Epidemiology and risk factors associated with avascular necrosis in patients with autoimmune diseases: a nationwide study

Trends in avascular necrosis and related arthroplasties in hospitalized patients with systemic lupus erythematosus and rheumatoid arthritis

OBJECTIVE

Avascular necrosis (AVN) is a devastating complication often necessitating arthroplasty, particularly common in systemic lupus erythematosus (SLE). Limited research exists on arthroplasty trends since new steroid-sparing agents. We analyzed trends and characteristics associated with AVN and AVN-related arthroplasties among SLE and RA hospitalizations using two decades of data from the U.S. National Inpatient Sample (NIS).

METHODS

This cross-sectional study used NIS (2000-2019) to identify hospitalized adults with SLE and RA, with or without AVN, using ICD codes. AVN was further grouped by arthroplasty status. Primary outcomes were AVN and AVN-related arthroplasty rates and time trends in SLE and RA. Baseline sociodemographics and comorbidities were compared. Analyses used STATA and Joinpoint regression to calculate annual percent change (APC).

RESULTS

Overall, 42,728 (1.3 %) SLE and 43,600 (0.5 %) RA hospitalizations had concomitant AVN (SLE-AVN and RA-AVN). Of these, 16,724 (39 %) and 25,210 (58 %) underwent arthroplasties, respectively. RA-AVN increased (APC: 0.98*), with a decrease in arthroplasties (APC: -0.82*). In contrast, SLE-AVN initially increased with a breakpoint in 2011 (APC 2000-2011: 1.94* APC 2011-2019 -2.03), with declining arthroplasties (APC -2.03*). AVN hospitalizations consisted of individuals who were younger and of Black race; while arthroplasties were less likely in individuals of Black race or Medicaid coverage.

CONCLUSION

We report a breakpoint in rising SLE-AVN after 2011, which may relate to newer steroid-sparing therapies (i.e., belimumab). AVN-associated arthroplasties decreased in SLE and RA. Fewer AVN-associated arthroplasties were noted for Black patients and those with Medicaid, indicating potential disparities. Further research should examine treatment differences impacting AVN and arthroplasty rates.

Effect of Corticosteroid Use on the Occurrence and Progression of Osteonecrosis of the Femoral Head: A nationwide Nested Case-Control Study

BACKGROUND

Although it is very well known that corticosteroids cause osteonecrosis of the femoral head (ONFH), it is unclear as to which patients develop ONFH. Additionally, there are no studies on the association between corticosteroid use and femoral head collapse in ONFH patients. We aimed to investigate the association between corticosteroid use and the risk of ONFH among the general population and what factors affect ONFH occurrence. Additionally, we aimed to demonstrate which factors affect femoral head collapse and total hip arthroplasty (THA) after ONFH occurrence.

METHODS

A nationwide, nested case-control study was conducted with data from the National Health Insurance Service Physical Health Examination Cohort (2002 to 2019) in the Republic of Korea. We defined ONFH (N = 3,500) using diagnosis and treatment codes. Patients who had ONFH were matched 1:5 to form a control group based on the variables of birth year, sex, and follow-up duration. Additionally, in patients who have ONFH, we looked for risk factors for progression to THA.

RESULTS

Compared with the control group, ONFH patients had a low household income and had more diabetes, hypertension, dyslipidemia, and heavy alcohol use (drinking more than 3 to 7 drinks per week). Systemic corticosteroid use (≥ 1,800 mg) was significantly associated with an increased risk of ONFH incidence. However, lipid profiles, corticosteroid prescription, and cumulative doses of corticosteroid did not affect the progression to THA.

CONCLUSION

The ONFH risk increased rapidly when cumulative prednisolone use was ≥ 1,800 mg. However, oral or high-dose intravenous corticosteroid use and cumulative dose did not affect the prognosis of ONFH. Since the occurrence and prognosis of ONFH are complex and multifactorial processes, further study is needed.

Osteonecrosis in patients with inflammatory bowel disease: a systematic review and meta-analysis

BACKGROUND

The relationship of inflammatory bowel disease (IBD) with osteonecrosis or avascular necrosis (AVN) is uncertain.

METHODS

Systematic review to estimate the frequency of osteonecrosis in IBD was performed. Electronic databases were searched on 12 December 2022 to identify relevant studies. We planned to estimate the pooled prevalence of AVN in IBD, the risk in IBD when compared to the healthy population (without any chronic disease), and the impact of steroid use on osteonecrosis (IBD with and without steroid use). The risk of Bias was assessed with the Joanna Briggs Institute appraisal tool.

RESULTS

Fifteen studies including 105 154 individuals were included. The pooled rate AVN was 10.39 per 1000 patients (95% confidence interval, 4.44-24.11, I 2  = 97%). Subgroup analysis suggested that the prevalence was lower in larger studies (>1000 participants) at 3.10, 1.07; 8.98, I 2  = 98% versus 21.03, 8.69; 50.01, I 2  = 83%. The use of steroids did not seem to increase the risk of osteonecrosis in the included studies (pooled odds ratio: 1.88, 0.55-6.41, I 2  = 39%). The systematic review was limited by the absence of comparison with the control population free of chronic disease.

CONCLUSION

IBD may be associated with a risk of osteonecrosis. Future studies should assess the risk in comparison to the healthy population and the impact of disease activity and IBD therapies on the risk.

The Role of Osteogenic Effect and Vascular Function in Bone Health in Hypertensive Rats: A Study of Anti-hypertensive and Hemorheologic Drugs

Vascular dysfunction contributes to the development of osteopenia in hypertensive patients, as decreased blood supply to bones results in tissue damage and dysfunction. The effect of anti-hypertensive medicines on bone mass in hypertensive individuals is inconclusive because of the varied mechanism of their action, and suggests that reducing blood pressure (BP) alone is insufficient to enhance bone mass in hypertension. Pentoxifylline (PTX), a hemorheological drug, improves blood flow by reducing blood viscosity and angiogenesis, also has an osteogenic effect. We hypothesized that improving vascular function is critical to increasing bone mass in hypertension. To test this, we screened various anti-hypertensive drugs for their in vitro osteogenic effect, from which timolol and hydralazine were selected. In adult female spontaneously hypertensive rats (SHRs), timolol and hydralazine did not improve vascular function and bone mass, but PTX improved both. In female SHR animals, PTX restored bone mass, strength and mineralization, up to the level of normotensive control rats. In addition, we observed lower blood vasculature in the femur of adult SHR animals, and PTX restored them. PTX also restored the bone vascular and angiogenesis parameters that had been impaired in OVX SHR compared to sham SHR. This study demonstrates the importance of vascular function in addition to increased bone mass for improving bone health as achieved by PTX without affecting BP, and suggests a promising treatment option for osteoporosis in hypertensive patients, particularly at-risk postmenopausal women.

The Utility of Ultrasound in Evaluating Joint Pain in Systemic Lupus Erythematosus: Looking beyond Fibromyalgia

BACKGROUND

Systemic lupus erythematosus (SLE) is a complex autoimmune condition with varied clinical presentations, and musculoskeletal pain is one of the most commonly associated symptoms. However, fibromyalgia (FM) is a prevalent co-existing condition in SLE patients that can also cause widespread pain, and in patients with both conditions, it is often difficult to distinguish the underlying cause of musculoskeletal pain and provide optimal therapy.

METHODS

A retrospective cohort study was conducted including all adult SLE patients who received musculoskeletal ultrasound (US) examinations for joint pain at the Ohio State University Wexner Medical Center between 1 July 2012, and 30 June 2022. Binary and multiple logistic regression analyses were performed to determine predictors of US-detected inflammatory arthritis as well as improved musculoskeletal pain.

RESULTS

A total of 31 of 72 SLE patients (43.1%) had a co-existing diagnosis of FM. In binary logistic regression, a co-existing diagnosis of FM was not significantly associated with US-detected inflammatory arthritis. In multiple logistic regression analysis, clinically detected synovitis was significantly associated with US-detected inflammatory arthritis (aOR, 142.35, p < 0.01), and there was also a weak association with erythrocyte sedimentation rate (ESR) (aOR 1.04, p = 0.05). In separate multiple logistic regression analysis, US-guided intra-articular steroid injection was the only predictor of improved joint pain at follow-up visit (aOR 18.43, p < 0.001).

CONCLUSIONS

Musculoskeletal US can be an effective modality to detect inflammatory arthritis as well as to guide targeted intra-articular steroid injection to alleviate joint pain in SLE patients with or without FM.