The Importance of Measuring Health Status
In order to address global health issues, we must understand:
• The factors that influence health status most• The indicators used to measure health status • The key trends that have occurred historically
Determinants of Health
• The interconnected factors that determine an individual’s health status
• Determinants include personal features, social status, culture, environment, educational attainment, health behaviors, childhood development, access to care, and government policy
• Increasing attention is being paid to the “social determinants of health”
Key Health Indicators
Health status indicators are useful for: • Finding which diseases people suffer from• Determining the extent to which the disease
causes death or disability• Practicing disease surveillance
To perform these functions, it is important to use a consistent set of indicators
Table 2.1: Key Health Status Indicators
Source: Data from the Public Health Agency of Canada. What Determines Health. Available at: http://www.phac-aspc.gc.ca/ph-sp/determinants/ index-eng.php#determinants. Accessed November 19, 2010.
Key Health Indicators
Terms• Morbidity- sickness or any departure, subjective or objective,
from a psychological or physiological state of well-being • Mortality- death• Disability- temporary or long-term reduction in a person’s
capacity to function• Prevalence- number of people suffering from a certain health
condition over a specified time period• Incidence- the rate at which new cases of a disease occur in a
population
Key Health Indicators
Classifications of Disease • Communicable disease- illnesses caused by a
particular infectious agent that spread directly or indirectly from people to people, animals to people, or people to animals
• Noncommunicable disease- illnesses not spread by an infectious agent
• Injury- include road traffic injuries, falls, self-inflicted injuries, and violence, among other things
Vital Registration
• Vital registration systems record births, deaths, and causes of death
• An accurate system is key to having quality data on a population
• Many low- and middle-income countries lack a vital registration system
• Developing a system is progress towards understanding and addressing health problems
Measuring the Burden of Disease
• Twp indicators used to compare how far countries are from a state of good health
• Health-Adjusted Life Expectancy (HALE)- summarizes expected number of years to be lived in what might be termed the equivalent of good health
• Disability-Adjusted Life Year (DALY)- a unit for measuring the amount of health lost because of a particular disease or injury
Measuring the Burden of Disease
DALY• “Health gap measure,” indicating losses due to
illness, disability and premature death in a population
• Gives a better estimate of the health of a population than death rate
• Accounts for health conditions like mental illness that rarely cause death
The Global Burden of Disease
Important to understand: • Leading causes of illness, disability, and death
in the world • Variations by age, sex, ethnicity, and
socioeconomic status • Changes over time
Table 2.3: The 10 Leading Causes of Death and DALYs
Source: Adapted with permission from Lopez AD, Mathers CD, Murray CJL. The burden of disease and mortality by condition: data, methods, and results for 2001. In: Lopez AD, Mathers CD, Ezzati M, Jamison DT, Murray CJL, eds. Global Burden of Disease and Risk Factors. Washington, DC and New York: The World Bank and Oxford University Press; 2006.
The Global Burden of Disease
Causes of Death by Region • Higher income countries tend to have a greater
burden of noncommunicable disease • Lower income countries to have a greater
burden of communicable disease • Africa and South Asia are set apart by their
large burdens of communicable disease
Table 2.4: The Leading Causes of the Burden of Disease
Source: Reprinted with permission from Lopez AD, Mathers CD, Murray CJL. The burden of disease and mortality by condition: data, methods, and results for 2001. In: Lopez AD, Mathers CD, Ezzati M, Jamison DT, Murray CJL, eds. Global Burden of Disease and Risk Factors. Washington, DC and New York: The World Bank and Oxford University Press; 2006:91.
The Global Burden of Disease
Causes of Death by Age• Children in low- and middle-income countries
often die of communicable disease • HIV/AIDS and TB are among the leading
causes of death among adults in low- and middle-income countries
The Global Burden of Disease
The Burden of Deaths and Disease Within Countries
In most low- and middle-income countries: • Rural people will be less healthy • Disadvantaged ethnic minorities will be less
healthy• Women will suffer from their weak social positions• Poor people will be less healthy• Uneducated people will be less healthy
Risk Factors
• Risk factor- an aspect or personal behavior or life-style, an environmental exposure, or an inborn or inherited characteristic, that, on the basis of epidemiological evidence, is known to be associated with health-related conditions considered important to prevent
• Most important risk factors in low- and middle-income countries are malnutrition, high blood pressure and high cholesterol, smoking, and unsafe sex
Table 2.8:The Leading Risk Factors for the Burden of Disease, 2001, Low- and
Middle-Income and High-Income Countries, Ranked in Order of Percent of Total DALY
Demography and Health
Population Growth • Majority of population growth will occur in
low- and middle-income countries • Put pressure on the environment • Create need for more infrastructure and
services
Demography and Health
Population Aging• Population of the world is aging • Implications for burden of disease because
people will be living longer with morbidities and disabilities
• Healthcare financing will be affected by change in ratio of working people to those over 65 years
Demography and Health
Urbanization• Majority of the world’s population lives in
urban areas for the first time • Enormous pressure on urban infrastructure like
water and sanitation
Demography and Health
The Demographic Divide • Highest income countries: low fertility,
declining populations, aging populations• Lowest income countries: relatively high
fertility, growing populations
Demography and Health
The Demographic Transition• Shift from pattern of high fertility and high mortality
to low fertility and low mortality• Mortality declines due to better hygiene and nutrition• Population grows with younger share of population
increasing• Fertility declines • Population growth slows and older share of
population increases
Demography and Health
The Epidemiologic Transition• Shift from burden of disease dominated by
communicable disease to burden of disease dominated by noncommunicable disease
• Most low-income countries are in ongoing transition so they face large burdens of communicable and noncommunicable disease
Progress in Health Status
• Improvements in raising life expectancy and improving health not uniform across countries
• Life expectancy in South Asia and sub-Saharan Africa lag that in other regions
• Life expectancy in Europe and Central Asia changed little due to break-up of Soviet Union
• Life expectancy in East Asia has increased dramatically due to rapid economic growth
Looking Forward
Economic Development• Economies of low-income countries need to
grow in order to invest in health • Impact of economic development will depend
on countries investing in areas that improve health such as water, sanitation, and education
Looking Forward
Scientific and Technological Change • Development of vaccines, drugs, and
diagnostics • Country’s ability to adopt these changes will
determine their effect on health
Looking Forward
Climate Change • Impact not entirely clear • Possible migration from places that become
inhabitable • Adverse weather • Possible change in populations of disease
vectors
Looking Forward
Political Stability • Necessary for long-term gains in health • Instability causes illness, disability and death
as well as breakdown of infrastructure and services
Looking Forward
Emerging and Re-emerging Infectious Disease
• Occurrence and impact difficult to predict • Pandemic flu• Anti-microbial resistance
Looking Forward
Projecting the Burden of Disease • Substantial changes from 2004 to 2030• Low- and lower-middle-income countries will
shift away from communicable disease • Causes associated with aging will increase in
importance • Mental health issues will increase in importance
The Development Challenge of Improving Health
• Health usually increases as national income increases
• Some countries have achieved higher life expectancies than their incomes would predict
• This is possible with investments in nutrition, education, good hygiene, and low-cost services that have a high impact such as vaccination programs