Changes in bone mineral density over 10 years in patients with early rheumatoid arthritis

Exploring the Causal Relationship Between Osteoporosis and Rheumatoid Arthritis: A Bidirectional Mendelian Randomization Study

Objective

Osteoporosis and rheumatoid arthritis (RA) are commonly associated, but whether there is a causal genetic relationship between them remains unclear. This study used a two-sample Mendelian randomization (MR) approach to investigate this causal relationship.

Methods

Genetic instruments for osteoporosis and RA were obtained from published genome-wide association studies (GWAS). We selected SNPs with genome-wide significance (p < 5×10-8) and independent variation (r2 < 0.001). Causality was assessed using the inverse variance weighted (IVW) method, and heterogeneity, pleiotropy, and robustness were tested using Cochran's Q test, MR-Egger intercept, and leave-one-out sensitivity analysis.

Results

The MR analysis revealed a causal effect of decreased bone mineral density (BMD) on RA risk (TB-BMD: OR = 1.094, 95% CI = 1.023-1.170, P = 0.009; FA-BMD: OR = 1.159, 95% CI = 1.019-1.320, P = 0.025; LS-BMD: OR: 1.175, 95% CI = 1.070-1.291, P = 0.001). Osteoporosis at different sites and age groups significantly influenced RA, while RA did not significantly affect osteoporosis. Sensitivity analyses confirmed the robustness of the results.

Conclusion

Our study suggests a potential causal relationship between osteoporosis and RA, suggesting that osteoporosis may predispose individuals to RA. Further research is needed to understand the mechanisms and to confirm these findings across diverse populations.

Risk and predictors of fractures in early rheumatoid arthritis - A long term follow up study of an inception cohort

OBJECTIVES

To examine the risk of fractures in a cohort of patients with newly diagnosed rheumatoid arthritis (RA), compared to the background population, and predictors of fractures detectable early in RA.

METHODS

An inception cohort of patients with RA (N = 233; 164 women/69 men, recruited 1995-2005) was evaluated according to a structured program, including repeated clinical assessments and measures of bone mineral density (BMD), from diagnosis to 10 years later. Matched population controls were identified using the national census register. Fractures through 2019 were identified based on ICD codes. Cox regression models were used to assess the risk of fractures in RA patients compared with controls, and for assessment of potential predictors for fractures in the RA population.

RESULTS

RA patients had an increased risk of fractures (fully adjusted hazard ratio (HR) 1.52, 95 % CI 1.13; 2.06). In the RA cohort, high age, low body mass index, and low BMD were significant baseline predictors of future fractures in multivariate analyses, but baseline RA disease characteristics were not. Worse disability (i.e. higher Health Assessment Questionnaire (HAQ) scores) over time was significantly associated with increased risk of fractures (age-sex-adjusted HR 1.33 per SD, 95 % CI 1.09; 1.63) and there was an inverse association between BMD Z-scores over time and fractures.

CONCLUSION

Patients with RA had higher risk of fractures than controls. Fracture risk was related to BMD at baseline and over time in patients with RA. In addition, worse disability (measured by HAQ) over time was associated with higher risk of fractures.

Significant decrease of osteoporosis and osteoporotic fractures in rheumatoid arthritis within a period of 24 years: experiences of a single centre

OBJECTIVES

Rheumatoid arthritis (RA) is associated with an increased risk for osteoporosis and osteoporotic fractures. Since the treatment of RA has improved significantly in recent years, we can expect RA-associated osteoporosis to decrease with good disease control. Therefore, we conducted a retrospective study to investigate whether the frequency of osteoporosis and osteoporotic fractures has changed during 24 years in RA.

METHODS

We analysed the data of 1.086 RA patients from the time of the first osteological assessment with bone mineral density (BMD) measurement and collection of osteologically important data during the years 1996 and 2019 at our clinic. According to the treatment period, the patients were divided into cohort 1 (investigation between 1996 and 2004; n=539) and cohort 2 (investigation between 2005 and 2019; n=547). The data of the two cohorts were compared, and predictors of BMD were analysed by linear regression analysis.

RESULTS

Prevalence of osteoporosis (28.3% vs 48.4%; p<0.001) as well as osteoporotic peripheral fractures (11.5% vs 21%; p<0.001) and vertebral fractures (6.6% vs 10.9%; p=0.011) were significantly lower and treatment with biologicals (19.7% vs 5.0%; p<0.001) significantly more common and glucocorticoid use was significantly less common (p=0.005) in cohort 2. In RA patients with a disease duration of more than 2 years, BMD was significantly higher under treatment with biologicals (p<0.001) despite increased cumulative glucocorticoid dosages (p<0.001).

CONCLUSION

Our study showed a significant decline in osteoporosis and osteoporotic fractures in RA for 24 years. This positive effect is associated with the more frequent use of biologicals in the years between 2005 and 2019.

Potential association of rheumatic diseases with bone mineral density and fractures: a bi-directional mendelian randomization study

BACKGROUND

Previous studies have implicated rheumatoid arthritis as an independent risk factor for bone density loss. However, whether there is a causal relationship between rheumatic diseases and bone mineral density (BMD) and fractures is still controversial. We employed a bidirectional Mendelian analysis to explore the causal relationship between rheumatic diseases and BMD or fractures.

METHODS

The rheumatic diseases instrumental variables (IVs) were obtained from a large Genome-wide association study (GWAS) meta-analysis dataset of European descent. Analyses were performed for the three rheumatic diseases: ankylosing spondylitis (AS) (n = 22,647 cases, 99,962 single nucleotide polymorphisms [SNPs]), rheumatoid arthritis (RA) (n = 58,284 cases, 13,108,512 SNPs), and systemic lupus erythematosus (SLE) (n = 14,267 cases, 7,071,163 SNPs). Two-sample Mendelian randomization (MR) analyses were carried out by using R language TwoSampleMR version 0.5.7. The inverse-variance weighted (IVW), MR-Egger, and weighted median methods were used to analyze the causal relationship between rheumatic diseases and BMD or fracture.

RESULTS

The MR results revealed that there was absence of evidence for causal effect of AS on BMD or fracture. However, there is a positive causal relationship of RA with fracture of femur (95% CI = 1.0001 to 1.077, p = 0.046), and RA and fracture of forearm (95% CI = 1.015 to 1.064, p = 0.001). SLE had positive causal links for fracture of forearm (95% CI = 1.004 to 1.051, p = 0.020). Additionally, increasing in heel bone mineral density (Heel-BMD) and total bone mineral density (Total-BMD) can lead to a reduced risk of AS without heterogeneity or pleiotropic effects. The results were stable and reliable. There was absence of evidence for causal effect of fracture on RA (95% CI = 0.929 to 1.106, p = 0.759), and fracture on SLE (95% CI = 0.793 to 1.589, p = 0.516).

CONCLUSIONS

RA and SLE are risk factors for fractures. On the other hand, BMD increasing can reduce risk of AS. Our results indicate that rheumatic diseases may lead to an increased risk of fractures, while increased BMD may lead to a reduced risk of rheumatic diseases. These findings provide insight into the risk of BMD and AS, identifying a potential predictor of AS risk as a reduction in BMD.

Osteoporosis-related fractures in men and women with established and early rheumatoid arthritis: predictors and risk compared with the general population

OBJECTIVES

To study the risk of osteoporosis-related fractures in a community-based sample of men and women with rheumatoid arthritis (RA) overall, as well as early (< 1 year of disease duration, follow-up time maximum 10 years) and established (RA diagnosis since ≥ 5 years on July 1, 1997) RA, compared with the general population. To study potential risk factors for fractures in patients with RA from baseline questionnaire data.

METHODS

A community-based cohort of patients with RA (n = 1928) was studied and compared to matched general population controls. Information on osteoporosis-related fractures (hip, proximal upper arm, distal forearm and vertebral fractures) during the period July 1, 1997 to December 31, 2017 was obtained by linkage to the Swedish National Inpatient Register and the Cause of Death Register. The incidence of fractures was estimated in patients and controls. Cox regression models were used to assess the relation between RA and the risk of fractures and to assess potential predictors of fractures in RA patients. Analyses were stratified by sex, and performed in all patients with RA, and in subsets with early and established RA.

RESULTS

The overall incidence of osteoporosis-related fractures in the RA cohort was 10.6 per 1000 person-years (95% CI 9.31; 12.0). There was an increased risk of fractures overall in both men (hazard ratio (HR) 1.55, 95% CI 1.03; 2.34) and women (HR 1.52; 95% CI 1.27; 1.83) with RA compared to controls, with significantly increased risk also in the hip. No increased risk of osteoporosis-related fractures overall was seen in patients with early RA (HR 1.01, 95% CI 0.69; 1.49). Higher age, longer duration of RA, higher HAQ scores and higher scores in the visual analogue scale for global health were predictors of fractures.

CONCLUSION

Both men and women with RA were at increased risk of osteoporosis-related fractures. Patients with early RA did not have significantly increased risk during the first 10 years of disease in this study.

Osteoporosis epidemiology using international cohorts

PURPOSE OF REVIEW

To provide an update on the most important new cohort studies within osteoporosis and their bearing on clinical management and directions for future research.

RECENT FINDINGS

We identified a collection of new observational cohort studies - including new reports from already established large cohorts - and intervention studies providing new insights into osteoporosis pathophysiology, risk finding, intervention, and treatment barriers.

SUMMARY

Recent cohort studies in osteoporosis highlight the importance of timely identification and treatment of people who are at high risk of suffering osteoporotic fractures. Physical performance is a strong indicator of fracture risk and one that is tightly linked to a number of chronic conditions, not least inflammatory conditions like rheumatoid arthritis. Advances in case finding may involve opportunistic screening for low bone mineral density and vertebral fractures of radiology images obtained for other purposes, polygenic risk scores, and routinely collected medication and comorbidity information.

Low cumulative disease activity is associated with higher bone mineral density in a majority Latinx and Asian US rheumatoid arthritis cohort

OBJECTIVE

Prior studies have found conflicting results when evaluating the association between rheumatoid arthritis (RA) disease activity and bone mineral density (BMD). Whether or not cumulative RA disease activity is associated with BMD remains unanswered.

METHODS

Data were from the University of California San Francisco RA Cohort from years 2006-2018. Those with BMD measures and at least two study visits prior to BMD measure were included in the study. The association between low cumulative disease activity, as measured by DAS28ESR, with the primary outcome of femoral neck BMD was assessed using multivariable linear regression. Sensitivity analyses were performed substituting CDAI for the disease activity measure as well as total hip and lumbar spine BMD as outcomes.

RESULTS

161 participants with RA were studied. The cohort was 62.4 ± 10.2 years old and 88% female. Hispanic/Latino (N = 73, 45%) and Asian (N = 59, 37%) were the most common racial/ethnic groups in our cohort. Mean RA duration was 10.5 ± 7.3 years and 83% were ACPA positive. Low disease activity was independently associated with higher femoral neck BMD compared to the moderate/high disease activity group (β= 0.071 [95%CI: 0.021 to 0.122], p = 0.020). The relationship between low cumulative disease activity was similar when CDAI and other BMD sites were substituted in the multivariable models.

CONCLUSION

Low cumulative disease activity as measured by DAS28ESR was associated with higher femoral neck BMD, independent of traditional osteoporosis risk factors (e.g., age, sex, BMI) in a unique RA cohort. Results were similar when evaluating cumulative low CDAI and other BMD sites.

Anti-Inflammatory Effects of Low-Dose Glucocorticoids Compensate for Their Detrimental Effects on Bone Mineral Density in Patients with Rheumatoid Arthritis

Objectives: This study aimed to provide reliable information on the impact of low-dose glucocorticoids (GCs) on the bone mineral density (BMD) of patients with rheumatoid arthritis (RA). Methods: This retrospective study enrolled 933 patients with RA who continued the consumption of GCs (GC group) and 100 patients who had discontinued consumption for >1 year (no-GC group). The BMD values were measured at baseline and follow-up, and the annual rate of change in BMD between the groups was compared using dual-energy X-ray absorptiometry. We used multiple linear regression analysis to identify the factors associated with changes in BMD. Results: The demographic characteristics and use of medical treatments affecting bone metabolism were similar between the two groups. Furthermore, there were no significant differences in the annual rate of changes in BMD and incidence of newly developed osteoporosis and incidental fractures between the two groups. Multiple linear regression analysis revealed that the disease activity score for 28 joints with erythrocyte sedimentation rate was the only factor affecting the annual rate of changes in BMD, and it was inversely proportional to changes in BMD. Conclusion: The benefits of GC therapy in attenuating inflammation compensate for the risk of osteoporosis if adequate measures to prevent bone loss are implemented in patients with RA.

Association Between Bone Mineral Density and Autoantibodies in Patients With Rheumatoid Arthritis

Objective

Autoantibodies, such as anti–citrullinated protein antibodies (ACPAs), have been described as inducing bone loss in rheumatoid arthritis (RA), which can also be reflected by bone mineral density (BMD). We therefore examined the association between osteoporosis and autoantibodies in two independent RA cohorts.

Methods

Dual x‐ray absorptiometry (DXA) of the lumbar spine and left hip was performed in 408 Dutch patients with early RA during 5 years of follow‐up and in 198 Swedish patients with early RA during 10 years of follow‐up. The longitudinal effect of ACPAs and other autoantibodies on several BMD measures was assessed using generalized estimating equations.

Results

In the Dutch cohort, significantly lower BMD at baseline was observed in ACPA‐positive patients compared to ACPA‐negative patients, with an estimated marginal mean BMD in the left hip of 0.92 g/cm² (95% confidence interval [95% CI] 0.91–0.93) versus 0.95 g/cm² (95% CI 0.93–0.97) (P = 0.01). In line with this, significantly lower Z scores at baseline were noted in the ACPA‐positive group compared to the ACPA‐negative group (estimated marginal mean Z score in the left hip of 0.18 [95% CI 0.08–0.29] versus 0.48 [95% CI 0.33–0.63]) (P < 0.01). However, despite clear differences at baseline, ACPA positivity was not associated with greater decrease in absolute BMD or Z scores over time. Furthermore, there was no association between BMD and higher levels of ACPAs or other autoantibodies (rheumatoid factor and anti–carbamylated protein antibodies). In the Swedish cohort, ACPA‐positive patients tended to have a higher prevalence of osteopenia at baseline (P = 0.04), but again, ACPA positivity was not associated with an increased prevalence of osteopenia or osteoporosis over time.

Conclusion

The presence of ACPAs is associated with significantly lower BMD at baseline, but not with greater BMD loss over time in treated RA patients. These results suggest that ACPAs alone do not appear to contribute to bone loss after disease onset when disease activity is well‐managed.

Is there an association between rheumatoid arthritis and bone changes in the temporomandibular joint diagnosed by cone-beam computed tomography? A systematic review and meta-analysis

OBJECTIVES

Evaluate the relation of rheumatoid arthritis (RA) and bone changes in the temporomandibular joint diagnosed by cone-beam computed tomography (CBCT).

MATERIALS AND METHODS

This systematic review and meta-analysis were recorded in the PROSPERO database, using the CRD42020153246 protocol. The electronic searches were performed in the following databases: Pubmed, Scopus, Web of Science, Lilacs, Cochrane, and Open Grey. Cross-sectional studies that evaluated patients with RA with bone changes in the temporomandibular joint diagnosed by CBCT, without language restriction or publication date, were included. Meta-analysis was performed in Stata Software (StataCorp, TX, USA, version 12.0), using the metan, and a random effects model, and the risk of different bone alterations occurring in adults with and without arthritis was estimated using odds ratios (ORs) as a pooled measure of effect. Forest plots were used to present the isolated and the pooled effects (ORs and 95% CI).

RESULTS

Six studies were used for qualitative synthesis and 2 studies for quantitative synthesis. All studies diagnosed higher prevalence changes in the bone structures of the TMJ of RA patients, described as erosion, flattening, sclerosis, and osteophytes. Meta-analysis showed that the chance of bone changes occurring in components of the TMJ is greater in individuals who have RA.

CONCLUSION

There is an association between RA and bone changes in TMJ structures diagnosed through CBCT, as RA patients were more likely to have osteoarthritic changes in this joint.

CLINICAL RELEVANCE

Understanding the existence of an association between bone alterations in TMJ and RA can assist in the management of patients.

Time-averaged disease activity of rheumatoid arthritis associated with long-term bone mineral density changes

Background:

Rheumatoid arthritis (RA) is associated with poor bone mineral density (BMD). We designed the current study owing to the lack of long-term prospective studies regarding whether a high disease activity leads to increased bone loss.

Methods:

We have continually enrolled patients with RA. According to the average disease activity score in 28 joints based on the erythrocyte sedimentation rate (DAS28-ESR) during follow-up, the patients were classified into remission, low disease activity, and moderate or high disease activity groups. Patients were examined with dual-energy X-ray absorptiometry at baseline and after 3 years of follow-up. BMD changes were compared among the groups.

Results:

We have studied 477 patients. Overall BMD was significantly reduced from baseline to the 3-year follow-up (p < 0.05). After stratifying according to the time-averaged DAS28-ESR levels and use of anti-osteoporosis treatment (AOT), the BMD values of the femur and spine significantly increased in patients in the remission group with AOT. The BMD changes of different DAS28-ESR patients were further compared using the generalized estimation equation model. For the patients on AOT, the negative change in femoral BMD values of the moderate or high activity group was significant when compared with the remission group with positive BMD changes (regression coefficient, –0.038; 95% confidence interval, –0.055 to –0.021).

Conclusion:

For RA patients, if remission is achieved, AOT can better improve BMD, especially in the femur. In addition, moderate or high disease activity will lead to significant bone loss; therefore, disease activity must be actively controlled.