Module 3 Flashcards
Global Burden of Disease
global burden of disease
The GBD Study tabulates all available information about the causes of deaths and disability in the world and DALYs are used to report on the health status of countries
The GBD Study is an ongoing endeavour that quantifies the burden of premature mortality and disability for major diseases or disease groups by country. Data can be broken down by age, sex, and race.
GBD Group 1
○ Communicable diseases, maternal, neonatal, perinatal, and nutritional conditions
○ These represent 2 out of every 10 deaths that occur globally
○ These conditions occur largely in low income populations due to inadequate access to healthcare, particularly preventative care
○ Although the global rate of death is estimated at 20%, the rate is 50% in low socio-demographic index (SDI) regions, and only 5% in high SDI regions
GBD Group 2
○ Non-communicable diseases (CAD, cancer, mental illness)
○ Accounts for about 7 out of 10 deaths globally.
○ Out of the three health categories, the majority of deaths are due to non-communicable diseases
○ Despite accounting for roughly 74% of deaths globally, many of the lower SDI countries do not have a rate this high
○ In 2019, NCDs were responsible for 41% of deaths in low SDI regions, and 88% in high SDI regions
GBD Group 3
○ Injuries (car crashes, suicide, war injuries)
○ Represents roughly 1 in 10 deaths that occur globally
○ This category represents the largest difference between the sexes, with injuries accounting for 12% of overall male deaths and 6% of female deaths in 2019
racial and ethnic differences in disease rates
Indigenous populations may be less likely to seek or receive medical treatment when injured as a result of stigma and historical oppression.
DALY
Disability Adjusted Life Years is a measure of overall disease burden, which is expressed as the cumulative number of years lost due to ill-health, disability, or early death.
DALY = YLD + YLL
YLD
To incorporate disability into a single measure of burden, Years Lived with Disability (YLD) is used.
YLD multiplies the number of years a person has a condition that affects their quality of life. Each condition has a weighting factor between 0 and 1, with 0 being perfect health and 1 being death. The rating is indicative of the degree to which a disease negatively impacts an individual’s life.
YLL
Years of Life Lost
This measure of premature mortality has two defining characteristics.
YLL = (Number of Deaths) x (Life Expectancy - Age of Death)
Ultimately, the YLL equation places more weight on illnesses that result in early mortality, because dying young has a bigger impact on both the individual and society at large.
communicable diseases
These diseases spread from one person to another, from an animal, or even the environment, to a person. Typically, this occurs through airborne droplets or bodily fluids containing a virus, bacterium, or parasite. Nutritional, maternal, and neonatal conditions are often group with communicable diseases in the study of GDB. (group 1)
burden of communicable diseases
Communicable diseases such as HIV, TB, and malaria present a significant burden for low income countries, but less than 10% for high income countries.
HIV
HIV is a disease that attacks the body’s white blood cells and weakens the body’s immune system. By the end of 2019, there were 38 million people in the world living with HIV, and only 67% of them having access to antiretroviral therapy.
To date, HIV has taken 33 million lives, making it one of the major global public health issues.
HIV mechanism of action and transmission
Mechanism of Action:
○ HIV infects Helper T cells, destroying them over time and eventually causing Acquired Immunodeficiency Syndrome (AIDS)
Transmission:
○ HIV is spread from person to person via bodily fluids (semen, vaginal fluid, blood, breast milk)
HIV prevention and treatment
HIV is typically treated using antiretroviral therapy (ART), which can greatly prolong life and suppress symptoms, but does not cure the disease
Prevention strategies include:
§ Single condom use
§ Elimination of mother-to-child spread with ART during pregnancy and breastfeeding
§ Testing and counselling services
§ Harm reduction for people who use drugs, including needle and syringe problems
HIV/AIDS in Indigenous Canadians
Social and economic factors have placed the Indigenous peoples in Canada at a higher risk of HIV/AIDS compared to non-Indigenous Canadians. In 2017, Indigenous Peoples accounted for only 4.9% of Canada’s total population, yet made up 20.1% of total HIV cases.
Socioeconomic factors that may contribute to the increase in the risk of HIV/AIDS in Indigenous Peoples include domestic violence, stigma, discrimination, and injection drug use.
Additionally, the mistrust and lack of health services further perpetuates poor HIV and health outcomes within this population.
HIV/AIDS risk factors in Indigenous Canadians
Among the total Indigenous population, Indigenous youth are at a greater risk of contracting HIV AIDs. Unfortunately, a lack of health education services and denial of this crisis has resulted in a low-perceived risk of the virus in youth.
Furthermore, substance use, partially injection drug use, is strongly associated with HIV infection among Indigenous youth in Canada. Indigenous youth report a higher likelihood of sharing equipment and less access to risk reduction programs such as methadone clinics or needle-exchange programs, putting their population at 22 times more risk of HIV than the general population
barriers to substance use harm reduction programs
- lack of on-site methadone treatments
- lack of trust in treatment programs
- discriminatory behaviour experienced in treatment programs
Canadian Aboriginal Aids network
there are programs and services being created with a holistic approach to HIV and AIDS, other communicable diseases, and co-morbidity issues. One such service is the Canadian Aboriginal Aids Network (CAAN),
ensures access to HIV and AIDS related services
The CAAN promotes a social determinants of health framework through advocacy, and provides accurate and up to date resources on these issues in a culturally relevant manner for Aboriginal Peoples wherever they reside
TB
TB is caused by Mycobacterium tuberculosis; a bacterium that has infected one quarter of the world’s population. However, only 5-15% of those infected will develop an active TB infection. The risk is higher in people with a compromised immune system, such as those who are malnourished or co-infected with HIV. In 2019, TB infected 10 million people and was responsible for 1.4 million deaths.
TB mechanism of action
○ TB usually attacks the lungs (pulmonary), but can also affect other parts of the body (extrapulmonary), including lymph nodes, kidneys, urinary tract, and bones
○ When an individual has M. tuberculosis bacteria in their body but does not feel sick or show symptoms, they have latent TB (LTB)
○ If LTB goes untreated, approximately 5-10% of infected individuals will develop active TB
○ Individuals with active TB show signs and symptoms, and are considered infectious.
TB transmission
○ TB is primarily an airborne disease that is spread through the air from person to person
○ When a person with infectious TB coughs or sneezes, droplet nuclei containing the bacteria are released into the air
○ If another person inhales the air, they may become infected
TB treatment and prevention
○ LTB can be treated and cured with antibiotics as a means to prevent active TB from developing. When individuals have active TB, they have to take multiple antibiotics for 6-9 months to kill all the bacteria (compared to 3-4 months for LTB)
○ Like with any other antibiotic treatment, there is variable adherence, with many individuals stopping the antibiotics early. Such behaviour has caused drug resistance to become a major global health concern.
○ If someone is exposed to or infected by an individual with multi-drug resistant TB, preventative treatment may not be an option
TB in Indigenous communities
Unlike the success of Indigenous communities in facing COVID 19, Indigenous communities have struggled with high and persistent TB infections rates. In most of Canada, the risk of developing TB is low, however amongst Indigenous communities, the risks are much higher
Indigenous individuals are at a greater risk for contracting and developing active TB often due to lack of health promoting conditions. These conditions including living in overcrowded and poorly ventilated homes, lack of food security, and comorbidities such as diabetes, HIV, etc
steps for reducing TB in Indigenous communities
- Enhance TB care and preventative programming
- Reduce poverty, improve social determinants of health, and create social equity
- Empower and mobilize communities
- Strengthen TB care and prevention capacity
- Develop and implement Inuit specific solutions
- Ensure accountability for TB elimination
malaria
Malaria is caused by the parasite Plasmodium, which can be transmitted between humans by mosquitoes. Malaria is more prevalent but less deadly than HIV, with 229 million cases and 409 000 deaths in 2019. the WHO Africa region carries the greatest burden from malaria, having 94% of all global cases in 2019
malaria MOA
○ After a dormant period in the liver, the parasite enters the bloodstream and infects the RBCs, often causing them to burst. There is also evidence that the parasite impairs the ability of key cells of the immune system to trigger an efficient immune response, which might explain why patients with malaria are susceptible to a wide range of other infections and fail to respond to several vaccines.
○ Symptoms may include headache, abdominal pain, chills, shaking, fever, and sweats
○ Malaria can cause seizures, anemia, jaundice, heart failure, kidney failure, coma, and even death
malaria transmission
○ Plasmodium is transmitted through mosquito bites that allow the parasite to enter the bloodstream.
○ You cannot get malaria just by being near a person who has the disease
malaria treatment and prevention
○ Fortunately, malaria is curable using anti-malarial drugs, and preventable using insecticide treated mosquito nets and indoor sprays
other group 1 conditions
Although maternal, neonatal, and nutritional conditions are not technically communicable diseases, they are grouped with communicable diseases by the GBD tool
One of the many reasons why these are grouped together is because there is a significant interplay between these conditions and communicable diseases. The conditions can either exacerbate the symptoms of communicable diseases or completely mask them, increasing the Public Health concern. The condition itself can be a result of a communicable disease
Additionally, this grouping makes sense because maternal, neonatal, and nutritional disorders are seen more frequently in low SDI countries, much like communicable diseases.
