Morbidity (VCE SSCE Health and Human Development): Revision Notes

Morbidity

What is morbidity?

Morbidity measures the extent of illness and disease within a population. While mortality statistics tell us about deaths, they only reveal part of the health story. Many Australians experience conditions that significantly affect their health and wellbeing without leading to death. Even conditions that eventually cause death often create substantial illness beforehand. Understanding levels of ill health and disability is therefore essential for assessing overall health status.

Morbidity is defined as ill health in an individual and levels of ill health within a population, typically expressed through incidence and prevalence measures.

Morbidity rate measures how many people suffer from a particular condition during a given time period.

Why morbidity matters

As mortality rates have fallen and Australians live longer, morbidity rates for many conditions have increased. People are now living long enough for various factors to negatively impact their health and wellbeing. Conditions such as obesity have also become more prevalent, leading to increased rates of associated conditions like type 2 diabetes, cardiovascular disease and some cancers. Many non-life-threatening conditions, such as arthritis and osteoporosis, affect large numbers of people and significantly reduce quality of life over extended periods.

Understanding incidence and prevalence

Morbidity can be measured in two important ways: incidence and prevalence. Both provide valuable information about disease burden in the population.

Incidence refers to the number (or rate) of new cases of a disease or condition in a population during a given period, usually a 12-month period. Think of incidence as measuring "new arrivals" of a disease.

Prevalence refers to the total number or proportion of cases of a particular disease or condition present in a population at a given time. Prevalence captures everyone currently living with a condition, not just those newly diagnosed.

The difference between incidence and prevalence

Unlike most infectious diseases, many chronic conditions such as cardiovascular disease and cancer are long-lasting and may never be completely cured. People generally receive a diagnosis for these conditions only once, representing their "incident year". However, because these conditions persist over time, prevalence data becomes particularly important.

Morbidity in Australia

According to the Australian Institute of Health and Welfare, around 75 per cent of Australians experience a long-term health condition. The proportion of people experiencing one or more long-term conditions increases with age.

Common health conditions

Morbidity includes diseases, injuries and disabilities that affect Australians' health and wellbeing.

Most common long-term conditions by gender

The following table shows the most commonly reported long-term conditions in Australia during 2017-18, broken down by gender:

Condition	Males (%)	Males Rank	Females (%)	Females Rank
Long-sighted	27.4	1	32.0	1
Short-sighted	22.5	2	29.7	2
Hay fever and allergic rhinitis	18.9	3	19.7	3
Back problems	16.5	4	16.3	4
Deafness	12.8	5	8.0	12
Anxiety-related disorders	10.6	8	15.7	5
Hypertension	10.5	6	10.7	10
Asthma	10.2	7	12.3	7
Depression and mood disorders	9.5	9	12.0	8
Allergies	9.4	10	15.1	6
Osteoarthritis	6.8	12	11.2	9

Key observations:

• Vision problems (long-sightedness and short-sightedness) are the most common conditions for both genders
• Females have higher rates of most conditions, particularly anxiety-related disorders and allergies
• Males experience higher rates of deafness
• Many of these conditions do not contribute to death but may significantly reduce quality of life over long periods

Morbidity patterns across the lifespan

Morbidity figures represent a snapshot of the entire population. Because Australians are living longer than ever, some conditions are very common in older populations but virtually non-existent in younger groups. Examining the most reported long-term conditions for different age groups helps government and non-government organisations develop appropriate strategies and allocate funding to address the most prevalent conditions in each age bracket.

The table below shows the five most common conditions for each age group in 2017-18:

Age Group	Condition	Per cent
0-14	Mental and behavioural problems	11.1
	Asthma	10.1
	Hay fever	10.0
	Food allergy	5.5
	Short-sightedness	4.5
15-24	Mental and behavioural problems	25.6
	Hay fever and allergic rhinitis	21.4
	Short-sightedness	19.4
	Long-sightedness	12.9
	Asthma	10.2
25-34	Short-sightedness	25.9
	Hay fever and allergic rhinitis	22.8
	Mental and behavioural problems	21.2
	Back problems	14.6
	Asthma	10.7
35-44	Short-sightedness	25.6
	Hay fever and allergic rhinitis	23.8
	Back problems	20.9
	Mental and behavioural problems	20.6
	Long-sightedness	17.3
45-54	Long-sightedness	53.2
	Short-sightedness	34.2
	Mental and behavioural problems	23.8
	Hay fever and allergic rhinitis	22.5
	Back problems	23.2
55-64	Long-sightedness	62.1
	Short-sightedness	41.9
	Arthritis	34.0
	Cardiovascular disease	31.9
	Back problems	28.0
65+	Long-sightedness	61.7
	Arthritis	49.0
	Short-sightedness	40.7
	Endocrine diseases including diabetes	39.1

Healthcare utilisation: morbidity requiring care

Illnesses and disabilities vary in severity, and many people require professional care to improve their health and wellbeing. Morbidity data from doctors and hospitals provides valuable insights into health status and healthcare needs.

GP visits

According to Department of Health data from 2020, around 163 million visits to general practitioners (GPs) were made in 2019-20, which equals approximately 6.5 visits per person each year. Females are more likely to visit doctors than males, though this doesn't necessarily mean they experience more illness—it may reflect greater willingness to seek medical care when symptoms or concerns arise.

GP visits often involve multiple interventions including prescribing medicines, ordering pathology tests (such as urine and blood tests), administering vaccinations, and discussing test results.

Common reasons for GP visits

The table below shows the principal reasons Australians visited their GP in 2015-16:

Principal reason	Percentage of visits
Prescription	8.8
Check-up	8.1
Test results	6.7
Cough	4.1
Immunisation/vaccination	3.3
Administrative procedure	2.5
Back complaint	2.0
Rash	1.8
Throat symptom/complaint	1.8
Blood test	1.5
Fever	1.4
Depression	1.3
Abdominal pain	1.2
Upper respiratory tract infection	1.1
Headache	1.1
Skin symptom/complaint	1.1
Sneezing/nasal congestion	1.0
Hypertension/high blood pressure	1.0
Anxiety	1.0
All other reasons	49.2

Hospital care

Hospital care encompasses treatment for chronic conditions (where patients are admitted to receive ongoing care) and emergency care for unforeseen events requiring medical intervention, such as car accidents, sporting injuries and premature births.

In 2018-19, there were 11.5 million hospitalisations in Australia, with approximately 60 per cent occurring in public hospitals and 40 per cent in private hospitals.

Hospital separation refers to episodes of hospital care that start with admission and end at transfer, discharge or death. This measure helps track the volume and types of hospital care provided.

The major causes of hospital separations in 2017-18 were:

1. Dialysis for kidney disease (1,500,000 separations) - An artificial method of removing waste substances from the blood and regulating levels of circulating chemicals, functions usually performed by the kidneys
2. Cancer (1,500,000 separations) - Including skin, lung, breast and prostate cancers
3. Diseases of the digestive system (1,100,000 separations) - Including intestinal diseases, hernia and dental issues
4. Diseases of the musculoskeletal system (795,000 separations) - Including arthritis, back pain and shoulder pain
5. Injuries and poisoning (782,000 separations) - Including fractures, dislocations and open wounds
6. Diseases of the circulatory system (584,000 separations) - Including heart attack and stroke
7. Diseases of the respiratory system (508,000 separations) - Including pneumonia, chronic obstructive pulmonary disease and asthma
8. Pregnancy and childbirth (290,000 separations) - Including childbirth and IVF treatment

Trends in morbidity

Several important morbidity trends are emerging in Australia. While the long-term effects of some trends on future mortality and morbidity rates take time to become apparent, current patterns are worth noting. Key trends identified by the Australian Institute of Health and Welfare include:

• Significant increase in overweight and obesity prevalence over the past 20-30 years
• Increased rates of impaired glucose regulation (a precursor to type 2 diabetes) since 1980
• Tripled rates of diabetes in the past two decades
• Increased rates of kidney disease, attributed to the increased rates of diabetes

Overweight and obesity trends

The graph above shows clear trends in overweight and obesity prevalence from 1995 to 2017-18:

• All age groups have experienced increases in overweight and obesity rates
• The increases have occurred consistently across the entire time period
• Older age groups (45-54, 55-64, 65-74, and 75+) show the highest rates, with approximately 70-75% affected by 2017-18
• Even the youngest adult age group (18-24) has seen rates climb from around 20% in 1995 to nearly 50% by 2017-18
• Middle-aged groups (45-64) show particularly high rates, approaching 75% in recent years