L5 Global burden of chronic diseases

Define global burden of chronic disease

The current burden of chronic diseases reflects past exposure to the risk factors. Future burden will be affected by current exposures.

• causative factors = Truth

• Associated factors = risk

When was the Global Burden Disease (GBD) study started ? How was it studied ?

• Start in 1990

• Health effects of more than 100 diseases and injuries for 8 regions of the world was studied

• A new metric – Disability - adjusted life year (DALY) was introduced

What are the categories of the burden (cause) of disease that lead to death and DALY ?

Group I

• communicable, maternal and perinatal condition (meaning in the 1 st week after birth) and nutritional disorder

Group II

• non - communicable diseases

Group III

• injuries, including road traffic accidents (RTA), falls, self - inflicted injuries and violence

State the formula of DALY

Disability-adjusted life year = Years of life lost (YLLs) 早死幾多年 + Years lived with disability (YLDs)

• DALYs = YLLs + YLDs

  • DALYs = (N x L) + (I x L x DW)

• Years of life lost (YLLs) = premature mortality

• Years lived with disability (YLDs) = Morbidity 發病率, years lived in less than ideal health

What is the meaning of the calculated DALY means ?

One DALY equals one lost year of healthy life . DALYs allow us to estimate the total number of years lost due to specific causes and risk factors at the country, regional, and global levels. It can be thought of as a measurement of the “gap” between current health status and an ideal health situation where the entire population lives to an advanced age, free of disease and disability.

state the 2 principle of DALY

Principle #1: The only differences in the rating of a death or disability should be due to age and sex, not to income, culture, location, social class.

Principle #2: Everyone in the world has right to best life expectancy in world

What is disability weight ?

(will be given in exam)

• weight factor that reflects the severity of the disease on a scale from 0 (perfect health) to 1 (equivalent to death).

• Used in YLD calculation

Why it might be difficult to give a standardize disability weight ?

because experience of disability varies so much based on:

Individual
Living conditions
Level of community support, Access to health care

State the formula of YLD (year lived with disability)

YLD = I x L x DW

• I = number of incident cases

• L = average duration of the disease until remission (years)

  • ?/52 = weeks

  • ?/365 = days

  • ?/12 = months

• DW = disability weight

State the formula of YLL (Years of life lost)

YLL = N x L

• N = number of deaths ppl

• L = standard life expectancy at age of which death occurs in years (早死咗幾多年)

Calculate the DALY for the follow situation:

100,000 adults are stricken by lightening for 2 years with a disability weighting of 0.6 ; 20% die at 80 years old.

Assume at 80 years old death prematurely, you have 8 more years to live

DALYs = (N x L) + (I x L x DW)

(100000 × 0.2 × 8) + (100000 × 2 × 0.6) = 280000

[If ask in MC, choose the closest ans, won’t have the exact ans.]

What is the benefits and purpose of using DALY ?

DALYs allow us to estimate the total number of years lost due to specific causes and risk factors at the country, regional, and global levels.

• It takes account into both the years of life lost and the possibility of having burden of living with disease / disability without resulting in dying earlier than expected

  • It allows for comprehensive, consistent and comparable information on diseases and injuries as a health indicator allowing surveillance and evaluate overall health

• Allow direct comparison of burden across diseases

• Summing burden across diseases

• Permit comparing treated and untreated conditions

• Compare different disease interventions: Treatment expansion vs Prevention campaigns

• With the objective data of the affected population, health policy & funding can be properly used in dealing with the situation.

Which disease ranked the first in both cause of death and DALY in Sub-Saharan Africa in 2013 ?

HIV/ AIDS

List the Chronic Diseases, which is the largest cause of death

1. Cardiovascular disease (17 million deaths)

2. Cancer (7 million)

3. Chronic lung diseases ( 1 million)

4. Diabetes Mellitus ( 1 million)

What is the leading modifiable risks factors for non-communicable disease ?

• Tobacco use

• Unhealthy diets

• Lack physical activity

• alcohol use

Define what is global shift in disease burden

Definition: The ongoing transition in the primary causes of illness and death worldwide, characterized by:

1. Decline in infectious diseases (e.g., malaria, HIV, tuberculosis) and maternal/childhood conditions.

2. Rise in non-communicable diseases (NCDs) (e.g., heart disease, cancer, diabetes) and injuries.

This shift is driven by socioeconomic development, aging populations, and globalization.

Define what is epidemiological transition

Definition: A theory describing the long-term shift in disease patterns and causes of death within populations, driven by socioeconomic development, demographic changes, and public health advancements. It explains how societies transition from high mortality from infectious diseases to dominance of non-communicable diseases (NCDs).