Serum uric acid and self-reported rheumatoid arthritis in a multiethnic adult female population

Association of urinary cotinine-verified smoking status with hyperuricemia: Analysis of population-based nationally representative data

INTRODUCTION

Smoking status based solely on self-reporting is unreliable and might be inaccurate, particularly among women. This study investigated the association between urinary cotinine-verified smoking status and hyperuricemia in a nationwide Korean population.

METHODS

This study included 5329 participants aged ≥19 years with information on smoking status, urine cotinine levels and serum uric acid. We determined smoking status according to self-reports and urinary cotinine levels. Multivariate linear regression analysis was used to measure the association between smoking exposure and serum uric acid levels. The effects of smoking on hyperuricemia were evaluated by multivariate logistic regression analysis.

RESULTS

Biochemically verified active and passive smokers comprised 22% (38.7% of men and 8.8% of women) and 12.3% (11.9% of men and 12.6% of women) of the study population, respectively. While reclassification rate of active smokers was 1.4% in men, 31.8% of cotinine-verified female active smokers were self-reported never smokers. Higher uric acid levels were observed with increased tobacco exposure among women (p-trend=0.007) but not among men. After adjusting for confounders, the risk of hyperuricemia increased with tobacco exposure only in women (p-trend=0.016).

CONCLUSIONS

Cotinine-verified smoking status was associated with increased serum uric acid and hyperuricemia in a dose-response manner only in women. This study might provide evidence to support the importance of smoking cessation in women with gout and further studies are necessary to elucidate the underlying mechanism of the observed association.

An association of smoking with serum urate and gout: A health paradox

BACKGROUND

The potential effect of cigarette smoking on levels of serum urate and risk of gout has been considered by a large number of studies, either as the primary variable of interest or as a covariate.

METHODS

Here we systematically review the published evidence relating to the relationship of smoking with serum urate, hyperuricaemia, and gout.

RESULTS

Many studies have reported that smoking reduces serum urate, however, the evidence has not been conclusive with other studies pointing to the opposite or no effect. It has also been suggested that smoking reduces the risk of gout, although there is some evidence to contradict this finding.

CONCLUSION

A consensus has yet to be reached as to the effect of smoking on serum urate levels and the risk of gout.

Evidence-based recommendations for the diagnosis and management of rheumatoid arthritis for non-rheumatologists: Integrating systematic literature research and expert opinion of the Thai Rheumatism Association

AIM

Rheumatoid arthritis (RA) is a chronic inflammatory joint disease leading to joint damage, functional disability, poor quality of life and shortened life expectancy. Early diagnosis and aggressive treatment are a principal strategy to improve outcomes. To provide best practices in the diagnosis and management of patients with RA, the Thai Rheumatism Association (TRA) developed scientifically sound and clinically relevant evidence-based recommendations for general practitioners, internists, orthopedists, and physiatrists.

METHODS

Thirty-seven rheumatologists from across Thailand formulated 18 clinically relevant questions: three for diagnosis, 10 for treatments, four for monitoring, and one for referral. A bibliographic team systematically reviewed the relevant literature on these topics up to December 2013. A set of recommendations was proposed based on the results of systematic reviews combined with expert opinions. Group consensus was achieved for all statements and recommendations using the nominal group technique.

RESULTS

A set of recommendations was proposed. For diagnosis, either American College of Rheumatology (ACR) 1987 or ACR/European League Against Rheumatism 2010 classification criteria can be applied. For treatment, nonsteroidal anti-inflammatory drugs, glucocorticoid, and disease-modifying antirheumatic drugs, including antimalarials, methotrexate and sulfasalazine are recommended. Physiotherapy should be suggested to all patients. Tight control strategy and monitoring for efficacy and side effects of treatments, as well as indications for referral to a rheumatologist are provided.

CONCLUSIONS

These evidence-based recommendations provide practical guidance for diagnosis, fundamental management and referral of patients with RA for non-rheumatologists. However, it should be incorporated with clinical judgments and decisions about care for each individual patient.

Effects of Sodium Glucose Cotransporter-2 Inhibitors on Serum Uric Acid in Type 2 Diabetes Mellitus

Hyperuricemia has been linked to metabolic syndrome, cardiovascular disease, and chronic kidney disease. Hyperuricemia and type 2 diabetes mellitus were inter-related, type 2 diabetes mellitus was more at risk of having a higher serum uric acid level, and also individuals with higher serum uric acid had higher risk of developing type 2 diabetes in the future. Insulin resistance seems to play an important role in the causal relationship between metabolic syndrome, type 2 diabetes, and hyperuricemia. Oral diabetic drugs that would have additional beneficial effects on reducing serum uric acid levels are of importance. Selective SGLT2 inhibitors were extensively studied in type 2 diabetes mellitus and were found to have improvement of glycemic control, in addition to their proven metabolic effects on weight and blood pressure. Additional beneficial effect of SGLT2 inhibitors on serum uric acid level reduction is investigated. Recently, data have been accumulating showing that they have additional beneficial effects on serum uric acid reduction. As for the postulated mechanism, serum uric acid decreased in SGLT2 inhibitor users as a result of the increase in the urinary excretion rate of uric acid, due to the inhibition of uric acid reabsorption mediated by the effect of the drug on the GLUT9 isoform 2, located at the collecting duct of the renal tubule.

Patients with Rheumatoid Arthritis Show Altered Lipoprotein Profiles with Dysfunctional High-Density Lipoproteins that Can Exacerbate Inflammatory and Atherogenic Process

Objective

In order to identify putative biomarkers in lipoprotein, we compared lipid and lipoprotein properties between rheumatoid arthritis (RA) patients and control with similar age.

Methods

We analyzed four classes of lipoproteins (VLDL, LDL, HDL₂, HDL₃) from both male (n = 8, 69±4 year-old) and female (n = 25, 53±7 year-old) rheumatoid arthritis (RA) patients as well as controls with similar age (n = 13).

Results

Although RA group showed normal levels of total cholesterol (TC), low-density lipoprotein (LDL)-cholesterol, and glucose, however, the RA group showed significantly reduced high-density lipoprotein (HDL)-C level and ratio of HDL-C/TC. The RA group showed significantly elevated levels of blood triglyceride (TG), uric acid, and cholesteryl ester transfer protein (CETP) activity. The RA group also showed elevated levels of advanced glycated end (AGE) products in all lipoproteins and severe aggregation of apoA-I in HDL. As CETP activity and TG contents were 2-fold increased in HDL from RA group, paraoxonase activity was reduced upto 20%. Electron microscopy revealed that RA group showed much less HDL₂ particle number than control. LDL from the RA group was severely oxidized and glycated with greater fragmentation of apo-B, especially in female group, it was more atherogenic via phagocytosis.

Conclusion

Lipoproteins from the RA patients showed severely altered structure with impaired functionality, which is very similar to that observed in coronary heart patients. These dysfunctional properties in lipoproteins from the RA patients might be associated with high incidence of cardiovascular events in RA patients.

Evaluation of serum magnesium, lipid profile and various biochemical parameters as risk factors of cardiovascular diseases in patients with rheumatoid arthritis

BACKGROUND

Rheumatoid arthritis (RA) is chronic inflammatory disease, associated with increased risk of cardiovascular diseases (CVD) than the general population. Chronic inflammatory conditions are likely to alter magnesium level and various biochemical parameters.

OBJECTIVES

To study the probable changes in serum magnesium, lipid profile and various biochemical parameters and to assess risk factors of CVD in newly diagnosed RA patients compared to controls.

MATERIALS AND METHODS

We studied 50 newly diagnosed RA adult patients and 50 healthy individuals as controls. Serum magnesium, calcium, lipid profile, uric acid and other biochemical parameters were measured in study subjects. Results were expressed as Mean ± SD and compared between RA subjects and controls by Independent sample t-test and Pearson correlation.

RESULTS

We found decreased serum magnesium and calcium in RA subjects compared to the controls (p < 0.001). RA subjects had atherogenic lipid profile characterized by elevated total cholesterol (p = 0.054), LDL cholesterol (p = 0.008) and decreased HDL cholesterol (p <0.001). Serum uric acid was higher in RA cases compared to controls (p = 0.025). Serum magnesium was negatively correlated with total cholesterol, LDL cholesterol and positively correlated with HDL cholesterol in RA cases.

CONCLUSION

Decreased magnesium level, dyslipidemia and increased uric acid observed in our study together may be more potent risk factors for CVD in newly diagnosed RA subjects. We recommend that serum magnesium should be investigated as a part of cardiovascular risk management in RA. We suggest that decreased serum magnesium and increased serum uric acid may be considered as nontraditional risk factors of CVD in RA. Further prospective studies are needed to confirm the impact of inflammation on various biochemical parameters and cardiovascular outcomes in patients with RA.

Review of hyperuricemia as new marker for metabolic syndrome

Hyperuricemia has long been established as the major etiologic factor in gout. In recent years, a large body of evidence has accumulated that suggests that hyperuricemia may play a role in the development and pathogenesis of a number of metabolic, hemodynamic, and systemic pathologic diseases, including metabolic syndrome, hypertension, stroke, and atherosclerosis. A number of epidemiologic studies have linked hyperuricemia with each of these disorders. In some studies, therapies that lower uric acid may prevent or improve certain components of the metabolic syndrome. There is an association between uric acid and the development of systemic lupus erythematosus; the connection between other rheumatic diseases such as rheumatoid arthritis and osteoarthritis is less clear. The mechanism for the role of uric acid in disorders other than gout is not well established but recent investigations point towards systemic inflammation induced by urate, as the major pathophysiological event common to systemic diseases, including atherosclerosis.