British Columbia's COVID-19 surveys on population experiences, action, and knowledge (SPEAK): methods and key findings from two large cross-sectional online surveys.

OBJECTIVES: To describe the methodology and key findings of British Columbia's (BC) COVID-19 SPEAK surveys, developed to understand the experiences, knowledge, and impact of the COVID-19 pandemic on British Columbians. METHODS: Two province-wide, cross-sectional, web-based population health surveys were conducted one year apart (May 2020 and April/May 2021). Questions were drawn from validated sources grounded within the social determinants of health to assess COVID-19 testing and prevention; mental and physical health; risk and protective factors; and healthcare, social, and economic impacts during the pandemic. Quota-based non-probability sampling by geography was applied to recruit a representative sample aged 18 years and older. Recruitment included strategic outreach and longitudinal follow-up of a subgroup of respondents from round one to round two. Post-collection weighting using Census data by age, sex, education, ethnicity, and geography was conducted. RESULTS: Participants included 394,382 and 188,561 British Columbians for the first and second surveys, respectively, including a longitudinal subgroup of 141,728. Key findings showed that societal impacts, both early in the pandemic and one year later, were inequitably distributed. Families with children, young adults, and people from lower socioeconomic backgrounds have been most impacted. Significant negative impacts on mental health and stress and a deterioration in protective resiliency factors were found. CONCLUSION: These population health surveys consisting of two large cross-sectional samples provided valuable insight into the impacts and experiences of British Columbians early in the pandemic and one year later. Timely, actionable data informed several high-priority public health areas during BC's response to the COVID-19 pandemic.

RéSUMé: OBJECTIFS: Décrire la méthode et les principaux constats des enquêtes SPEAK de la Colombie-Britannique sur la COVID-19, élaborées pour comprendre l'expérience des Britanno-Colombiens durant la pandémie, ainsi que leurs connaissances de la pandémie et les effets qu'elle a eus sur eux. MéTHODE: Deux enquêtes en ligne transversales sur la santé de la population ont été menées dans toute la province à un an d'intervalle (en mai 2020 et en avril-mai 2021). Les questions, qui provenaient de sources validées ancrées dans les déterminants sociaux de la santé, ont servi à évaluer le dépistage et la prévention de la COVID-19; la santé mentale et physique; les facteurs de risque et de protection; et les effets sociaux, économiques et sur les soins de santé ressentis durant la pandémie. Un échantillonnage contingentaire non probabiliste par lieu géographique a été appliqué pour recruter un échantillon représentatif de personnes de 18 ans et plus. Le recrutement a inclus une prise de contact stratégique et un suivi longitudinal auprès d'un sous-groupe de répondants entre les cycles un et deux. Après la collecte, les données ont été pondérées selon l'âge, le sexe, le niveau d'instruction, l'ethnicité et le lieu géographique à l'aide des données du Recensement. RéSULTATS: Les participants étaient 394 382 Britanno-Colombiens au cours du premier cycle de l'enquête et 188 561 au deuxième cycle, dont un sous-groupe longitudinal de 141 728 personnes. Selon les principaux constats, la répartition des effets sociétaux, tant au début de la pandémie qu'un an plus tard, a été inéquitable. Les familles avec enfants, les jeunes adultes et les personnes de statut socioéconomique plus faible ont été les plus touchés. D'importants effets nuisibles sur la santé mentale et le stress ont été constatés, ainsi qu'une détérioration des facteurs de résilience protecteurs. CONCLUSION: Ces enquêtes sur la santé de la population comprenant deux grands échantillons transversaux ont jeté un éclairage précieux sur les effets subis et les expériences vécues par les Britanno-Colombiens au début de la pandémie et un an plus tard. Ces données opportunes et exploitables ont éclairé plusieurs domaines hautement prioritaires de la santé publique durant la riposte de la Colombie-Britannique à la pandémie de COVID-19.

Chronic disease and where you live: Built and natural environment relationships with physical activity, obesity, and diabetes.

BACKGROUND: Diabetes is among the most prevalent non-communicable diseases causing significant morbidity and mortality globally. The aetiology and disease development of diabetes are influenced by genetic, lifestyle, and environmental factors. Due to an increasing number of cases each year, it is imperative to improve the understanding of modifiable environmental risk and protective factors. In this study we aimed to analyse associations between built and natural environment features and diabetes prevalence; and two major risk factors: physical activity and obesity and their mediation effects. METHODS: We analysed relationships between walkability and park availability with physical activity, obesity, and diabetes, using self-reported data from a large cross-sectional survey in British Columbia, Canada (n = 22,418). We validated results with an independent cohort (n = 11,972) in a subset of the analyses. The outcome measures included walking, moderate to vigorous physical activity (MVPA), body mass index (BMI), and diabetes. Built and natural environment features within a 1 km road network buffer around residential postal code centroids were assessed using validated indicators of walkability and park availability. We used general linear multivariable models (GLM) to examine the direct relationship between environmental features, physical activity, obesity, and diabetes respectively. Path models were developed to analyse mediation effects of physical activity and obesity on the association between environmental indicators and diabetes. The relative contribution of direct versus indirect effects was assessed. All models were adjusted for age, gender, income. ethnicity, years lived in neighbourhood and regional accessibility. RESULTS: Walkable neighbourhoods and areas with greater park availability were associated with lower rates of diabetes. There was a direct association of walkability and park availability on physical activity (highest vs. lowest quintile OR = 1.15; 95% CI: 1.00, 1.33 and OR = 1.28, 95% CI: 1.13, 1.45 respectively), obesity (highest vs. lowest quintile OR = 0.58, 95% CI: 0.49, 0.70 and OR = 0.57, 95% CI: 0.48, 0.68 respectively) and diabetes (highest vs. lowest quintile OR = 0.62, 95% CI: 0.45, 0.85, and OR = 0.63, 95% CI: 0.47, 0.84 respectively). Results were similar in the independent cohort. The associations between diabetes and walkability and park availability respectively were partly mediated by obesity (41% of total association for walkability and 53% of total association for park availability). The mediating effect of physical activity was negligible. CONCLUSION: Results support investments in walkability through active transportation and transit infrastructure. Changes in zoning and subdivision regulations governing land use actions are required to enable compact mixed-use environments with access to parks and high quality transit service. Future studies including cost-benefit analyses of health-related economic impacts of such investments can contribute to evidence-based decisions for healthier cities.

Community design and hypertension: Walkability and park access relationships with cardiovascular health.

BACKGROUND: There is an increased literature focusing on the role of the built and natural environments in preventing hypertension. However, very few studies have quantitively analyzed specific pathways through which urban form affects blood pressure levels. OBJECTIVES: To examine how features of the built and natural environments relate to hypertension and the mediating role of transportation and leisure walking and body mass index in this relationship. METHODS: We examined the association between neighbourhood walkability and park availability with hypertension through generalized linear models in two independent population cohorts. One Cohort was 22,418 adults (My Health My Community) and the other cohort was 11,972 adults (BC Generations Project). We employed a path analysis modelling approach to explore the presence and significance of mediating factors that may contribute to any association between walkability or park availability and hypertension. This study intentionally employed walkability measures enforced through municipal zoning and subdivision regulations legally underpinned by health, safety, and welfare. All models were adjusted for socioeconomic and other characteristics where data were available. RESULTS: Our analysis of two population-based Canadian cohorts consistently found that higher levels of walkability and park accessibility were both associated with significantly lower odds of self-reported hypertension, especially for lower income individuals. Mediation analysis showed that obesity accounted for 50% and 52.9% of the total effect of walkability and park accessibility on hypertension, respectively. DISCUSSION: We suggest an integrated population health approach that considers multimorbidity as a result of exposure to car-dependent areas and the lack of green spaces. Longitudinal research is needed to document causal effects of built and natural environments on hypertension.

Routine HIV testing in acute care hospitals: Changing practice to curb a local HIV epidemic in Vancouver, BC.

Early treatment of HIV infection increases life expectancy and reduces infectivity; however, delayed HIV diagnosis remains common. Implementation and sustainability of hospital-based routine HIV testing in Vancouver, British Columbia, was evaluated to address a local HIV epidemic by facilitating earlier diagnosis and treatment. Public health issued a recommendation in 2011 to offer HIV testing to all patients presenting to three Vancouver hospitals as part of routine care, including all patients admitted to medical/surgical units with expansion to emergency departments (ED). We evaluated acceptability, feasibility, and effectiveness from 2011 to 2014 and continued monitoring through 2016 for sustainability. Between October 2011-December 2016, 114,803 HIV tests were administered at the three hospitals; an 11-fold increase following implementation of routine testing. The rate of testing was sustained and remained high through 2018. Of those tested, 151 patients were diagnosed with HIV for a testing yield of 0.13%. Review of 12,996 charts demonstrated 4935/5876 (96·9%) of admitted patients agreed to have an HIV test when offered. People diagnosed in hospital were significantly more likely to be diagnosed with acute stage (aOR 1·96, 95% CI 1·19, 3·23) infection, particularly those diagnosed in the ED. This study provides practice-based evidence of the feasibility, acceptability, and effectiveness of implementing a recommendation for routine HIV testing among inpatient and emergency department admissions, as well as the ability to normalize and sustain this change. Routine hospital-based HIV testing can increase diagnoses of acute HIV infection and facilitate earlier initiation of antiretroviral treatment.

Chlamydia trachomatis epidemiology in Canadians of Chinese ethnicity: a population-based study.

OBJECTIVES: To compare the rates of Chlamydia trachomatis infection between those of Chinese ethnicity and non-Chinese ethnicity in a large Canadian urban setting. METHODS: We examined rates of Chlamydia among residents of Vancouver and Richmond, Canada, by Chinese and non-Chinese ethnicity, from 2006 to 2010. We stratified cases by age group, sex and ethnicity. We analyzed 12,555 cases of Chlamydia from 2006 to 2010. RESULTS: The overall rate of Chlamydia was 276 per 100,000 per year. Chlamydia rates were 236 per 100,000 among those of Chinese ethnicity and 338 per 100,000 among non-Chinese. While overall rates among individuals of Chinese ethnicity were lower, rates among older Chinese women were significantly higher than among their non-Chinese counterparts. CONCLUSIONS: Physicians serving patients of Chinese ethnicity should be aware that rates among Chinese-Canadians are substantial, with rates among older women higher than among non-Chinese women, and they should consider this when screening for sexually transmitted infections in this population. Further research is needed to elucidate why this is the case.

Use of a web forum and an online questionnaire in the detection and investigation of an outbreak.

A campylobacteriosis outbreak investigation provides relevant examples of how two web-based technologies were used in an outbreak setting and potential reasons for their usefulness. A web forum aided in outbreak detection and provided contextual insights for hypothesis generation and questionnaire development. An online questionnaire achieved a high response rate and enabled rapid preliminary data analysis that allowed for a targeted environmental investigation. The usefulness of these tools may in part be attributed to the existence of an internet savvy, close-knit community. Given the right population, public health officials should consider web-based technologies, including web fora and online questionnaires as valuable tools in public health investigations.

Equity in access to total joint replacement of the hip and knee in England: cross sectional study.

OBJECTIVE: To explore geographical and sociodemographic factors associated with variation in equity in access to total hip and knee replacement surgery. DESIGN: Combining small area estimates of need and provision to explore equity in access to care. SETTING: English census wards. SUBJECTS: Patients throughout England who needed total hip or knee replacement and numbers who received surgery. MAIN OUTCOME MEASURES: Predicted rates of need (derived from the Somerset and Avon Survey of Health and English Longitudinal Study of Ageing) and provision (derived from the hospital episode statistics database). Equity rate ratios comparing rates of provision relative to need by sociodemographic, hospital, and distance variables. RESULTS: For both operations there was an "n" shaped curve by age. Compared with people aged 50-59, those aged 60-84 got more provision relative to need, while those aged >or=85 received less total hip replacement (adjusted rate ratio 0.68, 95% confidence interval 0.65 to 0.72) and less total knee replacement (0.87, 0.82 to 0.93). Compared with women, men received more provision relative to need for total hip replacement (1.08, 1.05 to 1.10) and total knee replacement (1.31, 1.28 to 1.34). Compared with the least deprived, residents in the most deprived areas got less provision relative to need for total hip replacement (0.31, 0.30 to 0.33) and total knee replacement (0.33, 0.31 to 0.34). For total knee replacement, those in urban areas got higher provision relative to need, but for total hip replacement it was highest in villages/isolated areas. For total knee replacement, patients living in non-white areas received more provision relative to need (1.04, 1.00 to 1.07) than those in predominantly white areas, but for total hip replacement there was no effect. Adjustment for hospital characteristics did not attenuate the effects. CONCLUSIONS: There is evidence of inequity in access to total hip and total knee replacement surgery by age, sex, deprivation, rurality, and ethnicity. Adjustment for hospital and distance did not attenuate these effects. Policy makers should examine factors at the level of patients or primary care to understand the determinants of inequitable provision.

Modeling the need for hip and knee replacement surgery. Part 2. Incorporating census data to provide small-area predictions for need with uncertainty bounds.

OBJECTIVE: To develop methods to produce small-area estimates of need for hip and knee replacement surgery to inform local health service planning. METHODS: Multilevel Poisson regression modeling was used to estimate rates of need for hip/knee replacement by age, sex, deprivation, rurality, and ethnic mix using a nationally representative population-based survey (the English Longitudinal Study of Ageing, n = 11,392 people age > or =50 years). Estimates of need from the regression model were then combined with stratified census population counts to produce small-area predictions of need. Uncertainty in the predictions was obtained by taking a Bayesian simulation-based approach using WinBUGS software. This allows correlations in parameter estimates to be appropriately incorporated in the credible intervals for the small-area predictions. RESULTS: Small-area estimates of need for hip/knee replacement have been produced for wards and districts in England. Rates of need are adjusted for the sociodemographic characteristics of an area and include 95% credible intervals. Need for hip/knee replacement varies geographically, dependant on the sociodemographic characteristics of an area. CONCLUSION: For the first time, small-area estimates of need for hip/knee replacement surgery have been produced together with estimates of uncertainty to inform local health planning. The methodologic approach described here could be reproduced in other countries and for other disease indicators. Further research is required to combine small-area estimates of need with provision to determine whether there is equitable access to care.

Modeling the need for hip and knee replacement surgery. Part 1. A two-stage cross-cohort approach.

OBJECTIVE: To explore inequalities in the need for hip/knee replacement surgery using a 2-stage cross-cohort approach. METHODS: In the first stage, a small-area population-based survey, the Somerset and Avon Survey of Health, was used to provide a high-quality measure of need for hip/knee replacement using the New Zealand (NZ) score. Receiver operating characteristic curve analyses were used to validate a simplified NZ score, excluding information from clinical examination. In the second stage, a nationally representative population-based survey, the English Longitudinal Study of Ageing, was used to explore inequalities in need for hip/knee replacement using the simplified NZ score. Multilevel Poisson regression modeling was used to estimate rates of need for surgery. Exposures considered were age, sex, social class, ethnicity, obesity, Index of Multiple Deprivation 2004 deprivation quintiles, rurality, and ethnic mix of area. RESULTS: Rates of need for hip/knee replacement increase with age and are lower in men than in women (rate ratio [RR] 0.7, 95% confidence interval [95% CI] 0.6-0.9 for hips; RR 0.8, 95% CI 0.7-1.0 for knees). Those of lowest social class have greater need. Need was greatest for people living in more deprived areas. Individual ethnic group did not predict the need for surgery. For hip replacement, there was no rurality effect; for knee replacement, those in town and fringe areas had greater need. Obesity was a strong predictor of need for surgery (RR 2.3, 95% CI 1.9-2.8 for hips; RR 2.4, 95% CI 2.0-2.8 for knees). CONCLUSION: This study provides evidence of greater variations of inequalities in need for hip/knee replacement than previous studies. Further research should explore geographic variation and produce small-area estimates of need to inform local health planning. It is important to complement data on need with willingness to undergo surgery.

Geographical variation in the provision of elective primary hip and knee replacement: the role of socio-demographic, hospital and distance variables.

BACKGROUND: To explore inequalities in the provision of hip/knee replacement surgery and produce small-area estimates of provision to inform local health planning. METHODS: Hospital Episode Statistics were used to explore inequalities in the provision of primary hip/knee operations in English NHS hospitals in 2002. Multilevel Poisson regression modelling was used to estimate rates of surgical provision by socio-demographic, hospital and distance variables. GIS software was used to estimate road travel times and create hospital catchment areas. RESULTS: Rates of joint replacement increased with age before falling in those aged 80+. Women received more operations than men. People living in the most deprived areas obtained fewer hip, but more knee operations. Those in urban areas received less hip surgery, but there was no association for knee replacement. Controlling for hospital and distance measures did not attenuate the effects. Geographical variation across districts was observed with some districts showing inequality in socio-demographic factors, whereas others showed none at all. CONCLUSIONS: This study found evidence of inequalities in the provision of joint replacement surgery. However, before we can conclude that there is inequity in receipts of healthcare, future research must consider whether these patterns are explained by variations in need across socio-demographic groups.

Large community outbreak of Streptococcus pneumoniae serotype 5 invasive infection in an impoverished, urban population.

BACKGROUND: Streptococcus pneumoniae is a common cause of sporadic invasive infections, but outbreaks of invasive pneumococcal disease are infrequent. In August 2006, a sudden increase in the number of patients presenting with invasive pneumococcal disease was noted at St. Paul's Hospital (Vancouver, Canada). Most patients with severe disease resided in an area referred to as the Downtown Eastside, a neighborhood known for its high rates of poverty and illicit drug use. METHODS: Prospective, laboratory-based surveillance for invasive pneumococcal disease was initiated, including on-site serotyping of S. pneumoniae isolates. A vaccination campaign using 23-valent polysaccharide pneumococcal vaccine was launched in the Downtown Eastside. Multiple logistic regression was used to examine the association of sociodemographic variables and medical risk factors with S. pneumoniae serotype status. RESULTS: A single S. pneumoniae serotype (serotype 5) was responsible for 78% of invasive pneumococcal disease cases (137 of 175 cases) during the outbreak period of August 2006-July 2007. The outbreak strain, although fully susceptible to penicillin, caused significant morbidity and placed considerable strain on the acute care system within the Vancouver Coastal Health region. Crack cocaine use was found to be the main independent risk factor associated with invasive pneumococcal disease due to S. pneumoniae serotype 5 (odds ratio, 12.4; 95% confidence interval, 2.22-69.5). CONCLUSIONS: A targeted vaccination campaign using polysaccharide pneumococcal vaccine appeared to help control this outbreak. In urban centers with high rates of illicit drug use, vaccination strategies for preventing invasive pneumococcal disease may need to be refined to include individuals who use crack cocaine.

Nonlinear growth generates age changes in the moments of the frequency distribution: the example of height in puberty.

Higher moments of the frequency distribution of child height and weight change with age, particularly during puberty, though why is not known. Our aims were to confirm that height skewness and kurtosis change with age during puberty, to devise a model to explain why, and to test the model by analyzing the data longitudinally. Heights of 3245 Christ's Hospital School boys born during 1927-1956 were measured twice termly from 9 to 20 years (n=129508). Treating the data as independent, the mean, standard deviation (SD), skewness, and kurtosis were calculated in 40 age groups and plotted as functions of age t. The data were also analyzed longitudinally using the nonlinear random-effects growth model H(t)=h(t-epsilon )+alpha, with H(t) the cross-sectional data, h(t) the individual mean curve, and epsilon and alpha subject-specific random effects reflecting variability in age and height at peak height velocity (PHV). Mean height increased monotonically with age, while the SD, skewness, and kurtosis changed cyclically with, respectively, 1, 2, and 3 turning points. Surprisingly, their age curves corresponded closely in shape to the first, second, and third derivatives of the mean height curve. The growth model expanded as a Taylor series in epsilon predicted such a pattern, and the longitudinal analysis showed that adjusting for age at PHV on a multiplicative scale largely removed the trends in the higher moments. A nonlinear growth process where subjects grow at different rates, such as in puberty, generates cyclical changes in the higher moments of the frequency distribution.

Timing of puberty determines serum insulin-like growth factor-I in late adulthood.

CONTEXT: IGFs may play an important role in disease etiology, especially cancer. Changes in diet can alter acute levels, but little is known about life course influences on IGF levels. OBJECTIVE: The objective of the study was to examine the association between timing of puberty and adulthood serum IGFs (IGF-I and IGF binding protein-3). DESIGN: This was a retrospective cohort study. SETTING: Male pupils who attended a single school in Southern England were part of the study. PARTICIPANTS: Participants in the study were a cohort of 1028 men born between 1927 and 1956 with anthropometric measures between 9 and 18 yr and adulthood serum IGF levels. MAIN OUTCOME MEASURE: The study measured serum IGF-I and IGF binding protein-3 at mean age 63 yr. RESULTS: Age at peak height velocity (APHV) was inversely associated with adult IGF-I levels. IGF-I decreased by 3.7 ng/ml (95% confidence interval 1.0-6.4, P = 0.007) for each sd increase in APHV. Prepubertal childhood height and body mass index were both inversely associated with APHV (P trend < 0.001). APHV was positively associated with adult height and inversely associated with adult body mass index. Adjustment for childhood, adult anthropometry, and other lifestyle factors did not substantially alter the association between APHV and adult IGF-I. CONCLUSIONS: This is the first study to document an association between timing of puberty and adult IGF-I levels. A better understanding of life course determinants of the IGF system may provide new insights into disease etiology and primary prevention.

Association of body mass index measured in childhood, adolescence, and young adulthood with risk of ischemic heart disease and stroke: findings from 3 historical cohort studies.

BACKGROUND: It is unclear whether early life body mass index (BMI; in kg/m(2)) is associated with adult cardiovascular disease. OBJECTIVE: The objective was to assess the association of early life BMI with the risk of ischemic heart disease (IHD) and stroke. DESIGN: The association between early life BMI and risk of adult mortality from IHD and stroke was assessed in 3 historical cohort studies in which height and weight had been assessed by using standard procedures. Participants were traced and linked to national mortality data. Participants in the 3 cohorts were born between 1922 and 1937, 1927 and 1956, and 1928 and 1950 and were aged 2-15, 9-18, and 16-22 y, respectively, at the time of assessment of their height and weight. RESULTS: Participants in all 3 cohorts had mean BMIs similar to those reported for contemporary children and young adults, but fewer of the cohort participants were overweight or obese. BMI was not associated with future risk of IHD or stroke in any cohort. The pooled (all 3 cohorts) adjusted hazard ratio per SD of early life BMI was 1.09 (95% CI: 1.01, 1.19) for IHD and 0.94 (95% CI: 0.82, 1.08) for stroke. The pooled hazard ratio of IHD when participants who were overweight or obese for their age were compared with all other participants was 1.34 (95% CI: 0.95, 1.91), and no association was found between overweight or obesity and stroke risk. The effects of BMI did not vary by cohort or by age. CONCLUSION: These results do not provide strong evidence that being overweight or obese in childhood is associated with future cardiovascular disease risk.