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Kenneth K C Lee

Publications and source records attributed to Kenneth K C Lee.

13 recordsLinked to original sources
PubMed2007

Calcium absorption in postmenopausal Chinese women: a randomized crossover intervention study.

The Ca intake and food sources of Chinese postmenopausal women are quite different from those of their Western counterparts. But, little information on Ca metabolism is available in Chinese populations. We determined true fractional calcium absorption (TFCA), true Ca absorption(= TFCA x Ca intake, Va), urinary Ca excretion (Vu,) and the difference between Va and Vu, (Va-u), in response to three dietary Ca intake levels. Twenty-one healthy postmenopausal Chinese women aged 49-64 years were recruited for this randomized crossover trial from a general community, Guangzhou, China. Subjects were randomly assigned to receive 0, 500 and 1000 mg Ca/d for 5 weeks separated by 2-week washout periods. TFCA using Ca stable isotopes, total urinary Ca excretion and Ca intake were determined after 4 weeks of adaptation. Mean values for total Ca intake (Vi) of the three phases were 391 (SD 197), 880 (SD 130) and 1382 (SD 160) mg/d. On usual diet, TFCA, Vu, Va, and Va-u were 0.57 (SD 0.12), 175 (SD 59) mg/d, 216 (SD 98) mg/d and 41 (SD 99) mg/d, respectively. With the supplementations of 500 and 1000 mg Ca/d, TFCAsignificantly decreased to 0.52 (SD 0.12) and 0.43 (SD 0.13) (P<0.001); whereas urinary Ca (P=0.003), Va and Va-u increased significantly (P< 0.001). Using a mixed-effects nonlinear regression model, it was estimated that Va-u was approaching a plateau when mean Ca intake reached 1300 mg/d. In conclusion, the present findings suggest postmenopausal Chinese women have high Ca absorption efficiency and a mean Ca intake of about 1300 mg/d is required to maximize the Va-u.

Biomarkers↗
PubMed2006

A cost analysis in patients with acute coronary syndrome using clopidogrel in addition to aspirin in a Hong Kong public hospital.

Results from the Clopidogrel in Unstable Angina to Prevent Recurrent Events (CURE) study showed that clopidogrel plus aspirin, compared to aspirin alone, reduced cardiovascular events (death, myocardial infarction, and stroke) in patients with acute coronary syndromes (ACS). Yet the acquisition cost of clopidogrel is much higher. It would therefore be worthwhile to compare the long-term cost impact of these 2 regimens. Until recently, only very few patients with ACS received clopidogrel-aspirin combination therapy in Hong Kong. Therefore, a hypothetical cohort was formed and compared to a real group of patients treated with aspirin alone. For the aspirin group, medical history was reviewed and cardiovascular and gastrointestinal events occurring in a period of 12 months after initiation of therapy were recorded. The target cost items included hospitalisation, emergency room visits, outpatient clinic visits, related medications, diagnostic tests, procedures, and surgery. For the hypothetical cohort, the probabilities/relative risks for clinical events were adopted from the CURE study. Fifty-four consecutive patients with ACS receiving aspirin therapy were identified and studied between January 1, 2001 and December 31, 2001 from a major public hospital in Hong Kong. The average cost of management per patient over the 12 month period for the aspirin group was HK$85,324 (US$10,940, HK$7.8 = 1 US$) versus the hypothetical cohort HK$83,903 (US$10,757). Hospitalisation represented the major cost item (64.6%), followed by the cost of investigational tests (14.5%) and procedural cost (11.6%). According to our analytical model, the overall cost impact between clopidogrel plus aspirin versus aspirin alone in the 2 groups of patients was similar.

Aged↗
PubMed2006

Interventions of hospital pharmacists in improving drug therapy in children: a systematic literature review.

Medicines' management or pharmaceutical care in paediatric patients is particularly demanding, mainly because the majority of available drugs have been developed for use in adults. As a result, in children, drugs are often unlicensed or used off-label, suitable formulations or appropriate strengths are lacking, and drugs have to be extemporaneously prepared, liquids and injections diluted, and tablets split. These factors increase the likelihood of medication errors and may lead to a reduction in drug effect. Age-specific changes in pharmacokinetics and pharmacodynamics further complicate drug therapy in children. All these challenges provide unique opportunities for pharmacists to improve the quality of care for paediatric patients. We conducted a systematic literature review examining whether the interventions of hospital pharmacists improve drug therapy in children. Several medical and pharmaceutical databases were searched systematically to identify articles investigating hospital pharmacists' interventions that were intended to improve drug therapy in children. Inclusion criteria were English language, primary research papers and studies in which clinical pharmacists contributed directly to patient care. Exclusion criteria were reviews, editorials, questionnaire studies, modelling studies, letters and studies only available in abstract form. This systematic search identified 18 articles documenting the role of a clinical hospital pharmacist in paediatric care. These articles were divided into the following groups based on study type: (i) studies documenting interventions made by pharmacists and their role in inpatients; (ii) articles presenting the outcomes of a satellite pharmacy; and (iii) articles examining pharmacist involvement in paediatric outpatient clinics. No randomised study comparing pharmacist interventions with standard care was found. In conclusion, although it was difficult to compare the various studies identified because of the different settings, design, duration, size, methodology and definition, all these studies highlighted the importance of hospital pharmacists to medicines' management in paediatric patients. On the basis of this review, we can conclude that pharmacist reviewing of medication charts is very important in identifying medication errors; hence, it is likely to be the most effective method of improving drug therapy in children.

Adverse Drug Reaction Reporting Systems↗
PubMed2006

Corticosteroids are not present in a traditional Chinese medicine formulation for atopic dermatitis in children.

INTRODUCTION: Traditional Chinese medicine (TCM) has been used as an alternative in treating children with atopic dermatitis (AD) but its efficacy and potential side effects are debatable. We recently used a TCM capsule (PentaHerbs) on 9 children and observed significant reductions in clinical scores of disease severity. However, there have been concerns that the therapeutic effects of many forms of TCM are due to the presence of corticosteroids. The purpose of this study was to evaluate if common corticosteroids are present in PentaHerbs capsules. MATERIALS AND METHODS: PentaHerbs powder was analysed with thin-layer chromatography, infra-red spectrophotometry and liquid chromatography mass spectrometry. RESULTS: Hydrocortisone, prednisolone, fludrocortisone and dexamethasone were not detected in the PentaHerbs capsules. CONCLUSION: Corticosteroids are not present in the 5 familiar herbs that were earlier shown to have efficacy on AD.

Child↗
PubMed2005

Clopidogrel versus aspirin and esomeprazole to prevent recurrent ulcer bleeding.

BACKGROUND: Concurrent therapy with a proton-pump inhibitor is a standard treatment for patients receiving aspirin who are at risk for ulcer. Current U.S. guidelines also recommend clopidrogel for patients who have major gastrointestinal intolerance of aspirin. We compared clopidogrel with aspirin plus esomeprazole for the prevention of recurrent bleeding from ulcers in high-risk patients. METHODS: We studied patients who took aspirin to prevent vascular diseases and who presented with ulcer bleeding. After the ulcers had healed, we randomly assigned patients who were negative for Helicobacter pylori to receive either 75 mg of clopidogrel daily plus esomeprazole placebo twice daily or 80 mg of aspirin daily plus 20 mg of esomeprazole twice daily for 12 months. The end point was recurrent ulcer bleeding. RESULTS: We enrolled 320 patients (161 patients assigned to receive clopidogrel and 159 to receive aspirin plus esomeprazole). Recurrent ulcer bleeding occurred in 13 patients receiving clopidogrel and 1 receiving aspirin plus esomeprazole. The cumulative incidence of recurrent bleeding during the 12-month period was 8.6 percent (95 percent confidence interval, 4.1 to 13.1 percent) among patients who received clopidogrel and 0.7 percent (95 percent confidence interval, 0 to 2.0 percent) among those who received aspirin plus esomeprazole (difference, 7.9 percentage points; 95 percent confidence interval for the difference, 3.4 to 12.4; P=0.001). CONCLUSIONS: Among patients with a history of aspirin-induced ulcer bleeding whose ulcers had healed before they received the study treatment, aspirin plus esomeprazole was superior to clopidogrel in the prevention of recurrent ulcer bleeding. Our finding does not support the current recommendation that patients with major gastrointestinal intolerance of aspirin be given clopidogrel.

Aged↗
PubMed2005

Factors affecting the maintenance stable warfarin dosage in Hong Kong Chinese patients.

BACKGROUND: Multiple factors can affect the anticoagulation effect of warfarin. The objective of this study was to determine the relationship between different clinical factors and outcomes of warfarin therapy in Hong Kong Chinese patients. METHODS: The study was conducted at the anticoagulation clinic of the Prince of Wales Hospital from 1 April to 31 December 2003. Clinical data collected included demographics, indications of warfarin, dietary vitamin K consumption, and drug-drug interactions. Blood samples were obtained for the genetic polymorphism analysis of CYP 2 C 9. Linear and multiple regression analysis were used for statistical analysis to determine the correlation between variables and the importance of various factors as the determinants of warfarin dosage requirement. RESULTS: A total of 63 patients were recruited. The mean warfarin dosage was 3.30+/-2.23 mg/day. The warfarin dosage ranged from 0.75 to 12 mg/day. The mean age was 59+/-14 years old. Age, dietary vitamin K consumption, chronic heart failure, atrial fibrillation, hypertension, smoking and drinking status were found to be factors statistically significant affecting warfarin dosage. We detected no single nucleotide polymorphism in CYP 2 C 9 exon 4. CONCLUSION: Age, dietary vitamin K consumption, warfarin indication for atrial fibrillation, co-morbid with CHF, smoking and drinking status were found to be the factors that affected the warfarin requirement in Hong Kong Chinese patients. However, the genetic polymorphism in exon 4 of CYP 2 C 9 may not be associated with the warfarin sensitivity in this patient population.

Adult↗
PubMed2005

Effects of vitamins C and E on oxidative stress markers and endothelial function in patients with systemic lupus erythematosus: a double blind, placebo controlled pilot study.

OBJECTIVE: Patients with systemic lupus erythematosus (SLE) experience excess morbidity and mortality due to coronary artery disease (CAD) that cannot be fully explained by the classical CAD risk factors. Among emerging CAD risk factors, oxidative stress is currently being emphasized. We evaluated the effects of longterm antioxidant vitamins on markers of oxidative stress and antioxidant defense and endothelial function in 39 patients with SLE. METHODS: Patients were randomized to receive either placebo or vitamins (500 mg vitamin C and 800 IU vitamin E daily) for 12 weeks. Markers of oxidative stress included malondialdehyde (MDA) and allantoin. Antioxidants measured included erythrocyte superoxide dismutase and glutathione peroxidase, plasma total antioxidant power (as FRAP value), and ascorbic acid and vitamin E concentrations. Endothelial function was assessed by flow-mediated dilatation (FMD) of the brachial artery and plasma concentration of von Willebrand factor (vWF) and plasminogen activator inhibitor type 1 (PAI-1). Primary outcome of the study included the change in lipid peroxidation as revealed by MDA levels. Secondary outcomes included changes in allantoin and antioxidant levels and change in endothelial function. RESULTS: After treatment, plasma ascorbic acid and alpha-tocopherol concentrations were significantly (p < 0.05) increased only in the vitamin-treated group, associated with a significant decrease (p < 0.05) in plasma MDA. Other oxidative stress markers and antioxidant levels remained unchanged in both groups. FMD and vWF and PAI-1 levels remained unchanged in both groups. CONCLUSION: Combined administration of vitamins C and E was associated with decreased lipid peroxidation, but did not affect endothelial function in patients with SLE after 3 months of therapy.

Allantoin↗
PubMed2003

Cost-effectiveness analysis of high-dose omeprazole infusion as adjuvant therapy to endoscopic treatment of bleeding peptic ulcer.

BACKGROUND: Intravenous administration of proton pump inhibitors after endoscopic treatment of bleeding peptic ulcers has been shown to decrease the rate of recurrent bleeding and the need for subsequent surgery. Yet there is a relative lack of formal assessment of this practice. The aim of this study was to examine the cost-effectiveness of this therapy by using standard pharmacoeconomic methods. METHODS: The present study was performed in conjunction with a randomized controlled clinical trial that included 232 patients who received either omeprazole (80 mg intravenous bolus followed by infusion at 8 mg/hour for 72 hours) or placebo after hemostasis was achieved endoscopically. A cost-effectiveness analysis was performed to evaluate the different outcomes of the trial. All related direct medical costs were identified from patient records. Cost-effectiveness ratios were calculated. RESULTS: Analysis by the Kolmogorov-Smirnov test showed that the direct medical cost in the omeprazole group was lower than that for the placebo group. Cost-effectiveness ratios for omeprazole and placebo groups were, respectively, HK$ 28,764 (US$ 3688) and HK$ 36,992 (US$ 4743) in averting one episode of recurrent bleeding in one patient after initial hemostasis was achieved endoscopically. CONCLUSIONS: Intravenous administration of high-dose omeprazole appears to be a cost-effective therapy in reducing the recurrence of bleeding and need for surgery in patients with active bleeding ulcer after initial hemostasis is obtained endoscopically.

Adult↗
PubMed2003

Relationship between patients' warfarin knowledge and anticoagulation control.

OBJECTIVE: To evaluate patients' knowledge of warfarin and its relationship to anticoagulation control. METHODS: From January to March 1999, 122 patients attending the warfarin clinic of the Prince of Wales Hospital in Hong Kong were interviewed. Their knowledge of warfarin therapy and adherence to medical advice were tested by 9 questions. A score (maximum 1.0) was calculated for each patient. The number of international normalized ratios (INRs) that was within the target range in the 4 most recent clinic visits was noted. RESULTS: Fifty-six men and 66 women participated in the study (mean +/- SD age 58.0 +/- 13.0, duration of treatment 43.1 +/- 39.8 mo). Patients' warfarin knowledge was poor, with an overall score of 0.48 +/- 0.18. Participants generally knew the colors of their warfarin tablets and took them regularly. They almost always informed their physicians and dentists of their warfarin therapy. Only 40-45% of patients knew the strengths of their warfarin tablets, the reason for taking warfarin, and its effect on the body. Their deficiencies in knowledge were even more obvious with respect to the possible consequences of under- or over-anticoagulation, drugs and medicated oils that might interact with warfarin, and management of a missed dose. Knowledge was related to age (r -0.43; p < 0.001) and duration of therapy (r 0.18; p = 0.044). Sixty patients (49.2%) had read the information booklet on warfarin and had better knowledge than those who had not (0.53 +/- 0.20 vs. 0.42 +/- 0.20; p < 0.001). Illiteracy was the main reason for not reading the booklet. There was a positive correlation between patients' warfarin knowledge and the number of INR values that was within the target range in the 4 most recent clinic visits (r 0.20; p = 0.024). CONCLUSIONS: Patients' warfarin knowledge, a determinant of anticoagulation control, was generally poor. More attention should be given to the education of elderly and illiterate patients.

Adult↗
PubMedDate not supplied

A cost comparison of management of chronic hepatitis B and its associated complications in Hong Kong and Singapore.

GOALS: To estimate and compare the direct medical cost in the management of chronic hepatitis B (CHB) infection and its complications from the perspective of public health organizations in Hong Kong and Singapore. BACKGROUND: Hong Kong and Singapore are endemic hepatitis B virus areas with about 10% and 5%, respectively, of the population estimated as hepatitis B virus infected. STUDY: The medical histories of 660 patients with CHB who received medical services over 5 years from three major public hospitals in Hong Kong and Singapore were studied retrospectively. Costs were analyzed according to the five disease states and estimated in Hong Kong dollars (HKD) and Singapore dollars (SGD). RESULTS: In both Hong Kong and Singapore, the per-patient total annual cost increased with the severity of the disease. CHB cost HKD 6318 (US 810 dollars) in Hong Kong and SGD 718.15 (US 410.37 dollars) in Singapore. Compensated cirrhosis cost HKD 10,304 (US 1321 dollars) in Hong Kong and SGD 1,175.34 (US 671.62 dollars) in Singapore. Decompensated cirrhosis cost HKD 58,428 (US 7490 dollars) in Hong Kong and SGD 15,389.84 (US 8794.19 dollars) in Singapore. Hepatocellular carcinoma cost HKD 121,822 (US 15,618 dollars) in Hong Kong and SGD 12314.04 (US 7036.59 dollars) in Singapore. Each case of liver transplant was estimated to cost HKD 514,498 (US 65,961 dollars) in Hong Kong and SGD 86,369.28 (US 49,353.87 dollars) in Singapore. CHB in Hong Kong accounted for about 4% of the healthcare expenditure. CONCLUSION: This study confirms that CHB and its liver disease complications are a significant economic burden to the healthcare budgets of Hong Kong and Singapore, and indicates that effective therapy that arrests or reverses the progression of liver disease would be highly cost-effective.

Adolescent↗
PubMedDate not supplied

What is next for pharmacoeconomics and outcomes research in Asia?

OBJECTIVES: Pharmacoeconomics and outcomes research have the potential for rapid adoption in the Asia Pacific region. Nevertheless, the region is characterized by great diversity in social and economic development, ethnicity, population size, health-care system, culture, language, and religion. Thus, the rate of adoption is also quite diverse across the region. METHODS: Among the countries reviewed in this article, governments take varying levels of interest in applying this research in health policy decisions. For example, some countries have already implemented systems that require pharmacoeconomic studies as one component of a new pharmaceutical product's approval for reimbursement, whereas others recommend such data but do not require it in policy and medical decision making. The literature in the countries reviewed is actually quite robust given the early stages of development of this field in most countries. The academic community has members trained in this field of research in all the countries reviewed and some universities have established departments whereas others have just introduced a few classes in the area. RESULTS: At the moment, pharmacoeconomics and outcomes research are being conducted mainly by academics. In addition, some pharmaceutical researchers are active and pharmaceutical companies are currently preparing to conduct more of this research as part of their strategy for Asian drug development. CONCLUSIONS: Prospects for future growth and development in this field are quite good in Asia as rapid healthcare inflation, increasing rates of chronic conditions and aging population, and increasing technology diffusion will underpin the need for greater awareness of the need to incorporate economic efficiency into the health-care systems.

Aged↗