Genome-wide association study of chronic sputum production implicates loci involved in mucus production and infection.

BACKGROUND: Chronic sputum production impacts on quality of life and is a feature of many respiratory diseases. Identification of the genetic variants associated with chronic sputum production in a disease agnostic sample could improve understanding of its causes and identify new molecular targets for treatment. METHODS: We conducted a genome-wide association study (GWAS) of chronic sputum production in UK Biobank. Signals meeting genome-wide significance (p<5×10-8) were investigated in additional independent studies, were fine-mapped and putative causal genes identified by gene expression analysis. GWASs of respiratory traits were interrogated to identify whether the signals were driven by existing respiratory disease among the cases and variants were further investigated for wider pleiotropic effects using phenome-wide association studies (PheWASs). RESULTS: From a GWAS of 9714 cases and 48 471 controls, we identified six novel genome-wide significant signals for chronic sputum production including signals in the human leukocyte antigen (HLA) locus, chromosome 11 mucin locus (containing MUC2, MUC5AC and MUC5B) and FUT2 locus. The four common variant associations were supported by independent studies with a combined sample size of up to 2203 cases and 17 627 controls. The mucin locus signal had previously been reported for association with moderate-to-severe asthma. The HLA signal was fine-mapped to an amino acid change of threonine to arginine (frequency 36.8%) in HLA-DRB1 (HLA-DRB1*03:147). The signal near FUT2 was associated with expression of several genes including FUT2, for which the direction of effect was tissue dependent. Our PheWAS identified a wide range of associations including blood cell traits, liver biomarkers, infections, gastrointestinal and thyroid-associated diseases, and respiratory disease. CONCLUSIONS: Novel signals at the FUT2 and mucin loci suggest that mucin fucosylation may be a driver of chronic sputum production even in the absence of diagnosed respiratory disease and provide genetic support for this pathway as a target for therapeutic intervention.

Effects of an individualised exercise programme plus Behavioural Change Enhancement (BCE) strategies for managing fatigue in frail older adults: a cluster randomised controlled trial.

BACKGROUND: To the best of our knowledge, although ageing-induced fatigue could cause adverse outcomes such as frailty, there is currently no intervention for it. This study evaluated the effects of an individualised exercise programme with/without BCE strategies on reducing fatigue in older adults. METHODS: A three-armed cluster-randomised controlled trial (RCT) was conducted with 184 participants (mean age: 79.1 ± 6.4; mean frailty score: 2.8 + 0.8) from 21 community centres (ClinicalTrials.gov: NCT03394495). They were randomised into either: the COMB group (n = 64), receiving 16 weeks of exercise training plus the BCE programme; the EXER group (n = 65), receiving exercise training and health talks; or the control group (n = 55), receiving only health talks. Fatigue was assessed using the Multi-dimensional Fatigue Inventory (range: 20 to 100, with higher scores indicating higher fatigue levels) at baseline, and immediately, 6 months, and 12 months post-intervention. RESULTS: The GEE analyses showed significant interaction (time x group) between the COMB and control groups immediately (p < 0.001), 6 months (p < 0.001), and 12 months (p < 0.001) post-intervention. Comparing the COMB and EXER groups, there was a significant interaction immediately (p = 0.013) and at 12 months post-intervention (p = 0.007). However, no significant difference was seen between the EXER group and control group at any time point. CONCLUSIONS: The COMB intervention showed better immediate and sustainable effects (i.e., 12 months after the intervention) on reducing fatigue in frail older adults than exercise training or health education alone. TRIAL REGISTRATION: ClinicalTrials.gov (NCT03394495), registered on 09/01/2018.

Changes in relative peripheral refraction in children who switched from single-vision lenses to Defocus Incorporated Multiple Segments lenses.

PURPOSE: To investigate changes in relative peripheral refraction (RPR) associated with myopia progression in children who wore single-vision (SV) lenses for 2 years and switched to Defocus Incorporated Multiple Segments (DIMS) lenses in the third year versus children who wore DIMS lenses for 3 years. METHODS: In the first 2 years, children were allocated randomly to wear either DIMS or SV lenses. In the third year, children in the DIMS group continued to wear these lenses, while those in the SV group were switched to DIMS lenses (Control-to-DIMS group). Central and peripheral refraction and axial length were monitored every 6 months. RESULTS: Over 3 years, the DIMS group (n = 65) showed good myopia control and maintained a relatively constant and symmetrical RPR profile without significant changes. In the first 2 years, children who wore SV lenses (n = 55) showed asymmetrical RPR changes, with significant increases in hyperopic RPR at 20° nasal (N) (mean difference: 0.88 ± 1.06 D, p < 0.0001) and 30N (mean difference: 1.07 ± 1.09 D, p < 0.0001). The Control-to-DIMS group showed significant myopia retardation after wearing DIMS lenses in the third year. When compared with the RPR changes in the first 2 years, significant reductions in hyperopic RPR were observed at 20N (mean difference: -1.14 ± 1.93 D, p < 0.0001) and 30N (mean difference: -1.07 ± 1.17 D, p < 0.0001) in the third year. However, no significant difference between the RPR changes found in the nasal retina and temporal retina (p > 0.05) was noted in the third year. CONCLUSION: Symmetrical changes in RPR were found in children switching from SV to DIMS lenses, and a symmetrical pattern of RPR was noted in children who wore DIMS for 3 years. Myopia control using myopic defocus in the mid-periphery influenced the RPR changes and retarded myopia progression by altering the eye's growth pattern.

Effects of a transitional home-based care program for stroke survivors in Harbin, China: a randomized controlled trial.

BACKGROUND: China has the biggest stroke burden in the world. Continued measures have been taken to enhance post-stroke rehabilitation management in the last two decades. The weak link is with home-based rehabilitation, with more attention and resources devoted to inpatient rehabilitation. OBJECTIVE: to address the service gap, this study tested a home-based transitional care model for stroke survivors. METHODS: a randomized controlled trial was conducted from February 2019 to May 2020 in Harbin, China, involving 116 patients with ischemic stroke. The intervention group participants (n = 58, 50%) received a 12-week home-based care program with components of transitional care measures and the national guidelines for facilitating patients to perform home-based exercises with continued monitoring and gradual progression. Control group participants received standard care including medication advice, rehabilitation exercise and one nurse-initiated follow-up call. Data were collected at baseline and after a 90-day (post-intervention) and a 180-day (post-intervention) follow-up. The primary outcome was quality of life (QOL), measured using the EuroQol-Five Dimension 5-Level scale (EQ-5D-5L). RESULTS: both intervention and control groups showed improvement in EQ-5D-5L from baseline to post-intervention (0.66 versus 0.83, P < 0.001) and (0.66 versus 0.77, P < 0.001), respectively, and there was significant group-by-time interaction in EuroQol-Visual Analogue Scale from baseline to post-intervention at 90 days and follow-up at 180 days with the intervention group experiencing better improvement. Similarly, significant interaction effects were also found in the Stroke Impact Symptom scale, self-efficacy and modified Barthel Index. CONCLUSIONS: home-based transitional care was effective in improving QOL, symptoms, self-efficacy and activities of daily living.

Validation of the National Health And Nutritional Survey (NHANES) single-item self-reported sleep duration against wrist-worn accelerometer.

PURPOSE AND METHODS: This study aimed to validate the single-item sleep duration question used in the National Health And Nutritional Survey (NHANES), "How much sleep do you usually get at night on weekdays or workdays (hours)?", against a wrist-worn accelerometer (ActiGraph GT3X +) in waves 2011-2012 and 2013-2014 among an adult population aged 20 or above (n = 8,438, mean age 49.7, 48% male). RESULTS: The accelerometer-measured and self-reported sleep duration were 6.01 (SD 1.48) and 6.88 (SD 1.40) h/day, respectively, representing a 0.87 h/day of over-reporting (SD 1.90, p < 0.001). Such an over-reporting was observed in all subgroups, where the over-reporting ranged from 0.72 (those aged 41-50) to 1.13 h/day (those aged 71 or above). The correlation between accelerometer-measured and self-reported sleep duration was low (ρ = 0.14, p < 0.001). CONCLUSIONS: The associations between sleep duration and other health outcomes identified using NHANES data should be further tested using more accurate and valid measures of sleep duration.

Bedtime smart device usage and accelerometer-measured sleep outcomes in children and adolescents.

PURPOSE: We analyzed the association between bedtime smart device usage habits and accelerometer-measured sleep outcomes (total sleeping time, sleep efficiency, and wake after sleep onset) in Hong Kong children and adolescents aged 8-14. METHODS: A total of 467 students in Hong Kong participated in this study from 2016 to 2017. They self-reported their bedtime smart device usage habits. The primary caregiver of each participant was also invited to complete a self-administered questionnaire about the family's social-economic status and bedtime smart device usage habits. An ActiGraph GT3X accelerometer was used to assess participants' 7-day sleep outcomes. RESULTS: The mean age of the participants was 10.3 (SD 1.9), and 54% were girls. Among the participants, 27% (n = 139) used a smart device before sleep, and 33% (n = 170) kept the smart device on before sleep. In total, 27% (n = 128) placed the smart device within reach before sleep, 23% (n = 107) would wake up when notifications were received, and 25% (n = 117) immediately checked the device after being awakened by a notification. Multiple regression controlling for age, sex, socio-economic status, and other confounders showed that those who woke up after receiving a notification had a statistically longer sleeping time (19.7 min, 95% CI: 0.3, 39.1, p = 0.046), lower sleep efficiency (- 0.71%, 95% CI - 1.40, - 0.02, p = 0.04), and a longer wake after sleep onset (2.6 min, 95% CI: 0.1, 5.1, p = 0.045) than those who did not. Nonetheless, all primary caregivers' bedtime smart device habits were insignificantly associated with all sleep outcomes of their children. CONCLUSION: Those who woke up after receiving smart device notifications had lower sleep efficiency and longer wake after sleep onset than those who did not, and they compensated for their sleep loss by lengthening their total sleep time.

Temporal association between objectively measured smartphone usage, sleep quality and physical activity among Chinese adolescents and young adults.

We studied the association between objectively measured smartphone usage and objectively measured sleep quality and physical activity for seven consecutive days among Hong Kong adolescents and young adults aged 11-25 years (n = 357, 67% female). We installed an app that tracked the subjects' smartphone usage and had them wear an ActiGraph GT3X accelerometer on their wrist to measure their sleep quality and physical activity level. Smartphone usage data were successfully obtained from 187 participants (52.4%). The participants on average spent 2 h 46 min per day on their smartphone. Multilevel regression showed that 1 min of daytime smartphone usage was associated with 0.07 min decrease in total sleeping time that night (p = .043, 95% confidence interval [CI]: -0.14, -0.003). Broken down for different usage purposes, 1 min of daytime social network usage and games and comics was associated with a 0.28 (p = .02, 95% CI: -0.52, -0.04) min and 0.18 min (p = .01, 95% CI: -0.32, -0.04) decrease in total sleeping time that night, respectively. One minute of daytime smartphone usage was associated with an increase of 4.55 steps in the number of steps (p = .001, 95% CI: 1.77, 7.34) on the next day. To conclude, time spent on a smartphone in the daytime was associated with total sleeping time that night and number of steps the next day, but was not associated with sleep efficiency, wake after sleep onset and moderate-to-vigorous-intensity activity (MVPA) among Hong Kong adolescents and young adults.

Sleep pattern in the US and 16 European countries during the COVID-19 outbreak using crowdsourced smartphone data.

BACKGROUND: To stop the spread of the new coronavirus disease in 2019 (COVID-19), many countries had completely locked down. This lockdown restricted the everyday life of the affected residents and changed their mobility pattern, but its effects on sleep pattern were largely unknown. METHODS: Here, utilizing one of the largest crowdsourced database (Sleep as Android), we analyzed the sleep pattern of 25 217 users with 1 352 513 sleep records between 1 January and 29 April 2020 in the US and 16 European countries (Germany, UK, Spain, France, Italy, The Netherlands, Belgium, Hungary, Denmark, Finland, Norway, Czech, Sweden, Austria, Poland and Switzerland) with more than 100 records in all days of 2020. RESULTS: During the COVID-19 pandemic, the sleeping pattern before and after the country-level lockdown largely differed. The subjects increased their sleep duration by an average of 11.3 to 18.6 min on weekday nights, except Denmark (4.9 min) and Finland (7.1 min). In addition, subjects form all 16 European countries delayed their sleep onset from 10.7 min (Sweden) to 29.6 min (Austria). CONCLUSION: During the COVID-19 pandemic, residents in the US and 16 European countries delayed their bedtime and slept longer than usual.

The effectiveness of a pressure injury prevention program for nursing assistants in private for-profit nursing homes: A cluster randomized controlled trial.

AIM: To examine the effectiveness of a pressure injury prevention program for private for-profit nursing homes. DESIGN: This study was a two-arm cluster randomized controlled trial. Ten private for-profit nursing homes made up the clusters. METHODS: The participants were nursing home residents who aged 60 or above regardless of whether or not having pre-existing pressure injuries and also three types of nursing home assistants who provided direct care to the residents from 10 private for-profit nursing homes. These 10 nursing homes were randomly assigned to either the experimental or the control group. There were 477 and 536 resident participants and 51 and 62 nursing assistant participants in the experimental and control groups, respectively. The residents were the study participants and the nursing assistant participants were the interveners. The experimental group had the pressure injury prevention program implemented while the control group received the usual care. The primary study outcome which was the pressure injury incidence was analysed by GEE. Significance was set at a p-value of ≤.05. The data were collected between September 2017-March 2018. RESULT: There were significant interactive effects of time and group on the incidence of pressure injuries (p = .0015) and on the skill performance of the nursing assistant participants (p < .0001). CONCLUSIONS: An evidence-based pressure injury prevention program reduced the development of the pressure injuries and improved the skill performance of the nursing assistant participants. It is highly recommended that private for-profit nursing homes with high proportion of non-professional nursing assistants and insufficient nurses adopt this program for improving the prevention care of pressure injuries. IMPACT: This research has an impact on prevention care of pressure injury in private for-profit nursing homes with high proportion non-professional nursing assistants which have the similar characteristics as the nursing homes studied in various regions and countries. TRIAL REGISTRATION: The Controlled Trial registration ID is NCT02270385.

A cluster randomized controlled trial of a simplified 5-step handwashing technique versus a conventional 7-step handwashing technique among Chinese students with intellectual disabilities.

OBJECTIVE: To compare the effects of the simplified 5-step and the conventional 7-Step hand hygiene programme in a cluster randomized controlled trial among students with intellectual disabilities. METHOD: A total of 472 Chinese students with intellectual disabilities were randomized to either simplified 5-step or conventional 7-step hand hygiene programme. Assessments included handwashing technique, cleanliness and sick leave days. RESULTS: Handwashing technique scores (g = 0.25, 95% CI [0.18, 0.32]) and hand cleanliness scores (g = 0.33, 95% CI [0.26, 0.4]) in intervention group were significantly higher than those scores in control group at 6th month post-intervention although there were significant increases in the scores within both groups. The mean number of sick leave days decreased between baseline and 10 month in both groups according to descriptive statistics. CONCLUSIONS: It is feasible and effective to adopt the simplified 5-step intervention as a standardized handwashing technique for the population group with intellectual disabilities.

Smoking and Influenza-associated Morbidity and Mortality: A Systematic Review and Meta-analysis.

BACKGROUND: Although smoking has been recognized as a risk factor for many respiratory diseases, its effects of influenza-associated morbidity and mortality remain controversial. We conducted a systematic review and meta-analysis to assess the impact of smoking on influenza-associated hospital admissions, intensive care unit (ICU) admissions, and deaths. METHODS: We searched the databases of PubMed, CINAHL, EMBASE, and the China National Knowledge Infrastructure for all observational studies published between 1 January 2000 and 30 November 2017 on ever-active/secondhand smoking and influenza-associated hospital admissions, ICU admissions, and deaths. We pooled data using random effect models. RESULTS: The initial search retrieved 7495 articles, of which 20 studies were included for systematic review, and 12 studies (eight case-control studies, two cohort studies, and two cross-sectional studies) with 18612 subjects were included in meta-analysis. The overall quality of selected studies was moderate. Ever-active smokers had higher odds of hospital admissions (odds ratio [OR] = 1.5; 95% confidence interval [CI] = 1.3, 1.7) and ICU admissions (OR 2.2; 95% CI = 1.4, 3.4) after influenza infections, as compared with never smokers. No association was observed between ever-active smoking and influenza-associated deaths. We found a positive association between secondhand smoking and influenza-associated hospital admissions, but only in children below 15 years of age. CONCLUSIONS: The literature evidence showed that smoking was consistently associated with higher risk of hospital admissions after influenza infection, but the results for ICU admissions and deaths were less conclusive because of the limited number of studies.

Determining the Optimal Number of Wearing-Days Given a Fixed Number of Accelerometers in Population-Level Study.

BACKGROUND: In research using accelerometers to measure physical activity, the number of accelerometers that can be utilized in a study and the study duration are both constrained. It means that increasing the number of accelerometer wearing days for all subjects leads to a decrease in the total number of participants the study can recruit. We used simulations to find the optimal combination of the number of wearing days and number of participant given a fixed number of accelerometer days. METHODS: Two scenarios were studied here, including estimation of population physical activity level and the association between physical activity level and a health outcome. Another similar simulation was conducted by bootstrapping the National Health and Nutrition Examination Survey (NHANES) 2003-2006 accelerometer data (n = 4,069). RESULTS: The simulation results of the first scenario showed that the error was minimized when the number of wearing days was 1 to 2. Simulation results of the second scenario showed that the optimal number of wearing days increased with the total number of accelerometer days and decreased with intra-class correlation (ICC). CONCLUSION: We developed a tool for researchers to determine the optimal combination of the number of the accelerometer wearing days and the total number of participants and showed that 1 to 2 accelerometer wearing days is optimal for estimation of population physical activity level.

Family carers' experiences of participating in a weight management programme for overweight children and adolescents with intellectual disabilities: An exploratory study.

AIM: To gain insight into the experiences of family carers participating in a weight management programme via mHealth tools for overweight children and adolescents with intellectual disabilities. BACKGROUND: Many weight reduction programs fail to show positive and sustainable impacts due to not involving parents, who are usually unavailable to attend school-based health programs. The mHealth interactive interventions were carried out in September 2015-August 2016, engaging carers to monitor and sustain their children's healthy lifestyle behaviours at home being one way to achieve this. DESIGN: Qualitative research design to conduct focus group discussion with family carers involved in a school-based weight management programme via the mHealth interventions. METHODS: An exploratory study was used to examine family carers' views of participating in a weight management programme. Focus group interviews examined the in-depth experiences of 20 family carers in providing social support and monitoring lifestyle behaviours via the mHealth interactive interventions. RESULTS: Twenty family carers were recruited and four themes emerged: (a) improving family carer-child interactions and communications; (b) gaining useful and practical health information from experts; (c) supporting each other via an mHealth platform; and (d) appreciating the collaborative effort between school personnel and family carers. Family carers stressed the usefulness of the mHealth interactive interventions in monitoring and sustaining the children's healthy lifestyle behaviours at home. CONCLUSION: The mHealth interactive interventions for increasing family carers' involvement and monitoring were well received. The findings provide new insights into using mHealth interventions in future weight management programmes involving parental participation in the home environment.

Yoga training modulates adipokines in adults with high-normal blood pressure and metabolic syndrome.

Metabolic syndrome (MetS) is associated with diabetes mellitus and cardiovascular diseases. Our previous study indicated that people with MetS showed a decrease in waist circumference and a decreasing trend in blood pressure after 1-year yoga. This study investigated the effect of yoga on MetS people with high-normal blood pressure by exploring modulations in proinflammatory adipokines (leptin, chemerin, visfatin, and plasminogen activator inhibitor-1 or PAI-1) and an anti-inflammatory adipokine (adiponectin). A total of 97 Hong Kong Chinese individuals aged 57.6 ± 9.1 years with MetS and high-normal blood pressure were randomly assigned to control (n = 45) and yoga groups (n = 52). Participants in the control group were not given any intervention but were contacted monthly to monitor their health status. Participants in the yoga group underwent a yoga training program with three 1-hour yoga sessions weekly for 1 year. The participants' sera were harvested and assessed for adipokines. Generalized estimating equation (GEE) was used to examine the interaction effect between 1-year time (pre vs post), and intervention (control vs yoga). GEE analyses revealed significant interaction effects between 1-year time and yoga intervention for the decreases in leptin and chemerin and the increase in adiponectin concentration in the sera examined. These results demonstrated that 1-year yoga training decreased proinflammatory adipokines and increased anti-inflammatory adipokine in adults with MetS and high-normal blood pressure. These findings support the beneficial role of yoga in managing MetS by favorably modulating adipokines.

Diagnosis checking of statistical analysis in RCTs indexed in PubMed.

BACKGROUND: Statistical analysis is essential for reporting of the results of randomized controlled trials (RCTs), as well as evaluating their effectiveness. However, the validity of a statistical analysis also depends on whether the assumptions of that analysis are valid. OBJECTIVE: To review all RCTs published in journals indexed in PubMed during December 2014 to provide a complete picture of how RCTs handle assumptions of statistical analysis. METHODS: We reviewed all RCTs published in December 2014 that appeared in journals indexed in PubMed using the Cochrane highly sensitive search strategy. The 2014 impact factors of the journals were used as proxies for their quality. The type of statistical analysis used and whether the assumptions of the analysis were tested were reviewed. RESULTS: In total, 451 papers were included. Of the 278 papers that reported a crude analysis for the primary outcomes, 31 (27·2%) reported whether the outcome was normally distributed. Of the 172 papers that reported an adjusted analysis for the primary outcomes, diagnosis checking was rarely conducted, with only 20%, 8·6% and 7% checked for generalized linear model, Cox proportional hazard model and multilevel model, respectively. Study characteristics (study type, drug trial, funding sources, journal type and endorsement of CONSORT guidelines) were not associated with the reporting of diagnosis checking. CONCLUSION: The diagnosis of statistical analyses in RCTs published in PubMed-indexed journals was usually absent. Journals should provide guidelines about the reporting of a diagnosis of assumptions.

The convergent validity of Actiwatch 2 and ActiGraph Link accelerometers in measuring total sleeping period, wake after sleep onset, and sleep efficiency in free-living condition.

PURPOSE: Physical activity (PA) and sleep are important to health; thus, it is important for researchers to have valid tools to measure them. Accelerometers have been proven valid for measuring PA and sleep, but only one device does this simultaneously: the ActiGraph Link (ActiGraph, LLC); however, the sleep-monitoring function has not been validated. This study aimed to evaluate the predictive power of ActiGraph Link sleep parameters against a validated accelerometer (Actiwatch 2, Phillips Respironics Mini-Mitter). METHODS: A total of 49 Hong Kong adults aged 18-64 provided valid data on both accelerometers on their non-dominant wrist for seven consecutive days. Epochs from both accelerometers were classified as either sleep or awake using seven established algorithms (Cole-Kripke, Sadeh, Sazonov, high sensitivity threshold, medium sensitivity threshold, low sensitivity threshold, and neural network model), and these data were transformed to total sleeping period, wake after sleep onset, and sleep efficiency. RESULTS: The non-zero count data for both accelerometers (331,103 observations) were strongly correlated with a Spearman correlation of 0.83 (p < 0.001). The total sleeping period was highly correlated (Spearman correlation ranged from 0.74 to 0.90) regardless of the algorithms used. All algorithms yielded insignificant difference in total sleep time measured by the two accelerometers (p > 0.05) with a negligible effect size of d < 0.2. The agreement of sleep/wake status was high for all algorithms, with accuracy ranging from 93.05 % (Sadeh's algorithm) to 96.13 % (Cole-Kripke's algorithm). CONCLUSIONS: Results showed that the sleep function of the ActiGraph Link performs similar to a validated accelerometer (Actiwatch 2) and provides an opportunity to measure both sleep and PA simultaneously.

Identification of confounder in epidemiologic data contaminated by measurement error in covariates.

BACKGROUND: Common methods for confounder identification such as directed acyclic graphs (DAGs), hypothesis testing, or a 10 % change-in-estimate (CIE) criterion for estimated associations may not be applicable due to (a) insufficient knowledge to draw a DAG and (b) when adjustment for a true confounder produces less than 10 % change in observed estimate (e.g. in presence of measurement error). METHODS: We compare previously proposed simulation-based approach for confounder identification that can be tailored to each specific study and contrast it with commonly applied methods (significance criteria with cutoff levels of p-values of 0.05 or 0.20, and CIE criterion with a cutoff of 10 %), as well as newly proposed two-stage procedure aimed at reduction of false positives (specifically, risk factors that are not confounders). The new procedure first evaluates potential for confounding by examination of correlation of covariates and applies simulated CIE criteria only if there is evidence of correlation, while rejecting a covariate as confounder otherwise. These approaches are compared in simulations studies with binary, continuous, and survival outcomes. We illustrate the application of our proposed confounder identification strategy in examining the association of exposure to mercury in relation to depression in the presence of suspected confounding by fish intake using the National Health and Nutrition Examination Survey (NHANES) 2009-2010 data. RESULTS: Our simulations showed that the simulation-determined cutoff was very sensitive to measurement error in exposure and potential confounder. The analysis of NHANES data demonstrated that if the noise-to-signal ratio (error variance in confounder/variance of confounder) is at or below 0.5, roughly 80 % of the simulated analyses adjusting for fish consumption would correctly result in a null association of mercury and depression, and only an extremely poorly measured confounder is not useful to adjust for in this setting. CONCLUSIONS: No a prior criterion developed for a specific application is guaranteed to be suitable for confounder identification in general. The customization of model-building strategies and study designs through simulations that consider the likely imperfections in the data, as well as finite-sample behavior, would constitute an important improvement on some of the currently prevailing practices in confounder identification and evaluation.

Energy intake, energy required and mortality in an older population.

OBJECTIVES: The present study evaluated the association between energy intake, energy required and mortality in older adults. DESIGN: A cohort study with a mean of 10·67 (sd 4·74) years of follow-up. Participants completed a 24 h dietary recall. Energy required per day was computed by BMR. Deaths through 2006 were identified from the National Death Index. A Cox regression was used to estimate the hazard ratios (HR) of quantiles of energy intake and energy required on all-cause and CVD mortality, adjusting for demographics, socio-economic status and co-morbidity. SETTING: The National Health and Nutrition Examination Survey (NHANES) III, 1988-1994. SUBJECTS: A total of 4846 participants aged 60 years or above were analysed. RESULTS: Within the follow-up period, there were a total of 2954 deaths (61·0 %), 51·9 % were caused by CVD. Relative to those in quartile 1 of energy intake, only quartile 4 was associated with all-cause mortality and CVD mortality with HR of 0·86 (95 % CI 0·77, 0·96, P=0·006) and 0·76 (95 % CI 0·65, 0·89, P=0·001), respectively. On the other hand, relative to those in quartile 1 of energy required, all quartiles of participants had a lower risk of all-cause mortality and CVD mortality. The interaction effects between energy intake and energy required with all-cause and CVD mortality were insignificant (P=0·70 and 0·61, respectively). CONCLUSIONS: Independent of energy required, higher energy intake was associated with lower HR of both all-cause and CVD mortality in older adults.

Substitution of SF-36 by SF-12 Among Hong Kong Chinese Older Adults: Secondary Analysis of Randomized Controlled Trials.

PURPOSE: This study aims to examine the appropriateness of substituting the Short-Form 36 (SF-36) by its shortened version (SF-12) in measuring health-related quality of life (HRQoL) in older Chinese population. METHODS: Secondary analysis of two transitional care management programs, conducted from 2009 to 2012, were analyzed (n = 1188, aged 60-97). Participants were discharged patients with respiratory disease, type 2 diabetes, cardiac disease, and renal disease, and were classified according to number of chronic diseases. SF-36 was administered at baseline and 4-week follow-up. RESULTS: Both overestimations and underestimations of HRQoL by SF-12 were found. Most domain scores of SF-36 and SF-12 were highly correlated (Spearman correlation (ρ) > 0.85), with the exception of General Health (ρ = 0.64) and Vitality subscales (ρ = 0.82). Multiple linear regression adjusted for demographic characteristics showed that the four out of eight domains of SF-36 and SF-12 were equivalent in measuring the difference across numbers of chronic diseases (all p < 0.05). Paired sample t tests in 989 (83.2 %) who completed the SF-36 survey 4 weeks after baseline showed that SF-12 overestimated the 4-week changes in most of the domains. CONCLUSIONS: The use of the Chinese version of SF-12v2 for reporting the change over time in quality of life among medical patients after hospital discharge may need to be interpreted with caution. The SF-12 tends to underestimate the difference when compared with the SF-36.

Suicidality among Hong Kong nurses: prevalence and correlates.

AIMS: The study estimates the prevalence and examines the socio-economic and psychological correlates of suicidality among professional nurses in Hong Kong. BACKGROUND: Suicide rates among middle-aged employed groups have been increasing over the past few decades. There is a concern that medical occupational groups worldwide are at elevated risk of suicide. Nonetheless there are few population-based studies of suicide dealing with working-age Asian nurses. DESIGN: The study uses a cross-sectional survey design. METHOD: Data were collected in Hong Kong over 4 weeks from October-November 2013. Statistical methods including descriptive analysis and univariate and multivariate cumulative logit modelling were used to examine the weighted prevalence rates of past-year suicidality and its associated factors in nurses. RESULTS: A total of 850 nurses participated in the study; 14·9% of participants had contemplated suicide while 2·9% had attempted suicide once or more in the past year. Women report suicidal thoughts or attempts more often than men. Religion, poor health, deliberate self-harm, depressive symptoms and poor self-perceived physical and mental health were significantly associated with nurses' suicidality. CONCLUSIONS: Nurse professionals are not immune from mental health issues. Hong Kong's local health authority should put in place a raft of suicide prevention initiatives to promote mental wellness in the profession.