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K Y Fong

Publications and source records attributed to K Y Fong.

At least 37 records · Page 2Linked to original sources
PubMed2000

Validation of a Chinese version of the Medical Outcomes Study Family and Marital Functioning Measures in patients with SLE.

The objective was to validate a Chinese translation of the Medical Outcomes Study Family and Marital Functioning Measures (FFM and MFM) in patients with systemic lupus erythematosus (SLE). Chinese-speaking SLE patients (n = 69) completed a self-administered questionnaire containing the FFM and MFM and assessing demographic and socio-economic status twice within a 2 week period. SLE activity, disease-related damage and quality of life were assessed using the BILAG, SLICC/ACR Damage Index and SF-36 Health Survey, respectively. Scale psychometric properties were assessed through factor analysis, Cronbach's alpha, quantifying test-retest differences and known-groups construct validity. Factor analysis identified 1 factor corresponding to the FFM and 2 factors corresponding to the MFM. Internal consistency for the FFM was excellent (alpha = 0.92) while that for the MFM was acceptable (alpha = 0.62). Mean (s.d.) test-retest differences were 0.06 (1.54) points for the FFM and 0.03 (2.08) points for the MFM. 11 and 10 of 13 a priori hypotheses relating the FFM and MFM, respectively, to demographic, disease and quality of life variables were confirmed, supporting the construct validity of these scales. The Chinese FFM and MFM are valid and reliable measures of family and marital functioning in Chinese-speaking SLE patients, with psychometric properties very similar to the source English version.

Adolescent↗
PubMed2000

Validation of the Chinese SF-36 for quality of life assessment in patients with systemic lupus erythematosus.

We studied the reliability and validity of the Chinese Short-Form 36 Health Survey (SF-36) in a cross sectional study of patients with systemic lupus erythematosus (SLE). Sixty-nine consecutive subjects completed a questionnaire containing the Chinese SF-36 twice within 14 d. Disease activity and damage were assessed using the British Isles Lupus Activity Group (BILAG) and SLICC/ACR Damage Index (DI) scales, respectively. Internal consistency was assessed using Cronbach's alpha, reliability using Spearman's correlation and repeatability coefficients, and relationships between SF-36, BILAG and DI scores using Spearman's correlation. The Chinese SF-36 showed high internal consistency (alpha = 0.72-0.91) and good reliability, with correlations exceeding 0.70 for 7 scales and mean scale score differences of < 2 points for 6 scales. SF-36 scores correlated weakly with BILAG scores (-0.27 to -0.41) and DI scores (-0.24 to -0.35), and subjects' mean SF-36 scores were 6-24 points lower than the general population, supporting construct validity of the SP-36. These data suggest that the Chinese SF-36 is a reliable and valid measure of quality of life in patients with SLE.

Adolescent↗
PubMed2000

Accuracy of medical record scoring of the SLICC/ACR damage index for systemic lupus erythematosus.

OBJECTIVE: To study the accuracy of medical record scoring of the SLICC/ACR Damage Index (DI) for SLE. METHODS: Medical record DI (MDI) scoring of 60 SLE patients by one physician was compared with prospective direct DI (DDI) scoring a median of 2 y earlier. Agreement between DDI and MDI total and organ system scores was compared using Cohen's kappa, the degree of misclassification by MDI and the significance of differences between DDI and MDI scores. RESULTS: The mean duration of SLE at DDI scoring was 5.2 y. The median/mean (SD) DDI and MDI total scores were 0/0.78 (1.38) and 0/0. 85 (1.44). Damage was present on DDI and MDI scoring in 36.7% (22/60) and 38.3% (23/60) of patients. Qualitative MDI and DDI total scores (damage present/absent) showed good agreement (kappa=0.61, 95% CI=0.40-0.82, 18.3% misclassification). Quantitative MDI and DDI total scores (degree of damage) showed moderate agreement (kappa=0. 47, 95% CI=0.28-0.66, 36.7% misclassification). 9 of 12 MDI organ system scores misclassified <10% of subjects. There was no statistically significant difference between DDI and MDI total or organ system scores. CONCLUSION: MDI total scoring is a good qualitative and moderate quantitative reflection of SLE related damage. MDI organ system scores are more accurate than MDI total scores.

Adolescent↗
PubMed2000

Central pontine myelinolysis--a rare manifestation of CNS Sjogren's syndrome.

Central nervous involvement in Sjogren's syndrome (CNS-SS) is not uncommon and has a variety of manifestations. We describe a 47-year-old woman with Sjogren's syndrome who presented with distal renal tubular acidosis with severe hypokalemia and hypokalemic myopathy. She developed progressive obtundation after years of stable disease. ANA, anti-Ro antibodies were positive. Brain MRI showed a cleft in the mid pons which was hypointense on T1 and hyperintense on T2 which was considered to be classical of central pontine myelinolysis. Serial MRI showed initial enlargement of the lesion which persisted despite successful immunosuppressive therapy with pulse methylprednisolone, pulse cyclophosphamide, plasmapheresis and IVIG.

Central Nervous System↗
PubMed2000

A prospective study of factors affecting quality of life in systemic lupus erythematosus.

OBJECTIVE: To prospectively identify factors influencing quality of life (QOL) over 6 months in patients with systemic lupus erythematosus (SLE). METHODS: Ninety ethnically diverse patients with SLE completed questionnaires administered 6 months apart assessing QOL (using the Medical Outcomes Study Short Form-36) and demographic, socioeconomic, psychosocial, and behavioral factors. Disease activity, damage, and treatment were recorded at both evaluations. Multiple linear regression (adjusting for baseline health status) was used to identify factors influencing mental and physical health. RESULTS: Improved physical health after 6 months was associated with reductions in learned helplessness (p = 0.034), improved mental health (p<0.001), longer disease duration (p = 0.009), and better physical health at baseline (p = 0.027). Improved mental health after 6 months was associated with better family support (p = 0.002), improvements in physical health (p<0.001), disease activity, and prednisolone dose (interaction term p = 0.019), less disease related damage (p<0.001), non-use of cytotoxic drugs (p = 0.02), and older age at diagnosis (p = 0.007). CONCLUSION: Potentially modifiable psychosocial, disease, and therapy related factors influence QOL in patients with SLE.

Adolescent↗
PubMed2000

The genetics of spondyloarthropathies.

INTRODUCTION: Spondyloarthropathies are a heterogeneous group of rheumatic disorders that commonly present with axial skeleton or sacroiliac joints involvement. Ocular involvement like uveitis, iritis and conjunctivitis can be present in up to a third of the patients. Genetic factors play a part in the pathogenesis of spondyloarthropathies. Association with the HLA-B27 gene, especially that between ankylosing spondylitis and HLA-B27 antigenic positivity, is one of the strongest association seen between a disease and a Class I antigen. This paper aims to review the frequencies of HLA-B27 gene and its subtypes in different population groups, possible mechanisms leading to the development of joint inflammation and the risk it confers for development of spondyloarthropathies. METHODS: The MEDLINE database was searched using keywords: HLA-B27, spondyloarthropathy, molecular mimicry, arthritogenic peptides, reactive arthritis and ankylosing arthritis. Related articles for selected papers were also consulted. Books on HLA-B27 and spondyloarthropathy were obtained through the NUS Medical Library's LINC system. RESULTS: The genetic subtypes and susceptibility to development of disease vary in different population groups. Other HLA genes and non-HLA genes also play a part in the development of spondyloarthropathies, especially in those who are HLA-B27 negative. HLA-B27-positive relatives of spondyloarthritics have a higher risk of developing a similar condition. The presence of the HLA-B27 gene may serve as an aid to diagnosis or prognosis for clinicians. In juvenile arthritic patients, it is a poor prognostic factor, predicting for disease severity. It is also associated with poor outcomes for patients with anterior uveitis. However screening of asymptomatic individuals for the HLA-B27 gene is not recommended. CONCLUSION: The polygenic nature of the disease needs further elucidation and study.

Arthritis↗
PubMed1999

Peripheral neuropathy in systemic lupus erythematosus.

The prevalence of clinically apparent peripheral neuropathy in systemic lupus erythematosus is reported to be between 2% to 18%. The purpose of this prospective case-control study was to determine the prevalence of peripheral neuropathy (PN) using electrodiagnostic criteria. Subgroup analysis was performed to determine whether PN correlated with disease activity, renal involvement, or serum immune markers. Fifty-four systemic lupus erythematosus patients and 30 controls were recruited in the study. The right median, ulnar, peroneal, tibial, and sural sensory and motor nerve conduction studies were obtained. PN in our study was defined as any abnormal values in motor and sensory distal latency, sensory action potential, motor action potential, or conduction velocity affecting 2 or more nerves. Of the 54 patients studied, PN was present in 15 patients (27.8%) of which 4 were symptomatic. There was a significant correlation between PN and anti-SM antibody, and there was a trend showing decreased motor and sensory action potential amplitudes in our systemic lupus erythematosus group compared to the controls. This observation was also seen in an active disease group when compared to those with inactive disease. The amplitude of the action potential was more often affected than the distal latency, and sensory nerves were more susceptible than motor nerves. The sural sensory action potential amplitude appears to be the most sensitive indicator of PN which may be used as an index to monitor disease activity.

Adolescent↗
PubMed1999

Validation of the medical outcomes study family and marital functioning measures in SLE patients in Singapore.

OBJECTIVE: To validate the Medical Outcomes Study Family and Marital Functioning Measures (FMM and MFM) in a multi-ethnic, urban Asian population in Singapore. METHODS: English speaking Chinese, Malay or Indian SLE patients (n=120) completed a self-administered questionnaire containing the FFM and MFM at baseline, after 2 weeks and after 6 months. Lupus activity, disease-related damage and quality of life were assessed using the British Isles Lupus Assessment Group (BILAG), Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR) Damage Index and SF-36 Health Survey respectively. Scale psychometric properties were assessed through factor analysis, Cronbach's alpha, quantifying test-retest differences and known-groups construct validity. RESULTS: Factor analysis of scores obtained at baseline and after 6 months identified 3 factors corresponding to the FFM (1 factor) and the MFM (2 factors). Both scales showed acceptable internal consistency, with Cronbach's alpha of 0.95 for the FFM and 0.70 for the MFM. Mean (s.d.) test-retest differences were -0.31 (3.82) points for the FFM and -0.70 (4.26) points for the MFM. Eleven out of 13 a priori hypotheses relating both the FFM and MFM to demographic, disease and quality of life variables were confirmed, supporting the construct validity of these scales. CONCLUSION: The FFM and MFM are valid and reliable measures of family and marital functioning in a multi-ethnic cohort of Asian SLE patients in Singapore.

Adolescent↗
PubMed1999

The Rheumatology Attitudes Index and its helplessness subscale are valid and reliable measures of learned helplessness in Asian patients with systemic lupus erythematosus.

OBJECTIVE: To assess the internal consistency, reliability, and construct validity of the Rheumatology Attitudes Index (RAI) and its subscales in a cohort of Asian patients with systemic lupus erythematosus (SLE). METHODS: English speaking ethnic Chinese, Malay, or Indian patients with SLE (n = 120) seen at a rheumatology unit completed a questionnaire containing the RAI twice within a 2 week period. Lupus activity was assessed using the British Isles Lupus Activity Group (BILAG) score, disease related damage using the Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR) damage index, and quality of life using the Medical Outcome Survey Short Form 36 Health Survey (SF-36). Factor analysis and Cronbach's alpha were used to study the psychometric properties of the RAI. The magnitude of test-retest differences was assessed using the method of Bland and Altman. Relationships between the RAI, its helplessness (HS) and internality (IS) subscales, and BILAG, SLICC/ACR damage index and SF-36 scores were studied using Spearman's rank correlation. RESULTS: Factor analysis (n = 105) identified 2 factors corresponding to the HS and IS subscales of the RAI. All scales showed acceptable internal consistency, with Cronbach's alpha of 0.64 for the HS, 0.77 for the IS, and 0.74 for the RAI. Mean (SD) test-retest differences were 0.85 (3.96) points for the HS (n = 86), 0.81 (4.44) points for the IS (n = 85), and 1.46 (7.88) points for the RAI (n = 74). Six of 10 hypotheses relating the RAI and HS to demographic, disease, and quality of life variables were confirmed, supporting the construct validity of these scales. CONCLUSION: The RAI and its helplessness subscale are valid and reliable measures of learned helplessness in a multiethnic cohort of Asian patients with SLE in Singapore.

Adolescent↗
PubMed1999

Validation of the MOS SF-36 for quality of life assessment of patients with systemic lupus erythematosus in Singapore.

OBJECTIVE: To assess the reliability and construct validity of the Medical Outcomes Study Short Form 36 Health Survey (SF-36) in a multiracial cohort of Asian patients with lupus in Singapore. METHODS: A cross sectional study was performed on 118 English speaking patients with lupus attending a specialist rheumatology unit between March and August 1996. Patients completed a questionnaire containing the UK standard version of the SF-36 twice within a 14 day period. All patients were assessed for disease activity using the British Isles Lupus Assessment Group score (BILAG), and for disease related damage using the Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR) damage index (DI). Relationships between SF-36, BILAG, and DI scores were studied using Spearman's rank correlation. Internal consistency of the SF-36 was assessed using Cronbach's alpha, and stability using the repeatability coefficient of Bland and Altman. RESULTS: SF-36 subscales showed high internal consistency, with Cronbach's alpha coefficient ranging from 0.84 to 0.94. Test-retest reliability was acceptable, with Spearman's rank correlation >0.70 for all subscales except role-physical, and mean differences in test scores of <2 points for 5 of 8 subscales. SF-36 subscale scores were weakly correlated with BILAG scores (Spearman's p -0.37 to 0.15) and SLICC/ACR DI scores (Spearman's p -0.25 to 0.23), suggesting divergent construct validity of the SF-36. CONCLUSION: These data suggest the SF-36 is a reliable and valid measure of the quality of life of patients with lupus in Singapore.

Cohort Studies↗
PubMed1998

Ophthalmic manifestations in Asian patients with systemic lupus erythematosus.

AIM OF STUDY: To determine the spectrum and prevalence of ophthalmic manifestations of systemic lupus erythematosus (SLE) in Asian patients. METHODS: We performed a standardised ophthalmic examination on consecutive Asian patients with SLE referred from a tertiary rheumatology unit to an ophthalmology department. RESULTS: Seventy patients were included in the study. There were 66 females (94%) and 4 males (6%). The mean (range) age of the patients was 32.9 (9-67) years. Five patients (7%) had ophthalmic symptoms while 65 (93%) were asymptomatic. Eighty-three eyes of 45 patients had abnormal Schirmer's #1 test and 27 of these eyes of 17 patients also had concomitant rose bengal staining of the cornea and/or conjunctiva. Seventeen eyes of 9 patients had retinal vascular lesions. Fourteen of these eyes had mild microangiopathic retinopathy with best-corrected visual acuity (BCVA) 6/12 or better and 3 had retinal vaso-occlusive disease with BCVA worse than 6/12. Twenty-eight eyes of 14 patients had cataract and 3 eyes of 2 patients had raised intraocular pressure. Twelve eyes of 7 patients had BCVA worse than 6/12 because of optic neuropathy (4 eyes), posterior subscapsular cataract (4 eyes), retinal vaso-occlusive disease (3 eyes) and phthisis bulbi (1 eye). None had any eyelid lesion, extraocular motility disorder or retrochiasmal disorder of vision. CONCLUSIONS: Asymptomatic dry eye is the most common ocular finding in patients with SLE. Sight-threatening complications of SLE include retinal vaso-occlusive disease and optic neuropathy.

Adolescent↗
PubMed1998

Clinical predictors of nephritis in systemic lupus erythematosus.

We identified clinical predictors of lupus nephritis presenting more than 6 months after the diagnosis of lupus in a cohort of 335 lupus patients. Almost 24% (80/335) of patients developed nephritis more than 6 months after the diagnosis of lupus. Using a Cox proportional hazards model, we found hypertension, thrombocytopaenia and leukopaenia to be associated with lupus nephritis presenting more than 6 months after diagnosis, with adjusted relative risks of 2.5 (95% CI 1.3 to 4.7), 4.3 (95% CI 1.7 to 10.8) and 3.2 (95% CI 1.7 to 6.2) respectively. In this cohort, hypertension, thrombocytopaenia and leukopaenia were associated with lupus nephritis presenting more than 6 months after the diagnosis of lupus.

Adult↗
PubMed1998

The sensitivity and specificity of autoantibodies to the Sm antigen in the diagnosis of systemic lupus erythematosus.

The anti-Sm test is thought to be specific for the diagnosis of systemic lupus erythematosus (SLE) and is one of the American College for Rheumatology (ACR) criteria for the classification of SLE. Locally, the sensitivity and specificity of this test for the diagnosis of SLE are unknown. We therefore aim to study the sensitivity and specificity of this test in our local context. A total of 1034 patient samples that were sent for routine testing of anti-Sm antibodies over a 30-month period, were included in the study. However, only 1031 patient samples were included in the final analysis as 3 casenotes were not traceable. Clinical diagnoses were obtained through a lupus database and chart review. Quantification of the anti-Sm antibodies was by the enzyme-linked immunosorbent assay (ELISA) technique. Positive anti-Sm test results were present in 165 samples, comprising 156 (94.5%) samples from lupus patients and 9 (5.5%) having diagnoses other than SLE. These diagnoses ranged from arthritis, overlap syndrome, Raynaud's phenomenon and cardiac-related diseases. The calculated sensitivity and specificity of the anti-Sm test, using a positive cut-off value of 20 units/ml, were 39.7% and 98.6%, respectively. If the positive cut-off value is raised to 30 units/ml, the specificity rises marginally to 99.5% but the sensitivity will drop by more than 10 percentage points to 27.2%. The anti-Sm test is not useful as a screening test for lupus but a positive result is highly specific for SLE.

Antigen-Antibody Reactions↗
PubMed1998

The genetics of systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is a disease characterised by diverse clinical manifestations and the presence of multiple autoantibodies. There are multiple aetiological factors involved in its pathogenesis. Genetic factors do play an important role and the major histocompatibility complex has been studied extensively and many human leukocyte antigen (HLA) associations have been reported. Twin and familial lupus studies confirm the importance of genetic factors in the development of SLE. Reported HLA associations range from that of HLA-DR3 in Caucasians to HLA-DR2 in Chinese, Japanese and American Blacks. These associations however may only represent linkage disequilibrium and not the actual susceptibility genes. Other non-major histocompatibility complex genes have also been reported to play important roles in the pathogenesis of lupus. The advent of molecular biological techniques has advanced the understanding of susceptibility genes in many diseases. The use of microsatellite genome scanning to study multiplex lupus families has yielded a wealth of information on clusters of susceptibility genes. The identification of these genes will be an important advance in the understanding of this complex disease.

Animals↗
PubMed1998

The effects of ethnicity on disease patterns in 472 Orientals with systemic lupus erythematosus.

OBJECTIVE: To determine the effects of ethnicity on disease manifestations in Oriental patients with systemic lupus erythematosus (SLE) and to describe the risk of developing renal or central nervous system (CNS) involvement with time. METHODS: A retrospective study of 472 patients with SLE seen at the only Rheumatology Unit in Singapore. The effect of ethnicity on selected disease manifestations at diagnosis was assessed after adjusting for demographic variables using multiple logistic regression. The probability of developing selected disease manifestations with time was determined using the Kaplan-Meier product limit method. RESULTS: At diagnosis, Malays had a higher risk of renal or CNS involvement than Chinese (OR 2.26, 95% CI 1.21 to 4.21, and OR 3.07, 95% CI 1.01 to 9.34, respectively), and Indians a lower risk of malar rash and a higher risk of oral ulcers than Chinese (OR 0.30, 95% CI 0.13 to 0.68, and OR 2.90, 95% CI 1.45 to 7.34, respectively). The prevalence of renal or CNS involvement in the entire cohort increased with time, reaching 75.6% (95% CI 66.1% to 85.0%) and 16.7% (95% CI 11.7% to 21.6%), respectively, after 18 years of disease. CONCLUSION: Ethnicity influenced disease manifestations at diagnosis in this cohort of Oriental patients with SLE. Renal or CNS involvement developed in previously unaffected patients up to 18 years after diagnosis, highlighting the need for continued vigilance in patients with lupus.

Adolescent↗