Effect of bariatric surgery on the inflammatory response to monosodium urate crystals: a prospective study

Benefits of uric acid-lowering medication after bariatric surgery in patients with gout

BACKGROUND/PURPOSE

Patients with gout are at risk for increased serum uric acid (SUA) levels and gout attacks in the short term after undergoing bariatric surgery, and the purpose of this study was to evaluate the benefits of short-term treatment with uric acid-lowering medication after bariatric surgery for the control of gout attacks and SUA levels in patients with gout.

METHODS

71 patients who underwent SG from January 2020 to December 2022 were prospectively included. These patients were diagnosed with hyperuricemia before surgery and had a history of gout attacks. Patients were classified into a drug-treatment group (DTG, n = 32) and a non-drug-treatment group (NDTG, n = 39) according to whether they took uric acid-lowering medication after surgery. Changes in the number of gout attacks, body mass index (BMI), and SUA levels at 1 week, 1 month, 3 months, and 6 months after bariatric surgery were measured in both groups.

RESULTS

In the DTG, 22 patients (68.8%) experienced an increase in SUA within 1 week, 3 patients (9.4%) had an acute attack of gout within the first month, and no patients had a gout attack thereafter. In the NDTG, 35 patients (89.7%) experienced an increase in SUA within 1 week, 7 patients (17.9%) had an acute gout attack within the first month, and 4 patients (10.3%) experienced gout attacks between month 1 and month 3 postoperatively. Both groups were free of gout attacks between the 3rd and 6th postoperative month and showed a significant decrease in SUA and BMI by the sixth month.

CONCLUSION

In patients with gout, continued use of uric acid-lowering medication after bariatric surgery is beneficial in reducing the number of gout attacks and the risk of rising SUA.

Gouty arthritis and kidney function outcomes and serum uric acid level variations in obese patients following bariatric surgery

Background

Obesity is an independent risk factor for chronic kidney disease (CKD) and is the strongest known modifiable risk factor for hyperuricemia and gout. We aimed to discover the outcome of serum uric acid (SUA), gouty arthritis, and kidney function in obese patients after bariatric surgery and possible links with BMI variations.

Methods

Retrospective study has been performed in National Hospital in Riyadh, KSA, between Jan. 2018 to Jan. 2020. We studied only 98 patients who met our inclusion criteria. Patients followed-up at 1 month (for gouty attack only) postoperative, 3 months postoperative, and 6 months postoperative for body mass index (BMI), serum creatinine, dipstick urinalysis, SUA, and estimated glomerular filtration rate (eGFR). Radiological studies, medical history, follow up radiological studies, and clinical follow up were obtained from the hospital data system.

Results

A total of 98 patients with mean eGFR were 90.65 ± 29.34 ml/min/1.73 m2, mean SUA 5.56 ± 1.84 mg/dl, and mean BMI was 45.28 ± 7.25 kg/m2, at surgery. Mean BMI had decreased significantly to 38.52 ± 6.05 kg/m2 at 3 months and to 34.61 ± 5.35 kg/m2 at 6 months (P < 0.001). The mean GFR had improved significantly (99.14 ± 23.32 ml/min/1.73 m2) at 6 months (P < 0.001). Interestingly, proteinuria had resolved in 17 patients out of 23 patients at 6 months. Number of gouty attacks was decreased during the first month post-surgery (P < 0.001). SUA level was significantly decreased (4.32 ± 1.27 mg/dl) (P < 0.001). SUA showed significant negative correlations with eGFR at 3 months and positively significant correlations with BMI at 3 and 6 months. By multinomial logistic regression, BMI and initial eGFR were the independent predictive variables for the outcome of eGFR at 6 months, while male gender and initial SUA were the independent predictive variables on the outcome of SUA at 6 months. Postoperatively in gouty arthritis patients, the number of joints affected, patient global VAS assessment, and number of gouty attacks were significantly reduced (P < 0.001).

Conclusion

Bariatric surgery has been associated with reduction of BMI and subsequently reduction of SUA levels, gouty attacks, and improvement of eGFR.

Risk of gout among Taiwanese adults with ALDH-2 rs671 polymorphism according to BMI and alcohol intake

BACKGROUND

Gout stems from both modifiable and genetic sources. We evaluated the risk of gout among Taiwanese adults with aldehyde dehydrogenase-2 (ALDH2) rs671 single nucleotide polymorphism (SNP) according to body mass index (BMI) and alcohol drinking.

METHODS

We obtained information of 9253 individuals having no personal history of cancer from the Taiwan Biobank (2008-2016) and estimated the association between gout and independent variables (e.g., rs671, BMI, and alcohol drinking) using multiple logistic regression.

RESULTS

Alcohol drinking and abnormal BMI were associated with a higher risk of gout whereas the rs671 GA+AA genotype was associated with a lower risk. The odds ratios (ORs) and 95% confidence intervals (CIs) were 1.297 and 1.098-1.532 for alcohol drinking, 1.550 and 1.368-1.755 for abnormal BMI, and 0.887 and 0.800-0.984 for GA+AA. The interaction between BMI and alcohol on gout was significant for GG (p-value = 0.0102) and GA+AA (p-value = 0.0175). When we stratified genotypes by BMI, alcohol drinking was significantly associated with gout only among individuals with a normal BMI (OR; 95% CI = 1.533; 1.036-2.269 for GG and 2.109; 1.202-3.699 for GA+AA). Concerning the combination of BMI and alcohol drinking among participants stratified by genotypes (reference, GG genotype, normal BMI, and no alcohol drinking), the risk of gout was significantly higher in the following categories: GG, normal BMI, and alcohol drinking (OR, 95% CI = 1.929, 1.385-2.688); GG, abnormal BMI, and no alcohol drinking (OR, 95% CI, = 1.721, 1.442-2.052); GG, abnormal BMI, and alcohol drinking (OR, 95% CI = 1.941, 1.501-2.511); GA+AA, normal BMI, and alcohol drinking (OR, 95% CI = 1.971, 1.167-3.327); GA+AA, abnormal BMI, and no alcohol drinking (OR, 95% CI = 1.498, 1.256-1.586); and GA+AA, abnormal BMI, and alcohol drinking (OR, 95% CI = 1.545, 1.088-2.194).

CONCLUSIONS

Alcohol and abnormal BMI were associated with a higher risk of gout, whereas the rs671 GA+AA genotype was associated with a lower risk. Noteworthy, BMI and alcohol had a significant interaction on gout risk. Stratified analyses revealed that alcohol drinking especially among normal-weight individuals might elevate the risk of gout irrespective of the genotype.

Impact of psoriasis disease activity and other risk factors on serum urate levels in patients with psoriasis and psoriatic arthritis-a post-hoc analysis of pooled data from three phase 3 trials with secukinumab

Objectives

Our aims were to determine if the Psoriasis Area Severity Index (PASI) score and serum urate (SU) levels were associated at baseline and whether the change in PASI score during 12 weeks of treatment resulted in a significant change in SU, adjusted for relevant confounders.

Methods

Data from patients with psoriasis/PsA (n = 1042/204) in three phase 3 randomized control trials treated with secukinumab (dose 300 mg, n = 628) or placebo (n = 414) were pooled. At baseline, values for SU, PASI and the following covariates were assessed: age, sex, BMI, estimated glomerular filtration rate, and medication with diuretics. To assess the changes in PASI (ΔPASI) and SU (Δurate), the differences (week 12 minus baseline) in patients receiving the active drug were used. Multivariable linear regression, adjusting for covariates, was used to assess the association between PASI and SU at baseline with all patients pooled and to assess the association between Δurate and ΔPASI over 12 weeks of treatment with secukinumab.

Results

The degree of skin involvement of psoriasis showed a statistically significant, albeit modest, association with SU (R² = 0.014, P < 0.0001 univariately), whereas known risk factors for hyperuricaemia had a much larger impact cross-sectionally at baseline (R² = 0.33, P < 0.0001). Furthermore, a substantial improvement in PASI score resulted in only a modest decrease of SU over 12 weeks of treatment with secukinumab (R² = 0.014, P < 0.0001 univariately).

Conclusions

There is a statistically significant, albeit modest, association with both extent and change in PASI score and SU in patients with psoriasis, compatible with a potential pathophysiological relationship between urate and psoriasis.

Trial Registration

ERASURE: clinicaltrials.gov, https://clinicaltrials.gov, NCT01365455; FIXTURE: clinicaltrials.gov, https://clinicaltrials.gov, NCT01358578; SCULPTURE: clinicaltrials.gov, https://clinicaltrials.gov, NCT01406938

Do Serum Urate-Associated Genetic Variants Differentially Contribute to Gout Risk According to Body Mass Index? Analysis of the UK Biobank

OBJECTIVE

To examine whether urate-associated genetic variants differ in their influence on gout risk according to body mass index (BMI).

METHODS

This research was conducted using the UK Biobank Resource (n = 358,728). Participants were divided into 3 groups: BMI <25 kg/m² (low/normal), BMI ≥25 kg/m² -<30 kg/m² (overweight), and BMI ≥30 kg/m² (obese). Gene-BMI interactions for gout association were tested by logistic regression using a urate genetic risk score (GRS).

RESULTS

Compared to participants with a GRS less than the mean, the prevalence of gout was higher in those with a GRS greater than or equal to the mean in the low/normal BMI group (0.27% versus 0.77%), in the overweight BMI group (1.02% versus 3.02%), and in the obese BMI group (2.49% versus 6.23%). A GRS greater than or equal to the mean was positively associated with gout compared to a GRS less than the mean in the low/normal BMI group (odds ratio [OR] 2.89 [95% confidence interval (95% CI) 2.42-3.47]), in the overweight BMI group (OR 3.09 [95% CI 2.84-3.36]), and in the obese BMI group (OR 2.65 [95% CI 2.46-2.86]). There was a mildly attenuated effect of the GRS on gout risk in the obese BMI group compared to the overweight BMI group, but no difference in the effect of the GRS between the low/normal BMI and overweight BMI groups, nor between the low/normal BMI and obese BMI groups.

CONCLUSION

The association of a urate GRS with gout is mildly attenuated in obese individuals compared to overweight individuals. However, genetic variants have a strong effect on gout risk in those with overweight and obese BMIs, with an effect similar to that observed in low/normal BMI.

Low-Purine Diet Is More Effective Than Normal-Purine Diet in Reducing the Risk of Gouty Attacks After Sleeve Gastrectomy in Patients Suffering of Gout Before Surgery: a Retrospective Study

BACKGROUND

Obese patients with preoperative gout often suffer of gouty attacks after bariatric surgery (BS), probably due to the lack of an adequate postoperative diet.

OBJECTIVES

The objectives of the study are to assess whether sleeve gastrectomy (SG) is effective in reducing the frequency of gouty attacks and also whether a postoperative low-purine diet (LPD) may further reduce these attacks as compared to a normal-purine diet (NPD) in a series of patients suffering of gout before SG.

METHODS

In this retrospective study, we measured and compared total body weight (TBW), body mass index (BMI), uric acid levels (UAL), anti-gout medication (allopurinol) requirements, and frequency in gouty attacks in 40 patients that underwent SG and who received either a LPD (n = 24) or NPD (n = 16). Compliance in following the prescribed diet was assessed in both groups study.

RESULTS

Before surgery, LPD and NPD patients had hyperuricemia and were receiving allopurinol. One year after SG, LPD and NPD groups showed a significant decrease in serum UAL (p < 0.001 and p = 0.00175, respectively). However, serum UAL decreased more significantly with the LPD compared to the NPD (p < 0.001). Furthermore, while NPD group showed a significant decrease in allopurinol requirements (p = 0.00130) and on the frequency in gouty attacks (p < 0.001), LPD group were off allopurinol therapy and had no gouty attacks 12 months after SG. Both groups showed high compliance in following the prescribed diets.

CONCLUSION

LPD is more effective in reducing the frequency of gouty attacks after SG compared with NPD in patients suffering of gout before surgery.

Gout - An update of aetiology, genetics, co-morbidities and management

Gout is an increasingly common chronic disorder of urate crystal deposition that manifests as flares of acute inflammatory arthritis. Hyperuricaemia is a prerequisite and a fifth of both men and woman are hyperuricaemic. The prevalence of gout is much lower than the prevalence of hyperuricaemia for reasons that are not currently clear. Gout is more common in men than women prior to menopause due to the uricosuric effects of oestrogen, but after menopause the incidence of gout rises substantially in women. Co-morbidities are an important issue in gout, with cardiovascular disease, diabetes mellitus, obesity and chronic kidney disease all common in patients with gout. Environmental factors like diet affect the incidence of gout but there is little evidence to support an emphasis on diet in treating established gout. The diagnosis of gout is often made without the use of joint aspiration and validated diagnostic rules are available for both primary and secondary care as well as classification criteria for research use. The overarching principle of the management of gout with pharmacotherapy is the need to reduce serum urate levels to below a target of 0.30 mmol/L or 0.36 mmol/L depending on whether it is tophaceous or non-tophaceous respectively. The use of allopurinol has been researched extensively and newer strategies for safer effective dosing are now recommended. Newer agents have been introduced for the treatment of gout, including febuxostat and lesinurad. A number of important questions in the field are under current investigation.

Management of hyperuricemia and gout in obese patients undergoing bariatric surgery

BACKGROUND

Hyperuricemia and gout represent important issues in the obese patients. Considering the epidemic trend of overweight and obesity in developed countries, the impact of these conditions is likely to increase. At present, bariatric surgery represents the most effective treatment for the management of severe obesity for reducing weight and the impact of associated comorbidities, but its effects on hyperuricemia and gout have not been fully elucidated.

METHODS

In this narrative review, we discuss the current knowledge about hyperuricemia and gout in obese patients undergoing bariatric surgery. We also suggest a useful approach to prevent gouty attacks in the perioperative period.

RESULTS

Weight loss seems to reduce hyperuricemia in the long-term follow-up, but there is evidence also of a high frequency of acute attacks early after surgery in patients with a diagnosis of gout.

CONCLUSION

Bariatric surgery has a high impact on hyperuricemia and gout. A perioperative approach is suggested, based on appropriate hydration, early physical resumption, urate lowering drugs and nonsteroidal anti-inflammatory drugs (NSAIDs), or colchicine and corticosteroids if NSAIDs are ineffective or not tolerated.

Effects of bariatric surgery on gout incidence in the Swedish Obese Subjects study: a non-randomised, prospective, controlled intervention trial

Objectives

To assess the long-term effect of bariatric surgery on the incidence of gout and hyperuricaemia in participants of the Swedish Obese Subjects (SOS) study.

Methods

This report includes 1982 subjects who underwent bariatric surgery and 1999 obese controls from the SOS study, a prospective intervention trial designed to assess the effect of bariatric surgery compared with conventional treatment. None of the subjects had gout at baseline. An endpoint on gout incidence was created based on information on gout diagnosis and use of gout medications through national registers and questionnaires. Median follow-up for the incidence of gout was about 19 years for both groups. Moreover, the incidence of hyperuricaemia over up to 20 years was examined in a subgroup of participants having baseline uric acid levels <6.8 mg/dL.

Results

Bariatric surgery was associated with a reduced incidence of gout compared with usual care (adjusted HR 0.60, 95% CI 0.48 to 0.75, p<0.001). The difference in absolute risk between groups was 3 percentage points at 15 years, and the number of subjects needed to be treated by bariatric surgery to prevent one incident gout event was 32 (95% CI 22 to 59). The effect of bariatric surgery on gout incidence was not influenced by baseline risk factors, including body mass index. During follow-up, the surgery group had a lower incidence of hyperuricaemia (adjusted HR 0.47, 95% CI 0.39 to 0.58, p<0.001). The difference in absolute risk between groups was 12 percentage points at 15 years, and the number of participants needed to be treated by bariatric surgery to prevent hyperuricaemia was 8 (95% CI 6 to 13).

Conclusions

Bariatric surgery prevents gout and hyperuricaemia in obese subjects.

Trial registration number

NCT01479452; Results.

Bariatric Surgery: What the Rheumatologist Needs to Know

A staggering 76 million adults are obese in the United States. It is known that obesity contributes to increased incidence and worse disease outcomes in many rheumatic conditions. Bariatric surgery has emerged as the most effective treatment modality for the morbidly obese, leading to substantial and sustained weight loss. The purpose of this review article is to summarize the findings of studies investigating the effect of substantial weight loss achieved through bariatric surgery on rheumatic disease and outcomes. Second, with an increasing number of patients undergoing bariatric surgery, it is important for the rheumatologist to have a basic understanding of the commonly performed bariatric procedures and to be aware of important nutritional deficiencies and medication restrictions that apply to this patient population.

Gout: a review of nonmodifiable and modifiable risk factors

Gout is a common inflammatory arthritis triggered by the crystallization of uric acid within the joints. Gout affects millions worldwide and has an increasing prevalence. Recent research has been carried out to better qualify and quantify the risk factors predisposing individuals to gout. These can largely be broken into nonmodifiable risk factors, such as gender, age, race, and genetics, and modifiable risk factors, such as diet and lifestyle. Increasing knowledge of factors predisposing certain individuals to gout could potentially lead to improved preventive practices. This review summarizes the nonmodifiable and modifiable risk factors associated with development of gout.

Impact of bariatric surgery on serum urate targets in people with morbid obesity and diabetes: a prospective longitudinal study

OBJECTIVES

Weight loss leads to reduced serum urate (SU) in people with obesity. However, the clinical relevance of such reductions in SU is unknown. This study examined the impact of non-surgical weight loss and bariatric surgery on SU targets in people with morbid obesity and diabetes.

METHODS

The study was a single-centre, prospective study of 60 people with type 2 diabetes and body mass index ≥35 kg/m(2). Following 6 months of non-surgical weight loss, all participants had laparoscopic sleeve gastrectomy, with a further 1 year of follow-up. Serial SUs were measured throughout the study.

RESULTS

Participants experienced mean (SD) weight loss of 5.5 (4.1) kg prior to surgery and 34.3 (11.1) kg following surgery. SU did not change following non-surgical weight loss (0.38 (0.09) mmol/L at baseline and 0.38 (0.10) mmol/L at follow-up), but increased to 0.44 (0.15) mmol/L in the immediate postoperative period and reduced to 0.30 (0.08) mmol/L 1 year after surgery (p<0.05 for both compared with baseline). Baseline SU, cessation of diuretics, female sex and change in creatinine independently predicted change in SU at the final visit. In participants without gout, SU above saturation levels (≥0.41 mmol/L) were present in 19/48 (40%) at baseline and 1/48 (2%) 1 year after surgery (p<0.0001). In participants with gout, SU above therapeutic target levels (≥0.36 mmol/L) were present in 10/12 (83%) at baseline and 4/12 (33%) 1 year after surgery (p=0.031).

CONCLUSIONS

Clinically relevant reductions in SU occur following bariatric surgery in people with diabetes and WHO class II or higher obesity.