Evaluation of health outcomes in osteoarthritis patients after total knee replacement: a two-year follow-up.

OBJECTIVES: To quantify the improvement in health outcomes in patients after total knee replacement (TKR). METHODS: This was a two-year non-randomized prospective observational study in knee osteoarthritis (OA) patients undergone TKR. Patients were interviewed one week before, six months after, and two years after surgery using a standardized questionnaire including the SF-36, the Oxford Knee Score (OKS), and the Knee Society Clinical Rating Scale (KSS). A generalized estimating equation (GEE) model was used to estimate the magnitudes of the changes with and without the adjustment of age, ethnicity, BMI, and years with OA. RESULTS: A total of 298 (at baseline), 176 (at six-months), and 111 (at two-years) eligible patients were included in the analyses. All the scores changed significantly over time, with the exception of SF-36 social functioning, vitality, and mental health. With the adjustment of covariates, the magnitude of changes in these scores was similar to those without the adjustment. CONCLUSIONS: Both general and knee-specific physical functioning had been significantly improved after TKR, while other health domains have not been substantially improved after the surgery.

Reproductive variables, soy intake, and lung cancer risk among nonsmoking women in the Singapore Chinese Health Study.

Lung cancer among nonsmokers has emerged as a distinct clinicopathologic entity for which the etiology is still poorly understood, but which accounts for a significant proportion of the lung cancers among women. Although estrogens have been shown to have mitogenic effects in lung cells and interact with growth factor pathways in tumorigenesis, epidemiologic evidence for a link between reproductive hormones and lung cancer is sparse and inconsistent. We examined the effect of parity, age at menarche/menopause, cycle length and use of exogenous hormones, and dietary soy and soy isoflavonoid intake on lung cancer risk in a prospective cohort of middle-aged and elderly Chinese women in Singapore among whom 91% were lifetime nonsmokers. Among 35,298 women (mean follow-up time, 9.6 years), 298 cases of incident lung cancer were recorded, of which 189 (63.4%) occurred in nonsmokers. Compared with nulliparous women, those with one to two, three to four, and more than five livebirths had relative risks of between 0.49 and 0.59 (P for trend<0.01) for all lung cancers, and between 0.32 and 0.42 (P for trend<0.001) for adenocarcinomas. This relationship was observed in both smokers and nonsmokers. Age at menarche and menopause did not seem to influence risk. Dietary soy isoflavonoid intake was associated with a statistically significant inverse trend among nonsmokers only (relative risks, 0.59 for highest versus lower quartile; P for trend, 0.021). These findings add support for the role of hormonal factors in the etiology of lung cancer among nonsmoking women, and are consistent with emerging experimental evidence in this regard.

Sleep duration, melatonin and breast cancer among Chinese women in Singapore.

BACKGROUND: Sleep duration has been hypothesized to be inversely associated with breast cancer risk, possibly due to greater overall melatonin production in longer sleepers. However, data are inconclusive from the three studies conducted in Western populations on sleep duration and breast cancer risk. METHODS: We investigated the relationship between self-reported usual sleep duration determined at baseline and subsequent risk of breast cancer in the prospective, population-based cohort of the Singapore Chinese Health Study. We excluded from the study women with <2 years of follow-up due to possible change in sleep pattern among breast cancer cases close to the time of diagnosis. Five hundred and twenty-five incident cases of breast cancer were identified among the remaining 33 528 women after up to 11 years of follow-up. RESULTS: Among women postmenopausal at baseline, breast cancer risk decreased with increasing sleep duration (P trend = 0.047); those who reported 9+ h of sleep showed a relative risk of 0.67 (95% confidence interval = 0.4-1.1) compared with women who reported < or =6 h of sleep. This inverse association was observed primarily in lean women [i.e. body mass index below the median value (23.2 kg/m(2))] (P = 0.024). In this study population, irrespective of gender, urinary 6-sulfatoxymelatonin levels increased with increasing self-reported hours of sleep (P trend = 0.035) after adjustment for age and time of day of urine collection. Melatonin levels were 42% higher in those with 9+ versus those with < or =6 h of sleep. CONCLUSION: Sleep duration may influence breast cancer risk, possibly via its effect on melatonin levels.

Chronic rhinosinusitis and risk of lung cancer in the Singapore Chinese Health Study.

Epidemiologic evidence suggests that chronic inflammatory conditions of the lung may increase lung cancer risk. These chronic conditions, such as chronic obstructive pulmonary disease and asthma, commonly coexist with chronic rhinosinusitis. We prospectively examined if chronic rhinitis or sinusitis was associated with lung cancer risk in the Singapore Chinese Health Study, a population-based cohort of 63,257 Singapore Chinese, who were aged 45-74 years when recruited between 1993 and 1998. Each subject completed a comprehensive interview on medical conditions, dietary and lifestyle factors at recruitment, and cancer occurrence and survival status were determined via linkage to population-based registries. As of 31 December, 2005, 954 cohort participants had developed lung cancer. Compared with subjects without such history, subjects who reported a history of physician-diagnosed rhinitis or sinusitis at baseline, whether allergic or nonallergic, had a statistically significant 59% increase in risk of lung cancer (hazard ratio [HR] = 1.59; confidence interval [CI] = 1.06-2.37). This association was significant and stronger in women (HR = 2.32; 95% CI = 1.23-4.39) compared to men, and for the adenocarcinoma cell type (HR = 1.91; 95% CI = 1.07-3.42) compared to other histologies. Overall, a history of asthma, hay fever, allergic dermatitis, food allergy or any other allergic conditions asked in a single question was not related to lung cancer risk (HR = 1.11; 95% CI = 0.90-1.36). Chronic rhinosinusitis may be a marker of pan-airway inflammation and its association with lung cancer risk provides evidence linking inflammation to lung carcinogenesis, especially among women.

Sleep duration and coronary heart disease mortality among Chinese adults in Singapore: a population-based cohort study.

While some studies have found a positive association between both short and long sleep durations and cardiovascular disease (CVD), others have found an association only with a long or short sleep duration. In addition, there are limited data from non-Western populations on this topic. The authors examined the association between sleep duration and coronary heart disease (CHD) mortality among Chinese adults in Singapore (1993-2006), performing a prospective cohort study among 58,044 participants aged > or =45 years (55.9% women) without preexisting CVD. The main outcome of interest was CHD mortality (n = 1,416). The authors found both short and long sleep durations to be positively associated with CHD mortality, independent of smoking, alcohol intake, and body mass index. Compared with persons with a sleep duration of 7 hours (referent), the multivariable relative risk of CHD mortality for a sleep duration of < or =5 hours was 1.57 (95% confidence interval: 1.32, 1.88); for a sleep duration of > or =9 hours, it was 1.79 (95% confidence interval: 1.48, 2.17). This association persisted in subgroup analyses by sex and body mass index. In a population-based cohort of Chinese adults from Singapore, sleep durations of < or =5 hours and > or =9 hours (versus 7 hours) were modestly associated with CHD mortality. These results suggest that sleep duration may be an important marker for CVD.

Morbidity and mortality in relation to smoking among women and men of Chinese ethnicity: the Singapore Chinese Health Study.

OBJECTIVES: We examined the association among cigarette smoking, smoking cessation and a broad range of cancer incidence and all cause and cause-specific mortality in a population-based cohort of adults of Chinese ethnicity in Singapore. METHODS: Subjects were 61,320 participants of the Singapore Chinese Health Study (44.5% men, aged 45-74 years, recruitment from 1993-1998) who were free of cancer at the baseline examination. Main outcomes-of-interest included cancer incidence, all cause and cause-specific mortality as of December 31, 2005. RESULTS: Cigarette smoking was positively associated with overall cancer incidence, including cancers at the following specific sites: head and neck region, upper gastrointestinal tract, hepatobiliary and pancreas cancer, lung, and bladder/renal pelvis cancer. Compared to never smokers, the relative risk (RR) (95% confidence interval [CI]) of cancer incidence (all cancer sites) among current smokers smoking >22 cigarettes/day was 1.9 (1.7-2.1), p-trend<0.0001. Similarly, cigarette smoking was associated with all cause and cause-specific mortality, including deaths due to cancer, ischemic heart disease, other heart diseases, and chronic obstructive pulmonary disease. Compared to never smokers, RR (95%CI) of all cause mortality among current smokers smoking >22 cigarettes/day was 1.8 (1.6-2.0), p-trend<0.0001. Also, relative to current smokers, ex-smokers experienced reduced cancer incidence and total mortality. The population attributable risk of smoking in men for cancer incidence as well as all-cause mortality was 23%, whereas in women it ranged from 4-5%. CONCLUSIONS: Cigarette smoking is an important risk factor for cancer incidence and major causes of mortality in Chinese men and women of Singapore.

Cost effectiveness analysis of population-based serology screening and (13)C-Urea breath test for Helicobacter pylori to prevent gastric cancer: a markov model.

AIM: To compare the costs and effectiveness of no screening and no eradication therapy, the population-based Helicobacter pylori (H pylori) serology screening with eradication therapy and (13)C-Urea breath test (UBT) with eradication therapy. METHODS: A Markov model simulation was carried out in all 237900 Chinese males with age between 35 and 44 from the perspective of the public healthcare provider in Singapore. The main outcome measures were the costs, number of gastric cancer cases prevented, life years saved, and quality-adjusted life years (QALYs) gained from screening age to death. The uncertainty surrounding the cost-effectiveness ratio was addressed by one-way sensitivity analyses. RESULTS: Compared to no screening, the incremental cost-effectiveness ratio (ICER) was $16166 per life year saved or $13571 per QALY gained for the serology screening, and $38792 per life year saved and $32525 per QALY gained for the UBT. The ICER was $477079 per life year saved or $390337 per QALY gained for the UBT compared to the serology screening. The cost-effectiveness of serology screening over the UBT was robust to most parameters in the model. CONCLUSION: The population-based serology screening for H pylori was more cost-effective than the UBT in prevention of gastric cancer in Singapore Chinese males.

Green tea and black tea consumption in relation to colorectal cancer risk: the Singapore Chinese Health Study.

The relationships between green tea and black tea consumption and colorectal cancer risk were examined within the Singapore Chinese Health Study, a prospective cohort study of diet and cancer involving >60,000 men and women. Intake of green tea and black tea was assessed through in-person interviews. Incident cancer cases and deaths among cohort members were identified through record linkage of the cohort database with respective databases from the nationwide Singapore Cancer Registry and the Singapore Registry of Births and Deaths. The proportional hazard regression method was used to examine the associations between intake of green and black tea separately and colorectal cancer risk with adjustment for potential confounders. After an average of 8.9 years of follow-up, 845 colorectal cancer cases were identified. Subjects who drank green tea exhibited a statistically non-significant increase in risk [relative risk (RR) = 1.12, 95% confidence interval (CI) = 0.97-1.29] relative to non-drinkers of green tea. This risk increase was mainly confined to men (RR = 1.31, 95% CI = 1.08-1.58); the comparable RR in women was 0.89 (95% CI = 0.71-1.12). In men, the green tea-colorectal cancer association was noted mainly in those with advanced disease (Duke C or D) (RR = 1.53, 95% CI = 1.19-1.97), and the association was dose dependent (P for trend = 0.0002). This latter association was especially strong within the colon subsite (RR = 1.75, 95% CI = 1.24-2.46; P for trend < 0.0001). Irrespective of gender, intake of black tea was not associated with risk of colorectal cancer (RR = 0.92, 95% CI = 0.79-1.07) in this Asian population.

Angiotensin I-converting enzyme (ACE) gene polymorphism and breast cancer risk among Chinese women in Singapore.

Angiotensin II has been shown to have possible mitogenic and angiogenic effects in human cell lines and animal models of breast cancer. It is converted from its precursor to its active form by the angiotensin I-converting enzyme (ACE). A recent epidemiological study observed lower breast cancer incidence in female users of ACE inhibitors relative to nonusers with comparable cardiovascular conditions. To study the hypothesis that reduced ACE activity is associated with reduced risk of breast cancer, we conducted a nested case-control study within the Singapore Chinese Health Study Cohort to investigate the associations between the ACE A-240T and I/D gene polymorphisms, and breast cancer risk. For this analysis, 189 incident breast cancer cases and 671 female cohort control subjects were compared. The low-activity A and I alleles were the putative "low-risk" alleles. The I/D and A-240T genotypes exhibited significant linkage disequilibrium among Singapore Chinese (contingency coefficient = 0.74; P < 0.001). With adjustment for breast cancer risk factors, women with one or two copies of the low activity A allele showed a statistically significant reduction in risk compared with those with the TT genotype [odds ratio (OR), 0.55; 95% confidence interval (CI), 0.34-0.90]. The risk reduction was enhanced after excluding subjects with medical conditions for which ACE inhibitors are commonly prescribed (OR, 0.49; 95% CI, 0.27-0.89). Comparable results were obtained with respect to the I/D genotype and risk of breast cancer. When the I/D and A-240T genotypes were considered simultaneously, compared with women with the high-activity genotypes (either TT or DD or both), those with the low-activity genotypes (presence of both A and I alleles) exhibited lower breast cancer risk (OR, 0.46; 95% CI, 0.27-0.81). Our findings support experimental data implicating ACE and angiotensin II in breast cancer, and suggest that the renin-angiotensin system may serve as a therapeutic target for breast cancer treatment and prevention.

Data quality at the Singapore Cancer Registry: An overview of comparability, completeness, validity and timeliness.

AIM: To provide a comprehensive evaluation of the quality of the data at the Singapore Cancer Registry (SCR). METHODS: Quantitative and semi-quantitative methods were used to assess the comparability, completeness, accuracy and timeliness of data for the period of 1968-2013, with focus on the period 2008-2012. RESULTS: The SCR coding and classification systems follow international standards. The overall completeness was estimated at 98.1% using the flow method and 97.5% using the capture-recapture method, for the period of 2008-2012. For the same period, 91.9% of the cases were morphologically verified (site-specific range: 40.4-100%) with 1.1% DCO cases. The under-reporting in 2011 and 2012 due to timely publication was estimated at 0.03% and 0.51% respectively. CONCLUSION: This review shows that the processes in place at the SCR yields data which are internationally comparable, relatively complete, valid, and timely, allowing for greater confidence in the use of quality data in the areas of cancer prevention, treatment and control.

A new single nucleotide polymorphism in the insulin-like growth factor I regulatory region associates with colorectal cancer risk in singapore chinese.

Elevated levels of plasma insulin-like growth factor I (IGF-I) are a potential risk factor for several cancers, including colorectal cancer. Physiologic levels of plasma IGF-I vary greatly; this variation may be in part genetically determined. We identified two single nucleotide polymorphisms (SNP) in perfect linkage disequilibrium with each other and in partial linkage disequilibrium with a previously studied cytosine-adenine microsatellite [-969(CA)(n)]. We investigated one of the SNPs, -533T/C,and the 969(CA)(n) in relation to the risk of colorectal cancer in a case-control study nested within a cohort of Singapore Chinese (cases/controls = 290:873). The (CA)(21) allele, rather than the previously implicated (CA)(19) allele, was associated with a reduced risk of colorectal cancer (odds ratio for 21/21 versus all other genotypes, 0.48; 95% confidence interval, 0.28-0.84). For the -533C/T SNP, persons carrying one or more copies of the C allele had a decreased in risk of colorectal cancer compared with noncarriers (odds ratio for CC/CT versus TT, 0.58; 95% confidence interval, 0.41-0.82). This association was specific for colon, as opposed to rectal cancer and was modified by age. We also examined a functional insulin-like growth factor binding protein (IGFBP3) promoter SNP, -202 A/C, previously reported to predict serum IGFBP3 levels. Although we were able to confirm this genotype-phenotype association, the -202A/C IGFBP3 SNP was not significantly associated with colorectal cancer risk. In conclusion, we report a novel SNP in the IGF-I regulatory region that is associated with colorectal cancer risk.

Dietary cryptoxanthin and reduced risk of lung cancer: the Singapore Chinese Health Study.

High prediagnostic serum beta-cryptoxanthin levels have been found to be associated with reduced risk of lung cancer in a recent cohort study of Chinese men in Shanghai, China. Data on dietary beta-cryptoxanthin, and other specific carotenoids and antioxidants in relation to lung cancer, particularly in non-Western populations, are scarce. The aim of the present study was to assess the roles of dietary antioxidants in the development of lung cancer. Between April 1993 and December 1998, 63,257 Chinese men and women ages 45-74 years in Singapore participated in a prospective study of diet and cancer. At baseline, an in-person interview was conducted using a structured questionnaire for information on usual dietary habits, tobacco smoking, and other lifestyle factors. A Singapore food composition database was used to estimate intake of alpha-carotene, beta-carotene, beta-cryptoxanthin, lycopene, lutein/zeaxanthin, vitamins A, C, and E, and folate in study subjects. During the first 8 years of follow-up, 482 lung cancer cases occurred among cohort members. High levels of dietary beta-cryptoxanthin were associated with reduced risk of lung cancer; relative to the lowest quintile, the self-reported smoking adjusted relative risks (95% confidence intervals) for the highest quintile were 0.73 (0.54-0.98) among all of the subjects and 0.63 (0.41-0.99) among current smokers. Before adjustment for cigarette smoking, dietary vitamin C was associated with a statistically significant reduction in risk of lung cancer. However the inverse vitamin C-lung cancer association was largely explained by smoking and dietary beta-cryptoxanthin. Other carotenoids (alpha-carotene, beta-carotene, lycopene, and lutein/zeaxanthin), vitamins A and E, and folate were not associated significantly with lung cancer risk after adjustment for cigarette smoking. We recognized that potential measurement errors in cigarette smoking may exert an effect on the dietary beta-cryptoxanthin-lung cancer association. After additional adjustments were made for the residual confounding by smoking using statistical models, about 15-40% reduction in risk of lung cancer was seen for subjects in the highest versus lowest 10th percentile of dietary beta-cryptoxanthin. The present study lends additional credence to prior experimental and epidemiological data in support of the hypothesis that dietary beta-cryptoxanthin is a chemopreventive agent for lung cancer in humans.

Soy intake and other lifestyle determinants of serum estrogen levels among postmenopausal Chinese women in Singapore.

Endogenous estrogen levels are strongly associated with breast cancer risk, but its determinants are not well understood. We conducted a cross-sectional study of 144 healthy postmenopausal women, participants in a population-based prospective investigation of diet and cancer risk among Chinese in Singapore. The relationships between plasma levels of estrone (E(1)), estradiol (E(2)), and androstenedione and dietary intake of soy and other food groups were investigated. Data on diet and other lifestyle factors were obtained from a structured questionnaire with a validated dietary component that was administered in-person to all participants. Few dietary factors emerged as determinants of plasma estrogen levels in this population. An exception was soy, which was significantly associated with plasma E(1) levels. Specifically, E(1) levels were 15% lower among individuals in the highest quartile of soy protein intake compared with those in the lower three quartiles of intake (P = 0.047). E(1) levels did not differ between individuals in the lower three quartiles of soy protein intake. Similar patterns of differences in E(1) levels emerged in analyses by intake of isoflavones and total soy products. These findings on soy were independent of the four nondietary factors (see below) that significantly influenced estrogen levels. Both E(1) and E(2) levels increased with high body mass index [BMI (weight/height(2))]; the respective levels were 41% (two-sided P = 0.02) and 17% higher (P = 0.34) among women in the highest BMI category (BMI >/= 24) compared with those in the lowest category (BMI < 20). After adjustment for BMI and age, women with a late age at menarche (age 17 years or older) showed significantly lower E(1) (30% lower; P = 0.02) and E(2) levels (24% lower; P = 0.02) compared with women with earlier age at menarche (before age 17 years) and who were nulliparous or had a late age at first live birth (after age 31 years). Current smokers showed significantly higher E(2) levels (28%) than nonsmokers (P = 0.04). These findings are discussed in relation to the recent doubling of breast cancer incidence among Chinese women in Singapore.

Mammographic parenchymal patterns and self-reported soy intake in Singapore Chinese women.

The study aimed to investigate whether self-reported dietary variables were associated with mammographic parenchymal patterns, which have been shown to predict risk of breast cancer. Among the 3,421 women, ages 45-74 years, common to two independent population-based cohorts, mammographic parenchymal patterns and current dietary habits were assessed for 406 randomly chosen participants. Logistic regression methods were used to compare dietary and other lifestyle profiles between subjects classified as displaying high (cases) and low risk (controls) parenchymal patterns. After adjustment for energy intake and other potential confounders, dietary soy protein intake was inversely related to risk of high-risk parenchymal pattern (odds ratio, 0.41; 95% confidence interval, 0.18-0.94, highest versus lowest quartile of intake). Similarly, the highest versus lowest quartile of dietary soy isoflavone intake was significantly related to low-risk parenchymal patterns (odds ratio, 0.44; 95% confidence interval, 0.20-0.98). The association between high soy intake and a reduced risk of mammographic parenchymal patterns that are associated with high breast cancer risk may have important implications in breast cancer prevention.

Dietary soy and increased risk of bladder cancer: the Singapore Chinese Health Study.

The association between soyfood consumption and subsequent bladder cancer risk was investigated in a population-based cohort study, the Singapore Chinese Health Study. As of December 31, 2000, 329,848 person-years of follow-up were accrued. Sixty-one histologically confirmed incident bladder cancer cases were identified. Information on soyfood consumption at baseline was obtained through in-person interviews using a validated dietary questionnaire. Relative risks and 95% confidence intervals were calculated using the Cox proportional hazard regression method. High intake of soyfood was statistically significantly related to an elevated risk of bladder cancer. Relative to the lowest quartile of energy-adjusted total soy intake (<36.9 g/1000 Kcal), the highest quartile of total soy intake (> or =92.5 g/1000 Kcal) was associated with a 2.3-fold increase in bladder cancer risk (95% confidence interval = 1.1-5.1) after adjustment for cigarette smoking and level of education. Similar results were obtained for intakes of soy protein and soy isoflavones. The soyfood-bladder cancer risk association did not differ significantly between men and women and was not explained by other dietary factors. The soy-cancer relationship became stronger when the analysis was restricted to subjects with longer (> or =3 years) duration of follow-up. To our knowledge, this is the first epidemiological report on the effect of dietary soy on bladder cancer risk.

Determinants of circulating insulin-like growth factor I and insulin-like growth factor binding protein 3 concentrations in a cohort of Singapore men and women.

Variation in the circulating concentrations of the insulin-like growth factor (IGF) system has been implicated in the etiology of chronic diseases including cancer (prostate, breast, colon, and lung), heart disease, type 2 diabetes, and osteoporosis. We searched for sociodemographic, anthropometric, reproductive, lifestyle, and dietary determinants of IGF-I and insulin-like growth factor binding protein (IGFBP) -3 serum concentrations. Serum samples were collected in a Singapore Chinese cohort with a mean age of 61 years. Subject information was assessed during an in-person interview. Radioimmunometrically measured IGF-I and IGFBP-3 concentrations were available for 312 men and 326 postmenopausal women ages 50 years or older. Mean IGF-I concentrations were 144 ng/ml and 121 ng/ml for men and women, respectively (gender difference, P < 0.0001), and mean IGFBP-3 concentrations were 3710 ng/ml and 4147 ng/ml for men and women, respectively (gender difference, P < 0.0001). IGF-I and IGFBP-3 decreased with age (P for trend <0.0001); the age-related decrease in the IGF-I:IGFBP-3 molar ratio was stronger in women than men. IGF-I concentrations were higher among physically inactive subjects and among women with an early age at menarche. Consumption of saturated fat was found to decrease, and intake of omega-3 polyunsaturated fatty acids and of dietary fiber was found to increase circulating IGFBP-3 concentrations. Intake of calcium from food and supplement was associated positively with circulating IGF-I, IGFBP-3, and molar ratio. Intake of soy was associated positively with IGF-I and molar ratio concentrations, but only in men. The results of this study lend additional support to the hypothesis that circulating IGF-I concentrations increase the risk of prostate, bladder, colorectal, and breast cancer.

A tale of two cities: community psychobehavioral surveillance and related impact on outbreak control in Hong Kong and Singapore during the severe acute respiratory syndrome epidemic.

OBJECTIVES: To compare the public's knowledge and perception of SARS and the extent to which various precautionary measures were adopted in Hong Kong and Singapore. DESIGN: Cross-sectional telephone survey of 705 Hong Kong and 1,201 Singapore adults selected by random-digit dialing. RESULTS: Hong Kong respondents had significantly higher anxiety than Singapore respondents (State Trait Anxiety Inventory [STAI] score, 2.06 vs 1.77; P < .001). The former group also reported more frequent headaches, difficulty breathing, dizziness, rhinorrhea, and sore throat. More than 90% in both cities were willing to be quarantined if they had close contact with a SARS case, and 70% or more would be compliant for social contacts. Most respondents (86.7% in Hong Kong vs 71.4% in Singapore; P < .001) knew that SARS could be transmitted via respiratory droplets, although fewer (75.8% in Hong Kong vs 62.1% in Singapore; P < .001) knew that fomites were also a possible transmission source. Twenty-three percent of Hong Kong and 11.9% of Singapore respondents believed that they were "very likely" or "somewhat likely" to contract SARS during the current outbreak (P < .001). There were large differences between Hong Kong and Singapore in the adoption of personal precautionary measures. Respondents with higher levels of anxiety, better knowledge about SARS, and greater risk perceptions were more likely to take comprehensive precautionary measures against the infection, as were older, female, and more educated individuals. CONCLUSION: Comparative psychobehavioral surveillance and analysis could yield important insights into generic versus population-specific issues that could be used to inform, design, and evaluate public health infection control policy measures.

Omega-3 fatty acids and selenium as coronary heart disease risk modifying factors in Asian Indian and Chinese males.

OBJECTIVE: Asian Indian men are reported to have a higher incidence of coronary heart disease than men of other ethnic groups worldwide. Among the many hypotheses, one possible risk factor may be related to their dietary habits. This study estimated the plasma concentrations of fatty acids, antioxidant vitamins, and selenium in Indians and Chinese of Singapore. METHODS: The study population consisted of 145 Indian men and 147 Chinese men ages 26 to 79 y from a cross-sectional survey, the National University of Singapore Heart Study. RESULTS: Our findings indicated that Indians had lower plasma concentrations of docosahexanoic acid (3.07% versus 3.54%, P < 0.001), alpha-linolenic acid (0.48% versus 0.57%, P < 0.001), and total omega-3 fatty acids (4.71% versus 5.27%, P < 0.001) than did the Chinese. Arachidonic acid was higher in Indians (4.83%) than in the Chinese (4.51%, P = 0.007). The ratio of omega-3 acid to omega-6 fatty acid was also lower in Indians (0.15) than in the Chinese (0.16, P = 0.007). There were no significant differences in the concentrations of monounsaturated fatty acids, but saturated fatty acids were higher in Indians (39.17%) than in the Chinese (38.28%, P < 0.001). Analysis of vitamins A, C, and E showed no significant differences between Indians (0.67, 5.72, and 13.04 mg/L, respectively) and Chinese (0.68, 6.48, and 12.71 mg/L, respectively); however, serum concentration of selenium in Indians (117.49 microg/L) was significantly lower than in the Chinese (126.72 microg/L, P < 0.001). CONCLUSION: The results suggest that lower plasma concentrations of omega-3 fatty acids and selenium and higher concentrations of arachidonic acid and saturated fatty acids in Indians may reflect lower intakes of marine foods and, as a consequence, higher susceptibility to coronary heart disease.

Total or partial knee replacement? Cost-utility analysis in patients with knee osteoarthritis based on a 2-year observational study.

The objective of this study was to evaluate incremental cost-utility of total knee replacement (TKR) versus unicompartmental knee arthroplasty (UKA) in patients with knee osteoarthritis (OA) of the medial compartment. A 2-year non-randomised prospective observational cohort study was conducted in unicompartmental knee osteoarthritis patients scheduled for TKR (n = 431) or UKA (n = 102). Costs were identified using administrative databases and health outcomes were measured using the SF-36 and the Oxford knee score (OKS) 1 week before, 6 months after, and 2 years after surgery. The incremental cost-utility ratio (ICUR) for TKR versus UKA was calculated and its 95% confidence interval estimated using a nonparametric bootstrapping technique. Cost-effectiveness acceptability curves were constructed from different perspectives. On average, from the societal perspective, the ICUR was US $65,245 per quality-adjusted life-year (QALY). In the scenario with costs calculated from the perspective of patients, the ICUR was $60,382/QALY. This value decreased to $4,860/QALY in the scenario with costs calculated from the governmental perspective. However, the 95% confidence interval of ICURs cannot be defined because more than 5% bootstrapped samples fell into the upper left quadrant of the cost-effectiveness plane from all three perspectives. Based on the 2-year data, TKR gained more QALYs at higher costs compared to UKA. A long-term prospective study is necessary to determine cost-effectiveness of TKR and UKA.