Prevalence, incidence, and risk factors of malignancy in patients with rheumatoid arthritis: a nationwide cohort study from Korea

Incidence of Malignancies and the Association with Biological Disease-Modifying Antirheumatic Drugs in Japanese Patients with Rheumatoid Arthritis: A Time-Dependent Analysis from the IORRA Patient Registry

INTRODUCTION

Patients with rheumatoid arthritis (RA) may have an increased malignancy risk versus the general population, potentially elevated by biological disease-modifying antirheumatic drug (bDMARD) use. Using patient registry data, we determined malignancy risk, stratified by bDMARD use, among Japanese patients with RA versus the Japanese general population and investigated whether bDMARD use is a time-dependent risk factor for the development of malignancy.

METHODS

Patients aged ≥ 18 years with ≥ 2 data entries of RA in the IORRA (Institute of Rheumatology, Rheumatoid Arthritis) patient registry, enrolled from January 2013-December 2018, were identified ('All RA' cohort). Patients were stratified into bDMARD (≥ 1 bDMARD received) or non-bDMARD (no history of bDMARDs) sub-cohorts. Malignancy incidence rates and standardized incidence ratios (SIRs) with 95% confidence intervals (CIs) versus the Japanese general population were calculated. Risk of RA medication use was analyzed using a time-dependent Cox proportional hazards model, after adjusting for covariates.

RESULTS

A total of 8020 patients were identified for the All RA cohort; 2187 and 5833 for the bDMARD and non-bDMARD sub-cohorts, respectively. For all three cohorts, incidence of overall malignancies was similar versus the Japanese general population. Incidence of specific malignancies was also similar, but incidence of lymphoma was higher for all three cohorts (SIRs [95% CIs] 3.72 [2.71-4.93], 5.97 [3.34-9.59], and 2.79 [1.82-4.02], respectively). In the bDMARD sub-cohort, no increase in SIRs was observed for other site-specific malignancies. In the All RA cohort, use of methotrexate, tacrolimus, glucocorticoids, non-steroidal anti-inflammatory drugs, and bDMARDs were not associated with the risk of overall malignancy; the hazard ratio (95% CI) was 1.36 (0.96-1.93) for bDMARD use. Increased disease activity was a time-dependent risk factor of overall malignancy with a hazard ratio (95% CI) of 1.35 (1.15-1.59).

CONCLUSIONS

The use of bDMARDs was not a time-dependent risk factor for malignancy.

Rheumatoid arthritis reduces the risk of colorectal cancer through immune inflammation mediation

There is a close relationship between immune-mediated inflammation and cancer, and there is still controversy over whether rheumatoid arthritis (RA) increases the risk of malignancy. We first used Mendelian randomization (MR) analysis to explore the potential causal relationship between RA and pan-cancer. And verify the effect of immune-mediated inflammation on cancer through intermediate MR analysis. Then we extracted the standardized incidence rate of malignancy in RA patients relative to the general population through large-scale meta-analysis. Finally, we performed pan-cancer analysis on the RA related genes obtained from MR analysis. And perform immune related analysis on key genes to reveal the association between RA and malignancy. The MR analysis demonstrated a negative correlation between RA and pan-cancer (p = 0.008). Autoimmune traits were the main mediating variable for the causal relationship between RA and pan-cancer. Based on the results of the meta-analysis, we validated that RA reduces the risk of developing colorectal cancer (SIR = 0.69, 95% CI 0.53-0.85). Pan-cancer analysis also showed that high expression of RA related genes was negatively correlated with colon adenocarcinoma. IL6R was the gene with the highest correlation among them, and its correlation with immune cells was higher in colorectal cancer than in other malignancy. Our MR study provides evidence that RA was associated with reduced risk of colorectal cancer. This effect is caused by immune-mediated inflammation, with IL6R being a key regulatory gene.

A narrative review of the comparative safety of disease-modifying anti-rheumatic drugs used for the treatment of rheumatoid arthritis

INTRODUCTION

Disease-modifying anti-rheumatic drugs (DMARDs) have improved the outcomes of patients with rheumatoid arthritis (RA). DMARDs are classified into three categories: conventional synthetic DMARDs, biological DMARDs (including biosimilars), and targeted synthetic DMARDs. DMARDs, by way of their effect on the immune system, are associated with increased risk of adverse events, including infections, malignancies, cardiovascular disease, gastrointestinal perforations, and other less common events.

AREAS COVERED

In this narrative literature review performed with searches of the PubMed database from 1 January 2010 through 1 January 2023, we compare the risk of safety events between DMARDs using data from both randomized clinical trials and observational studies.

EXPERT OPINION

DMARD use in RA is associated with higher rates of serious infections, tuberculosis reactivation, opportunistic infections, and possibly malignancies. Specific biologic DMARDs and higher doses are associated with elevated risks of various adverse events (gastrointestinal perforations, thromboembolism, serious infection). Shared decision-making is paramount when choosing a treatment regimen for patients based on their own comorbidities. JAKi are the newest class of medications used for RA with robust safety data provided in clinical trials. However, more real-world evidence and phase-IV pharmacovigilance data are needed to better understand comparative safety profile of DMARDs in RA.

Hydroxychloroquine had neutral effect on long-term risk of malignancy in rheumatoid arthritis patients: A population-based retrospective cohort study

BACKGROUND

The cancer risk in rheumatoid arthritis (RA) patients has been discussed. Hydroxychloroquine (HCQ) may exert protective effects against malignancy. The study investigated the association between HCQ use and the risk of subsequent malignancy in RA patients.

METHODS

Catastrophic illness certificated RA patients were extracted from the National Health Insurance Research Database. The index date was set 180 days after the RA diagnosis date to avoid immortal time bias. Two groups were matched in a 1-to-1 ratio by propensity score regarding age, gender, index date, relevant comorbidities, and comedication. HCQ users prior to the diagnosis of RA were exempted to ensure compliance with the new-user design. Cancers diagnosed before or less than 180 days after the index date were excluded to mitigate protopathic bias. The study adopted the Kaplan-Meier curve and Cox proportional hazards model to examine the association between HCQ use and cancer risk. The assumption of proportional hazard was also tested.

RESULTS

Based on strict criteria, we included 492 eligible RA patients and divided them into study and control groups (N = 246 in each group). HCQ users exhibited a neutral risk of cancer relative to the controls (adjusted hazard ratio, 0.99; 95% CI, 0.44-2.21, p > .05). The assumption of proportional hazard was not violated.

CONCLUSION

This study does not observe the effect of using HCQ as a primary regimen to prevent cancer in RA patients. We are assured that HCQ is not associated with an increased risk of subsequent malignancy in RA patients. Further mechanistic research is needed.

Causal inference between rheumatoid arthritis and prostate cancer

It is unclear if the association between rheumatoid arthritis (RA) and a higher risk of prostate cancer (Pca) reflects a causal relationship. We conducted a meta-analysis and used the Mendelian randomization method (MR) to evaluate the association between RA and Pca risk. A meta-analysis and subgroup analysis of the incidence of Pca in patients with RA was conducted. To determine whether genetically elevated RA levels were causally linked to Pca, two MR samples were employed. To eliminate gender-related bias, we conducted a stratified analysis of the GWAS data for RA by gender, specifically including 140,254 males. Additional MR analysis was also performed to determine potential confounding factors influencing the association between genetically susceptible RA and Pca. In total, 409,950 participants were enrolled in 20 trials to investigate the Pca risk in patients with RA. The meta-analysis suggested that RA was unrelated to the Pca risk (SIR = 1.072, 95% CI, 0.883-1.261). However, a subgroup analysis showed that low smoking rates might increase the Pca risk in patients with RA by 24%. The MR analysis showed that increased genetic susceptibility to RA was related to a high Pca risk (OR = 36.20, 95%CI = 1.24-1053.12, P = 0.037). The causality estimation of MR-Egger, Weighted mode, Simple mode, and Weighted median method were similar in direction and magnitude. Although our meta-analysis found no correlation between RA and Pca risk, MR analyses supported a causal relationship between genetic susceptibility to RA and increased prostate risk. Early attention to Pca risk in patients with RA may be important for improving prognosis and mortality in such patients. Further research is needed to determine the etiology of RA attributed to Pca and its underlying mechanisms.

Potential Cancer Risk in Patients with Rheumatoid Arthritis: A Longitudinal Korean Population-Based Analysis

The potential link between rheumatoid arthritis (RA) and cancer incidence needs to be validated due to inconsistent results between Asian and Western countries. We explored the long-term association of RA with the overall and organ-specific cancer incidence using nationwide population data. This longitudinal follow-up study (2002–2015) included 3070 patients with RA and 12,280 controls (1:4 propensity score-matched for sex, age, residence, and income) from the Korean National Health Insurance Service-Health Screening Cohort database. A Cox proportional hazard model estimated the hazard ratio for malignancy following adjusting for covariates. Despite the similar overall cancer incidence between RA and control groups, differences in the incidence of organ-specific cancers were noted: the RA group had a 1.63-fold greater likelihood for lung cancer (95% confidence interval 1.11–2.40). In the sex-stratified subgroup analyses, the male RA patients exhibited higher odds of lung and thyroid cancer but a lower probability for colorectal cancer; no such associations were detected in either female patients with RA or age subgroups. In summary, the higher likelihood for lung cancer in Korean RA patients, especially thyroid and lung cancer in male RA patients, seems to be characteristic, which needs to be carefully monitored.