Sprawl and Health

Colman 2001 - "Cost of Obesity in British Columbia"

Colman, Ronald; Dodds, Colin; Wilson, Jeff
"Cost of Obesity in British Columbia"
January, 2001. GPI Atlantic
On the Web
Relevance: high

Direct costs for obesity-related diseases cost the British Columbia health care system at least CAN$217.3 million a year (2.6% of the health care budget) in 1997. This is a very conservative estimate, so a reasonably higher estimate is $380 million, or 4.5% of the provincial health budget. Note that obesity is defined as BMI>27 for the conservative estimate and BMI>25 for the high estimate.

Using the assumption that the direct health care costs are only 45.7% of the total economic burden of illness, obesity could cost a total of $475.5 million to $831.5 million each year. At the time of writing, $830 million was 0.9% of BC's GDP.

Method: The author uses Birmingham's method of population attributable fractions applied to the BC population and 1997 medical costs.

Brauer 2000 - "Evaluation of Ambient Air Pollution in the Lower Mainland of British Columbia"

Brauer, Michael; Brumm, Jochen; Ebelt, Stefanie
"Evaluation of Ambient Air Pollution in the Lower Mainland of British Columbia: Public Health Impacts, Spatial Variability, and Temporal Patterns"
Submitted to the Administrative Council of Lower Mainland Medical Health Officers
On the Web
Relevance: high

This study estimates that 0 to 600 excess deaths annually in the BC Lower Mainland each year can be attributed to anthropogenic outdoor air pollution. However, most of these deaths are for individuals age 65 and older and associated with cardiovascular disease.

This study modeled where certain air pollutants are concentrated, finding that Vancouver's air is not always dirtiest: "CO and NO2 concentrations were higher in Vancouver relative to locations in the eastern part of the region. In contrast, O3 concentrations were significantly higher in the Fraser Valley relative to Vancouver/Burnaby. PM10 did not exhibit much spatial variability, with concentrations being relatively homogeneously distributed within the region." See maps in the study.

The study also compared Vancouver's average concentrations to other cities including Seattle and Portland. For annual averages, Vancouver ranks best on PM10, CO, and ozone, while Seattle and Portland rank better on NO2.

BC Lung Assoc 2005 - "Health and Air Quality 2005 - Phase 2: Valuation of Health Impacts from Air Quality in the Lower Fraser Valley Airshed"

RWDI AIR Inc (for British Columbia Lung Association)
"Health and Air Quality 2005 - Phase 2: Valuation of Health Impacts from Air Quality in the Lower Fraser Valley Airshed"
July 15, 2005
On the Web
Relevance: high

This study estimates that a 10% reduction in fine particulate matter and ozone pollution in the Lower Fraser Valley (LFV) could produce $195+/- $122 million annually in 2010 (2003$ discounted) in health benefits. (I think these are not only direct health costs, but also use some other valuation method.)

• The study uses a linear model and assumes no thresholds, so the estimates are scalable to 1%, 20%, etc. The authors say that a 1% improvement would save $29 million (undiscounted) in 2010.
• They also note that the benefits from a given improvement in PM2.5 are about 10 times greater than the benefits from a similar improvement in ozone.

British Columbia 2003 - Air Quality in British Columbia, a Public Health Perspective

British Columbia Provincial Health Officer, Ministry of Health Services.
Every Breath You Take…Provincial Health Officer’s Annual Report 2003.
Air Quality in British Columbia, a Public Health Perspective.
2004 Victoria, BC
On the Web
Relevance: high

This report covers the sources, distribution, and health effects and costs of air pollution.

Sources and distribution: Air pollution is neither evenly distributed around BC nor concentrated in Vancouver. For example, Vancouver has relatively low levels of particulate matter (excluding road dust) and ozone but relatively high levels of NO2, SO2, and CO. In the Lower Fraser Valley air shed (including Whatcom County, WA):

• mobile sources (excluding marine vehicles) account for 41% of smog-forming pollutants. according to an inventory in 2000. 
• 83% of CO comes from light-duty and off-road vehicles
• light-duty vehicles are responsible for 23% of NOx, 23% of VOCs, 3% of PM2.5

Health effects. The report estimates that 712 hospital admissions and 944 emergency room visits are due to outdoor air pollution. It also very informally estimates that the health burden from outdoor air pollution costs CAN$85 million annually. Estimates of annual deaths from outdoor air pollution range widely.

• Low estimate: 82
• Low intermediate estimate: 25-250
• High intermediate estimate: 115-402
• High estimate: 644
• Estimate of delayed mortality for PM2.5: 71-110

Ebelt 2005 - "Exposure to Ambient and Nonambient Components of Particulate Matter"

Ebelt, Stefanie T; Wilson, William E; Brauer, Michael.
"Exposure to Ambient and Nonambient Components of Particulate Matter: A Comparison of Health Effects"
Epidemiology
May 2005; v.16, n.3; pp.396-405
On the Web
Relevance: medium

Intro: Using a small sample of pulmonary patients in Vancouver, the authors measured exposure to particulate matter and health effects, trying to separate out influence of ambient and nonambient particles on lung function, heart rate, and blood pressure.

Findings: They found that ambient exposure was not correlated with nonambient or personal exposure. They also found that ambient exposure was a better predictor of health effects. In contrast nonambient and personal exposures were not associated with health effects, except in the wrong direction for lung function. The authors caution that this is a small study and the results are not conclusive.

Canada 2004 - "Estimated Number of Excess Deaths in Canada Due to Air Pollution"

Judek, Stan; Jessiman, Barry; et al.
"Estimated Number of Excess Deaths in Canada Due to Air Pollution"
Health Canada & Environment Canada
August 30, 2004
On the Web
Relevance: medium

This study estimates the number of annual excess deaths due to current air pollutions levels in 8 major cities. They estimate that, in the Greater Vancouver Regional District, 230 deaths are due to short-term air pollution and 440 deaths are due to long-term air pollution, for a total of 680 (sic). They also estimate that this is 5% (range 3%-7%) of deaths from all causes.

For the eight cities across Canada, the study estimates that 1,800 (+/-700) deaths are due to short-term air pollution; 4,200 (+/-2,000), due to long-term; for a total of 5,900 (+/-2,100), or 8% (range 5%-11%) of all preventable deaths in those cities in Canada.

Note that short-term and long-term deaths may not be additive, but may rather overlap, making the total less than the sum of its parts.

Hirdes 1992 - "The importance of social relationships, socioeconomic status and health practices with respect to mortality among healthy Ontario males"

Hirdes, Forbes
"The importance of social relationships, socioeconomic status and health practices with respect to mortality among healthy Ontario males"
Journal of Clinical Epidemiology
February 1992; v45, n2; pp 175-182
On the Web
Relevance: Medium

The authors examined 2000 men in Ontario and found that social relationships had "a strong association with mortality." Unfortunately, their social relationships index was comprised of marital status, number of children, family contact, and participation in voluntary associations -- only the last of these is conceivably affected by sprawl. Also, the strong association of social capital to mortality is in the comparison between the highest scoring 10% in social capital and the lowest scoring 10%. It's not clear whether sprawl is affect social capital in these extremes or in the middle 80% (where, in turn, the effects on mortality are less pronounced).

Interestingly, the effect of income was greater than the effect of social capital (adjusted relative risk of 0.41 versus 0.30). The effect of income is even greater because the risk factors for income include the top 20% versus the bottom 20% (not just top and bottom deciles, as for social capital).

Veenstra 2002 - "Social capital and health (plus wealth, income inequality, and regional health governance)"

Veenstra
"Social capital and health (plus wealth, income inequality and regional health governance)"
Social Science and Medicine
March 2002; v54, n6; pp 849-868
On the Web
Relevance: Medium-high

Describes a study of 30 health districts in Saskatchewan, comparing population health with social capital, income inequality, wealth, and governance. Social capital meant associational and civic participation. Two findings stand out:

• The author found no evidence of a relationship between social capital and good governance in the health districts.
• Low social capital was correlated to high mortality; high income inequality was also correlated to high mortality. The author writes, "the two may be co-mingled somehow when it comes to population health, although they were not significantly related to one another."

Veenstra's findings are promising because his use of social capital--associational and civic participation--is the same kind that may be affected by sprawl. And while the effects of social capital on mortality are "co-mingled" with income inequality, there is a relationship.

B.C Health Planning 2004 - "The Cost of Physical Inactivity in British Columbia"

Colman, Ronald; Walker, Sally
"The Cost of Physical Inactivity in British Columbia"
B.C. Ministry of Health Planning
November 2004
On the Web (pdf)
Relevance: high

The authors use data from the Canadian Community Health Survey, the Economic Burden of Illness in Canada, and the literature to calculate the cost of physical inactivity in BC.  They estimate that physical inactivity costs the British Columbian health care system $211 million (2001CAN$) (1.8% of provincial health spendig) a year in direct costs.  They also estimate that indirect costs of productivity losses add up to $362 million a year due to premature death and disability, leading to a total cost of $573 million.  5% (1400) of all premature deaths are due to physical inactivity. This results in more than 4,380 potential years of life lost annually.

Birmingham 1999 - "The Cost of Obesity in Canada"

Birmingham, C. Laird; Muller, Jennifer L; et al
"The Cost of Obesity in Canada"
Canadian Medical Association Journal
February 23, 1999; v.160, n.4; pp.483-488
On the Web
Relevance: high

The authors reviewed the literature to calculate the direct medical cost of obesity in Canada.  They estimate that obesity cost over $1.8 billion, or 2.4% of the total health care expenditures, in Canada in 1997. The three top contributors were hypertension ($656.6 million), type 2 diabetes ($423.2 million), and coronary artery disease ($346.0 million).