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M H Liang

Publications and source records attributed to M H Liang.

At least 19 recordsLinked to original sources
PubMed2003

Cost-effectiveness of low dose corticosteroids versus non-steroidal anti-inflammatory drugs and COX-2 specific inhibitors in the long-term treatment of rheumatoid arthritis.

OBJECTIVE: Non-steroidal anti-inflammatory drugs (NSAIDs) are used in nearly every patient with rheumatoid arthritis (RA) as part of a comprehensive management programme, but their use can be associated with side-effects. Low dose corticosteroid (<10 mg/day prednisone) in the treatment of RA is controversial. Although it is effective and possibly disease modifying, concerns exist about potential adverse events. We assessed costs and health effects of corticosteroids compared with NSAIDs and cyclo-oxgenase-2 (COX-2) inhibitors. METHODS: Markov (state transition) models were used to simulate a cohort of RA patients taking disease-modifying antirheumatic drugs and either corticosteroids or NSAIDs. The regimens were assumed to be equally effective for the control of RA. Data on incidence, costs and consequences of adverse events from corticosteroids and from NSAIDs were taken from the literature. Costs were measured in 1999 US dollars; health effects expressed as quality-adjusted life years (QALYs). Sensitivity analyses were performed including best-case scenarios (0.5x adverse event rate) and worst-case scenarios (1.5x adverse event rate). RESULTS: In the base-case analysis corticosteroids were superior to NSAIDs. The sensitivity analyses of adverse event rate, using best-case and worst-case scenarios, and age showed that the results were sensitive to each combination of adverse event rate and age. In contrast, the sensitivity analyses of costs and utilities were robust. Using misoprostol or omeprazole prophylaxis with NSAIDs would make corticosteroids cost-effective. Compared with NSAIDs with COX-2 specific inhibition, corticosteroids were still cost-effective. CONCLUSION: Corticosteroids are more cost-effective than NSAIDs and COX-2 inhibitors in the long-term treatment of RA.

Adult↗
PubMed2003

Validation of a Systemic Lupus Activity Questionnaire (SLAQ) for population studies.

The goal of this work was to develop an economical way of tracking disease activity for large groups of systemic lupus erythematosus (SLE) patients in clinical studies. A Systemic Lupus Activity Questionnaire (SLAQ) was developed to screen for possible disease activity using items from the Systemic Lupus Activity Measure (SLAM) and tested for its measurement properties. The SLAQ was completed by 93 SLE patients just prior to a scheduled visit. At the visit, a rheumatologist, blinded to SLAQ results, examined the subject and completed a SLAM. Associations among SLAQ, and SLAM (omitting laboratory items) and between individual items from each instrument were assessed with Pearson correlations. Correlations between pairs of instruments were compared using Student's t-tests. The mean score across all 24 SLAQ items was 11.5 (range 0-33); mean SLAM without labs was 3.0 (range 0-13). The SLAQ had a moderately high correlation with SLAM-nolab (r = 0.62, P < 0.0001). Correlations between patient-clinician matched pairs of items ranged from r = 0.06 to 0.71. Positive predictive values for the SLAQ ranged from 56 to 89% for detecting clinically significant disease activity. In studies of SLE, symptoms suggesting disease can be screened by self-report using the SLAQ and then verified by further evaluation.

Adult↗
PubMed2003

The ACR nomenclature for CNS lupus revisited.

Neuropsychiatric systemic lupus erythematosus (NPSLE) involves a wide range of peripheral and central nervous system manifestations. These manifestations are complex and their pathophysiology is poorly understood. NPSLE can precede the onset of lupus or occur at any time during its course. The American College of Rheumatology (ACR) developed a standardized nomenclature system providing case definitions for the neuropsychiatric syndromes of systemic lupus erythematosus (SLE) to facilitate and enhance patient classification and reporting requirements in clinical research. Estimates of NPSLE prevalence have ranged widely and most are based on research conducted before the introduction of ACR case definitions. This paper reviews the early experience with the ACR nomenclature use and possible future directions for its improvement. The identification and categorization of the major neuropsychiatric syndromes in SLE using ACR case definitions seems to be adequate, however the mildest and most subjective of the syndromes are the most problematic. Even if the definitions in their present form might have drawbacks the only way forward is further use of ACR nomenclature, pooling data from different populations, and collection of experience as a basis for improvement. The acquisition of normative data for ethnic, age and sex stratification would extend their usefulness.

Female↗
PubMed2001

Monoclonal gammopathy of undetermined significance and exposure to breast implants.

BACKGROUND: Animal studies and uncontrolled case series in humans have suggested a possible association between breast implant exposure and monoclonal gammopathy. OBJECTIVE: To assess whether there is an increased risk of monoclonal gammopathy in women with silicone breast implants, we conducted a retrospective study of women exposed to breast implants and matched nonexposed women nested within a prospective cohort study (the Nurses' Health Study). METHODS: We used serum protein electrophoresis and immunoglobulin subtype by immunofixation to test 288 women exposed to breast implants and 288 age-matched, nonexposed women who previously had provided a blood sample (1989-1990) for monoclonal proteins. RESULTS: Among the women exposed to breast implants, 5 had monoclonal gammopathy of undetermined significance (MGUS) compared with 4 women among those not exposed (odds ratio, 1.25; 95% confidence interval, 0.27-6.39). The distribution of isotypes was similar across exposure groups. The exposed women with MGUS tended to be older than the nonexposed women (mean age, 60.4 years vs 52.5 years, respectively; P =.03). None of the 9 women with MGUS had reported multiple myeloma or other hematologic malignancies up through 1996. CONCLUSIONS: We find little evidence to support a substantial increased risk of MGUS in women exposed to breast implants. Larger studies are needed to determine if a more modest relationship exists.

Age Factors↗
PubMed2001

The cost-effectiveness of vaccination against Lyme disease.

BACKGROUND: Vaccination against Lyme disease appears to be safe and effective; however, the cost per quality-adjusted life-year (QALY) gained with vaccination is unknown. METHODS: We developed a decision-analytic model to evaluate the cost-effectiveness of vaccination compared with no vaccination in individuals living in endemic areas of Lyme disease. Our analysis encompassed a 10-year time horizon including a 2-year vaccination schedule with an additional year of vaccine effectiveness. The costs and probabilities of vaccination risk, compliance and efficacy, and Lyme disease clinical sequelae and treatment were estimated from the literature. Health-related quality-of-life weights of the various clinical sequelae of Lyme disease infection were obtained from a sample of 105 residents from Nantucket Island, Massachusetts. RESULTS: Vaccinating 10 000 residents living in endemic areas with a probability of Lyme disease per season of 0.01 averted 202 cases of Lyme disease during a 10-year period. The additional cost per QALY gained compared with no vaccination was $62 300. Vaccination cost $12 600/QALY gained for endemic areas with an attack rate of 2.5% per season, and $145 200/QALY gained for an attack rate of 0.5%. Vaccinating individuals over an accelerated 2-month vaccination schedule improved the cost-effectiveness to $53 700/QALY gained. If a yearly booster shot is required for persisting efficacy, the marginal cost-effectiveness ratio increases to $72 700/QALY. The cost-effectiveness of vaccination was most sensitive to the Lyme disease treatment efficacy and assumptions about the persistence of vaccination effect. CONCLUSION: Vaccination against Lyme disease appears only to be economically attractive for individuals who have a seasonal probability of Borrelia burgdorferi infection of greater than 1%.

Cost-Benefit Analysis↗
PubMed2001

Lyme disease and preventive behaviors in residents of Nantucket Island, Massachusetts.

BACKGROUND: To determine the age-specific prevalence of Lyme disease and whether preventive behaviors on Nantucket Island correlate with Lyme disease, we surveyed island residents. METHODS: A survey with questions on Lyme disease symptoms, history, and preventive behaviors was mailed to all residents. Respondents were stratified by likelihood of having had Lyme disease. A subsample was selected for examination, and then classified according to the Lyme disease national surveillance case definition. RESULTS: The overall lifetime prevalence of Lyme disease for Nantucket residents was 15% (CI, 10%-19.8%): 19% among females, and 11% among males. The prevalence was highest among age groups 0-16 and 30-49 years. Overall, 86% of the population practiced at least one behavior. The most frequently reported preventive behavior was checking oneself for ticks (80%), followed by wearing protective clothing (53%), avoiding tick areas (34%), and using tick repellent (11%). Younger individuals practiced fewer preventive behaviors than older individuals (p=0.001). Although males reported greater tick exposure than females, females uniformly practiced preventive behaviors more frequently (p=0.001). The practice of preventive behaviors was not associated with a history of Lyme disease, but finding more than 5 ticks per year on oneself was (p=0.001). CONCLUSION: Lyme disease is highly prevalent on Nantucket Island. Young people are particularly at risk and health education should emphasize preventive behaviors less frequently practiced: using tick repellent, avoiding tick areas, and wearing protective clothing.

Adolescent↗
PubMed2001

Variable effects of social support by race, economic status, and disease activity in systemic lupus erythematosus.

OBJECTIVE: Health status and disease activity in patients with systemic lupus erythematosus (SLE) and other chronic diseases are strongly associated with social support, which suggests that enhanced social support in medical care might improve SLE outcome. There has been little or no study on identifying patients for whom social support would be most beneficial. It would allow practitioners to enable social support more effectively as a complement to disease management. METHODS: A retrospective cohort (200 patients with SLE from 5 centers), balanced by race and insurance status, was studied in a cross sectional design. Demographic, clinical, socioeconomic, and psychosocial factors and disease outcomes [Systemic Lupus Activity Measure (SLAM), Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR), SF-36] were measured. Using multivariate linear regression and ANOVA (outcome = SF-36 physical function, mental health), we examined the interaction between social support and patients' characteristics, including race, age, income, occupation, insurance, employment, education, and social network, and characteristics of the disease itself such as disease activity (SLAM) at diagnosis, damage (SLICC/ACR) at diagnosis, and comorbidity. RESULTS: In multivariate models, higher social support was significantly associated (p < 0.05) with better physical function when respondents were white, had income above poverty level, had Medicare or private insurance (vs Medicaid or no insurance), and had low disease activity at diagnosis. Social support was associated with better mental health, although there was no significant interaction between social support and other predictors of mental health. CONCLUSION: The data suggest that social support is beneficial for mental health for all groups, but has the greatest opportunity for influence among those already possessing social, economic, and health advantages.

Adult↗
PubMed2000

Coexposure to Borrelia burgdorferi and Babesia microti does not worsen the long-term outcome of lyme disease.

Previous studies suggest that concurrent Lyme disease and babesiosis produce a more sever illness than either disease alone. The majority of babesiosis infections, however, are subclinical. Our objective was to characterize on the basis of a total-population survey of Nantucket Island, Massachusetts, whether coexposure to Lyme disease and babesiosis causes more severe illness or poorer long-term outcomes than Lyme disease alone. In this retrospective cohort study, residents indicating a history of Lyme disease were compared with randomly selected population controls on a standardized medical history, blinded physical examination, and serological studies for Borrelia burgdorferi and Babesia microti. Serological evidence of exposure to babesiosis was not associated with increased severity of acute Lyme disease. The groups did not differ with regard to the prevalence of constitutional, musculoskeletal, or neurological symptoms a mean of 6 years after acute Lyme disease. Prior Lyme disease and serological exposure to B. microti are not associated with poorer long-term outcomes or more persistent symptoms Lyme disease alone.

Adult↗
PubMed2000

Long-term outcome of children surviving massive burns.

CONTEXT: Major advances in treatment of burn injuries in the last 20 years have made it possible to save the lives of children with massive burns, but whether their survival comes at the cost of impaired quality of life is unknown. OBJECTIVE: To investigate the long-term quality of life in children who have survived massive burns. DESIGN AND SETTING: Retrospective, cross-sectional study conducted in a regional pediatric burn center. PATIENTS: Eighty subjects who were younger than 18 years at the time of injury, who survived massive burns involving > or =70% of the body surface, and who were admitted to the burn center between 1969 and 1992 were evaluated an average (SD) of 14.7 (6.0) years after injury. MAIN OUTCOME MEASURES: Short Form 36 (SF-36) scores of the 60 patients aged at least 14 years were compared with national norms and the impact of clinical variables on individual domain scores was assessed. RESULTS: The SF-36 domain scores of the study patients, who had survived massive burns at a mean (SD) age of 8.8 (5.5) years, were generally similar to the normal population). However, 15% and 20% of the burn patients had scores in the physical functioning and physical role domains, respectively, that were more than 2 SDs below the relevant norm, indicating that a few patients had continuing serious physical disability. Better functional status of the family predicted a higher score in physical role (P = .04). The child's early reintegration with preburn activities predicted higher scores in general health (P = .03), physical functioning (P = .003), and physical role (P = .01). Children followed up consistently in the multidisciplinary burn clinic for 2 years had higher physical functioning (P = .04). CONCLUSIONS: In this study, while some children surviving severe burns had lingering physical disability, most had a satisfying quality of life. Comprehensive burn care that included experienced multidisciplinary aftercare played an important role in recovery.

Adult↗
PubMed2000

Association between clinical factors, socioeconomic status, and organ damage in recent onset systemic lupus erythematosus.

OBJECTIVE: To determine the prevalence and socioeconomic and clinical predictors of early organ damage in a cohort of patients with systemic lupus erythematosus (SLE) of 2-7 years' duration randomly sampled at 5 centers and balanced by socioeconomic status and race. METHODS: The Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR) Damage Index was measured in 200 patients who met the ACR criteria for SLE with a mean disease duration of 3.8 years. The SLICC/ACR scores for each organ system and the prevalence of damage within organ systems were assessed. Logistic regression analyses evaluated the simultaneous effects of age at diagnosis, disease duration, disease activity, and sociodemographic factors. RESULTS: Sixty-one percent of the patients had damage within 7 years of onset (mean 3.8 yrs). Neuropsychiatric (20.5%) and musculoskeletal (18.5%) systems were the most frequently involved, followed by renal (15.5%) and skin (12.5%) systems, all with median SLICC/ACR organ system scores of 1. In multivariate models, African-American race was associated with skin damage but not with damage in other specific organ systems. Socioeconomic status was not associated with organ system damage. Older age at diagnosis correlated with cardiovascular, musculoskeletal, gastrointestinal, ocular, and pulmonary damage. Clinical factors such as longer disease duration correlated with higher renal and cardiovascular damage, and greater disease activity at diagnosis of SLE correlated with greater renal, musculoskeletal, and pulmonary damage. CONCLUSION: There is evidence of organ system damage in SLE within a mean of 3.8 years after onset. We found little evidence for differences in early organ damage according to race or socioeconomic status. Damage to most organ systems was related to age at diagnosis of SLE and clinical factors such as disease duration.

Adult↗
PubMed2000

Do lupus disease activity measures detect clinically important change?

OBJECTIVE: New scales for the clinical assessment of patients with systemic lupus erythematosus (SLE) are valid and reliable, and quantitate disease activity. We assessed the responsiveness to change of 2 widely used standardized multi-item lupus activity measures, the revised Systemic Lupus Activity Measure (SLAM-R) and the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI), and their ability to detect clinically relevant changes. METHODS: Ninety-six (96) patients with definite SLE participated in this study. The group mean age was 45.0 (13.7) years, 91% were female, and the mean disease duration was 14.9 (7.5) years. Sociodemographic information, lupus activity (SLAM-R, SLEDAI), and damage were recorded at baseline. At each of the 5 monthly followup visits, the activity measures were repeated and a transition scale asked the physician if their patient's lupus activity had changed. Five different methods were used to compare the responsiveness of the activity measures studied: 1. the effect size; 2. the standardized response mean; 3. the control standardized response mean; 4. the area under the curve of a receiver operating characteristic (ROC) curve; and 5. a new multiple response modeling approach. RESULTS: Both SLAM-R and SLEDAI are responsive. SLAM-R is consistently, although moderately, more responsive than SLEDAI. All 5 methods of evaluating responsiveness yielded a consistent ranking of disease activity measures. CONCLUSION: SLAM-R and SLEDAI are responsive measures of lupus activity. SLAM-R appears to be more responsive than SLEDAI.

Activities of Daily Living↗
PubMed2000

Effect of low level lead exposure on hyperuricemia and gout among middle aged and elderly men: the normative aging study.

OBJECTIVE: To determine whether longterm lead accumulation is associated with hyperuricemia and gouty arthritis among middle aged and elderly men. METHODS: In a retrospective cohort study, 777 male participants were evaluated between August 1991 and October 1996 in the Department of Veterans Affairs Normative Aging Study, a 35 year longitudinal study of aging. We examined the development of gout and an increased uric acid level in relation to lead, adjusting for other known risk factors. Lead levels were measured in blood and by K x-ray fluorescence (K-XRF) technique in tibial (cortical) and patellar (trabecular) bone. RESULTS: Blood lead levels in this mostly Caucasian (97%) population were low (mean 5.9 microg/dl, SD 3.5). Bone lead levels were comparable to those described in other general populations. In a multivariate analysis adjusting for the risk factors, age, body mass index, diastolic blood pressure, alcohol intake, and serum creatinine level, there was a positive association between patellar bone lead and uric acid levels (p = 0.02). Of 777 participants, 52 (6.7%) had developed gouty arthritis. In logistic regression of similar covariates, body mass index (p < 0.0001) and serum creatinine level (p = 0.005) were the strongest determinants of gout; neither bone nor blood lead levels predicted gout in this cohort. CONCLUSION: The longterm accumulation of lead is associated with an increased uric acid level in middle aged and elderly men. However, this study shows no association between lead and gouty arthritis at the levels arising from community exposure.

Age Factors↗
PubMed2000

Longitudinal construct validity: establishment of clinical meaning in patient evaluative instruments.

OBJECTIVES: Although widely used and reported in research for the evaluation of groups, measures of health status and health-related quality of life have had little application in clinical practice for the assessment of individual patients. One of the principal barriers is the demonstration that these measures add clinically significant information to measures of function or symptoms alone. Here, we review the methods for evaluation of construct validity in longitudinal studies and make recommendations for nomenclature, reporting of study results, and future research agenda. METHODS: Analytical review. RESULTS: The terms "sensitivity" and "responsiveness" have been used interchangeably, and there are few studies that evaluate the extent to which health status or health-related quality-of life measures capture clinically important changes ("responsiveness"). Current methods of evaluating responsiveness are not standardized or evaluated. Approaches for the assessment of a clinically significant or meaningful change are described; rather than normative information, however, standardized transition questions are proposed. They would be reported routinely and as separate axes of description to capture individual perceptions. CONCLUSIONS: Research in methods to assess the subject's evaluation of the importance and magnitude of a measured change are critical if health status and health-related quality-of-life measures are to have an impact on patient care.

Health Services Research↗
PubMed2000

Hydroxychloroquine retinopathy despite regular ophthalmologic evaluation: a consecutive series.

We describe a consecutive series of patients with hydroxychloroquine (HCQ) retinopathy. Their clinical features illustrate that with normal renal function there is no threshold for total dosage for HCQ toxicity; that color vision testing is important; that almost all patients complain of altered central vision as their first symptom; and that a normal optic fundus does not exclude the diagnosis. Finally, HCQ retinopathy may progress even when the agent is stopped.

Aged↗
PubMed1999

Musculoskeletal and neurologic outcomes in patients with previously treated Lyme disease.

BACKGROUND: Previous follow-up studies of patients with Lyme disease suggest that disseminated infection may be associated with long-term neurologic and musculoskeletal morbidity. OBJECTIVE: To determine clinical and functional outcomes in persons who were treated for Lyme disease in the late 1980s. DESIGN: Population-based, retrospective cohort study. SETTING: Nantucket Island, Massachusetts. PARTICIPANTS: 186 persons who had a history of Lyme disease (case-patients) and 167 persons who did not (controls). MEASUREMENTS: Standardized medical history, physical examination, functional status measure (Medical Outcomes Study 36-item Short Form Health Survey [SF-36]), mood state assessment (Profile of Mood States), neurocognitive tests, and serologic examination. RESULTS: The prevalence of Lyme disease among adults on Nantucket Island was estimated to be 14.3% (95% CI, 9.3% to 19.1%). In multivariate analyses, persons with previous Lyme disease (mean time from infection to study evaluation, 6.0 years) had more joint pain (odds ratio for having joint pain in any joint, 2.1 [CI, 1.2 to 3.5]; P = 0.007), more symptoms of memory impairment (odds ratio for having any memory problem, 1.9 [CI, 1.1 to 3.5]; P = 0.003), and poorer functional status due to pain (odds ratio for 1 point on the SF-36 scale, 1.02 [CI, 1.01 to 1.03]; P < 0.001) than persons without previous Lyme disease. However, on physical examination, case-patients and controls did not differ in musculoskeletal abnormalities, neurologic abnormalities, or neurocognitive performance. Persons with previous Lyme disease who had persistent symptoms after receiving treatment (n = 67) were more likely than those who had completely recovered to have had fever, headache, photosensitivity, or neck stiffness during their acute illness (87% compared with 13%; odds ratio, 2.4 [CI, 1.0 to 5.5]; P = 0.045); however, the performance of the two groups on neurocognitive tests did not significantly differ. CONCLUSIONS: Because persons with previous Lyme disease exhibited no sequelae on physical examination and neurocognitive tests a mean of 6.0 years after infection, musculoskeletal and neurocognitive outcomes seem to be favorable. However, long-term impairment of functional status can occur.

Adult↗
PubMed1999

Outcomes of total hip and knee replacement: preoperative functional status predicts outcomes at six months after surgery.

OBJECTIVE: To determine whether patients with knee or hip osteoarthritis (OA) who have worse physical function preoperatively achieve a postoperative status that is similar to that of patients with better preoperative function. METHODS: This study surveyed an observational cohort of 379 consecutive patients with definite OA who were without other inflammatory joint diseases and were undergoing either total hip or knee replacement in a US (Boston) and a Canadian (Montreal) referral center. Questionnaires on health status (the Short Form 36 and Western Ontario and McMaster Universities Osteoarthritis Index) were administered preoperatively and at 3 and 6 months postoperatively. Physical function and pain due to OA were deemed the most significant outcomes to study. RESULTS: Two hundred twenty-two patients returned their questionnaires. Patients in the 2 centers were comparable in age, sex, time to surgery, and proportion of hip/knee surgery. The Boston group had more education, lower comorbidity, and more cemented knee prostheses. Patients undergoing hip or knee replacement in Montreal had lower preoperative physical function and more pain than their Boston counterparts. In patients with lower preoperative physical function, function and pain were not improved postoperatively to the level achieved by those with higher preoperative function. This was most striking in patients undergoing total knee replacement. CONCLUSION: Surgery performed later in the natural history of functional decline due to OA of the knee, and possibly of the hip, results in worse postoperative functional status.

Aged↗