Potentials of additional copper filtration on radiation dose and image quality for adults underwent digital chest X-ray imaging in Dubai Health Authority - UAE

OBJECTIVE

To explore the potentials of adding copper (Cu) filter on image quality and patient dose of adult patients underwent chest X-ray examination METHODS: Patients were divided into four groups. Group 1, patients were exposed with no added Cu filter (standard or control), group 2 a 0.1 mm Cu filter was added, group 3 acquired with 0.2 mm Cu filter and group 4 performed with 0.3 mm Cu filter. Exposure index (EI), entrance surface dose (ESD) and dose area product (DAP) were recorded from the modality and retrospectively analyzed. The visual grading analysis score (VGAS) was used to evaluate image quality. Mann-Whitney T-Test and one-way ordinary ANOVA Test were used to evaluate statistical differences including gender-based findings.

RESULTS

EI, ESD and DAP data for a total of 784 patients (422 male and 362 female) that underwent indirect digital chest radiography exam were collected. Image quality was maintained when adding 0.1 mm Cu filter achieved with ∼19% DAP reduction. Female showed a significant DAP reduction comparing to male registered in the same group.

CONCLUSIONS

Reducing dose when using indirect digital chest radiography is possible with no trade-off on image quality. No loss of image quality was reported, images were broadly comparable.

IMPLICATIONS FOR PRACTICE

This study highlights the importance of utilizing the additional copper filter in digital chest radiography.

Cost-effectiveness of Denosumab for the Treatment of Postmenopausal Osteoporosis in Malaysia

From the perspective of Malaysian health care providers, denosumab was cost-effective in the treatment of postmenopausal osteoporosis, with an optimal outcome starting at age 60 years. Our results provide important insights into the value for money of anti-osteoporotic agents that can serve as a reference for other countries with comparable epidemiological data.

INTRODUCTION

The study aimed to compare the cost-effectiveness of denosumab with alendronate and no treatment in the management of postmenopausal osteoporosis among the Malaysian population.

METHODS

A well-validated Markov model was used to estimate the cost-effectiveness of denosumab in a hypothetical cohort of postmenopausal osteoporotic women between 50 and 80 years old who had no history of fractures. A 10-year time horizon from the perspective of Malaysian health care providers was used in this analysis. The model parameters, including transition probabilities and costs, were based on Malaysian sources. Treatment efficacy data were obtained from a network meta-analysis. The study outcomes were presented as incremental cost per quality-adjusted life-year (QALY) gained. Sensitivity analyses were performed to ensure the robustness of the results. A cost-effectiveness threshold was set at MYR 21,438 (USD 5175) per QALY.

RESULTS

Denosumab was found to be a cost-effective option for postmenopausal osteoporotic women aged 60 and older. The incremental cost-effectiveness ratios (ICERs) for denosumab versus alendronate ranged from MYR 16,955 (USD 4093) per QALY at age 60 to MYR 4380 (USD 1057) per QALY at age 80. The cost-effectiveness of denosumab improved monotonically with increasing age. Denosumab was 72.8-92.7% likely to be cost-effective at the cost-effectiveness threshold. Sensitivity analyses demonstrated that the results were robust across all parameter variations, with the annual cost of denosumab being the most sensitive.

CONCLUSIONS

From the perspective of the Malaysian health care provider, denosumab appears to be a cost-effective treatment choice for postmenopausal osteoporotic women over 60 years of age.

POS0394 VALIDATION OF THE SLE SUSCEPTIBLE GENE LOCI IN THE MULTI-ETHNIC MALAYSIAN SYSTEMIC LUPUS ERYTHEMATOSUS (SLE) COHORT AND THEIR ASSOCIATIONS WITH CLINICAL MANIFESTATION

Background

Systemic Lupus erythematous (SLE) is an autoimmune disease with a wide spectrum of clinical manifestations. Asian patients including Malaysia tend to have more severe disease with renal involvement. The differences could be due to the interactions between genetic and environmental factors. Thus, identifying the genetic associations from diverse populations provides a better understanding on the genetic architecture of this heterogeneous disease.

Objectives

The primary objective of this study was to validate the previously described SLE susceptibility gene loci among other population in the multi-ethnic Malaysian SLE patients. The secondary objective was to determine the association between the gene loci with organ-specific involvement across different Malaysian ethnicities.

Methods

This was a case-control study involving the recruitment of SLE patients who attended the outpatient clinic in Universiti Kebangsaan Malaysia Medical Centre (UKMMC) from July 2019 until March 2021. Their medical records were reviewed to record the socio-demographic characteristics and SLE clinical manifestations. The SLE susceptible gene loci from the NHGRI-EBI Catalog of human genome-wide association studies were reviewed. The gene loci with p values less than 5x10-8 tested in a total sample size of at least 1000 individuals were included in the genotyping study in our SLE patients. Healthy controls with frequency matching by gender and ethnicity-matched were also recruited in this study. Their peripheral blood samples were genotyped using the Agena MassARRAY system (Agena Bioscience). The genotype frequencies of susceptibility loci in all patients and controls were tested for Hardy–Weinberg equilibrium. Associations between phenotype and genotype were performed by logistic regression analysis.

Results

A total of 202 SLE patients and 206 healthy controls were recruited. The SLE cohort consisted of predominant Malay ethnicity (n=126,62.6%) followed by Malaysian Chinese (n=69, 34.2%) and Indian (n=7, 3.5%). After quality control and Hardy–Weinberg equilibrium test, a total of 27 candidate SNPs were genotyped in our study population. Meta-analysis revealed 5 gene loci at SNP rs4544377 (RNU6-546P), rs4917014 (IKZF1), rs1878186 (SLC12A1), rs4728142 (IRF5) and rs5029937 (TNFAIP3) were associated with SLE in Malaysian population (all p value <0.05). In Malay group, rs4544377 (RNU6-546P) and rs4728142 (IRF5) were found to be associated with SLE with adjusted OR 0.42 (95% CI: 0.24-0.74), p=0.002 and OR 3.08 (95% CI: 1.71-5.54), p=0.000169, respectively. In Malaysian Chinese group, rs4917014 (IKZF1) was found to be associated with SLE with OR 0.45 (95% CI: 0.23-0.86), p=0.016. Among Malay patients, rs1878186 (SLC12A1) was found to be associated with skin rash with OR 2.01 (95% CI: 1.20-3.35), p=0.008 while rs4544377 (RNU6-546P) and rs4917014 (IKZF1) were associated with lupus nephritis, with OR 0.48 (95% CI: 0.24-0.96), p=0.039 and OR 3.29 (95% CI: 1.18-9.20), p=0.023. In Malaysian Chinese patients, rs4544377 (RNU6-546P) was associated with muco-cutaneous manifestation with OR 2.82 (95% CI: 1.15-6.92), p=0.023 while rs4728142 (IRF5) was associated with haematological manifestation with OR 5.61 (95% CI: 1.69-18.60), p=0.005.

Conclusion

Our exploratory study demonstrates the associations of the established SLE genes in Malaysian SLE populations. There are variations in the SLE susceptible gene loci with clinical manifestations of SLE between Malay and Malaysian Chinese populations.

References

[1]J. E. Molineros, K. H. Chua, C. Sun, L. H. Lian, P. Motghare, X. Kim-Howard, et al. Evaluation of SLE Susceptibility Genes in Malaysians. Autoimmune Diseases 2014 Vol. 2014 Pages 305436

Acknowledgements

This study received funding from the Fundamental Research Grant Scheme (FRGS) of the Ministry of Education, Malaysia (FRGS/1/2018/SKK02/UKM/03/1)

Disclosure of Interests

None declared.

AB0302 FACTORS ASSOCIATED WITH GESTATIONAL DIABETES MELLITUS (GDM) IN A MULTI-ETHNIC SYSTEMIC LUPUS ERYTHEMATOSUS (SLE) COHORT

Background:

The risks of insulin resistance and diabetes mellitus are elevated in systemic lupus erythematosus (SLE) patients. The use of glucocorticoid and anti-double stranded DNA antibodies positive are among the factors reported to be associated with the risk of gestational diabetes mellitus (GDM) in SLE patients. However, the relationship between GDM in Asian SLE patients is still obscure.

Objectives:

To determine the prevalence of gestational diabetes mellitus (GDM) in a multi-ethnic SLE cohort in Malaysia and the associated risk factors.

Methods:

This was a retrospective study of SLE pregnant women who have completed their antenatal care in Universiti Kebangsaan Malaysia Medical Centre (UKMMC) from 2004 until 2019. Screening and diagnosis of gestational diabetes mellitus (GDM) were as recommended in the guidelines by the Ministry of Health Malaysia. Information on SLE disease activity and treatment at 6 months before pregnancy and during pregnancy were determined from the medical records. Univariate and multi-variable logistic regression analyses were performed to determine the factors associated with GDM in the SLE patients.

Results:

A total of 89 patients with 202 pregnancies were included in the study. Malay was the predominant ethnic in this cohort (n=82, 67.2%), followed by Chinese (n=33,27.0%) and Indian (n=7, 5.7%). The most common system involvement of SLE was musculoskeletal (n=91, 74.6%), followed by haematological (n=78, 63.9%), lupus nephritis (54.9%, n=67) and mucocutaneous (n=66, 54.1%). The prevalence of GDM was 8.9% (n=18). More patients with GDM had positive anti-cardiolipin IgG antibody (aCL IgG) and lupus anticoagulant (LA) antibody as compared to the patients with no GDM, (55.6% vs 25.8%, p=0.01) and (50.0% vs 25.4%, p=0.05) respectively. On the other hand, the use of hydroxychloroquine (HCQ) in pregnancy was significantly lower in GDM patients (11.1%) as compared to no GDM group (39.1%), p=0.02. There was no significant difference in the ethnicity, SLE system involvement, disease activity status and immunosupressant use including steroid, azathioprine and cyclosporine A at 6 months before and during pregnancy between the GDM and non-GDM group. A forward logistic regression which include aCL IgG, LA and HCQ use in pregnancy, only the HCQ use remained significantly associated with lower risk of GDM in the model with OR= 0.12, 95% C.I = 0.02-0.94, p=0.04.

Conclusion:

Our study demonstrates the potential benefit of hydroxychloroquine in reducing the risk of gestational diabetes mellitus in SLE patients. The prevalence of antiphospholipid antibodies particularly aCL IgG and LA was found to be higher among patients with GDM. Further prospective studies are needed to confirm this association.

References:

[1]Dong Y, Dai Z, Wang Z, et al. Risk of gestational diabetes mellitus in systemic lupus erythematosus pregnancy: a systematic review and meta-analysis. BMC Pregnancy and Childbirth. 2019 May;19(1):179. DOI: 10.1186/s12884-019-2329-0.

Disclosure of Interests:

None declared

OP0096 EXPOSURE TO DENGUE INFECTION DO NOT RAISE RISK OF RHEUMATOID ARTHRITIS: FINDINGS FROM THE MALAYSIAN EPIDEMIOLOGICAL INVESTIGATION OF RHEUMATOID ARTHRITIS (MYEIRA) CASE-CONTROL STUDY

Background:

Dengue infection is associated with joints pain mimicking disease onset symptom of rheumatoid arthritis (RA). However, there is lack of epidemiological studies on exposure to dengue infection and risk of future RA.

Objectives:

We investigated the relationship between exposure to dengue infection and risk of developing different subsets of RA, defined by the presence of anti-citrullinated peptide antibody (ACPA) in the multi-ethnic Malaysian population.

Methods:

Serum samples from 1,235 RA cases (i.e. 516 Malay, 254 Chinese, 405 Indians and 60 others/mixed-ethnicity) and 1,624 epidemiological matched population-based controls (i.e. 1,023 Malay, 208 Chinese, 297 Indians and 96 others/mixed-ethnicity) were assayed for presence of dengue IgG antibody using World Health Organization recommended ELISA kits. Positive results of dengue IgG antibodies indicates previous exposure to dengue infection(s). We performed chi-square and Mann-Whitney U analysis to determine the association of ever-exposed dengue infection with ACPA-positive/ACPA-negative RA and to investigate the antibody frequency and levels among the studied populations.

Results:

We observed high occurrence of dengue IgG antibody in the overall RA cases (79.7%) and matched controls (77.3%), with no significant differences detected between the ACPA subsets of RA. Ethnicity stratification analysis revealed a decrease risk of developing ACPA-positive RA in the Indian patients with positive dengue IgG antibody (OR=0.59, 95% CI=0.37-0.94, p=0.03), and in particular patients with elevated level of dengue IgG antibody (OR=0.44, 95% CI=0.25-0.78, p<0.05). On the other hand, the significant decrease mean levels of dengue IgG antibody were observed in the ACPA-positive RA subset for all three major ethnic groups (i.e. Malay, p<0.0001, Chinese, p<0.01 and Indian<0.05) (Figure 1). No association was observed between presence of dengue IgG antibody and ACPA-negative RA subset.

Figure 1.

Comparison of mean dengue IgG antibody level between ever-exposed dengue infection RA cases, stratified by ACPA status. Comparison of median dengue IgG antibody level between the ever-exposed dengue infection ACPA-positive RA and normal controls in the four ethnic groups. The red line indicates the mean level of dengue IgG antibody level

Conclusion:

Our findings demonstrated that exposure to dengue infection do not increase the risk of developing future RA in the multi-ethnic Malaysian population. The inverse associations observed in the Indian ethnic group are in line with the other studies investigating exposure to viral infection and risk of RA.

References:

[1]Sherina et al (2017) Low levels of antibodies against common viruses associate with anti-citrullinated protein antibody-positive rheumatoid arthritis; implications for disease aetiology. Arthritis Research & Therapy 2017, 19:2169

[2]Gissel García et. al. (2011) Long-term persistence of clinical symptoms in dengue-infected persons and its association with immunological disorders. International Journal of Infectious Diseases 15 (2011) e38–e43

Acknowledgements:

The authors would like to thank the Director General of Health, Ministry of Health Malaysia for supporting this study. The authors are also indebted to participants for their kind participation. This study was financially supported by the Ministry of Health, Malaysia (JPP-IMR 17-025) and the short-term research grant by UniKL RCMP (str16037).

Disclosure of Interests:

None declared

THU0283 DISTINCT CLINICAL FEATURES OF LATE–ONSET SYSTEMIC LUPUS ERYTHEMATOSUS AMONG MALAYSIAN MULTI-ETHNIC COHORT

Background:

Systemic Lupus Erythematosus (SLE) commonly affects young women in their reproductive age group. However, there is an increase prevalence of late-onset SLE, parallel to the higher life expectancies among general populations worldwide. It has been reported that up to 25% SLE populations have a later onset of disease and their disease expression and course may be different.

Objectives:

To determine the clinical features and outcomes of late-onset SLE patients in a multi-ethnic Malaysian cohort.

Methods:

Medical records of SLE patients who attended regular follow-up clinics in Universiti Kebangsaan Malaysia Medical Centre (UKMMC) from 2011 until June 2019 were reviewed. Late-onset SLE was defined as the onset of SLE symptoms or diagnosis after the age of 50 years old. Information on their socio-demographics and disease characteristics were obtained from the clinical records. Disease damage was assessed using the SLICC/ACR (Systemic Lupus International Collaborating Clinics/American College of Rheumatology) Damage Index (SDI) scores. The disease characteristics and autoantibody profiles were compared between late-onset and younger onset patients. Damage accrual at disease onset and at 5 years was obtained and compared between the two groups.

Results:

A total of 429 patients were included and majority of them were Malays (n= 225, 52.4%) followed by Chinese (n=180, 42), Indian (n=21, 4.9%) and others (n=3,0.7%). This multi-ethnic SLE cohort was consisted of predominantyly female patients (n=372,86.7%) with disease duration of 9.9 years ± 6.8 years. A total of 13.8% (n=59) had late onset SLE with mean onset of disease at 58.1 ± 6.3 years while younger group was 27.2 ± 9.4 years. The commonest system involvement among the late-onset group was haematological manifestation (69.5%).Compared to the younger-onset SLE, late-onset SLE occurred significantly higher among the Chinese (66.1%) as compared to Malay (32.3%), Indians and other ethnics (1.7%), p<0.01. Patients with late-onset SLE also had significantly less musculoskeletal (37.3% vs 62.4%) and renal (23.7% vs 71.1%), p<0.001 and tend to have less muco-cutanoues manifestations (28.8 vs 42.4%, p=0.06). Meanwhile, pulmonary involvement was more common among the late onset SLE patients (11.9% vs 0.8%, p<0.001). Extractable nuclear antigen (ENA) results were available in 197 patients and patients with late-onset SLE had significantly higher rate of anti-RO positive (63% vs 3.9%), p=0.01. Otherwise, no significant difference in the other autoantibodies expressions including anti-La, anti-Sm, anti-RNP, anti-ribosomal P and anti-phospholipid antibodies. Patients with late-onset SLE tend to have more damage accrual at 5 years as compared to the younger age group (p=0.07). The mortality in the late onset group was 13.6% (n=8) as compared to 2.7% (n=10) in the younger age group, p=0.01. Majority of the cause of death in the later onset SLE was infection (87.5%) while in the younger age group was infection and active disease (90%).

Conclusion:

Late onset SLE occurs more commonly among Chinese ethnics in Malaysia and Malaysian SLE patients with late onset of the disease have distinct clinical manifestations. Damage accrual at 5 years tend to be higher in the late-onset group and the mortality is significantly higher with the major cause of death is infection. The different disease expression and outcome in late onset SLE suggest different factors in influencing the disease course and hence further studies including their genetic profiles are warranted.

References:

[1]Paula I. Burgos; Graciela S. Alarcón. Late-onset Lupus: Facts and Fiction. Future Rheumatol. 2008;3(4):351-356.

[2]S Stefanidou, C Gerodimos, A Benos et al. Clinical expression and course in patients with late onset systemic lupus erythematosus. Hippokratia. 2013; 17(2): 153–156.

Acknowledgments:

This research was supported by the “Fundamental Research Grant Scheme (FRGS/1/2018/SKK02/UKM/03/1)” by Ministry of Education Malaysia

Disclosure of Interests:

Syahrul Sazliyana Shaharir: None declared, Mohd Shahrir Mohamed Said: None declared, Sakthiswary Rajalingham Speakers bureau: Pfizer (500USD), Hazlina Mahadzir: None declared, Ruslinda Mustafar: None declared, Asrul Abdul Wahab: None declared

Factors associated with increased white matter hyperintense lesion (WMHI) load in patients with systemic lupus erythematosus (SLE)

Introduction White matter hyperintense (WMHI) lesions are the most common finding in magnetic resonance imaging (MRI) of the brain in patients with systemic lupus erythematosus (SLE). Objective The objective of this article is to determine the clinical factors associated with an increase in WMHI lesion load among SLE patients. Method A total of 83 SLE patients with MRI of the brain from National University of Malaysia Medical Centre were included. The WMHI lesion load was determined using the Scheltens score and Fazekas scale, and their distribution was divided into the deep white matter (DWMHI) and periventricular (PVH) regions. The clinical correlates of WMHI lesions were initially determined using univariate analyses and subsequently multivariable regression analyses were performed to determine the independent factors of increased WMHI lesion load. Results MRI of the brain of 46 patients who had WMHI lesions were compared with 37 patients with normal MRI. We found significant association between the presence of WMHI lesions and age, presence of cerebral infarcts, positive antiphospholipid antibody (aPL), active disease, neuropsychiatric lupus (NPSLE) and disease damage. Age, SLEDAI scores, cerebral infarcts and disease damage were significantly associated with higher DWMHI and PVH Scheltens scores. Meanwhile, patients with active lupus nephritis (LN), lower serum albumin and more severe proteinuria were associated with larger Fazekas WMHI lesions. Multivariable regression analysis revealed that the independent factors associated with presence of WMHI lesions were positive aPL and SLEDAI scores ( p < 0.05). Higher WMHI Scheltens scores in both DWMHI and PVH were associated with presence of cerebral infarct but higher PVH lesion load was significantly associated with active SLE disease. Conclusion Presence of WMHI lesions in SLE was significantly associated with cerebral infarcts, aPL and high general SLE activity, suggesting both inflammation and ischaemia as the underlying pathology of these lesions.

Posterior reversible encephalopathy syndrome in systemic lupus erythematosus: pooled analysis of the literature reviews and report of six new cases

Introduction

Posterior reversible encephalopathy syndrome (PRES) is a rare neurological disorder which is increasingly recognized to occur in systemic lupus erythematosus (SLE).

Objective

The purpose of this study was to identify the characteristics of SLE patients with PRES and the associated factors of the poor outcome among them.

Methods

We investigated SLE patients who developed PRES between 2005–2011 at the Universiti Kebangsaan Malaysia Medical Centre. A comprehensive literature search was done to find all published cases of PRES in SLE. Pooled analysis was conducted to identify the factors associated with poor outcome.

Results

There were 103 cases of PRES in SLE published in the literature but only 87 cases were included in the analysis in view of incomplete individual data in the remaining cases. The majority of the cases were Asians (74.2%), female (95.4%) with mean age of 26.3 ± 8.8 years. PRES was highly associated with active disease (97.5%), hypertension (91.7%) and renal involvement (85.1%). We found that 79 patients had a full recovery (90.8%) with a mean onset of full clinical recovery in 5.6 ± 4.1 days. On univariate analysis and logistic regression analysis the predictors of poor outcome, defined as incomplete clinical recovery or death, were intracranial hemorrhage, odds ratio (OR) 14 (1.1–187.2), p = 0.04 and brainstem involvement in PRES, OR 10.9 (1.3–90.6), p = 0.003.

Conclusion

Intracranial hemorrhage and brainstem involvement were the two important predictors of poor outcome of PRES. Larger prospective studies are needed to further delineate the risk of poor outcome among them.

Predictors of thickened carotid intima media thickness among well controlled lupus nephritis patients in a Malaysian tertiary centre

OBJECTIVES

To investigate the prevalence of thickened carotid intima media thickness (CIMT) and its associated risk factors in patients with lupus nephritis (LN) who were in remission.

METHODS

This was a cross sectional study in which consecutive LN patients who were in remission and attending our Nephrology/SLE Clinic were included. Their demographic profile, traditional cardiovascular risk factors and treatment medications were evaluated by clinical interview and review of medical records. Carotid intima media thickness (CIMT) was measured using B Mode carotid ultrasonography. CIMT was considered to be abnormally thickened if it exceeded the 75th percentile matched for age-and sex-matched normal controls. The associated factors for thickened CIMT were examined.

RESULTS

A total of 39 patients with a mean remission duration of 29 ± 24.3 months and on a mean prednisolone dose of 9.10 ± 7.83 mg daily completed the study. Six patients (15.4%) had thickened CIMT. On univariate analysis, male gender, patient age, older age at diagnosis, higher serum CRP levels, greater proteinuria and higher mean cumulative azathioprine dose were associated with thickened CIMT (P<0.05). Lower mean cumulative doses of cyclosporine A (CyA) and mycophenolic acid (MPA) (P<0.05) each were associated with thickened CIMT. Using regression analysis, the associated factors of CIMT were older age at diagnosis and proteinuria.

CONCLUSIONS

Lupus factors particularly age at diagnosis and proteinuria were the associated factors of thickened CIMT. Larger prospective trials are indicated to confirm our findings.

Nocardiosis in a patient with rheumatoid arthritis treated with rituximab and a summary of reported cases

Rituximab is a B-cell-depleting monoclonal anti-CD20 antibody. It is widely used in haematology and rheumatology. However, usage of rituximab in immunosupressed patient has been associated with various opportunistic infections. The authors reported a case of refractory rheumatoid arthritis treated with rituximab, which later presented with non-resolving pneumonia with pulmonary nodule. Percutaneous computer tomogram guided lung biopsy was arranged to confirm the suspicion of tuberculosis, but did not yield conclusive results. Later, she presented left-chest abscess and underwent incision and drainage. The pus culture and sensitivity confirmed pulmonary nocardiosis with chest wall dissemination. She was treated with 2-week course of trimethoprim sulfamethoxazole and responded. The authors also reviewed published cases of nocardiosis post-rituximab.

In-vitro expression of adhesion molecules and bone specific markers are depending on the cell culture material

Bone formation is an active process whereby osteoblasts are found on the surface of the newly formed bone. Adhesion to extracellular matrix is essential for the development of bone however not all surfaces are suitable for osteoblast adhesion and don't support osteoblastic functions. The objective of this study was to test the suitability of a collagen based microcarrier which would support osteoblastic functions.