Global country-level estimates of associations between adult height and the distribution of income.

OBJECTIVES: This article presents the first estimates of global associations between adult height and the distribution of income, and considers the roles of regional heterogeneity, heterogeneity across low- and high-income countries, and of infant mortality as a potential mediator. METHODS: Linear parametric and semiparametric regressions predicting mean height and sexual dimorphism in height are estimated using data on one cohort born in 1996 with height measured in 2016. Measurement error in income inequality is addressed using an instrumental variables method. RESULTS: Across countries higher income per capita is strongly associated with higher mean height, and higher income inequality is associated with lower mean height after holding mean income constant. These relationships vary with mean income: at low incomes, higher mean income strongly predicts greater height but income inequality has no statistically significant effect, whereas for high-income countries, only higher income inequality predicts lower height, and only in Europe. Sexual dimorphism in height is positively associated with mean income at low incomes, but it is not related to income inequality. CONCLUSIONS: Controlling for income inequality has modest effects on a positive height-income gradient. Greater inequality predicts lower height after holding income per capita constant, suggesting that mean height should be used with caution as a proxy for standard of living in some contexts. The extent to which these associations reflect causality running from economic conditions to height cannot be determined from these results.

Economic instruments for obesity prevention: results of a scoping review and modified Delphi survey.

BACKGROUND: Comprehensive, multi-level approaches are required to address obesity. One important target for intervention is the economic domain. The purpose of this study was to synthesize existing evidence regarding the impact of economic policies targeting obesity and its causal behaviours (diet, physical activity), and to make specific recommendations for the Canadian context. METHODS: Arksey and O'Malley's (2005) methodological framework for conducting scoping reviews was adopted for this study and this consisted of two phases: 1) a structured literature search and review, and 2) consultation with experts in the research field through a Delphi survey and an in-person expert panel meeting in April 2010. RESULTS: Two key findings from the scoping review included 1) consistent evidence that weight outcomes are responsive to food and beverage prices. The debate on the use of food taxes and subsidies to address obesity should now shift to how best to address practical issues in designing such policies; and 2) very few studies have examined the impact of economic instruments to promote physical activity and clear policy recommendations cannot be made at this time. Delphi survey findings emphasised the relatively modest impact any specific economic instrument would have on obesity independently. Based on empirical evidence and expert opinion, three recommendations were supported. First, to create and implement an effective health filter to review new and current agricultural polices to reduce the possibility that such policies have a deleterious impact on population rates of obesity. Second, to implement a caloric sweetened beverage tax. Third, to examine how to implement fruit and vegetable subsidies targeted at children and low income households. CONCLUSIONS: In terms of economic interventions, shifting from empirical evidence to policy recommendation remains challenging. Overall, the evidence is not sufficiently strong to provide clear policy direction. Additionally, the nature of the experiments needed to provide definitive evidence supporting certain policy directions is likely to be complex and potentially unfeasible. However, these are not reasons to take no action. It is likely that policies need to be implemented in the face of an incomplete evidence base.

Regulating Opioid Supply Through Insurance Coverage.

Responding to an opioid crisis in Canada, policy makers have implemented supply-side interventions seldom used in the US, regulating insurance reimbursement to discourage the prescribing of specified opioids. Using national databases of all opioids dispensed through provincial pharmaceutical programs and of opioid hospitalizations from January 2006 through March 2017, we found that requiring physicians to obtain prior authorization for patients to receive reimbursement for OxyContin prescriptions substantially reduced OxyContin fills, particularly among opioid-naive patients; it also reduced overall opioid prescriptions, suggesting limited substitution. "Grandfathering" OxyNeo (an abuse-resistant OxyContin variant), allowing previous OxyContin patients to obtain OxyNeo, increased OxyNeo fills but had no detectable effect on total opioid prescriptions, which points to substantial opioid substitution among chronic users of prescription opioids. We found no effects of regulatory changes on opioid-related hospitalizations. These results suggest that restrictions on pharmaceutical formularies can reduce fills of targeted opioids with the additional benefit of altering treatment of opioid-naive and other patients differently. Canadian policy makers may wish to extend such regulations to more provincial formularies and private insurers, and policy makers in the US and elsewhere could fruitfully follow suit.

Associations between access to food stores and adolescent body mass index.

BACKGROUND: Environmental factors such as the availability of local-area food stores may be important contributors to the increasing rate of obesity among U.S. adolescents. METHODS: Repeated cross-sections of individual-level data on adolescents drawn from the Monitoring the Future surveys linked by geocode identifiers to data on food store availability were used to examine associations between adolescent weight and the availability of four types of grocery food stores that include chain supermarkets, nonchain supermarkets, convenience stores, and other grocery stores, holding constant a variety of other individual- and neighborhood-level influences. RESULTS: Increased availability of chain supermarkets was statistically significantly associated with lower adolescent Body Mass Index (BMI) and overweight and that greater availability of convenience stores was statistically significantly associated with higher BMI and overweight. The association between supermarket availability and weight was larger for African-American students compared to white or Hispanic students and larger for students in households in which the mother worked full time. CONCLUSIONS: Economic and urban planning land use policies which increase the availability of chain supermarkets may have beneficial effects on youths' weight outcomes.

Long-Term Effects of Tobacco Prices Faced by Adolescents.

Tobacco taxes in Canada varied markedly across time and across regions in the early 1990s. We exploit this variation to estimate the long reach of prices faced in adolescence on smoking behavior roughly a decade later in early to mid-adulthood. Results from a variety of econometric approaches suggest that there is a small but detectable long-run effect of price faced during adolescence. A 10% increase in prices faced during adolescence, holding contemporaneous prices constant, leads to roughly a 1% reduction in adult smoking propensity and intensity. The results are somewhat sensitive to specification and to how price during adolescence is measured.

Choices, beliefs, and infectious disease dynamics.

A dynamic model of risky behavior in the midst of an epidemic is discussed. The key result is that pessimistic expectations over the future of the epidemic induce more current risky behavior. Numerical simulation of equilibrium epidemics shows that this effect can accelerate spread of the disease in an epidemic's early stages and that the effect of policy interventions, such as preventative vaccines, may depend on whether the intervention was anticipated.

An empirical analysis of milk addiction.

We show the estimable rational addiction model tends to yield spurious evidence in favor of the rational addiction hypothesis when aggregate data are used. Direct application of the canonical model yields results seemingly indicative that non-addictive commodities such as milk, eggs, and oranges are rationally addictive. Monte Carlo simulation demonstrates that such results are likely to obtain whenever the commodity under scrutiny exhibits high serial correlation, or when even a small amount of the variation in prices is endogenous, or when overidentified instrumental variables estimators are used, or when commonly imposed restrictions are employed. We conclude that time-series data will often be insufficient to differentiate rational addiction from serial correlation in the consumption series.

Does minimum pricing reduce alcohol consumption? The experience of a Canadian province.

AIMS: Minimum alcohol prices in British Columbia have been adjusted intermittently over the past 20 years. The present study estimates impacts of these adjustments on alcohol consumption. DESIGN: Time-series and longitudinal models of aggregate alcohol consumption with price and other economic data as independent variables. SETTING: British Columbia (BC), Canada. PARTICIPANTS: The population of British Columbia, Canada, aged 15 years and over. MEASUREMENTS: Data on alcohol prices and sales for different beverages were provided by the BC Liquor Distribution Branch for 1989-2010. Data on household income were sourced from Statistics Canada. FINDINGS: Longitudinal estimates suggest that a 10% increase in the minimum price of an alcoholic beverage reduced its consumption relative to other beverages by 16.1% (P < 0.001). Time-series estimates indicate that a 10% increase in minimum prices reduced consumption of spirits and liqueurs by 6.8% (P = 0.004), wine by 8.9% (P = 0.033), alcoholic sodas and ciders by 13.9% (P = 0.067), beer by 1.5% (P = 0.043) and all alcoholic drinks by 3.4% (P = 0.007). CONCLUSIONS: Increases in minimum prices of alcoholic beverages can substantially reduce alcohol consumption.

Effect of large-scale social interactions on body weight.

I estimate models of endogenous social interactions in body weight at the county and state levels. The results show that dispersion in body weight across time and space in the U.S. is not clearly excessive, and that much of this variation can be attributed to observable individual and regional characteristics. Models exploiting variants of methods proposed by Glaeser et al. (2003), fixed effects, instrumental variable and split-sample instrumental variable methods to address endogeneity suggest that there are not large social multipliers on body weight outcomes. The evidence suggests there may be small multipliers on BMI, obesity, and morbid obesity. There is no evidence that underweight is subject to a social multiplier. The results are sensitive to specification.

Examining the association between socioeconomic position and body mass index in 1978 and 2005 among Canadian working-age women and men.

OBJECTIVES: We examined the association between socioeconomic position (SEP) and body mass index (BMI) among Canadian men and women in 1978 and 2005. We examined both the average SEP-BMI association, and variation in this association across the distribution of BMI. METHODS: We analysed data from two nationally representative surveys containing measured height and weight data: the Canada Health Survey (1978) and the Canadian Community Health Survey (2005). Ordinary least squares and quantile regression were used to examine average and distributional SEP-BMI associations, respectively, for each survey. RESULTS: Education was inversely associated with BMI for men and women at both time points, and there was no evidence of narrowing between 1978 and 2005. This association was stronger for women than men, and was particularly strong for heavier women. Education and income related differently to BMI. CONCLUSIONS: The SEP-BMI association in Canada is complex, showing variation by gender, by aspect of SEP, across the BMI distribution, and at different time points. The association departs from the more consistent social gradient in health, thereby challenging our view of BMI as a typical health issue.

Current practice and tolerance for risk in performing procedural sedation and analgesia on children who have not met fasting guidelines: a Canadian survey using a stated preference discrete choice experiment.

OBJECTIVES: The objectives were to explore the tolerance of pediatric emergency medicine (PEM) physicians for risk in choosing when to perform procedural sedation and analgesia (PSA) and to describe adherence to preprocedural fasting guidelines and factors affecting the physicians' decisions. METHODS: A survey of Canadian PEM physicians who perform PSA was conducted. Respondents were asked about their PSA practices. Risk tolerance was assessed using an economics-based stated preference elicitation method called a discrete choice experiment (DCE). Using a hypothetical clinical situation of a healthy child needing PSA, three fasting scenarios (ingestion of full meal < 2 hours ago, full meal between 2 and 4 hours ago, liquids less than 1 hour ago) were created. For each fasting scenario, 16-choice questions with varying numeric risks of major and minor adverse events were presented and respondents were asked whether they would administer PSA now or wait for guidelines to be met. In this exploratory study, choice data were analyzed using multivariate regression analysis, and preliminary inferential statistics are presented. RESULTS: A total of 114 (63.6%) completed surveys were returned. Respondents were 54% male, were in practice for a median of 6-10 years, and reported following fasting guidelines 53% of the time. Most had institutional fasting policies (70%), used ketamine (in 78% of PSA by 95% of users), and identified patient variables (prolonged pain, parental concern) as more important than environmental variables (patient flow, use of resources) in deciding when to administer PSA. Both major and minor risks of adverse events affected the choice of whether to do immediate PSA or wait until fasting guidelines were met. A 0.1-percentage-point increase in the probability of a major adverse event reduced physician likelihood of performing immediate PSA before meeting fasting guidelines by 17.6 percentage points. In comparison, a 10-percentage-point increase in the probability of a minor adverse event reduced physician likelihood of performing immediate PSA by 17.2%. Respondents were less likely to perform PSA immediately if a child had a full meal < 2 hours ago versus 2-4 hours ago or liquids < 1 hour ago. Sex, highest level of postgraduate training, frequency of performing PSA, and experience with a prior adverse event did not affect the choice to do immediate PSA. Years in practice affected the decision, with those in practice for 6-10 years more likely to perform immediate PSA than those in practice for shorter or longer. Those who reported having an institutional fasting policy were less likely to perform immediate PSA. CONCLUSIONS: These results suggest that fasting guidelines are not strictly adhered to in Canadian pediatric emergency departments (EDs) currently, and there is some willingness of physicians to change their sedation practice in light of evidence from hypothetical surveillance data about risks. On the other hand, some physicians suggest that they will follow guidelines regardless of how low the estimated risk is from surveillance data. An understanding of how physicians respond to evidence about small risks and how the information is best understood by this population is interesting for knowledge translation if evidence-based practice guidelines for procedural sedation in the ED are developed in the future.

Access to fast food and food prices: relationship with fruit and vegetable consumption and overweight among adolescents.

We examine the extent to which food prices and restaurant outlet density are associated with adolescent fruit and vegetable consumption, body mass index (BMI), and the probability of overweight. We use repeated cross-sections of individual-level data on adolescents from the Monitoring the Future Surveys from 1997 to 2003 combined with fast food and fruit and vegetable prices obtained from the American Chamber of Commerce Researchers Association and fast food and full-service restaurant outlet density measures obtained from Dun & Bradstreet. The results suggest that the price of a fast food meal is an important determinant of adolescents' body weight and eating habits: a 10% increase in the price of a fast food meal leads to a 3.0% increase in the probability of frequent fruit and vegetable consumption, a 0.4% decrease in BMI, and a 5.9% decrease in probability of overweight. The price of fruits and vegetables and restaurant outlet density are less important determinants, although these variables typically have the expected sign and are often statistically associated with our outcome measures. Despite these findings, changes in all observed economic and socio-demographic characteristics together only explain roughly one-quarter of the change in mean BMI and one-fifth of the change in overweight over the 1997-2003 sampling period.

Schooling, cognitive ability and health.

A large literature documents a strong correlation between health and educational outcomes. In this paper we investigate the role of cognitive ability in the health-education nexus. Using NLSY data, we show that one standard deviation increase in cognitive ability is associated with roughly the same increase in health as two years of schooling and that cognitive ability accounts for roughly one quarter of the association between schooling and health. Both schooling and ability are strongly associated with health at low levels but less related or unrelated at high levels. Estimates treating schooling as endogenous to health suggest that much of the correlation between schooling and health is attributable to unobserved heterogeneity; the causal effect of schooling on health is large only for respondents with low levels of schooling and low cognitive ability. An implication is that policies which increase schooling will only increase health to the extent that they increase the education of poorly-educated individuals. Subsidies to college education, for example, are unlikely to increase population health.

Disentangling the effects of morbidity and life expectancy on labor market outcomes.

Using a unique longitudinal dataset tracking the experiences of patients diagnosed with HIV+ disease, this paper develops and estimates a model capable of recovering the effect of revisions in life expectancy on labor market outcomes. The data allow us to estimate the effect of changes in health status (as objectively measured by CD4 counts) and the impact of learning that one is HIV+, which we interpret as a negative shock to life expectancy. Both parametric and distribution-free models robustly indicate that decreases in health have little effect on labor demand but decrease probability of employment. We conclude that, in this sample, negative association between income and health is attributable mostly to the effect of altered incentives induced by changes in life expectancy.

The changing direct costs of medical care for patients with HIV/AIDS, 1995-2001.

BACKGROUND: Determining the direct cost of providing medical care to patients with HIV/AIDS is important for both short-term and long-term decision-making and for appropriate resource allocation. We aimed to categorize and measure the direct costs of medical care provided to the entire HIV-positive population receiving care in southern Alberta between 1995 and 2001. METHODS: We collected all patient-specific direct costs including the cost of pharmaceutical drugs (HIV and non-HIV drugs), outpatient care (including physician costs and laboratory testing), inpatient (in-hospital) care and home care (acute, long-term, palliative) from primary sources for all patients between April 1995 and April 2001. We determined cost per patient per month (PPPM) adjusted to 2001 Canadian dollars. RESULTS: Since 1995, the direct cost of providing medical care to patients with HIV/AIDS has increased primarily as a result of increased antiretroviral drug costs both in absolute and in PPPM terms. Mean PPPM expenditures increased from 655 Canadian dollars in 1995/96, that is, before the use of highly active antiretroviral therapy (HAART), to 1036 Canadian dollars in 1997/98 when HAART was widely used. During the following 3 years, mean overall PPPM costs remained stable. Antiretroviral drugs accounted for 30% (198 Canadian dollars PPPM) of the total cost in 1995/96 increasing to 69% (775 Canadian dollars PPPM) in 2000/01. Inpatient, outpatient and home care costs decreased in both percentage and cost PPPM between 1995/96 and 2000/01 from 26% to 10%, 27% to 14% and 8% to 3% respectively. INTERPRETATION: The cost of providing medical care to HIV-positive patients continues to increase, although the burden of costs is distributed differently from before the introduction of HAART, with the costs of drug therapy offsetting the costs of inpatient care and home care. Careful consideration of all aspects of direct costing data is needed when any health economic policy issues are examined.