Real-world evidence of improved healthcare utilization in patients with schizophrenia or schizoaffective disorder after early treatment of paliperidone palmitate once-monthly treatment in Hong Kong.

BACKGROUND: Very few data are available to demonstrate the economic benefit of early paliperidone palmitate once-monthly long-acting injectable (PP1M) treatment in patients with schizophrenia or schizoaffective disorder. METHODS AND MATERIALS: This study has retrospectively compared the healthcare utilization and associated costs of pre- and post-PPIM treatment in 413 patients with schizophrenia or schizoaffective disorder recruited from three major public hospitals providing psychiatric services in Hong Kong. Patients were categorized into early treatment (≤3 years since diagnosis) and chronic (>3 years) groups, and also whether they were receiving polypharmacy (POP). RESULTS: It was found that patients who were started on early therapy with no POP had the most favourable outcomes. Overall results of the entire cohort, including both early and late treatments, indicate that there was a slight increase in annual in-patient days (IP) per patient and outpatient visit (OP) by 3.18 and 1.87, respectively, and a decrease in emergency room visit (ER) of 0.9 (p < 0.05). For non-polypharmacy (NP) patients receiving early PP1M therapy, there was a significant decrease in IP and ER of 21.56 (p < 0.05) and 1.15 (p < 0.05), respectively, but an increase in OP of 1.88 (p < 0.05). For patients with POP, there was an all-across increase in IP and all-across decrease in OP and ER. In monetary terms, a NP patient receiving early therapy may have an overall saving of HKD40,878 (USD5,241, 1USD = 7.8HKD) per year compared to HKD6,224 (USD798) in patients where therapy was given after 3 years. For patients with POP, there was an all-across increase in overall spending despite reductions in OP and ER. CONCLUSIONS: From the 413 patients studied, potential annual savings is higher by early administration of PPIM in patients with NP. Analysis using multivariate linear regression based on generalized estimating equations and sensitivity analysis using a linear mixed model supported the findings.

Temperature-compensated fiber-optic 3D shape sensor based on femtosecond laser direct-written Bragg grating waveguides.

Temperature-compensated 3D fiber shape sensing is demonstrated with femtosecond laser direct-written optical and Bragg grating waveguides that were distributed axially and radially inside a single coreless optical fiber. Efficient light coupling between the laser-written optical circuit elements and a standard single-mode fiber (SMF) was obtained for the first time by 3D laser writing of a 1 × 3 directional coupler to meet with the core waveguide in the fusion-spliced SMF. Simultaneous interrogation of nine Bragg gratings, distributed along three laterally offset waveguides, is presented through a single waveguide port at 1 kHz sampling rate to follow the Bragg wavelength shifts in real-time and thereby infer shape and temperature profile unambiguously along the fiber length. This distributed 3D strain and thermal sensor is freestanding, flexible, compact, lightweight and opens new directions for creating fiber cladding photonic devices for a wide range of applications from shape and thermal sensing to guidance of biomedical catheters and tools in minimally invasive surgery.

Intraoperative handheld optical coherence tomography forward-viewing probe: physical performance and preliminary animal imaging.

A prototype intraoperative hand-held optical coherence tomography (OCT) imaging probe was developed to provide micron resolution cross-sectional images of subsurface tissue during open surgery. This new ergonomic probe was designed based on electrostatically driven optical fibers, and packaged into a catheter probe in the form factor of clinically accepted Bayonet shaped neurosurgical probes. Optical properties of the probe were measured to have a ~20 µm spot size, 5 mm working distance and 4 mm field of view. Feasibility of this probe for structural and Doppler shift imaging was tested on porcine femoral blood vessel imaging.

Microstructuring of polypyrrole by maskless direct femtosecond laser ablation.

Ultrafast laser micromachining was optimized for microstructuring polypyrrole as a facile new approach towards tailoring electrochemical and mechanical responses desirable for microactuator, sensors, neural probing, and nerve conduit applications. Laser perforation of high-density and high aspect ratio through-holes generated greater than 5-fold increase in surface area. The flexible machining technique offers micron-size resolution and fast prototyping capability for optimizing properties and opening new directions for polypyrrole-based devices.

Economic analysis between entecavir and lamivudine for the treatment of chronic hepatitis B in Hong Kong.

BACKGROUND AND AIM: Tremendous healthcare resources have been spent on the management of chronic hepatitis B (CHB) and its related complications. Therefore, a proper evaluation of the cost-effectiveness of pharmacotherapy is vital in aid of decision-making. The aim of the present study was to examine the long-term economic and clinical influence if lamivudine was replaced by entecavir in a group of CHB patients. METHODS: A recently published decision analytic model was adapted to study the cost-effectiveness of 2 years of treatment of entecavir in a hypothetical cohort of 1000 hepatitis B e antigen (HBeAg)-negative CHB patients from a public hospital perspective. Compensated cirrhosis (CC) and de-compensated cirrhosis (DC) and hepatocellular carcinoma (HCC) events were projected to 10 years. Hong Kong-specific health care costs were used. Quality Adjusted Life Years (QALYs) were calculated using the utility values obtained from a local study. RESULTS: In the base case analysis, compared with lamivudine, the use of entecavir was expected to reduce the incidences of CC, DC and HCC by 41.8%, 57.1% and 49.3%, respectively, and lead to a saving of $US 1.17 million in medical cost. The overall disease management cost for entecavir, which was 67.7% higher than lamivudine for 2 years treatment was reduced to 17.2% after projecting 2-year treatment duration to 10 years. The incremental cost per QALY gained for entecavir compared with lamivudine was $US 13 759. CONCLUSIONS: Based on the recommended cost-effectiveness threshold of the World Health Organization, entecavir is considered cost-effective compared with lamivudine in treating CHB in Hong Kong when long term medical consequences were considered.

A cost-minimisation analysis comparing different antibiotic regimens used in treating all-cause bacterial pneumonia in Hong Kong.

BACKGROUND: To find out the antibiotic treatment regimens with the lowest cost for all-cause bacterial pneumonia, a study to compare the costs of different antibiotic regimens in the treatment of patients diagnosed with all-cause bacterial pneumonia who required hospitalisation was carried out. METHODOLOGY: This was a multicentre, retrospective study of patient medical records. The primary aim was to examine whether the initial choice of antibiotic had affected the total cost of treatment, while the secondary aim was to find out whether the initial choice of antibiotic had affected the initial treatment failure rates and death rates. A cost-minimisation analysis (CMA) from a public hospital perspective was employed. RESULTS: A total of 333 patient medical case notes were reviewed. The most commonly prescribed antibiotic regimen was amoxycillin-clavulanate (AC) followed by amoxycillin-clavulanate plus macrolide (ACM) and quinolone (Q). In the study population, no statistical significance could be detected between the mean cost of the three regimens. In the subgroup analysis of patients with a history of chronic obstructive pulmonary disease (COPD) and patients with a history of smoking, the Q regimen appeared to be the least expensive. CONCLUSION: In the study population, no significant difference could be identified between the mean cost of the three antibiotic regimens. In a special populations such as patients with a history of COPD and patients with a history of smoking, the Q regimen appeared to be superior. Further studies in these areas are needed.

Interstitial Doppler optical coherence tomography as a local tumor necrosis predictor in photodynamic therapy of prostatic carcinoma: an in vivo study.

We have tested the feasibility of real-time localized blood flow measurements, obtained with interstitial (IS) Doppler optical coherence tomography (DOCT), to predict photodynamic therapy (PDT)-induced tumor necrosis deep within solid Dunning rat prostate tumors. IS-DOCT was used to quantify the PDT-induced microvascular shutdown rate in s.c. Dunning prostate tumors (n=28). Photofrin (12.5 mg/kg) was administered 20 to 24 hours before tumor irradiation, with 635 nm surface irradiance of 8 to 133 mWcm(-2) for 25 minutes. High frequency ultrasound and calipers were used to measure the thickness of the skin covering the tumor and the location of the echogenic IS probe within it. A two-layer Monte Carlo model was used to calculate subsurface fluence rates within the IS-DOCT region of interest (ROI). Treatment efficacy was estimated by percent tumor necrosis within the ROI, as quantified by H&E staining, and correlated to the measured microvascular shutdown rate during PDT treatment. IS-DOCT measured significant PDT-induced vascular shutdown within the ROI in all tumors. A strong relationship (R2=0.723) exists between the percent tumor necrosis at 24 hours posttreatment and the vascular shutdown rate: slower shutdown corresponded to higher treatment efficacy, i.e., more necrosis. Controls (needle+light, no drug, n=3) showed minimal microvascular changes or necrosis (4%+/-1%). This study has correlated a biological end point with a direct and localized measurement of PDT-induced microvascular changes, suggesting a potential clinical role of on-line, real-time microvascular monitoring for optimizing treatment efficacy in individual patients.

Omeprazole before endoscopy in patients with gastrointestinal bleeding.

BACKGROUND: A neutral gastric pH is critical for the stability of clots over bleeding arteries. We investigated the effect of preemptive infusion of omeprazole before endoscopy on the need for endoscopic therapy. METHODS: Consecutive patients admitted with upper gastrointestinal bleeding underwent stabilization and were then randomly assigned to receive either omeprazole or placebo (each as an 80-mg intravenous bolus followed by an 8-mg infusion per hour) before endoscopy the next morning. RESULTS: Over a 17-month period, 638 patients were enrolled and randomly assigned to omeprazole or placebo (319 in each group). The need for endoscopic treatment was lower in the omeprazole group than in the placebo group (60 of the 314 patients included in the analysis [19.1%] vs. 90 of 317 patients [28.4%], P=0.007). There were no significant differences between the omeprazole group and the placebo group in the mean amount of blood transfused (1.54 and 1.88 units, respectively; P=0.12) or the number of patients who had recurrent bleeding (11 and 8, P=0.49), who underwent emergency surgery (3 and 4, P=1.00), or who died within 30 days (8 and 7, P=0.78). The hospital stay was less than 3 days in 60.5% of patients in the omeprazole group, as compared with 49.2% in the placebo group (P=0.005). On endoscopy, fewer patients in the omeprazole group had actively bleeding ulcers (12 of 187, vs. 28 of 190 in the placebo group; P=0.01) and more omeprazole-treated patients had ulcers with clean bases (120 vs. 90, P=0.001). CONCLUSIONS: Infusion of high-dose omeprazole before endoscopy accelerated the resolution of signs of bleeding in ulcers and reduced the need for endoscopic therapy. (ClinicalTrials.gov number, NCT00164866 [ClinicalTrials.gov] .).

Non-invasive serological detection of Helicobacter pylori antigens in adult Hong Kong Chinese non-ulcer dyspepsia patients.

OBJECTIVE: The aim of our study was to evaluate the accuracy of the serology test kit (Signify H. pylori test), an office-based serological test and to compare relative performances with endoscopy, including biopsy urease tests (Clotest), histology, and culture when applied to dyspeptic adult patients in Hong Kong Chinese. METHODS: Prospective clinical trial was conducted at the Alice Ho Miu ling Nethersole Hospital (AHNH) outpatient endoscopy center from June to December 2004 and included adult Chinese patients who attended the endoscopy center. A research nurse interviewed consenting patients and whole blood samples were obtained via simple fingerstick were then and transferred to Signify test kits. The results were read after 5 minutes. The presence of two distinct lines within the result-reading window was treated as a positive result; a single distinct line was treated as a negative result. All patients underwent upper gastroduodenal endoscopy, and antral/antrum gastric biopsy specimens were taken and then processed for microbiological cultures. RESULTS: A total of 384 patients were recruited in the study and 131 (34.7%) patients were tested positive for H. pylori. Among them, 62 patients (47.3%) were detected by the Signify H. pylori test. The Signify serology test kit was 52.7% sensitive, 87.9% specific, and 75.7% accurate, respectively in the current study. CONCLUSION: The Signify H. pylori test showed a sub-optimal correlation between the presence of H. pylori infection and the serological test results in a Hong Kong Chinese population.

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.

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.

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.

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.

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.