Coffee consumption and gout: a Mendelian randomisation study

Coffee Consumption Reduces Gout Risk Independently of Serum Uric Acid Levels: Mendelian Randomization Analyses Across Ancestry Populations

Objective

The effects of coffee consumption on serum uric acid (SUA) levels and gout risk are controversial. There have hitherto been no reports based on Mendelian randomization (MR) analysis of its effects that consider pleiotropy. Here, we evaluated the effects of coffee consumption across ancestry populations, taking pleiotropy into account.

Methods

We performed the first MR analyses for coffee consumption on SUA levels and gout, considering pleiotropy. We used the following summary statistics of genome‐wide association studies from a Japanese population: habitual coffee consumption (152,634 subjects), gout (3053 cases and 4554 controls), and SUA levels (121,745 subjects). In addition to fixed‐effect inverse variance weighted (IVW) meta‐analysis, we performed a robust evaluation of heterogeneity and removed several instruments for reasons of possible pleiotropy. Previous European datasets were also reevaluated while heterogeneity was considered.

Results

Habitual coffee consumption was significantly and inversely associated with gout (odds ratio [OR] = 0.29, 95% confidence interval [95% CI]: 0.16‐0.51, P = 1.9 × 10⁻⁵) in random‐effect IVW (P_het = 5.5 × 10⁻¹⁹). Excluding pleiotropic instruments, the protective effect on gout was confirmed in fixed‐effect IVW analysis (OR = 0.75, 95% CI: 0.58‐0.97, P = 0.026) without heterogeneity (P_het = 0.39). However, we observed no significance in the previous European datasets when heterogeneity was considered. Associations were not observed between coffee consumption and SUA levels in either ancestry in MR analyses that considered pleiotropy. Multivariable MR analysis showed that increased coffee consumption significantly reduced gout risk, even after adjusting for SUA levels (OR = 0.50, 95% CI: 0.31‐0.81, P = 0.0046).

Conclusion

With pleiotropy taken into account, our MR analyses revealed that coffee consumption can causally reduce gout risk, and that it may reduce gout risk independently of SUA levels.

The Relationship between Alcohol Consumption and Gout: A Mendelian Randomization Study

Gout is a disease that manifests itself after decades of following a high-purine diet, with excessive alcohol consumption assumed to be one of the main contributors to the development of the disease. This study performs a Mendelian randomization (MR) analysis to determine whether alcohol consumption causally affects the risk of developing both hyperuricemia and gout. The results indicate that genetically predicted drinks consumed per week have no causal effect on neither the risk of gout (p = 0.35), nor serum uric acid levels (p = 0.73). For MR analysis in the other direction, genetic risk of gout was significantly associated with drinks per week (p = 0.03). Furthermore, the results of the MR analysis were verified in a cohort of individuals diagnosed with hyperuricemia and gout, comprising of alcohol-consuming and alcohol-abstaining subgroups. When split by alcohol status, the serum uric acid levels failed to show a significant difference in both gout (p = 0.92) and hyperuricemia (p = 0.23) subgroups. Overall, the results suggest that increased alcohol consumption does not play a causal role in the development of gout.

Effect of Serum Ferritin on the Association Between Coffee Intake and Hyperuricemia Among American Women: The National Health and Nutrition Examination Survey

Background

Accruing evidence suggests an inverse relationship between coffee intake and serum uric acid. The mechanism(s) explaining this inverse relationship remains elusive. The aim of this study was to assess if the association between coffee intake and hyperuricemia is mediated via serum ferritin in women.

Methods

We pooled data from the 2003 to 2006 National Health and Nutrition Examination Survey (NHANES). We included women with complete information on all key variables. Coffee intake was classified as none, <1 cup/day, 1-3 cups/day, and ≥4 cups/day. Hyperuricemia was defined as serum uric acid >5.7 mg/dL. We assessed the association between coffee intake and hyperuricemia using logistic regression. Path analysis was used to examine whether serum ferritin mediated the effect of coffee on hyperuricemia.

Results

Among 2,139 women (mean age: 31.2 years [SD: 9.2]), mean serum uric acid was 4.4 mg/dL (SD: 1.0), and 227 (10.6%) had hyperuricemia. In multivariate logistic regression models, intake of ≥4 cups/day of coffee was associated with lower odds of hyperuricemia (OR 0.28 [95% CI: 0.09, 091], P=0.035). The total direct and indirect effect of coffee on hyperuricemia via serum ferritin was −0.16, P=0.009 and −8.1 × 10⁻³, P=0.204, respectively.

Conclusion

Among women, moderate coffee consumption was inversely related to hyperuricemia by direct effect, rather than indirectly through the effects of serum ferritin. These findings suggest that serum ferritin does not mediate the inverse association between coffee and hyperuricemia in women.

Genetics of hyperuricemia and gout: Insights from recent genome-wide association studies and Mendelian randomization studies

Gout is the most common form of inflammatory arthritis in adults. Elevation serum uric acid (SUA) concentration is known to be the key to gout pathogenesis. Since the first genome-wide association study (GWAS) for SUA was performed in 2007, the number of gene loci known to be associated with hyperuricemia and gout has grown rapidly. GWASs and Mendelian randomization studies have also reported numerous novel results regarding the genetics of hyperuricemia and gout since 2018. We concisely review recent advances in scholarship on the effects of genetics on hyperuricemia and gout risk. We also review data from genetic association studies in Taiwan and perform GWASs of SUA levels among Taiwan Biobank participants.

Impact of Secukinumab on Patient-Reported Outcomes in the Treatment of Ankylosing Spondylitis: Current Perspectives

Ankylosing spondylitis (AS) is a chronic rheumatic disease involving inflammation of the joints and spine, which carries a substantial, life-long burden for the patient. Secukinumab is a fully human anti-interleukin-17A monoclonal antibody, approved in the USA and EU for the treatment of AS. In this narrative review, we searched PubMed with the aim of consolidating the recent literature regarding the impact of secukinumab on patient-reported outcomes in patients with AS. A large clinical trial program has demonstrated the efficacy of secukinumab in relieving the signs and symptoms of AS. Most importantly from a patient perspective, secukinumab has produced improvements in a range of patient-reported outcomes (PROs), including pain, fatigue, quality of life and work productivity, as well as composite measures including patient-reported elements, such as the Bath indices and Assessment of SpondyloArthritis international Society (ASAS) response criteria. Benefits to patients were rapid, and sustained in the long term (up to 5 years). The positive effect of secukinumab was seen regardless of whether patients had previously been treated with anti-tumor necrosis factor (TNF) therapies. Greater improvements in PROs were associated with patients being anti-TNF-naïve, of a younger age, with shorter disease duration and higher objective measures of inflammation at baseline. The available real-world evidence suggests that the effects of secukinumab on PROs in clinical practice are consistent with those seen in clinical trials, and evidence in a real-world setting continues to be collected.

Socioeconomic differences in hyperuricemia and gout: a systematic review and meta-analysis

PURPOSE

There are multiple risk factors have different influence on the disorder. However, the risk of hyperuricemia and gout in different socioeconomic status (SES) remains unclear. Recent studies provided results that contradicted to former studies. We aimed to perform a systematic review and meta-analysis of evidence to date and to assess the associations between SES and hyperuricemia or gout worldwide.

METHODS

We searched MEDLINE, EMBASE, and Web of Science databases to identify studies that investigated the association between SES and hyperuricemia or gout. Studies that presented risk estimates were included. We conducted meta-analyses using random effects to combine unadjusted and adjusted effect estimates.

RESULTS

Data from 14 studies were included, 9 provided data about hyperuricemia and 5 provided gout. Overall, there was an association between higher educational level and a higher risk of hyperuricemia (POR = 1.38, 95% CI 1.04-1.73) but lower risk of gout (POR = 0.59, 95% CI 0.47-0.71). Subgroup meta-analysis showed no association between all SES measures and hyperuricemia or gout in males or females.

CONCLUSIONS

Our study suggested that the associations between SES and hyperuricemia gout are different. Higher educational level was related to a higher risk of hyperuricemia but lower risk of gout. Given the limitations of our study, future studies are needed to investigate specific mechanisms underlying the relationship among SES differences in hyperuricemia and gout. Strategies to prevent and control SES inequalities in hyperuricemia and gout should be explored and adopted.

Long-Term Effectiveness of Secukinumab in Patients with Axial Spondyloarthritis

Objectives

The primary aim of our study was to evaluate long-term efficacy of secukinumab (SCK) in patients with axial spondyloarthritis (axSpA); secondary aims were to evaluate drug retention rate and to identify differences in the clinical and laboratory assessment according to axSpA clinical features, dosage administered, and biologic treatment lines. Patients and Methods. We collected clinical, demographical, and treatment data from 39 patients affected by axSpA consecutively treated with SCK. Laboratory assessment was based on inflammation parameters; clinical assessment was performed with the Ankylosing Spondylitis Disease Activity Score- (ASDAS-) CRP and Bath Ankylosing Spondylitis Disease Activity Index (BASDAI). Data were recorded at baseline and every 3 months for the first year and then every 6 months in the second year.

Results

Twelve males and 27 females were enrolled; both BASDAI and ASDAS-CRP showed a statistically significant reduction during the observation period (p < 0.0001 and p < 0.0001, respectively). C-reactive protein significantly decreased (p = 0.006), with significant reduction at the post hoc analysis between baseline and both 6-month evaluation (p = 0.02) and 24-month visit (p = 0.036). No statistical significance was observed in BASDAI and ASDAS-CRP improvement (p = 0.482 and p = 0.164, respectively) between different dosages administered. No significant differences emerged in the BASDAI and ASDAS-CRP variations between biologic-naïve patients and subjects previously failing to tumour necrosis factor (TNF) inhibitors (p = 0.53 and p = 0.148, respectively). At the end of our observation, 7 out of 39 patients discontinued SCK. The global retention rate at the end of the study period was 78.2%, without any significant differences between biologic-naïve and anti-TNF-failure patients (p = 0.619) or between subjects administered with different SCK dosages (p = 0.614). No adverse events were reported.

Conclusions

In our cohort, SCK has proved a remarkable effectiveness regardless biologic treatment line and dosages employed. As suggested by the notable drug retention rate, SCK has been able to maintain its effectiveness over a considerable long period of treatment.

Association between habitual coffee consumption and multiple disease outcomes: A Mendelian randomisation phenome-wide association study in the UK Biobank

BACKGROUND

Coffee is the most commonly consumed beverage in the world after water, however the debate as to whether coffee consumption is beneficial or detrimental to health continues. Current evidence of the link between coffee and health outcomes is predominately observational, thus subject to methodological issues such a confounding and reverse causation.

METHODS

This Mendelian randomisation phenome-wide association study (MR-PheWAS) used information from up to 333,214 participants of White-British ancestry in the UK Biobank to examine the causal association between genetically instrumented habitual coffee consumption and the full range of disease outcomes. We constructed a genetic risk score for habitual coffee consumption and screened for associations with disease outcomes across 1117 case-control series. All signals under false discovery rate controlled threshold (5.8 × 10^-4) were followed by Mendelian randomisation (MR) analyses, with replication in independent data sources where possible.

RESULTS

The initial phenome-wide association analysis identified signals for 13 outcomes representing five distinct diseases. The strongest signal was seen for gout (P = 2.3 × 10^-12), but there was notable pleiotropy (P_distortion <0.001) and MR analyses did not support an association with habitual coffee consumption (inverse variance weighted MR OR 0.41, 95% CI 0.08 to 2.25, P = 0.31). Support for a possible causal relationship between habitual coffee consumption was only obtained for four distinct disease outcomes, including an increased odds of osteoarthrosis (OR 1.23, 95% CI 1.11 to 1.35), other arthropathies (OR 1.22, 95% CI 1.12 to 1.33) and overweight (OR 1.28, 95% CI 1.05 to 1.56), and a lower odds of postmenopausal bleeding (OR 0.72, 95% CI 0.63 to 0.82). Evidence for an association between habitual coffee consumption and these four diseases was also supported by phenotypic associations with self-reported coffee consumption.

CONCLUSIONS

This large-scale MR-PheWAS provided little evidence for notable harm or benefit with respect to higher habitual coffee consumption. The only evidence for harm was seen with respect to osteoarthrosis, other arthropathies and obesity.

Evaluation of the Feasibility of a Web-Based Survey to Assess Patient-Reported Symptom Improvement and Treatment Satisfaction Among Patients with Psoriatic Arthritis Receiving Secukinumab

BACKGROUND AND OBJECTIVE

Patient perspectives regarding treatment experience and satisfaction may be useful for clinicians when making treatment strategies. This US-based study assessed the feasibility of evaluating real-world, patient-reported narratives regarding symptom improvement and treatment satisfaction among patients with psoriatic arthritis treated with secukinumab.

METHODS

A cross-sectional, web-based survey collected data on demographics, disease characteristics, symptoms before and after secukinumab use, and treatment satisfaction with secukinumab.

RESULTS

Of 2755 patients screened, 200 patients with psoriatic arthritis were eligible and included in the analysis. Their mean age was 36.0 (standard deviation, 10.0) years; 55.5% were male and 75.0% were white. Most (87.5%) were biologic experienced; the primary reason for discontinuation of their previous treatment was lack of effectiveness (28.6%). Most patients (79.9%) reported overall psoriatic arthritis symptom improvement after secukinumab initiation compared with before secukinumab initiation; a similar trend was observed for all individual symptoms evaluated. Approximately half of patients reported improvement within 4 weeks after starting secukinumab treatment, and > 90% reported improvement within 6 months. Most patients (≥ 96%) expressed overall satisfaction with secukinumab regarding symptom improvement, speed of symptom improvement, frequency of administration, method of administration, ease of use, patient support services, and side effects, if any.

CONCLUSIONS

Patient-reported perspectives may be feasibly collected to provide insights into treatment experience and satisfaction of secukinumab. Most patients with psoriatic arthritis in our real-world study experienced symptom improvement after initiating secukinumab; > 50% of patients reported symptom improvement within 4 weeks. Additionally, almost all patients reported satisfaction with secukinumab treatment.

Genetic and epigenetic alteration of the programmed cell death 1 in rheumatoid arthritis

BACKGROUND

Rheumatoid arthritis (RA) is an autoimmune disease where both genetics and epigenetics are contributing factors. In order to discover genetic and epigenetic associations with RA and its phenotypes, we analysed RNA expression, DNA variations and DNA methylation of programmed cell death 1 (PDCD1) in a cohort of RA patients and healthy controls.

METHODS

RA patients (n = 206) and healthy controls (n = 234) were included for analysis of PDCD1 expression, PDCD1 polymorphisms and PDCD1 methylation. Differences in continuous variables between groups were compared by applying t tests. Associations between phenotypes and genotypes were evaluated with contingency tables. Sensitivity analyses were conducted to confirm the robustness of results, considering potential confounding factors and different treatment response definitions. Odds ratio (OR) and 95% confidence interval (95% CI) were calculated.

RESULTS

Higher expression of PDCD1 was found in RA compared to controls (P < 0.001), with similar PDCD1 polymorphisms in RA and controls. rs36084323 decreased inadequate response to conventional synthetic disease-modifying antirheumatic drugs (OR = 0.37, 95% CI = 0.19-0.72, P = 0.003), and rs41386349 increased rheumatoid factor seropositivity (OR = 11.89, 95% CI = 1.57-89.87, P = 0.003). Sensitivity analysis adjusting for further potential confounders and using different treatment response definition indicated similar results. Additionally, DNA methylation change at regulatory region of PDCD1 was detected in RA (P = 0.036).

CONCLUSION

Altogether, this was the first study to suggest genetic and epigenetic changes of PDCD1 in RA subsets and RA. Independent prospective cohorts are awaited to address the implications of these genetic and epigenetic changes in disease pathogenesis and phenotypes of RA.

A Pilot Study to Assess the Feasibility of a Web-Based Survey to Examine Patient-Reported Symptoms and Satisfaction in Patients with Ankylosing Spondylitis Receiving Secukinumab

Purpose

This real-world study evaluated the feasibility of assessing patient-reported symptom improvement and treatment satisfaction using a web-based survey among patients with ankylosing spondylitis (AS) treated with secukinumab.

Methods

This cross-sectional, web-based survey collected data on demographics, symptoms, treatment history, and treatment satisfaction from US patients with AS who were receiving secukinumab at survey participation. Patients reported AS symptoms experienced before and after secukinumab initiation, time to symptom improvement, and satisfaction with secukinumab treatment.

Results

Of 2755 patients screened, 200 with AS were included in the analysis. The mean (SD) age of patients was 34.4 (10.6) years; 86.5% were biologic experienced. Most (74.0%) reported overall improvement (“a little,” “moderately,” or “much better”) in AS symptoms since secukinumab initiation compared with before secukinumab initiation; a similar trend was observed for all the individual symptoms analyzed (pain disrupting sleep, fatigue, morning stiffness, pain and stiffness in lower back or neck, sore areas other than joints, and ankle or heel pain [indicating enthesitis]). Approximately 41.9% of patients reported overall symptom improvement within 4 weeks of secukinumab treatment. Most expressed overall satisfaction (“very,” “mostly,” or “somewhat satisfied”) with secukinumab regarding symptom improvement (99.0%), speed of symptom improvement (97.0%), frequency and method of administration (96.0% and 91.5%, respectively), ease of use (93.5%), patient support services (97.0%), and side effects, if any (93.0%).

Conclusion

Most patients reported overall symptom improvement and satisfaction with treatment. Our study indicates that patient-reported perspectives may be feasibly collected using a web-based survey to provide insights into treatment experience and satisfaction.

Electronic supplementary material

The online version of this article (10.1007/s40801-019-0154-4) contains supplementary material, which is available to authorized users.

Coffee Consumption and Risk of Dementia and Alzheimer's Disease: A Dose-Response Meta-Analysis of Prospective Studies

Coffee consumption is associated with a reduced risk of several diseases but uncertainty remains about the influence of coffee consumption on the risk of dementia. We performed a dose-response meta-analysis to summarize the prospective data on coffee consumption and associated risk of dementia and Alzheimer’s disease. We identified studies by searching PubMed (from January 1966) and Web of Science (from January 1945) through 4 October 2018 and by scrutinizing the reference lists of pertinent publications. Two researchers independently reviewed the literature. Results were combined using a restricted cubic spline random-effects dose-response meta-analysis based on a one-stage approach. Eight relevant prospective studies were identified. These studies included 7486 dementia cases diagnosed among 328,885 individuals during an average follow-up of 4.9–25 years. Meta-analysis of all eight studies indicated no statistically significant association between coffee consumption and the risk of dementia and no deviations from a linear trend (p = 0.08). The relative risk of dementia per 1 cup/day increment of coffee consumption was 1.01 (95% confidence interval (CI) 0.98–1.05; p = 0.37). Meta-analysis of five studies that focused on Alzheimer’s disease revealed no association between coffee consumption and Alzheimer’s disease and no deviations from a linear trend (p = 0.79). The relative risk of Alzheimer’s disease per 1 cup/day increment of coffee consumption was 1.01 (95% confidence interval 0.95–1.07; p = 0.80). These results do not support an association between coffee consumption and an increased risk of overall dementia or Alzheimer’s disease specifically, but further research on the association of coffee consumption with dementia risk is needed.

Mendelian Randomization Studies of Coffee and Caffeine Consumption

Habitual coffee and caffeine consumption has been reported to be associated with numerous health outcomes. This perspective focuses on Mendelian Randomization (MR) approaches for determining whether such associations are causal. Genetic instruments for coffee and caffeine consumption are described, along with key concepts of MR and particular challenges when applying this approach to studies of coffee and caffeine. To date, at least fifteen MR studies have investigated the causal role of coffee or caffeine use on risk of type 2 diabetes, cardiovascular disease, Alzheimer's disease, Parkinson's disease, gout, osteoarthritis, cancers, sleep disturbances and other substance use. Most studies provide no consistent support for a causal role of coffee or caffeine on these health outcomes. Common study limitations include low statistical power, potential pleiotropy, and risk of collider bias. As a result, in many cases a causal role cannot confidently be ruled out. Conceptual challenges also arise from the different aspects of coffee and caffeine use captured by current genetic instruments. Nevertheless, with continued genome-wide searches for coffee and caffeine related loci along with advanced statistical methods and MR designs, MR promises to be a valuable approach to understanding the causal impact that coffee and caffeine have in human health.

Mediation analysis to understand genetic relationships between habitual coffee intake and gout

Background

Increased coffee intake is associated with reduced serum urate concentrations and lower risk of gout. Specific alleles of the GCKR, ABCG2, MLXIPL, and CYP1A2 genes have been associated with both reduced coffee intake and increased serum urate in separate genome-wide association studies (GWAS). The aim of this study was to determine whether these single nucleotide polymorphisms (SNPs) influence the risk of gout through their effects on coffee consumption.

Methods

This research was conducted using the UK Biobank Resource. Data were available for 130,966 European participants aged 40–69 years. Gout status and coffee intake were tested for association with four urate-associated SNPs: GCKR (rs1260326), ABCG2 (rs2231142), MLXIPL (rs1178977), and CYP1A2 (rs2472297). Multiple regression and path analysis were used to examine whether coffee consumption mediated the effect of the SNPs on gout risk.

Results

Coffee consumption was inversely associated with gout (multivariate adjusted odds ratio (95% confidence interval (CI)) for any coffee consumption 0.75 (0.67–0.84, P = 9 × 10⁻⁷)). There was also evidence of a dose-effect with multivariate adjusted odds ratio (95% CI) per cup consumed per day of 0.85 (0.82–0.87, P = 9 × 10⁻³²). The urate-increasing GCKR, ABCG2, MLXIPL, and CYP1A2 alleles were associated with reduced daily coffee consumption, with the strongest associations for CYP1A2 (beta −0.30, P = 8 × 10⁻⁴⁰), and MLXIPL (beta −0.17, P = 3 × 10⁻⁸), and weaker associations for GCKR (beta −0.07, P = 3 × 10⁻¹⁰) and ABCG2 (beta −0.09, P = 2 × 10⁻⁹). The urate-increasing GCKR and ABCG2 alleles were associated with gout (multivariate adjusted p < 5 × 10⁻⁸ for both), but the urate-increasing MLXIPL and CYP1A2 alleles were not. In mediation analysis, the direct effects of GCKR and ABCG2 accounted for most of the total effect on gout risk, with much smaller indirect effects mediated by coffee consumption.

Conclusion

Coffee consumption is inversely associated with risk of gout. Although alleles at several SNPs associate with both lower coffee consumption and higher risk of gout, these SNPs largely influence gout risk directly, rather than indirectly through effects on coffee consumption.

Electronic supplementary material

The online version of this article (10.1186/s13075-018-1629-5) contains supplementary material, which is available to authorized users.