Community ambulation in older adults and people with OA - a model verification using Canadian Longitudinal Study on Aging (CLSA) data.

BACKGROUND: There are health and well-being benefits of community ambulation; however, many older adults do not regularly walk outside of their home. Objectives were to estimate the associations between latent constructs related to community ambulation in older adults aged 65-85 (65+), and in adults with osteoarthritis (OA) aged 45-85. METHODS: Secondary data analysis of the comprehensive baseline and maintaining contact questionnaire data from the Canadian Longitudinal Study of Aging (CLSA) was completed. Based on a previous model of community ambulation post-stroke, structural equation modeling (SEM) was used to develop measurement and structural models for two groups: older adults 65+ and people with OA. Multi-group SEM was conducted to test measurement invariance across sex and age groups. Measurement models were developed for the following latent factors: ambulation (frequency of walking outside/week, hours walked/day, ability to walk without help, frequency and aids used in different settings); health perceptions (general health, pain frequency/intensity); timed functional mobility (gait speed, timed up-and-go, sit-to-stand, balance). Variables of depression, falls, age, sex, and fear of walking alone at night were covariates in the structural models. RESULTS: Data were used from 11,619 individuals in the 65+ group (mean age 73 years ±6, 49% female) and 5546 individuals in the OA group (mean age 67 ± 10, 60% female). The final 65+ model had a close fit with RMSEA (90% CI) = 0.018 (0.017, 0.019), CFI = 0.91, SRMR = 0.09. For the OA group, RMSEA (90% CI) = 0.021 (0.020, 0.023), CFI = 0.92, SRMR = 0.07. Health perceptions and timed functional mobility had a positive association with ambulation. Depression was associated with ambulation through negative associations with health perceptions and timed functional mobility. Multi-group SEM results reveal the measurement model was retained for males and females in the 65+ group, for males and females and for age groups (65+, < 65) in the OA group. CONCLUSIONS: The community ambulation model post-stroke was verified with adults aged 65+ and for those with OA. The models of community ambulation can be used to frame and conceptualize community ambulation research and clinical interventions.

Verification of a comprehensive framework for mobility using data from the Canadian Longitudinal Study on Aging: a structural equation modeling analysis.

BACKGROUND: Mobility within and between life spaces is fundamental for health and well-being. Our objective was to verify a comprehensive framework for mobility. METHODS: This was a cross-sectional study. We used structural equation modeling to estimate associations between latent factors with data from the Canadian Longitudinal Study on Aging for participants 65-85 years of age (65+, n = 11,667) and for adults with osteoarthritis (OA) aged 45-85 (n = 5,560). Latent factors included life space mobility, and physical, psychosocial, environmental, financial, and cognitive elements. Personal variables (age, sex, education) were covariates. RESULTS: The models demonstrated good fit (65+: CFI = 0.90, RMSEA (90% CI) = 0.025 (0.024, 0.026); OA: CFI = 0.90, RMSEA (90% CI) = 0.032 (0.031, 0.033)). In both models, better psychosocial and physical health, and being less afraid to walk after dark (observed environmental variable) were associated with greater life space mobility. Greater financial status was associated with better psychosocial and physical health. Higher education was related to better cognition and finances. Older age was associated with lower financial status, cognition, and physical health. Cognitive health was positively associated with greater mobility only in the 65 + model. Models generated were equivalent for males and females. CONCLUSIONS: Associations between determinants described in the mobility framework were verified with adults 65-85 years of age and in an OA group when all factors were considered together using SEM. These results have implications for clinicians and researchers in terms of important outcomes when assessing life space mobility; findings support interdisciplinary analyses that include evaluation of cognition, depression, anxiety, environmental factors, and community engagement, as well as physical and financial health. Public policies that influence older adults and their abilities to access communities beyond their homes need to reflect the complexity of factors that influence life space mobility at both individual and societal levels.

Chronic Liver Disease and Metabolic Comorbidities in Healthy Young Males Followed for 65 Years: The Manitoba Follow-up Study.

BACKGROUND & AIMS: The prevalence of chronic liver disease (CLD) is largely derived from cross-sectional epidemiologic surveys. The goal of this long-term, prospective study was to document the lifetime risk of developing chronic liver disease and determine the impact of common metabolic conditions associated with metabolic syndrome (MetS) on the development and outcomes of CLD. METHODS: 3,983 air force men were enrolled in the Manitoba Follow-up Study in 1948. The comprehensive database on results of routine physicals and health encounters was examined for evidence of CLD and MetS. The joint relationship between CLD and components of MetS on mortality was examined using Cox proportional hazard model. RESULTS: In 65 follow-up years, 5.2% of men developed CLD and 6.4% MetS. Hypertension was the strongest predictor of CLD (HR 2.958, 95% CI - 2.065 to 4.236, p < .0001), followed by insulin resistance /diabetes mellitus (IR/DM) (2.008, 95% CI - 1.332 to 3.027, p = .0009) and obesity (1.958, 95% CI - 1.419 to 2.703, p < .0001). Relative to men without MetS comorbidities, an increasing gradient of risk for CLD was apparent with increasing numbers of MetS components; the HR of 3.67, 5.97 and 14.3 for IR/DM, IR/DM + one component, and IR/DM + two or more components respectively. The relative risk of mortality in men with vs. without CLD was 3.33 (95% CI - 2.83 to 3.91, p < .0001) and 1.505 (95% CI - 1.31 to 1.73, p < .0001) in men with vs. without MetS. CONCLUSIONS: CLD and MetS independently increase the relative risk of mortality; the magnitude of the effect is greater in CLD.

Social determinants and spatio-temporal variation of Ischemic Heart Disease in Manitoba.

INTRODUCTION: The aim was to study any spatial and/or temporal patterns of ischemic heart disease (IHD) prevalence and measure the effects of selected social determinants on these spatial and space-time patterns. METHODS: Data were obtained from the Population Research Data Repository housed at the Manitoba Centre for Health Policy to identify persons who were diagnosed with IHD between 1995 and 2018. These persons were geocoded to 96 geographic regions of Manitoba. An area-level socioeconomic factor index (SEFI-2) and the proportion of the population who was Indigenous were calculated for each geographic region using the 2016 Canadian Census data. Associations between these factors and IHD prevalence were measured using Bayesian spatial Poisson regression models. Temporal trends and spatio-temporal trends were measured using Bayesian spatio-temporal Poisson regression models. RESULTS: Univariable models showed a significant association with increased regional Indigenous population proportion associated with a higher prevalence of IHD (RR: 0.07, 95% CredInt: (0.05, 0.10)) and for SEFI-2 (RR: 0.17, 95% CredInt: (0.11, 0.23)). Using a multivariable model, after accounting for the proportion of the population that was Indigenous, there was no evidence of an association between IHD prevalence and area-level socioeconomic factor. Spatio-temporal models showed no significant overall temporal trend in IHD prevalence, but there were significant spatially varying temporal trends within the 96 regions. CONCLUSIONS: Association between Indigenous population proportion and IHD is consistent with previous research. No significant overall temporal trend was measured. However, regions with significantly increasing trends and significantly decreasing trends in IHD prevalence were identified.

Multimorbidity in Canadians living in the community: Results from the Canadian Longitudinal Study of Aging.

OBJECTIVE: To determine the mean number of chronic diseases in Canadians aged 45 to 85 years who are living in the community, and to characterize the association of multimorbidity with age, sex, and social position. DESIGN: An analysis of data from the Canadian Longitudinal Study on Aging. The number of self-reported chronic diseases was summed, and then the mean number of chronic health problems was standardized to the 2011 Canadian population. Analyses were conducted stratified on sex, age, individual income, household income, and education level. SETTING: Canada. PARTICIPANTS: A total of 21 241 community-living Canadians aged 45 to 85 years. MAIN OUTCOME MEASURES: Overall, 31 chronic diseases (self-reported from a list) were considered, as were risk factors that were not mental health conditions or acute in nature. Age, sex, education, and household and individual incomes were also self-reported. RESULTS: Multimorbidity was common, and the mean number of chronic illnesses was 3.1. Women had a higher number of chronic illnesses than men. Those with lower income and less education had more chronic conditions. The number of chronic conditions was strongly associated with age. The mean number of conditions was 2.1 in those aged 45 to 54; 2.9 in those 55 to 64; 3.8 in those aged 65 to 74, and 4.8 in those aged 75 and older (P < .05, ANOVA [analysis of variance]). CONCLUSION: Multimorbidity is common in the Canadian population and is strongly related to age.

Life satisfaction in adults in rural and urban regions of Canada - the Canadian Longitudinal Study on Aging.

INTRODUCTION: Understanding rural-urban differences, and understanding levels of life satisfaction in rural populations, is important in planning social and healthcare services for rural populations. The objectives of this study were to determine patterns of life satisfaction in Canadian rural populations aged 45-85 years, to determine rural-urban differences in life satisfaction across a rural-urban continuum after accounting for potential confounding factors and to determine if related social and health factors of life satisfaction differ in rural and urban populations. METHODS: A secondary analysis was conducted using data from an ongoing population-based cohort study, the Canadian Longitudinal Study on Aging. A cross-sectional sample from the baseline wave of the tracking cohort was used, which was intended to be as generalizable as possible to the Canadian population. Four geographic areas were compared on a rural-urban continuum: rural, mixed (indicating some rural, but could also include some peri-urban areas), peri-urban, and urban. Life satisfaction was measured using the Satisfaction with Life Scale and dichotomized as satisfied versus dissatisfied. Other factors considered were province of residence, age, sex, education, marital status, living arrangement, household income, and chronic conditions. These factors were self-reported. Bivariate analyses using χ2 tests were conducted for categorical variables. Logistic regression models were constructed with the outcome of life satisfaction, after which a series of models were constructed, adjusting for province of residence, age, and sex, for sociodemographic factors, and for health-related factors. To report on differences in the factors associated with life satisfaction in the different areas, logistic regression models were constructed, including main effects for the variable of interest, for the variable rurality, and for the interaction term between these two variables. RESULTS: Individuals living in rural areas were more satisfied with life than their urban counterparts (odds ratio (OR)=1.23; 95% confidence interval (CI): 1.13-1.35), even after accounting for the effect of confounding sociodemographic and health-related factors (OR=1.32, 95%CI: 1.19-1.45). Those living in mixed (OR=1.30, 95%CI: 1.14-1.49) and peri-urban (OR=1.21, 95%CI: 1.07-1.36) areas also reported being more satisfied than those living in urban areas. In addition, a positive association was found between life satisfaction and age, as well as between life satisfaction and being female. A strong graded association was noted between income and life satisfaction. Most chronic conditions were associated with lower life satisfaction. Finally, no major interaction was noted between rurality and each of the previously mentioned different factors associated with life satisfaction. CONCLUSION: Rural-urban differences in life satisfaction were found, with higher levels of life satisfaction in rural populations compared to urban populations. Preventing and treating common chronic illness, and also reducing inequalities in income, may prove useful to improving life satisfaction in both rural and urban areas. Studies of life satisfaction should consider rurality as a potential confounding factor in analyses of life satisfaction within and across societies.

Differential Expression of Genes for Ubiquitin Ligases in Medulloblastoma Subtypes.

Using publically available datasets on gene expression in medulloblastoma (MB) subtypes, we selected genes for ubiquitin ligases and identified statistically those that best predicted each of the four major MB subgroups as separate disease entities. We identify a gene coding for an ubiquitin ligase, ZNRF3, whose overexpression alone can predict the WNT subgroup for 100% in the Pfister dataset. For the SHH subgroup, we identify a gene for a regulatory subunit of the protein phosphatase 2A (PP2A), PPP2R2C, as the major predictor among the E3 ligases genes. The ubiquitin and ubiquitin-like conjugation database (UUCD) lists PPP2R2C as coding for a Cullin Ring ubiquitin ligase adaptor. For group 3 MBs, the best ubiquitin ligase predictor was PPP2R2B, a gene which codes for another regulatory subunit of the PP2A holoenzyme. For group 4, the best E3 gene predictors were MID2, ZBTB18, and PPP2R2A, which codes for a third PP2A regulatory subunit. Heatmap analysis of the E3 gene data shows that expression of ten genes for ubiquitin ligases can be used to classify MBs into the four major consensus subgroups. This was illustrated by analysis of gene expression of ubiquitin ligases of the Pfister dataset and confirmed in the dataset of Cavalli. We conclude that genes for ubiquitin ligases can be used as genetic markers for MB subtypes and that the proteins coded for by these genes should be investigated as subtype specific therapeutic targets for MB.

Multimorbidity predicts functional decline in community-dwelling older adults: Prospective cohort study.

OBJECTIVE: To determine if multimorbidity is associated with functional status, and to assess if multimorbidity predicts declining functional status over a 5-year time frame, after accounting for baseline functional status and other potential confounding factors. DESIGN: Analysis of an existing population-based cohort study. SETTING: Manitoba. PARTICIPANTS: Community-dwelling adults aged 65 and older. MAIN OUTCOME MEASURES: Age, sex, education, and the Mini-Mental State Examination (MMSE) and Center for Epidemiological Studies Depression Scale (CES-D) scores were recorded for each patient. Multimorbidity was measured using a simple tally of self-reported diseases. Function was measured using the Older Americans Resources and Services scale in 1991 to 1992 and again 5 years later. Good or excellent level of function was compared with level of disability (mild or moderate or higher). Cross-sectional and prospective analyses were conducted. RESULTS: In a cross-sectional analysis, multimorbidity predicted disability. The unadjusted odds ratio (OR) (95% CI) for disability was 1.45 (1.39 to 1.52) for each additional chronic illness. In models adjusting for age, sex, education, and MMSE and CES-D scores, the adjusted OR (95% CI) was 1.35 (1.29 to 1.42) for each additional chronic illness. Multimorbidity also predicted disability 5 years later. The unadjusted OR (95% CI) was 1.31 (1.24 to 1.38). In models adjusting for age, sex, education, and MMSE and CES-D scores in addition to baseline functional status, the adjusted OR (95% CI) was 1.15 (1.09 to 1.24). CONCLUSION: Multimorbidity predicts disability in cross-sectional and prospective analyses.

Construct Validation of Three Nutrition Questions Using Health and Diet Ratings in Older Canadian Males Living in the Community.

Brief nutrition screening tools are desired for research and practice. Seniors in the Community: Risk Evaluation for Eating and Nutrition (SCREEN-II, 14 items) and the abbreviated version SCREEN-II-AB (8 items) are valid and reliable nutrition screening tools for older adults. This exploratory study used a retrospective cross-sectional design to determine the construct validity of a subset of 3 items (weight loss, appetite, and swallowing difficulty) currently on the SCREEN-II and SCREEN-II-AB tools. Secondary data on community-dwelling senior males (n = 522, mean ± SD age = 86.7 ± 3.0 years) in the Manitoba Follow-up Study (MFUS) study were available for analysis. Participants completed the mailed MFUS Nutrition Survey that included SCREEN-II items and questions pertaining to self-rated health, diet healthiness, and rating of the importance of nutrition towards successful aging as the constructs for comparison. Self-perceived health status (F = 14.7, P < 0.001), diet healthiness (ρ = 0.17, P = 0.002) and the rating of nutrition's importance to aging (ρ = 0.10, P = 0.03) were correlated with the 3-item score. Inferences were consistent with associations between these construct variables and the full SCREEN-II. Three items from SCREEN-II and SCREEN-II-AB demonstrate initial construct validity with self-perceived health status and diet healthiness ratings by older males; further exploration for criterion and predictive validity in more diverse samples is needed.

Multimorbidity, disability, and mortality in community-dwelling older adults.

OBJECTIVE: To describe factors associated with multimorbidity in community-dwelling older adults; to determine if a simple measure of multimorbidity predicts death over 5 years; and to assess if any effect of multimorbidity on mortality is independent of key covariates. DESIGN: Analysis of an existing population-based cohort study. Cox proportional hazards models were constructed for time to death. SETTING: Manitoba. PARTICIPANTS: A total of 1751 community-dwelling adults aged 65 and older were interviewed and followed for 5 years. MAIN OUTCOME MEASURES: Age, sex, marital status, living arrangement, education, Mini-Mental State Examination (MMSE) score, Center for Epidemiologic Studies Depression Scale score, and the Older Americans Resource and Services Multidimensional Functional Assessment Questionnaire score were recorded for each participant. Multimorbidity was defined based on a simple list of common health complaints and diseases, followed by an open-ended question about other problems. These were summed and the scores ranged from 0 to 16. Death and time of death were determined during the 5-year interval by death certificate, administrative data, or proxy report. RESULTS: Multimorbidity was more prevalent in women; older age groups; and those with lower educational levels, lower MMSE scores, more depressive symptoms, and higher levels of disability. Multimorbidity was a predictor of mortality in unadjusted models (hazard ratio 1.09, 95% CI 1.05 to 1.12). In models adjusting for age, sex, education, marital status, living arrangement, and Center for Epidemiologic Studies Depression Scale and MMSE scores, this effect persisted (hazard ratio 1.04, 95% CI 1.00 to 1.08). However, after adjusting for functional status, the effect of multimorbidity was no longer significant. CONCLUSION: Multimorbidity predicts 5-year mortality but the effect might be mediated by disability.

Nutritional risk in community-dwelling older men: the Manitoba follow-up study.

PURPOSE: The role of nutrition in older men's health and successful aging has been inadequately studied. We examined the relationships among nutritional risk, self-rated health, and successful aging in community-dwelling Canadian older men. METHODS: The surviving cohort of the Manitoba Follow-up Study (n=690, mean age = 86.8 years) were sent a self-administered nutrition survey in December 2007. The survey consisted of the Seniors in the Community: Risk Evaluation for Eating and Nutrition, version II (SCREEN II), a validated tool for assessing nutritional risk of cognitively intact community-living older adults, and questions about successful aging and health. RESULTS: Of the 553 surveys returned (80% response), 522 with complete SCREEN II data were included in the analysis. Forty-four percent of respondents were at high nutritional risk, 24% were at moderate risk, and 32% were at low risk. Significant relationships were found between nutritional risk and self-rated health (P<0.0001) and successful aging (P=0.008), with greater nutritional risk associated with lower self-ratings of health and successful aging. Higher use of prescription medication was related to greater nutritional risk (P=0.004). CONCLUSIONS: Nutritional screening programs for community-dwelling older men are warranted as two-thirds of the study participants were at nutritional risk. Identifying older men at nutritional risk is a critical step in the process of nutritional assessment, and subsequent nutrition interventions and follow-up are required to prevent further health decline.

Survey of fluoride levels in vended water stations.

This study sought to measure the fluoride concentration of water derived from vended water stations (VWS) and to identify its clinical implications, especially with regard to caries prevention and fluorosis. VWS and corresponding tap water samples were collected from 34 unique postal zip codes; samples were analyzed in duplicate for fluoride concentration. Average fluoride concentration in VWS water was significantly lower than that of tap water (P < 0.001). Fluoride concentration in the VWS water ranged from <0.01 ppm to 0.04 ppm, with a mean concentration of 0.02 ppm (±0.02 ppm). Patients utilizing VWS as their primary source of drinking water may not be receiving optimal caries preventive benefits; thus dietary fluoride supplementation may be indicated. Conversely, to minimize the risk of fluorosis in infants consuming reconstituted infant formula, water from a VWS may be used.

How well do obesity indices predict undiagnosed hypertension in the Persian cohort (Shahedieh) adults community population of all ages?

Background and Aims: Hypertension is the leading preventable risk factor for cardiovascular disease, chronic kidney disease and cognitive impairment, and mortality and disability worldwide. Since prevention, early detection, and treatment of blood pressure improve public health, the aim of present study was to determine the best obesity indices and estimate the optimal cut-off point for each one to predict the risk of elevated/stage 1 and undiagnosed hypertension in the population of center of Iran based on American ACC/AHA 2020 guidelines. Methods: This cross-sectional study was performed on 9715 people who enrolled in 2018 in Persian Adult Cohort in Shahedieh area of Yazd, Iran in 2018. The anthropometric indices including body mass index (BMI) and waist circumference (WC), wrist circumference, hip circumference, waist-to-hip ratio, and waist-to height ratio of individuals, were extracted. The receiver operating characteristic curve was utilized to determine the optimum cut-off point of each anthropometric index to predict hypertension stages and compare their predictive power by age-sex categories. Statistical analysis was done using SPSS version 23.0. Results: The results showed that BMI has the best predictive power to recognize the risk of elevated/stage 1 hypertension for female (area under the curve [AUC] = 0.72 and optimal cut-off = 30.10 kg/m2) and WC for male (AUC = 0.66 and optimal cut-off = 93.5 cm) in 35-45 age group. BMI had the best predictive power for the risk of undiagnosed hypertension for 35-45 years old male (AUC = 0.73 and optimal cut-off = 28.90 kg/m2) and female (AUC = 0.75 and optimal cut-off = 5.10 kg/m2), and hip circumference revealed similar predictive power for female as well (AUC = 0.75 and optimal cut-off = 112 cm). Conclusion: Based on our findings, BMI and WC, which are simple, inexpensive, and noninvasive means, are the best markers to predict the risk of elevated/stage 1 and undiagnosed hypertension in young Iranians. It shows that the approach of reducing hypertension prevalence through primary prevention, early detection, and enhancing its treatment is achievable.

Self-reported factors associated with community ambulation after stroke: The Canadian Longitudinal Study on Aging.

Community ambulation is frequently limited for people with stroke. It is, however, considered important to people with stroke. The objectives were to identify factors associated with self-reported community ambulation in Canadians aged 45+ with stroke and to identify factors associated with community ambulation specific to Canadian males and to Canadian females with stroke. Data were utilized from the Canadian Longitudinal Study on Aging Tracking Cohort. Multivariate logistic regression models were developed for community ambulation. Mean age was 68 (SE 0.5) years (45% female). In the final community ambulation model (n = 855), factors associated with being less likely to 'walk outdoors sometimes or often' included difficulty or being unable to walk 2-3 blocks (decreased endurance) vs. no difficulty. Being more likely to walk outdoors was associated with 'better weather' months and being 55-64 years of age vs 75-85. Differences were noted between the models of only males and only females. Decreased walking endurance is associated with a decreased likelihood of walking in the community-a factor that can be addressed by rehabilitation professionals and in community based programs.

Factors associated with social participation and community ambulation in people with osteoarthritis: Findings from the Canadian Longitudinal Study on Aging.

AIM: Walking in the community allows participation in meaningful activities which positively influences self-rated health and quality of life. Our objective was to identify factors associated with social participation and community ambulation in a representative sample of Canadian adults with osteoarthritis (OA). METHODS: Data were from >3800 participants in the Baseline Tracking Dataset of the Canadian Longitudinal Study on Aging with OA of the hip and/or knee. Outcomes included frequency of participation in 8 community-based activities (past year, social participation), and frequency walking outside the home (past 7 days, community ambulation). Explanatory variables (15 for social participation, 11 for community ambulation) established in previous literature were evaluated. Variables significant in univariate binary logistic regression models were entered into multivariable models. RESULTS: Frequency of social participation was greater for females, and individuals with higher levels of education. Those who were younger, dissatisfied with life, and had difficulty walking 2-3 blocks were less likely to participate. Having fewer chronic conditions, being younger, being single/widowed and being interviewed in spring/summer were associated with more frequent ambulation. Lower self-rated health, difficulty walking 2-3 blocks, pain and being female were associated with less frequent walking outside the home. CONCLUSION: Many factors influence frequency of social participation and community ambulation. The ability to walk short distances is positively associated with both outcomes. This important factor can and should be addressed clinically to improve health and quality of life in people with OA.

Life Course Predictors of Young Men Surviving to Age 90 in a Cohort Study: The Manitoba Follow-up Study.

The purpose of this study was to identify factors at various time points in life that are associated with surviving to age 90. Data from men enrolled in a cohort study since 1948 were considered in 12-year intervals. Logistic regression models were constructed with the outcome of surviving to age 90. Factors were: childhood illness, blood pressure (BP), body mass index (BMI), chronic diseases, and electrocardiogram (ECG) findings. After 1996, the Short Form-36 was added. A total of 3,976 men were born in 1928 or earlier, and hence by the end of our study window in 2018, each had the opportunity of surviving to age 90. Of these, 721 did live to beyond his 90th birthday.The factors in 1948 which predicted surviving were: lower diastolic BP, lower BMI, and not smoking. In 1960, these factors were: lower BP, lower BMI, not smoking, and no major ECG changes. In 1972, these factors were lower BP, not smoking, and fewer disease states. In 1984, these factors were lower systolic BP, not smoking, ECG changes, and fewer disease states. In 1996, the factors were fewer disease states and higher physical and mental health functioning. In 2008, only higher physical functioning predicted survival to the age of 90. In young adulthood, risk factors are important predictors of surviving to age 90; in mid-life, chronic illnesses emerge, and in later life, functional status becomes predominant.

A population-based study of the epidemiology of hepatitis C in a North American population.

BACKGROUND & AIMS: Chronic hepatitis C virus (HCV) infection is a major public health problem with approximately 3% of the world's population thought to be chronically infected. However, population-based data regarding HCV incidence rates, prevalence, residence, age, and gender distributions within North America are limited. We aimed at providing a detailed descriptive epidemiology of HCV infection in a North American population with a focus on time trends in incidence rates and prevalence of newly diagnosed HCV infection since 1991, the time when laboratory testing for HCV infections became first available. METHODS: A Research Database was developed linking records from multiple administrative sources. HCV positive residents of the Canadian province of Manitoba were identified during a twelve-year period (1991-2002). The cumulative and annual incidence rates and the prevalence of newly diagnosed HCV infection in Manitoba were examined and compared between different demographic groups and urban vs. rural residents. RESULTS: A total of 5018 HCV positive cases were identified over a 12-year period. The annual number of newly diagnosed HCV infections peaked in 1998 (59.2/100,000). On the other hand, the known prevalence of HCV continued to increase (4.6-fold during the 12-year study period) among both men and women reflecting the chronic nature of the disease. Males were 1.7 times more often infected than females. HCV infections were more common in urban centers. CONCLUSIONS: Between 1995 and 2002, there was a fairly constant trend for newly diagnosed HCV infection, ranging from approximately 500 to 600 new cases annually. Hence, with a stable population size, and a low case fatality rate, the prevalence of HCV infected persons in our population has been steadily rising. There is no evidence to suggest that the incidence of HCV infection will raise, however, the burden of chronic HCV infection will continue to increase, particularly amongst older males and those residing in urban centers.

Rural practice and the personal and educational characteristics of medical students: survey of 1269 graduates of the University of Manitoba.

OBJECTIVE: To describe the relationships between rural practice and the personal and medical education characteristics of medical students and residents. DESIGN: Cross-sectional, mailed survey. SETTING: Manitoba. PARTICIPANTS: Of 2578 physician graduates of the University of Manitoba from 1965 to 2000 who were surveyed, 1269 (49%) responded. MAIN OUTCOME MEASURES: Whether physicians had ever practised in rural settings, and their demographic characteristics and adolescent, medical school, and residency training experiences. Multivariate logistic regression models were used to determine variables jointly and independently associated with rural practice. RESULTS: Of 1269 respondents, 39% had practised in rural settings, including 58% of the 362 respondents who identified family practice as their primary career activity, and 32% of the 907 respondents whose primary activities were other than family practice. For all graduates, being male (P = .0289), having lived in a rural community (P < .0001), having attended a rural high school (P < .0001), and having rural educational experiences during medical school (P = .0068) or during postgraduate training (P < .0001) were significantly related to a greater likelihood of rural practice. In the final multivariate model, graduates of rural high schools, compared with those from urban public schools, were 1.57 times (95% CI 1.09 to 2.26) more likely to have practised in rural settings. Graduates who undertook part of their undergraduate training in rural settings were 1.34 times (95% CI 1.09 to 1.75) more likely to practise in rural locations. For both undergraduates and residents, the distance of their rural education experiences from Winnipeg and the likelihood of rural practice were directly related. For both FPs and non-FPs, being male and undertaking rural education during residency training were associated with a greater likelihood of rural practice, as was the distance of the training experience from the urban setting. For non-FPs a similar association was observed with undergraduate rural experiences. CONCLUSION: This large survey of graduates from a Canadian medical school demonstrated that attending a rural high school (P < .0001) and having rural educational exposure during medical school and residency training (P = .0068) were significantly associated with a physician practising in a rural location. That is, rural educational experiences on the continuum from high school through residency training appeared to be associated with rural practice.

Frequency of data collection and estimation of trajectories of physical functioning and their associations with survival in older men: analyses of longitudinal data from the Manitoba Follow-Up Study.

OBJECTIVE: In studies of trajectories of physical functioning among older people, the data cannot be measured continuously, but only at certain time points in prespecified cycles. We examine how data collection cycles can affect the estimation of trajectories and their associations with survival. STUDY DESIGN AND SETTING: Longitudinal data from the Manitoba Follow-Up Study (MFUS), with 12 measurements collected annually from 2004 to 2015, are analysed using a summary measures of physical functioning from the Short Form-36 questionnaire. Based on the joint models of the functioning trajectories and risk of death, we compare the estimations among models using different frequency of data collection (annually, biennially and triennially). RESULTS: Our 2004 baseline includes 964 men who were survivors from the original MFUS cohort with mean age of 84 years and range between 75 and 94 years. Results from analysis of annual data indicate that the mean physical functioning is significantly decreasing over time. Further, the rate of decline is increasing over time. The current value of physical functioning is significantly associated with the hazard of death (p<0.001), whereas the association between the change rate and mortality is marginally significant (p<0.10). Results from analysis of biennial and triennial data reveal similar trajectory patterns of physical functioning, but could not reveal the association between the change rate of physical functioning and mortality. The frequency of data collection also impacts substantially on the estimation of heterogeneity of functioning trajectory. The prediction of mortality risk obtained using annual measurements of physical functioning are better than using biennial or triennial measurements, while the predictions obtained using biennial or triennial measurements are almost equivalent. CONCLUSION: The impact of frequency of data collection depends on the shape of functional trajectories and its linking structure to survival outcome.