Causes of Death

Definitions

Near natal: Near the time of birth.

Mortality: Death.

Morbidity: The condition of suffering from a disease.

Comorbitities: The presence of two or more long-term health conditions.

Life Expectancy: The average period a person can be expected to live.

Healthy life expectancy: The average period a person can expect to live in good health. This is always less than life expectancy and is location dependent.

Causes of Death

In general, the global mortality rates are decreasing. However, the primary causes of death changes depending on the age range. Scientists can target these in order to increase life expectancy and prevent premature deaths.

Under 5 Year Olds

The leading cause of child mortality is infections.

  • In low income countries: 25 near natal deaths per 1000.

  • In high income countries: 2 near natal deaths per 1000.

Therefore, infant mortality isn't a lack of knowledge but rather a lack of funding.

However, global child mortality rates are decreasing due to:

  • Increased global vaccinations (e.g MMR and the Rotavirus vaccine).

  • Better sanitation (yet this can still be greatly improved, 2 billion people don’t have access to clean drinking water).

  • Decreased malnutrition (nevertheless, this still affects 700 million people globally).

  • Decrease in malaria (77% of deaths caused by malaria are under 5 year olds).

5-50 Year Olds

The two leading causes of death in this age category is:

  • Traffic accidents and accidents at work.

  • Suicide and murder.

Death rates in this category have decreased due to:

  • Better scientific knowledge, diagnostic equipment and interventions.

  • Increased car safety (deaths caused by traffic collisions are greatest in middle income countries as car safety standards don’t apply but many people own cars).

  • Public health campaigns are decreasing smoking and encouraging healthy living.

  • Better mental health support and campaigns (e.g the “Heads Together” campaign).

50-75 Year Olds

At this age, non-communicable diseases are the leading cause of death (cardiovascular diseases, strokes and cancer). These diseases are decreasing for a multitude of reasons:

  • Heart diseases and stroke: reduction in air pollution, statins/beta blockers, clot-busting drugs, public health campaigns.

  • Cancer: better treatment (chemotherapy and radiotherapy), more screening programs, faster diagnosis, decrease in number of people smoking.

However there are pushbacks slowing the rate of the decline in death rate:

  • Antimicrobial resistance: MRSA and Colistin-resistant bacteria/superbugs have lead to an increase in death relating to antibiotic resistant bacteria.

  • Increasing obesity rates: In the UK, 26% of adults are obese which greatly increases the risk of a heart related diseases (12% increase in the likelihood of coronary heat disease) and strokes (24% increase).

  • Climate change:

    • This directly causes deaths due to increased extreme weather events and heat stroke.

    • This also indirectly causes death as heat stress can affect farm produce in lower income countries leading to famine. It also enables vector borne diseases (e.g malaria carried by mosquitos) to spread further as climates which would not usually support these mosquitos, can now due to the temperature increase.

75+ Year Olds

The leading causes of death in this category are degenerative diseases (dementia, Parkinson’s etc.) and other non-communicable diseases (heart diseases and cancer).

  • Dementia is the leading cause of death in women (14% of female deaths in 2021).

  • Ischemic heart disease is the leading cause of death in men (12.4% of male deaths in 2021).

As people are living longer they accumulate comorbidities which makes it more difficult to diagnose and treat. (75% of 75 year olds have more than one long term condition).