Chapter 6 Flashcards
A developed country with a mushroom-shaped population pyramid is currently experiencing
an epidemic in the form of a virus. The virus is quick to spread and has a relatively high mortality rate at every age. Early research indicates that the mortality of infected members of the population is 80% higher in children under the age of 10 years.
ii. Give a name for and explain the dynamics of a “mushroom-shaped” population pyramid.
[2]
J2020; Q2 (ii)
A “mushroom-shaped” population pyramid is a Contracting Population Pyramid✓
* and marks the end (or final step) of the demographic transition✓.
It is characterised by low-fertility and low-mortality.✓✓
* This means that there is a shrinking child/young population (due to the low fertility)✓
* and a growing old age population✓ (due to low mortality) and hence increased longevity.✓
* This means that the old age dependency ratio will be increasing✓
* since the dependent population living longer and there is a smaller working population to support it.✓
* This is a sign of a developed country✓ and generally means that the net population growth is negative✓ i.e. the population is contracting✓.
- The population pyramid is called contracting because there are relatively fewer younger adults✓
- Than middle-aged adults✓
- And the population continues to decline from young adulthood into childhood.✓
- Eventually there is some stabilisation at younger ages which look reasonably constant✓
- Implying that the number of new births each year
- Is equal to or less than 50% of the number of child bearing adults✓✓
i.e. 1 child or less per couple.✓
Medical advances have had a profound impact on the burden of disease:
l Improved prevention and health promotion. Medical advances often lead to a better
understanding of the risk factors for diseases and injuries. This knowledge enables more effective prevention strategies, such as lifestyle modifications, vaccination programmes, and public health campaigns. Many prevention strategies are relatively simple and low cost, but genetic screening is an example of a sophisticated screening mechanism.
l Early detection and diagnosis, including advanced imaging techniques and diagnostic tests, enable earlier and more accurate detection of diseases. Early diagnosis can lead to better treatment outcomes and reduced disease severity. For example, screening programmes for conditions like cancer, diabetes, and cardiovascular disease can detect diseases at their earliest, most treatable stages. However, it is important to note that improved diagnostic techniques are also likely to result in more diagnoses.
l Innovative treatments have resulted in more effective treatments of a range of diseases, leading to shorter courses of treatment and hospital stays. Examples of innovative treatments include precision medicine which is tailored to an individual’s genetic makeup and specific disease characteristics, as well as non-invasive surgery.
l Management of chronic conditions has been facilitated by medical and technological advances. These include improved medications and digital health technologies to improve compliance, which allow individuals to take an active role in managing their health and to avoid long-term complications.
l Reduced mortality—or more accurately a decrease in YLL—was the result of interventions as basic as encouraging hand-washing in hospitals and the rollout of childhood vaccination programmes.
l More cutting-edge technologies include the use of mRNA vaccines, advanced trauma care, and surgical techniques.
l Shift to geriatric care because of medical advances, people are living longer. This has shifted the burden of disease towards management of chronic conditions, which are often associated with ageing, and medical care for older persons.
Define the term burden of disease. [ ]
The burden of disease in a public health context means the impact of diseases and injuries on a population, considering various factors relating to the prevalence, severity, and consequences of diseases and injuries.
Define the terms YLL and YLD. [ ]
Years of Life Lost (YLL) measures how a disease burden results in a loss of life years.
Years Lived with Disability (YLD) is the number of years lived with a disability or health condition.
Define DALY. [ ]
The combination of YLL and YLD is the Disability-Adjusted Life Years (DALY), a comprehensive measure of the burden of disease.
State the three main components of demographic change. [ ]
Mortality tends to be the most stable component of the three. l Fertility is variable over time and influenced by social and economic factors. It is measured by the age-specific fertility rate and the total fertility rate (TFR). l Net migration is complex and difficult to model.
Describe the three stages stages of demographic transition.
Demographic transition and ageing populations Stage 1: A decline in mortality—at all ages, but particularly in infants—leads to a drop in the average age and later an increase in the working population.
Stage 2: A decline in fertility means that the population grows but at a decreasing rate and the proportion of elderly people increases.
Stage 3: Mortality and fertility are in balance, resulting in the natural rate of population growth decreasing to zero.
State the 4 main population structures.
Stable
Expansionary—the early stage of demographic transition
Stationary—the end of demographic transition l
Contracting
Define the term “population pyramid”
Histogram showing the size of the population at various ages. [ ]
