Gout, not induced by diuretics? A case-control study from primary care

Prescribing cascades of antigout medications from thiazide diuretics in gout-naïve hypertensive adults receiving first-line pharmacological management

Prescribing cascade is a significant clinical problem but is often overlooked. We explore the incidence of the prescribing cascades of antigout medications related to thiazide treatment in gout-naïve hypertensive adults newly exposed to the pharmacological treatment. This population-based, retrospective cohort study used the Taiwan National Health Insurance Registry Database. Gout-naïve hypertensive adults who were newly dispensed first-line antihypertensive drugs between January 1, 2000, and December 31, 2016, were enrolled. Patients were divided into the thiazide group (n = 4192) and the non-thiazide group (n = 81,083). The non-thiazide group included patients who received an angiotensin-converting enzyme inhibitor, angiotensin II receptor blocker, calcium channel blocker, or beta-blocker. The study utilized propensity score matching and multivariable Cox regression models to investigate the prescribing cascade of antigout agents following antihypertensive treatment, adjusting for factors like age, sex, comorbidities, and concurrent medications. After propensity score matching, each group consisted of 4045 patients, with the thiazide group exhibiting a higher risk of being prescribed antigout medications across different time intervals post-treatment initiation. Specifically, adjusted hazard ratios (aHRs) for the thiazide group were 2.23, 2.07, and 2.41 for < 30 days, 31-180 days, and > 180 days, respectively, indicating a sustained and significant risk over time. Comparative analyses revealed thiazide diuretics were associated with a higher risk of antigout medication prescriptions compared to other antihypertensive classes, particularly evident after 180 days. Subgroup analyses across various demographics and comorbidities consistently showed an increased risk in the thiazide cohort. Gout-naïve hypertensive adults newly dispensed thiazide had a higher risk of subsequently adding antigout agents than those taking other first-line antihypertensive medications. The awareness and interruption of these prescribing cascades are critical to improving patient safety.

Risk of gout in Taiwan Biobank participants pertaining to their sex and family history of gout among first-degree relatives

BACKGROUND

Family history of gout and sex are independently associated with gout. However, there is a paucity of research regarding the joint role of both factors in gout pathogenesis. Therefore, we assessed the independent and combined association of family history of gout and sex with gout.

METHODS

Our analysis included 132,311 Taiwan Biobank (TWB)-enrolled individuals comprising 21,159 gout cases and 111,152 controls. We subcategorized the family history of gout as (1) both siblings and parents had gout), (2) only parents had gout, and (3) only siblings had gout.

RESULTS

Generally, sex (men compared to women) and family history of gout were independently associated with a higher risk of gout. The odds ratio (OR); 95% confidence interval (CI) was 9.175; 8.801-9.566 for sex, and 2.306; 2.206-2.410 for family history. For the subcategories 'both siblings and had gout,' 'only parents had gout,' and 'only siblings had gout,' the odds ratios (ORs); 95% confidence intervals (CIs) were 4.944; 4.414-5.538, 2.041; 1.927-2.161, and 2.162; 2.012-2.323, respectively. The interaction between sex and family history was significant (p value = 0.0001). After stratification by sex, family history of gout remained significantly associated with a higher risk of gout in both sexes, even though the odds ratios were higher in men. For the subcategories 'both siblings and parents had gout,' 'only parent had gout,' and 'only siblings had gout,' the corresponding ORs; 95% CIs were 6.279; 5.243-7.520, 2.211; 2.062-2.371, and 2.148; 1.955-2.361 in men and 4.199; 3.566-4.945, 1.827; 1.640-2.035, and 2.093; 1.876-2.336 in women. After integrating sex and family history (reference: women with no family history), the highest risk of gout was observed in men who had at least one parent and sibling with a history of gout (OR; 95% CI 55.774; 46.360-67.101).

CONCLUSION

Sex and family history of gout were independently and interactively associated with gout. Sex-wise, men had a higher risk of gout than women. Family history was associated with a higher risk of gout in both sexes, but men had a higher risk. Notably, men having both siblings and parents with gout had the highest risk of gout.

Association of colchicine use for acute gout with clinical outcomes in acute decompensated heart failure

Background

Gout is a common comorbidity in heart failure (HF) patients and is frequently associated with acute exacerbations during treatment for decompensated HF. Although colchicine is often used to manage acute gout in HF patients, its impact on clinical outcomes when used during acute decompensated HF is unknown.

Methods

This was a single center, retrospective study of hospitalized patients treated for an acute HF exacerbation with and without acute gout flare between March 2011 and December 2020. We assessed clinical outcomes in patients treated with colchicine for a gout flare compared to those who did not experience a gout flare or receive colchicine. The primary outcome was in‐hospital all‐cause mortality.

Results

Among 1047 patient encounters for acute HF during the study period, there were 237 encounters (22.7%) where the patient also received colchicine for acute gout during admission. In‐hospital all‐cause mortality was significantly reduced in the colchicine group compared with the control group (2.1% vs. 6.5%, p = .009). The colchicine group had increased length of stay (9.93 vs. 7.96 days, p < .001) but no significant difference in 30‐day readmissions (21.5% vs. 19.5%, p = .495). In a Cox proportional hazards model adjusted for age, inpatient colchicine use was associated with improved survival to discharge (hazards ratio [HR] 0.163, 95% confidence interval [CI] 0.051−0.525, p = .002) and a reduced rate of in‐hospital CV mortality (HR 0.184, 95% CI 0.044−0.770, p = .021).

Conclusion

Among patients with a HF exacerbation, treatment with colchicine for a gout flare was associated with significantly lower in‐hospital mortality compared with those not treated for acute gout.

Do Serum Urate-associated Genetic Variants Influence Gout Risk in People Taking Diuretics? Analysis of the UK Biobank

OBJECTIVE

The aim of this study was to determine whether serum urate (SU)-associated genetic variants differ in their influence on gout risk in people taking a diuretic compared to those not taking a diuretic.

METHODS

This research was conducted using the UK Biobank Resource (n = 359,876). Ten SU-associated single-nucleotide polymorphisms (SNP) were tested for their association with gout according to diuretic use. Gene-diuretic interactions for gout association were tested using a genetic risk score (GRS) and individual SNP by logistic regression adjusting for relevant confounders.

RESULTS

After adjustment, use of a loop diuretic was positively associated with prevalent gout (OR 2.34, 95% CI 2.08-2.63), but thiazide diuretics were inversely associated with prevalent gout (OR 0.60, 95% CI 0.55-0.66). Compared with a lower GRS (< mean), a higher GRS (≥ mean) was positively associated with gout in those not taking diuretics (OR 2.63, 2.49-2.79), in those taking loop diuretics (OR 2.04, 95% CI 1.65-2.53), in those taking thiazide diuretics (OR 2.70, 2.26-3.23), and in those taking thiazide-like diuretics (OR 2.11, 95% CI 1.37-3.25). No nonadditive gene-diuretic interactions were observed.

CONCLUSION

In people taking diuretics, SU-associated genetic variants contribute strongly to gout risk, with a similar effect to that observed in those not taking a diuretic. These findings suggest that the contribution of genetic variants is not restricted to people with "primary" gout, and that genetic variants can play an important role in gout susceptibility in the presence of other risk factors.

Hyperuricemia Associated with Thiazide Diuretics in Hypertensive Adults

Introduction

Thiazide diuretics are essential first-line anti-hypertensive drugs which not only maintain blood pressure but also reduce stroke and congestive heart failure associated with morbidity and mortality in hypertensive patients. However, thiazide diuretics are associated with elevated serum uric acid (SUA) levels. This study aimed to evaluate the impact of thiazide diuretic use on their SUA levels among hypertensive individuals of Pakistan.

Methods

In this cross-sectional, prospective study, adult hypertensive patients were recruited. They were divided into two groups - thiazide diuretic group and non-thiazide group. Demographic characteristics, hypertension-related characteristics, and SUA levels were included. Data were then entered and analysed using SPSS for Windows version 22.0 (IBM Corp., Armonk, NY, USA).

Results

In the thiazide group, 24.5% were hyperuricemic as compared to 15.3% in the non-thiazide group (p=0.03). The overall mean SUA levels in the thiazide group were significantly higher than those in the non-thiazide group (5.9 ± 2.1 vs. 5.3 ± 2.7 mg/dL; p=0.02). Males in the thiazide group also showed a similar pattern (5.9 ± 2.3 vs. 5.1 ± 2.1 mg/dL; p=0.02); however, the differences were insignificant in females. Patients using thiazide diuretics for one to three years were more non-hyperuricemic than hyperuricemic (p=0.000). Among hyperuricemic patients, 36.5% were taking thiazides for three to four years and 46% were taking them for more than four years (p<0.05).

Conclusion

Hyperuricemia is a more common occurrence in thiazide diuretic users as compared to non-users. The overall sample, and men using thiazide diuretics, reported a higher mean SUA as compared to non-users. As the years of thiazide usage advanced, the number of hyperuricemic participants also significantly increased.

Impact of diuretics on the urate lowering therapy in patients with gout: analysis of an inception cohort

Background

Diuretics have been associated with impaired response and refractoriness in gout, but whether this effect is still present with new urate-lowering drugs (ULD) and treat-to-target strategies is unknown. The aim of the present study was to assess the impact of the diuretics on the response to ULD in patients with gout. 

Methods

This was a retrospective analysis of an inception cohort. Participants were classified according to the type of ULD prescribed. We analysed the maximal dose of ULD (primary outcome variable), serum urate (SU) reduction, and the achievement of different SU targets (6 mg/dL, 5 mg/dL, and 4 mg/dL), according to the type of ULD prescribed and use of diuretics (loop and/or thiazide). We adjusted for confounders using multiple linear regression analysis.

Results

We included 245 patients: 208 treated with allopurinol (66 on diuretics, 31.7%), 35 with febuxostat (19 on diuretics, 57.6%), and 2 with benzbromarone. Significantly fewer participants in the allopurinol plus diuretics subgroup achieved SU levels of less than 5 mg/dL, but we found no other significant differences in SU targets associated with diuretics. Regarding the maximum ULD dose, a simple linear regression suggested an inverse relationship with diuretics (beta = − 0.125, p = 0.073), but this did not hold in the multivariable analysis (beta = − 0.47, p = 0.833). There was no association with febuxostat (beta = − 0.116, p = 0.514).

Conclusion

Diuretics do not appear to have a significant impact on managing gout.

Electronic supplementary material

The online version of this article (10.1186/s13075-018-1559-2) contains supplementary material, which is available to authorized users.

Gout

Gout is a chronic disease of deposition of monosodium urate crystals, which form in the presence of increased urate concentrations. Although environmental factors contribute to hyperuricaemia, renal and gut excretion of urate is central to regulation of serum urate, and genetic factors are important. Activation of the NLRP3 inflammasome and release of interleukin 1β have key roles in initiation of acute gout flares. A "treat to target serum urate" approach is essential for effective gout management; long-term lowering of serum urate to less than 360 μmol/L leads to crystal dissolution and ultimately to suppression of flares. An allopurinol dose-escalation strategy is frequently effective for achieving treatment targets, and several new urate-lowering drugs are also available. Worldwide, rates of initiation and continuation of urate-lowering therapy are very low, and, consequently, achievement of serum urate targets is infrequent. Strategies to improve quality of gout care are needed.

Epidemiology and health-related services

PURPOSE OF REVIEW

This article presents recent epidemiologic contributions focusing on gout-related conditions, especially if controversial, to find plausible, despite hypothetical, mechanistic explanations from the clinician perspective.

RECENT FINDINGS

The prevalence of gout is increasing, but it is only partially clear that the incidence may be increasing as well. Direct associations of gout with increased risk of diabetes, black races, neurodegenerative disorders, and sugar-enriched foods have been recently questioned. A negative association with smoking has been reported, and new evidence shows that the impact of diet may be independent of obesity. Kidney disease and diuretics have been confirmed to be associated with gout, whereas new data on aging and menopause have come to challenge apparently established disease mechanisms. Regarding treatments, increase in bladder cancer associated with chronic allopurinol use has been reported, and the positive effect of urate-lowering treatment on cardiovascular events has been contested.

SUMMARY

Epidemiological data in gout-related conditions are still evolving and claim for future cohort or intervention studies to prove causality. Controversies in epidemiological results fertilize the ground for studies to prove mechanisms and causality and provides a unique opportunity for clinical intervention to improve outcomes, especially with regard to treatments.

A prospective evaluation of ultrasound as a diagnostic tool in acute microcrystalline arthritis

INTRODUCTION

The performance of ultrasound (US) in the diagnosis of acute gouty (MSU) arthritis and calcium pyrophosphate (CPP) arthritis is not yet well defined. Most studies evaluated US as the basis for diagnosing crystal arthritis in already diagnosed cases of gout and few prospective studies have been performed.

METHODS

One hundred nine consecutive patients who presented an acute arthritis of suspected microcrystalline arthritis were prospectively included. All underwent an US of the symptomatic joints(s) and of knees, ankles and 1(st) metatarsopalangeal (MTP) joints by a rheumatologist "blinded" to the clinical history. 92 also had standard X-rays. Crystal identification was the gold standard.

RESULTS

Fifty-one patients had MSU, 28 CPP and 9 had both crystals by microscopic analysis. No crystals were detected in 21. One had septic arthritis. Based on US signs in the symptomatic joint, the sensitivity of US for both gout and CPP was low (60% for both). In gout, the presence of US signs in the symptomatic joint was highly predictive of the diagnosis (PPV = 92%). When US diagnosis was based on an examination of multiple joints, the sensitivity for both gout and CPP rose significantly but the specificity and the PPV decreased. In the absence of US signs in all the joints studied, CPP arthritis was unlikely (NPV = 87%) particularly in patients with no previous crisis (NPV = 94%). X-ray of the symptomatic joints was confirmed to be not useful in diagnosing gout and was equally sensitive or specific as US in CPP arthritis.

CONCLUSIONS

Arthrocenthesis remains the key investigation for the diagnosis of microcrystalline acute arthritis. Although US can help in the diagnostic process, its diagnostic performance is only moderate. US should not be limited to the symptomatic joint. Examination of multiple joints gives a better diagnostic sensitivity but lower specificity.

Gout: A clinical overview and its association with cardiovascular diseases

Gout is a common disease caused by the deposition of monosodium urate (MSU) crystals in patients with hyperuricemia, and characterized by very painful recurrent acute attacks of arthritis. The gold standard for diagnosing gout is the identification of MSU crystals in synovial fluid by polarization light microscopy. Arthritis attacks can be treated with anti-inflammatory medications, such as non-steroidal anti-inflammatory drugs, colchicine, oral prednisone, or intra-articular or intramuscular glucocorticoids. To prevent gout uric acid lowering therapy with for example allopurinol can be prescribed. When gout is adequately treated, the prognosis is good. Unfortunately, the management of gout patients is often insufficient. Gout is associated with dietary factors, the use of diuretics, and several genetic factors. Comorbidities as hypertension, chronic kidney disease, cardiovascular diseases, the metabolic syndrome, diabetes, obesity, hyperlipidemia, and early menopause are associated with a higher prevalence of gout. Xanthine oxidase and chronic systemic inflammation seem to play an important role in the pathophysiology of the association between gout and cardiovascular diseases. To prevent cardiovascular diseases gout patients must be early screened for cardiovascular risk factors.

Use of diuretics and risk of incident gout: a population-based case-control study

OBJECTIVE

Use of diuretics has been associated with an increased risk of gout. Data on different types of diuretics are scarce. We undertook this study to investigate the association between use of loop diuretics, thiazide or thiazide-like diuretics, and potassium-sparing agents and the risk of developing incident gout.

METHODS

We conducted a retrospective population-based case-control analysis using the General Practice Research Database established in the UK. We identified case patients who were diagnosed as having incident gout between 1990 and 2010. One control patient was matched to each case patient for age, sex, general practice, calendar time, and years of active history in the database. We used conditional logistic regression to calculate odds ratios (ORs) and 95% confidence intervals (95% CIs), and we adjusted for potential confounders.

RESULTS

We identified 91,530 incident cases of gout and the same number of matched controls. Compared to past use of diuretics from each respective drug class, adjusted ORs for current use of loop diuretics, thiazide diuretics, thiazide-like diuretics, and potassium-sparing diuretics were 2.64 (95% CI 2.47-2.83), 1.70 (95% CI 1.62-1.79), 2.30 (95% CI 1.95-2.70), and 1.06 (95% CI 0.91-1.23), respectively. Combined use of loop diuretics and thiazide diuretics was associated with the highest relative risk estimates of gout (adjusted OR 4.65 [95% CI 3.51-6.16]). Current use of calcium channel blockers or losartan slightly attenuated the risk of gout in patients who took diuretics.

CONCLUSION

Use of loop diuretics, thiazide diuretics, and thiazide-like diuretics was associated with an increased risk of incident gout, although use of potassium-sparing agents was not.

Acute gouty arthritis complicated with acute ST elevation myocardial infarction is independently associated with short- and long-term adverse non-fatal cardiac events

Large epidemiologic studies have associated gouty arthritis with the risk of coronary heart disease. However, there has been a lack of information regarding the outcomes for patients who have gout attacks during hospitalization for acute myocardial infarction. We reviewed the data of 444 consecutive patients who were admitted to our hospital between 2005 and 2008 due to acute ST elevation myocardial infarction (STEMI). The clinical outcomes were compared between patients with gout attack and those without. Of the 444, 48 patients with acute STEMI developed acute gouty arthritis during hospitalization. The multivariate analysis identified prior history of gout and estimated glomerular filtration rate as independent risk factors of gout attack for patients with acute STEMI (odds ratio (OR) 21.02, 95 % CI 2.96-149.26, p = 0.002; OR 0.92, 95 % CI 0.86-0.99, p = 0.035, respectively). The in-hospital mortality and duration of hospital stay did not differ significantly between the gouty group and the non-gouty group (controls). During a mean follow-up of 49 ± 28 months, all-cause mortality and stroke were similar for both groups. Multivariate Cox regression showed that gout attack was independently associated with short- and long-term adverse non-fatal cardiac events (hazard ratio (HR) 1.88, 95 % CI 1.09-3.24, p = 0.024; HR 1.82, 95 % CI 1.09-3.03, p = 0.022, respectively). Gout attack among patients hospitalized due to acute STEMI was independently associated with short-term and long-term rates of adverse non-fatal cardiac events.

A case-control study of determinants for the occurrence of gouty arthritis in heart failure patients

AIMS

Gouty arthritis is a frequent and disabling complication in heart failure patients. This study aimed to investigate which factors are associated with the occurrence of gouty arthritis in these patients.

METHODS AND RESULTS

A case-control study was performed in heart failure patients (February 2007 to October 2009). Cases were defined as patients with gouty arthritis. Factors that are possibly associated with gouty arthritis and/or heart failure were evaluated. Echocardiographic dimensions and laboratory values including glomerular filtration rate (GFR) and fractional excretion of uric acid (FEUA) were measured. Logistic regression analysis was used to determine crude and adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for possibly associated factors. In total, 188 patients (59 with gouty arthritis) were included. Spironolactone use was associated with a decreased occurrence of gouty arthritis (OR 0.32, 95% CI 0.13-0.77). Independently associated with an increased occurrence of gouty arthritis were hypertensive heart failure (OR 3.6, 95% CI 1.6-8.2), New York Heart Association (NYHA) class III/IV (OR 4.5, 95% CI 1.8-11.0), lower GFR (P < 0.001), and FEUA <4% (OR 3.3, 95% CI 1.4-7.9). Among the four age/gender groups, the strongest association with gouty arthritis was found in men <65 years.

CONCLUSION

Our identification of factors that are associated with the occurrence of gouty arthritis makes it possible to develop strategies to improve further the quality of life in heart failure patients. The possible decreased occurrence of gouty arthritis in spironolactone users has to be confirmed in prospective studies.

Diuretic use, increased serum urate levels, and risk of incident gout in a population-based study of adults with hypertension: the Atherosclerosis Risk in Communities cohort study

OBJECTIVE

To quantify the role of diuretic use in gout development in an adult population with hypertension.

METHODS

The Atherosclerosis Risk in Communities study, a prospective population-based cohort from 4 US communities, consisted of 4 visits over a 9-year period. Participants were included in this analysis if they answered a query about gout, were free of gout at baseline, and had hypertension (defined as taking medication to treat hypertension or having blood pressure of ≥140/90 mm Hg). Trained interviewers recorded use of antihypertensive drugs. Incident gout was defined as self-reported onset of gout after baseline. Using a time-dependent Cox proportional hazards model, we estimated hazard ratios (HRs; with 95% confidence intervals [95% CIs]) for incident gout by time-varying diuretic use, both adjusted for confounders and tested for mediation by serum urate level.

RESULTS

There were 5,789 participants with hypertension; 37% were treated with a diuretic. Use of any diuretic (HR 1.48 [95% CI 1.11, 1.98]), a thiazide diuretic (HR 1.44 [95% CI 1.00, 2.10]), or a loop diuretic (HR 2.31 [95% CI 1.36, 3.91]) was associated with incident gout as compared with not using any diuretic, not using a thiazide diuretic, or not using a loop diuretic, respectively. After adjusting for serum urate level, the association between diuretic use and gout was null. Use of antihypertensive medication other than diuretic agents was associated with decreased gout risk (adjusted HR 0.64 [95% CI 0.49, 0.86]) compared to untreated hypertension. The longitudinal change in serum urate levels was 0.72 mg/dl (95% CI 0.57, 0.87) higher in those who began treatment with a diuretic than in those who did not (P<0.001).

CONCLUSION

Thiazide and loop diuretics were associated with increased gout risk, an association mediated by a change in serum urate levels.

Use of diuretics and the risk of gouty arthritis: a systematic review

OBJECTIVE

To systematically review the literature investigating the relationship between use of diuretics and the risk of gouty arthritis.

METHODS

PubMed (1950-October 2009), Embase (1974-October 2009), and the Cochrane Library (up to October 2009) were searched using keywords and MeSH terms diuretics, adverse effects, and gout. For this review, the technique of "best evidence synthesis" was used. Studies reporting frequency, absolute or relative risks, odds ratio, or rate ratio of gouty arthritis in diuretic users compared with nonusers were selected and evaluated. Studies had to be published in English. Checklists from the Dutch Cochrane Centre were used to assess the quality of randomized controlled trials (RCTs), cohort, and case-control studies.

RESULTS

Two RCTs, 6 cohort studies, and 5 case-control studies met the inclusion criteria. The overall quality of the studies was moderate. In a RCT the rate ratio of gout for use of bendrofluazide vs placebo was 11.8 (95% CI 5.2-27.0). The other RCT found a rate ratio of 6.3 (95% CI 0.8-51) for use of hydrochlorothiazide plus triamterene vs placebo. Three cohort studies and 4 case-control studies found higher risks of gouty arthritis in users compared with nonusers of diuretics.

CONCLUSIONS

There is a trend toward a higher risk for acute gouty arthritis attacks in patients on loop and thiazide diuretics, but the magnitude and independence is not consistent. Therefore, stopping these useful drugs in patients who develop gouty arthritis is not supported by the results of this review.

The independent impact of congestive heart failure status and diuretic use on serum uric acid among men with a high cardiovascular risk profile: a prospective longitudinal study

OBJECTIVE

To evaluate the independent impact of congestive heart failure (CHF) status (compensation or decompensation) on serum uric acid levels among men with high cardiovascular risk profile.

METHOD

We analyzed 11,681 men from the Multiple Risk Factor Interventional Trial, using data prospectively collected at baseline and annually over 6 years (64,644 visits). We evaluated the impact of change in CHF status during study follow-up, as compared with study baseline, on hyperuricemia (serum uric acid ≥7 mg/dL) and serum uric acid levels, using generalized estimating equations, adjusting for age, race, weight, weight change, education, alcohol intake, diuretic use, hypertension, serum creatinine level, and dietary factors. Similarly, we evaluated the independent impact of change in diuretic use (initiation or discontinuation).

RESULTS

At baseline, mean serum uric acid was 6.88 mg/dL. Compared with no change in CHF status, odds ratios of hyperuricemia were 1.67 (95% CI, 1.21 to 2.32) for CHF decompensation and 0.21 (95% CI, 0.08 to 0.55) for compensation. The corresponding uric acid differences were 0.41 (95% CI, 0.20 to 0.62) and -1.00 (95% CI, -1.72 to -0.27), respectively. The odds ratios for initiation and discontinuation of diuretic were 3.32 (95% CI, 3.06 to 3.61) and 0.39 (95% CI, 0.35 to 0.44).

CONCLUSIONS

CHF decompensation and diuretic use are both independently associated with increased odds of hyperuricemia among men with a high cardiovascular risk profile, whereas CHF recovery and diuretic discontinuation are associated with substantially lower odds of hyperuricemia.

Contemporary epidemiology of gout in the UK general population

Introduction

The objective of this study was to investigate the contemporary incidence of gout, examine potential risk factors, and evaluate specific gout treatment patterns in the general population.

Methods

Using the health improvement network (THIN) UK primary care database, we estimated the incidence of gout based on 24,768 newly diagnosed gout patients among a cohort of 1,775,505 individuals aged 20 to 89 years between 2000 and 2007. We evaluated potential risk factors for incident gout in a nested case-control study with 50,000 controls frequency-matched by age, sex and calendar time. We calculated odds ratios (OR) by means of unconditional logistic regression adjusting for demographic variables, lifestyle variables, relevant medical conditions and drug exposures.

Results

The incidence of gout per 1,000 person-years was 2.68 (4.42 in men and 1.32 in women) and increased with age. Conventional risk factors were significantly and strongly associated with the risk of gout, with multivariate ORs of 3.00 (95% confidence interval (CI)) for excessive alcohol intake (that is, more than 42 units per week), 2.34 (95% CI 2.22 to 2.47) for obesity (body mass index > = 30 kg/m²), 2.48 (95% CI 2.19 to 2.81) for chronic renal impairment, and 3.00 (95% CI 2.85 to 3.15) for current diuretic use. For other medical conditions the multivariate OR were 1.84 (95% CI 1.70 to 2.00) for heart failure, 1.45 (95% CI 1.18 to 1.79) for hypertriglyceridemia and 1.12 (95% CI 1.04 to 1.22) for psoriasis. Use of cyclosporine was associated with an OR of 3.72 (95% CI, 2.17 to 6.40). Among gout-specific therapies, allopurinol was the most frequently used with a one-year cumulative incidence of 28% in a cohort of incident gout diagnosed from 2000 to 2001. Use of gout-specific treatment has not changed over recent years except for an increase of colchicine.

Conclusions

The contemporary incidence of gout in UK remains substantial. In this general population cohort, associations with previously purported risk factors were evident including psoriasis, heart failure, hypertriglyceridemia, and cyclosporine therapy. Use of gout-specific treatment has remained relatively constant in recent years except for an increase of colchicine.

Risk factors for gout and prevention: a systematic review of the literature

PURPOSE OF REVIEW

Our objective was to perform a systematic review of risk factors and prevention of gout. We searched Medline for fully published reports in English using keywords including but not limited to 'gout', 'epidemiology', 'primary prevention', 'secondary prevention', 'risk factors'. Data from relevant articles meeting inclusion criteria were extracted using standardized forms.

RECENT FINDINGS

Of the 751 titles and abstracts, 53 studies met the criteria and were included in the review. Several risk factors were studied. Alcohol consumption increased the risk of incident gout, especially beer and hard liquor. Several dietary factors increased the risk of incident gout, including meat intake, seafood intake, sugar sweetened soft drinks, and consumption of foods high in fructose. Diary intake, folate intake, and coffee consumption were each associated with a lower risk of incident gout and in some cases a lower rate of gout flares. Thiazide and loop diuretics were associated with higher risk of incident gout and higher rate of gout flares. Hypertension, renal insufficiency, hypertriglyceridemia, hypercholesterolemia, hyperuricemia, diabetes, obesity, and early menopause were each associated with a higher risk of incident gout and/or gout flares.

SUMMARY

Several dietary risk factors for incident gout and gout flares are modifiable. Prevention and optimal management of comorbidities are likely to decreased risk of gout. Research in preventive strategies for the treatment of gout is needed.

Lack of effect of hydrochlorothiazide and low-dose aspirin on the renal clearance of urate and oxypurinol after a single dose of allopurinol in normal volunteers

AIMS

To determine whether low-dose aspirin and hydrochlorothiazide (HCTZ) affect the renal clearance of oxypurinol and/or urate.

METHODS

Healthy volunteers (n = 8) were treated with allopurinol (600 mg, control), and allopurinol (600 mg) co-administered with single doses of aspirin (100 mg) or HCTZ (25 mg) or a combination of the two.

RESULTS

Hydrochlorothiazide, low-dose aspirin or a combination of the two, when co-administered with allopurinol, did not significantly alter (P > 0.05) the renal clearance of oxypurinol or urate. In particular, aspirin and HCTZ, when taken together and with allopurinol, did not change (P > 0.05) oxypurinol fractional renal clearance (allopurinol alone: 0.217, 0.173-0.262; combined: 0.202, 0.155-0.250) or urate fractional renal clearance (allopurinol alone: 0.066, 0.032-0.099; combined: 0.058, 0.038-0.078).

CONCLUSIONS

A single, low-dose of aspirin or an anti-hypertensive dose of hydrochlorothiazide, when administered alone or together with allopurinol, are unlikely to alter the hypouricaemic effect of allopurinol. The effect of chronic aspirin and HCTZ dosing taken together upon the efficacy of chronic allopurinol therapy in patients with hyperuricaemia needs to be investigated.

Epidemiology of gout

Gout is the most prevalent form of inflammatory arthropathy. Several studies suggest that its prevalence and incidence have risen in recent decades. Numerous risk factors for the development of gout have been established, including hyperuricaemia, genetic factors, dietary factors, alcohol consumption, metabolic syndrome, hypertension, obesity, diuretic use and chronic renal disease. Osteoarthritis predisposes to local crystal deposition. Gout appears to be an independent risk factor for all-cause mortality and cardiovascular mortality and morbidity, additional to the risk conferred by its association with traditional cardiovascular risk factors.

New insights into the epidemiology of gout

Gout is a true crystal deposition disease caused by formation of monosodium urate crystals in joints and other tissues. It is a common inflammatory arthritis that has increased in prevalence in recent decades. Gout normally results from the interaction of genetic, constitutional and environmental risk factors. It is more common in men and strongly age related. A major determinant is the degree of elevation of uric acid levels above the saturation point for urate crystal formation, principally caused by inefficient renal urate excretion. Local joint tissue factors may influence the topography and extent of crystal deposition. Recent studies have provided information on dietary risk factors for gout: higher intakes of red meat, fructose and beer are independently associated with increased risk, whereas higher intakes of coffee, low-fat dairy products and vitamin C are associated with lower risk. Several renal urate transporters have been identified including URAT1 and SLC2A9 (GLUT9) and polymorphisms in these genes are associated with an increased risk of hyperuricaemia and gout. Many drugs influence serum uric acid levels through an effect on renal urate transport. Comorbidities, including the metabolic syndrome and impaired renal function are common in gout patients. The usual initial presentation of gout is with rapidly developing acute inflammatory monoarthritis, typically affecting the first MTP joint. If left untreated it may progress with recurrent acute attacks and eventual development of chronic symptoms and joint damage. New knowledge of the modifiable risk factors for gout can be integrated into the management strategy to optimize long-term patient outcomes.

Gout

Gout is a common arthritis caused by deposition of monosodium urate crystals within joints after chronic hyperuricaemia. It affects 1-2% of adults in developed countries, where it is the most common inflammatory arthritis in men. Epidemiological data are consistent with a rise in prevalence of gout. Diet and genetic polymorphisms of renal transporters of urate seem to be the main causal factors of primary gout. Gout and hyperuricaemia are associated with hypertension, diabetes mellitus, metabolic syndrome, and renal and cardiovascular diseases. Non-steroidal anti-inflammatory drugs and colchicine remain the most widely recommended drugs to treat acute attacks. Oral corticosteroids could be an alternative to these drugs. Interleukin 1beta is a pivotal mediator of acute gout and could become a therapeutic target. When serum uric acid concentrations are lowered below monosodium urate saturation point, the crystals dissolve and gout can be cured. Patient education, appropriate lifestyle advice, and treatment of comorbidities are an important part of management of patients with gout.

"Clinical features of women with gout arthritis." A systematic review

Clinically, gout is generally considered as a preferential male disease. However, it definitely does not occur exclusively in males. Our aim was to assess differences in the clinical features of gout arthritis between female and male patients. Five electronic databases were searched to identify relevant original studies published between 1977 and 2007. The included studies had to focus on adult patients with primary gout arthritis and on sex differences in clinical features. Two reviewers independently assessed eligibility and quality of the studies. Out of 355 articles, 14 were selected. Nine fulfilled the quality and score criteria. We identified the following sex differences in the clinical features of gout in women compared to men: the onset of gout occurs at a higher age, more comorbidity with hypertension or renal insufficiency, more often use of diuretics, less likely to drink alcohol, less often podagra but more often involvement of other joints, less frequent recurrent attacks. We found interesting sex differences regarding the clinical features of patients with gout arthritis. To diagnose gout in women, knowledge of these differences is essential, and more research is needed to understand and explain the differences , especially in the general population.

Use of oral prednisolone or naproxen for the treatment of gout arthritis: a double-blind, randomised equivalence trial

BACKGROUND

Non-steroidal anti-inflammatory drugs and colchicine used to treat gout arthritis have gastrointestinal, renal, and cardiovascular adverse effects. Systemic corticosteroids might be a beneficial alternative. We investigated equivalence of naproxen and prednisolone in primary care.

METHODS

We did a randomised clinical trial to test equivalence of prednisolone and naproxen for the treatment of monoarticular gout. Primary-care patients with gout confirmed by presence of monosodium urate crystals were eligible. 120 patients were randomly assigned with computer-generated randomisation to receive either prednisolone (35 mg once a day; n=60) or naproxen (500 mg twice a day; n=60), for 5 days. Treatment was masked for both patients and physicians. The primary outcome was pain measured on a 100 mm visual analogue scale and the a priori margin for equivalence set at 10%. Analyses were done per protocol and by intention to treat. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN14648181.

FINDINGS

Data were incomplete for one patient in each treatment group, so per-protocol analyses included 59 patients in each group. After 90 h the reduction in the pain score was 44.7 mm and 46.0 mm for prednisolone and naproxen, respectively (difference 1.3 mm; 95% CI -9.8 to 7.1), suggesting equivalence. The difference in the size of change in pain was 1.57 mm (95% CI -8.65 to 11.78). Adverse effects were similar between groups, minor, and resolved by 3 week follow-up.

INTERPRETATION

Oral prednisolone and naproxen are equally effective in the initial treatment of gout arthritis over 4 days.

Systemic corticosteroids for acute gout

BACKGROUND

Gout is one of the most frequently occurring rheumatic diseases, worldwide. Given the well-known drawbacks of the regular treatments for acute gout (non-steroidal anti-inflammatory drugs (NSAIDs), colchicine), systemic corticosteroids might be safe alternatives.

OBJECTIVES

To assess the efficacy and safety of systemic corticosteroids in the treatment of acute gout in comparison with placebo, NSAIDs, colchicine, other active drugs, other therapies, or no therapy.

SEARCH STRATEGY

Searches were done in the following electronic databases: Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2007); MEDLINE (1966 to 2007) through PubMed; EMBASE (1974 to 2007); Web of Science (1975 to 2007); LILACS (1986 to 2007); and databases of ongoing trials (up to April 2007).

SELECTION CRITERIA

Randomized controlled trials and controlled clinical trials investigating the use of systemic corticosteroids in the treatment of acute gout were included.

DATA COLLECTION AND ANALYSIS

Two review authors decided independently which trials to include. The same review authors also collected the data in a standardised form and assessed the methodological quality of the trial using validated criteria. When possible, continuous and dichotomous data were summarised statistically.

MAIN RESULTS

Three head to head trials involving 148 patients (74 systemic corticosteroids; 74 comparator drugs) were included. Placebo-controlled trials were not found. In the studies, different kinds of systemic corticosteroids and different kinds of control drugs were used, both administered in different routes. Intramuscular triamcinolone acetonide was compared respectively to oral indomethacine, and intramuscular adrenocorticotropic hormone (ACTH); oral prednisolone (together with a single intramuscular diclophenac injection) was compared to oral indomethacine (together with a single placebo injection). Outcome measurements varied: average number of days until total relief of signs, mean decrease of pain per unit of time in mm on a visual analogue scale (VAS) - during rest and activity. In the triamcinolone-indomethacine trial the clinical joint status was used as an additional outcome. Clinically relevant differences between the studied systemic corticosteroids and the comparator drugs were not found; important safety problems attributable to the used corticosteroids were not reported. The quality of the three studies was graded as very low to moderate. Statistical pooling of results was not possible.

AUTHORS' CONCLUSIONS

There is inconclusive evidence for the efficacy and effectiveness of systemic corticosteroids in the treatment of acute gout. Patients with gout did not report serious adverse effects from systemic corticosteroids, when used short term.

A composite screening tool for medication reviews of outpatients: general issues with specific examples

Regular performance of medication reviews is prominent among methods that have been advocated to reduce the extent and seriousness of drug-related problems, such as adverse drug reactions, drug-disease interactions, drug-drug interactions, drug ineffectiveness and cost ineffectiveness. Several screening tools have been developed to guide practising healthcare professionals and researchers in reviewing the medication patterns of elderly patients; however, each of these tools has its own limitations. This review discusses a wide range of general prescription-, treatment- and patient-related issues that should be taken into account when reviewing medication patterns by implicit screening. These include generic and therapeutic substitution; potentially superfluous or inappropriate medications; potentially inappropriate dosages or duration of treatment; drug-disease and drug-drug interactions; under-treatment; making use of laboratory test results; patient adherence, experiences and habits; appropriate dosage forms and packaging. A broad selection of specific examples and references that can be used as a basis for explicit screening of medication patterns in outpatients is also offered.

Gout in the UK and Germany: prevalence, comorbidities and management in general practice 2000-2005

Objective:

To investigate and compare the prevalence, comorbidities and management of gout in practice in the UK and Germany.

Methods:

A retrospective analysis of patients with gout, identified through the records of 2.5 million patients in UK general practices and 2.4 million patients attending GPs or internists in Germany, using the IMS Disease Analyzer.

Results:

The prevalence of gout was 1.4% in the UK and Germany. Obesity was the most common comorbidity in the UK (27.7%), but in Germany the most common comorbidity was diabetes (25.9%). The prevalence of comorbidities tended to increase with serum uric acid (sUA) levels. There was a positive correlation between sUA level and the frequency of gout flares. Compared with those in whom sUA was <360 μmol/l (<6 mg/dl), odds ratios for a gout flare were 1.33 and 1.37 at sUA 360–420 μmol/l (6–7 mg/dl), and 2.15 and 2.48 at sUA >530 μmol/l ( >9 mg/dl) in the UK and Germany, respectively (p<0.01).

Conclusions:

The prevalence of gout in practice in the UK and Germany in the years 2000–5 was 1.4%, consistent with previous UK data for 1990–9. Chronic comorbidities were common among patients with gout and included conditions associated with an increased risk for cardiovascular disease, such as obesity, diabetes and hypertension. The importance of regular monitoring of sUA in order to tailor gout treatment was highlighted by data from this study showing that patients with sUA levels ⩾360 μmol/l (⩾6 mg/dl) had an increased risk of gout flares.

Elderly-onset gout: a review

Elderly-onset gout (EOG), defined as a disease with onset at age 65 years or over, shows relevant epidemiological, clinical and therapeutic differences from the typical middle-age form. The main differences are the more frequent subacute/chronic polyarticular onset with hand involvement, the unusual localization of tophi on ostheoarthritis (OA) nodes, the increased female/male ratio and the frequent association with drugs that decrease renal urate excretion (diuretics and low-dose aspirin) and/or with primitive renal impairment. EOG has recently been confirmed as the most common inflammatory arthropathy in older people, with important demographic implications and substantial impact on daily clinical practice. Despite the high prevalence, gout, in the elderly, often remains misdiagnosed or diagnosed late in its clinical course. Even when correctly recognized, its treatment is often difficult or unsatisfactory.

Therapeutic advances in gout

PURPOSE OF REVIEW

The purpose of this review is to highlight the recent developments in the management of gout.

RECENT FINDINGS

Guidelines for the diagnosis and management of gout from EULAR, quality of care indicators, and outcome measures for clinical trials have been published. The standards of gout diagnosis and management are very low. Allopurinol remains the mainstay for serum uric acid lowering therapy. In an important percentage of patients receiving allopurinol, serum uric acid levels are insufficient to promote crystal dissolution. Febuxostat, a new serum uric acid lowering drug, has shown good results. Information on uricase continues to appear. For treatment of gouty inflammation, etoricoxib (a new cyclooxygenase 2 inhibitor) has been shown to be as effective as indomethacin. Finally, the association of gout with the metabolic syndrome and its comorbidities, and the newly described association of gout with myocardial infarction, bring lifestyle and dietary modifications to the front in the management of gout.

SUMMARY

Proper gout management requires changes to the physician's attitude towards the disease; essentially: (1) an unequivocal diagnosis based in urate crystal identification, (2) a clearly settled aim of the treatment: crystal elimination from the joints and elsewhere, and (3) proper use of the available therapeutic alternatives. Promoting a proper lifestyle appears to be especially important.

Crystal-Associated Arthritis in the Elderly

Since the original recognition of these conditions in 1961, a great deal has been learned about the pathogenesis, clinical manifestations, and appropriate treatment of gout and pseudogout, and the role of crystals in osteoarthritis has been further defined. The variable manifestations of crystal-induced arthritis in elderly populations has led to a greater need for proper diagnosis and treatment strategies for these increasingly common forms of arthritis.