 (0.13 vs 0.11% of all hospitalizations). The joinpoint regression revealed that, on average, the ASHR for RA declined by 10.2% (95% CI: 9.3–11.1) per year whereas for gout, it rose by 4.3% (3.2–5.4) per year during 1998–2015. While the relative regional disparities were stable, the absolute regional disparity declined for RA and increased for gout over the study period. While substantial decline in RA hospitalization is encouraging, the substantial rise in gout hospitalization is of concern, reflecting potential increase in prevalence of gout and suboptimal management of the disease.

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.

Effectiveness of an electronic patient-centred self-management tool for gout sufferers: a cluster randomised controlled trial protocol

INTRODUCTION

Gout is increasing despite effective therapies to lower serum urate concentrations to 0.36 mmol/L or less, which, if sustained, significantly reduces acute attacks of gout. Adherence to urate-lowering therapy (ULT) is poor, with rates of less than 50% 1 year after initiation of ULT. Attempts to increase adherence in gout patients have been disappointing. We aim to evaluate the effectiveness of use of a personal, self-management, 'smartphone' application (app) to achieve target serum urate concentrations in people with gout. We hypothesise that personalised feedback of serum urate concentrations will improve adherence to ULT.

METHODS AND ANALYSIS

Setting and designPrimary care. A prospective, cluster randomised (by general practitioner (GP) practices), controlled trial.

PARTICIPANTS

GP practices will be randomised to either intervention or control clusters with their patients allocated to the same cluster.

INTERVENTION

The intervention group will have access to the Healthy.me app tailored for the self-management of gout. The control group patients will have access to the same app modified to remove all functions except the Gout Attack Diary.

PRIMARY AND SECONDARY OUTCOMES

The proportion of patients whose serum urate concentrations are less than or equal to 0.36 mmol/L after 6 months. Secondary outcomes will be proportions of patients achieving target urate concentrations at 12 months, ULT adherence rates, serum urate concentrations at 6 and 12 months, rates of attacks of gout, quality of life estimations and process and economic evaluations. The study is designed to detect a ≥30% improvement in the intervention group above the expected 50% achievement of target serum urate at 6 months in the control group: power 0.80, significance level 0.05, assumed 'dropout' rate 20%.

ETHICS AND DISSEMINATION

This study has been approved by the University of New South Wales Human Research Ethics Committee. Study findings will be disseminated in international conferences and peer-reviewed journal.

TRIAL REGISTRATION NUMBER

ACTRN12616000455460.

Incidence of and risk factors for nephrolithiasis in patients with gout and the general population, a cohort study

BACKGROUND

Nephrolithiasis (NL) is known to be associated with gout, although there are few comparative studies on risk and risk factors for NL in gout compared to population cohorts. In this cohort study we investigated: (1) overall incidence of NL in gout (cases) and general population controls; (2) risk and risk factors (common comorbidities and medications) for first-time NL in cases and controls separately.

METHODS

Cases (n = 29,968) and age-matched and sex-matched controls (n = 138,678) were identified from the regional healthcare database in western Sweden (VEGA). The analyzed risk factors (comorbidities and current medication use) for first-time NL, and socioeconomic factors were retrieved from VEGA and other national Swedish registers. For cases, follow up began on 1 January 2006 or on the first diagnosis of gout if this occurred later, and for controls on their index patient's first diagnosis of gout. Follow up ended on death, emigration or 31 December 2012. Incidence rates (IR) per 1000 person-years and hazard ratios (HR) were calculated. The incidence calculations were performed for cases (regardless of prior NL) and their controls. HRs with first occurrence of NL as outcome were calculated only in those without previous NL.

RESULTS

In cases there were 678 NL events (IR: 6.16 events per 1000 person-years (95% CI: 5.70-6.64) and in controls 2125 NL events (IR 3.85 events per 1000 person-years (95% CI: 3.69-4.02), resulting in an age-sex-adjusted incidence rate ratio of 1.60 (95% CI:1.47-1.74). Point estimates for predictive factors were similar in cases and controls, except for a significant interaction for losartan which increased the risk of NL only in controls (HR = 1.49 (95% CI: 1.03-2.14). Loop diuretics significantly decreased the risk of NL by 30-34% in both cases and controls. Further significant predictors of NL in gout cases were male sex, diabetes and obesity and in controls male sex and kidney disease.

CONCLUSIONS

The risk (age and sex adjusted) of NL was increased by 60% in cases compared to controls. None of the commonly used medications increased the risk of NL in gout patients.

Prevalence and incidence of gout in Korea: data from the national health claims database 2007-2015

The purpose of the present study was to investigate the prevalence and incidence of gout in Korea and predict the future prevalence and incidence of gout. Data were collected from the national health claims database. Patients who had at least one claim for gout between 2007 and 2015 were included in the study. The prevalence of gout from 2007 to 2015 and the incidence of gout from 2009 to 2015 were determined. We estimated sex- and age-specific prevalence and incidence of gout during the period. The prevalence and incidence of gout were predicted using time series analysis. The prevalence of gout (95% CI) increased from 3.49 (3.48-3.51) per 1000 persons in 2007 to 7.58 (7.55-7.60) per 1000 persons in 2015. The incidence of gout (95% CI) was 1.52 (1.51-1.53) in 2009 and rose to 1.94 (1.93-1.95) per 1000 persons in 2015. The prevalence and incidence of gout were higher in men than in women. The older population had a higher prevalence and incidence than the younger population. The increase in prevalence was higher in the older population than the younger population, whereas the increase in incidence was higher in the younger population than the older population. The predicted prevalence and incidence of gout (95% CI) in 2025 were 16.59 (15.85-17.34) per 1000 persons and 3.81 (3.14-4.47) per 1000 persons. The prevalence and incidence of gout increased in Korea between 2007 and 2015. Men and the older population had a higher prevalence and incidence of gout compared to women and the younger population. However, the incidence of gout in the younger population has increased rapidly in recent years.

Factors associated with initiation and persistence of urate-lowering therapy

Background

Gout is the most common inflammatory arthritic disease and is caused by crystal deposition secondary to persistent hyperuricemia. Etiological treatment with urate-lowering therapy (ULT) has been available since the 1950s but previous studies have demonstrated suboptimal degree of treatment. In recent years we have seen recommendations for ULT earlier in the course of the disease, but there are few contemporary reports reflecting the current situation. Therefore we set out to investigate proportion receiving and persisting with ULT after gout diagnosis and predictors thereof.

Method

A population-based cohort study using regional and national population-based registers. Cohort of patients (n = 7709) from western Sweden with incident gout aged 18 years and above from 2011 to 2013. An incident case of gout was defined as having been given a diagnosis of gout (ICD-10 M10, M14.0-14.1) not preceded by a gout diagnosis or a dispensation of ULT during the previous 5 years. Main outcome measures were cumulative incidence and predictors for start of, and persistence with, ULT in gout.

Results

Within the first year after first gout diagnosis, 32% received ULT. Male sex, presence of diabetes or cardiovascular comorbidity, reduced kidney function but not diagnosed “end-stage kidney failure” increased the likelihood of receiving ULT. Of those starting ULT a majority (75%) did not persist with ULT treatment within the first 2 years. Age <50 years, lack of comorbidities, and “normal kidney function” or “end-stage kidney failure” were associated with non-persistence with ULT.

Conclusions

Only a minority of patients received ULT and a majority of these did not persist with treatment over the next 2 years. However, the older patients with renal impairment and comorbidities, possibly suffering from a more severe gout disease, were more likely to receive and persist with treatment. There is thus still room for considerable improvement with regards to management of ULT in gout.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-016-1211-y) contains supplementary material, which is available to authorized users.

Gout: will the "King of Diseases" be the first rheumatic disease to be cured?

Gout is the most common inflammatory arthritis in adults in the Western world. Characterized by hyperuricemia and the effects of acute and chronic inflammation in joints and bursa, gout leads to an agonizing, chronically painful arthritis. Arthritis can also be accompanied by urate nephropathy and subcutaneous urate deposits (tophi). Exciting new developments in the last decade have brought back the focus on this interesting, crystal-induced chronic inflammatory condition. New insights include the role of NALP3 inflammasome-induced inflammation in acute gout, the characterization of diagnostic signs on ultrasound and dual-energy computed tomography imaging modalities, the recognition of target serum urate less than 6 mg/day as the goal for urate-lowering therapies, and evidence-based treatment guidelines. A better understanding of disease mechanisms has enabled drug discovery - three new urate-lowering drugs have been approved in the last decade, with several more in the pipeline. We now recognize the important role that environment and genetics play in the causation of gout. A focus on the cardiac, renal, and metabolic comorbidities of gout will help translational research and discovery over the next decade.

Comorbidity of gout and rheumatoid arthritis in a large population database

Coexistence of rheumatoid arthritis and gout is considered to be unusual. The current study was designed as a population-based cross-sectional study, utilizing the medical database of Clalit Health Services, the largest healthcare provider organization in Israel. Data of adult patients who were previously diagnosed with rheumatoid arthritis was retrieved. For each patient, five age- and sex-matched control patients were randomly selected. Different parameters including BMI, socioeconomic status, and existence of gout as well as smoking and hypertension were examined for both groups. The study included 11,540 patients with rheumatoid arthritis and 56,763 controls. The proportion of gout in the study group was high compared to controls (1.61 vs. 0.92%, P < 0.001). In a multivariate analysis, rheumatoid arthritis was associated with gout (OR = 1.72, 95% CI 1.45-2.05, P = 0.00). The proportion of gout in rheumatoid arthritis patients is not lower than in the general population.

Prevalence and incidence of gout in southern Sweden from the socioeconomic perspective

OBJECTIVES

To estimate the prevalence and cumulative incidence of gout in southern Sweden with respect to socioeconomic status.

METHODS

Among residents of Skåne region in the year 2013 (total population 1.3 million), adult persons (age 18 years +) who between 1998 and 2013 received a diagnosis of gout (International Classification of Disease 10th Edition (ICD-10) code M10) by any physician were identified using the Skåne Healthcare Register. We calculated the point prevalence by end of 2013 and annual cumulative incidence in 2013 standardised to the whole Skåne population according to sex, individual information on occupation (white collar/blue collar), income (low/middle/high) and level of education (primary school/high school/university).

RESULTS

The crude 2013 point prevalence of gout and 2013 cumulative incidence (95% CI) were 1.69% (1.66% to 1.71%) and 24 cases per 10 000 persons (23-25), respectively. Compared to women, men had higher point prevalence (2.44% (2.40% to 2.49%) vs 0.96% (0.93% to 0.98%)) and higher annual cumulative incidence (33 cases per 10 000 (32-35)) versus 15 (14-16)). These figures increased with higher age but decreased with higher level of education, being the lowest in individuals with a university degree. Persons with middle income had highest point prevalence and cumulative incidence of gout, while those with white collar occupations had the lowest.

CONCLUSIONS

Gout is the most common inflammatory arthritis in southern Sweden with a prevalence of ∼1.7% in the adult population. There is a socioeconomic gradient with more gout present in the lower level of education and with more manual labour.

The rising prevalence and incidence of gout in British Columbia, Canada: Population-based trends from 2000 to 2012

OBJECTIVES

Gout is increasingly recognized as the most common form of inflammatory arthritis worldwide; however, no Canadian data on the disease burden of gout are available. We estimated the prevalence, incidence, prescription patterns, and comorbidity burden of gout in an entire Canadian province [British Columbia (BC)] over the last decade.

METHODS

We utilized PopulationData BC, a province-wide database, to estimate temporal trends in the prevalence and incidence of gout from 2000 to 2012, as well as according to age category. Annual estimates were age-sex-standardized using 2012 as the reference. We also examined annual trends in prescription patterns of common gout medications and assessed the comorbidity burden among gout patients in 2012.

RESULTS

The 2012 prevalence of gout was 3.8% among the overall population, and the incidence rate was 2.9 per 1000 person-years. Both gout prevalence and incidence increased substantially over the study period. This burden additionally increased according to age category, affecting over 8% of those ages 60-69 years in 2012. Approximately 22% of gout patients received a prescription for urate-lowering therapy (ULT), which remained stable over the study period, while colchicine and oral glucocorticoid use both increased modestly. By 2012, 72%, 52%, and 18% of prevalent gout patients had been diagnosed with hypertension, hyperlipidemia, and diabetes, respectively.

CONCLUSIONS

The burden of gout in BC, Canada, is substantial, and both the prevalence and incidence have increased over the past decade, while prescription of ULT remains low. These data support the need to improve gout prevention and care.