Geographical variation in disease: diabetes, cardiovascular and chronic kidney disease

Aboriginal or Torres Strait Islander: a person of Aboriginal or Torres Strait Islander descent who identifies as an Aboriginal or Torres Strait Islander.

additional diagnosis: a condition or complaint that either coexists with the principal diagnosis or arises during the hospitalisation. An additional diagnosis is reported if the condition affects patient management.

age structure: The relative number of people in each age group in a population.

age-specific rate: A rate for a specific age group. The numerator and denominator relate to the same age group.

age standardisation: A way to remove the influence of age when comparing populations with different age structures. This is usually necessary because the rates of many diseases vary strongly and usually increase with age. The age structures of the different populations are converted to the same ‘standard’ structure, and then the disease rates that would have occurred with that structure are calculated and compared. Age-standardised rates are usually expressed per 100,000 population.

associated cause(s) of death: all causes listed on the death certificate other than the underlying cause of death. They include the immediate cause, any intervening causes and conditions that contributed to the death but were not related to the disease or condition causing the death. See also cause of death.

biomedical data: biomedical or measured data―in the form of markers found during blood and urine testing―is the most accurate way to measure the prevalence of chronic diseases such as diabetes and chronic kidney disease. In the 2011–12 Australian Bureau of Statistics Australian Health Survey:

• 2 tests were undertaken to detect biomedical signs of diabetes: a measure of fasting plasma glucose (FPG) and a measure of glycated haemoglobin (HbA1c).
• 2 tests were undertaken to identify signs of chronic kidney disease by determining kidney function – estimated glomerular filtration rate (eGFR) and kidney damage (albumin creatinine ratio – ACR).

blood pressure: The force exerted by the blood on the walls of the arteries as it is pumped around the body by the heart. It is written, for example, as 134/70 mmHg, where the upper number is the systolic pressure (the maximum force against the arteries as the heart muscle contracts to pump the blood out) and the lower number is the diastolic pressure (the minimum force against the arteries as the heart relaxes and fills again with blood). Levels of blood pressure can vary greatly from person to person and from moment to moment in the same person. See also high blood pressure/hypertension.

body mass index (BMI): The most commonly used method of assessing whether a person is within a healthy weight range, underweight, overweight or obese. It is calculated by dividing the person's weight (in kilograms) by their height (in metres) squared; that is: BMI = weight (kg) / height (m)². For both men and women, underweight is a BMI below 18.5, a healthy weight range is from 18.5 to less than 25, overweight is from 25 to less than 30, and obese is 30 and over. Sometimes overweight and obese is combined, and is defined as a BMI of 25 and over.

burden of disease: The quantified impact of a disease, injury or risk factor on a population, using the disability-adjusted life year (DALY) measure. One DALY is one year of 'healthy life' lost due to illness and/or death. The more DALY associated with a disease or injury, the greater the burden. The DALY is produced by combining the non-fatal and fatal burden together. People generally experience more burden as they age.

cardiovascular disease/condition: Any disease of the circulatory system, namely the heart (cardio) or blood vessels (vascular). Includes angina, heart attack, stroke and peripheral vascular disease. Also known as circulatory disease.

cause of death: the causes of death entered on the Medical Certificate of Cause of Death are all diseases, morbid conditions or injuries that either resulted in or contributed to death, and the circumstances of the accident or violence that produced any such injuries. Causes of death are commonly reported by the underlying cause of death. See also associated cause(s) of death.

choropleth map: thematic map used to represent statistical data through various shading patterns or symbols on predetermined geographic areas (i.e. countries). For this product the maps represent the geographical variation of disease impact using a sequential colour scheme; darker colours represent high values (high impact) while lighter colours represent low values (low impact).

chronic kidney disease (CKD): Refers to all conditions of the kidney, lasting at least 3 months, where a person has had evidence of kidney damage and/or reduced kidney function, regardless of the specific cause.

confidence interval (CI): a statistical term describing a range (interval) of values within which we can be 'confident' that the true value lies, usually because it has a 95% or higher chance of doing so.

coronary heart disease: is the most common form of CVD. There are 2 major clinical forms – heart attack and angina. Heart attack is a life-threatening event that occurs when a blood vessel supplying the heart itself is suddenly blocked, causing damage to the heart muscle and its functions. Angina is a chronic condition in which short episodes of chest pain can occur periodically when the heart has a temporary deficiency in its blood supply.

current smoker: Reported smoking daily, weekly or less than weekly at the time of the survey.

diabetes (diabetes mellitus): a chronic condition where the body cannot properly use its main energy source – the sugar glucose. This is due to a relative or absolute deficiency in insulin, a hormone produced by the pancreas that helps glucose enter the body’s cells from the bloodstream and be processed by them. Diabetes is marked by an abnormal build-up of glucose in the blood; it can have serious short- and long-term effects. For the three main types of diabetes, see type 2 diabetes.

dialysis: a medical procedure that artificially cleans the blood to remove waste products that build up (a function that kidneys would normally perform). It is most often required due to kidney failure.

education–lowest: Educational attainment is a single measure of a person’s overall level educational attainment whether it be a school or non-school qualification. The proportion of people aged 25–74 who had a secondary or lower education (including no school qualification).

education–highest: Educational attainment is a single measure of a person’s overall level educational attainment whether it be a school or non-school qualification. The proportion of people aged 25–74 who had bachelor degree or higher educational level.

episode of care: The period of admitted patient care between a formal or statistical admission and a formal or statistical separation, characterised by only one care type (see care type and separation).

estimated resident population (ERP): The official ABS estimate of the Australian population. The ERP is derived from the 5-yearly Census counts and is updated quarterly between each Census. It is based on the usual residence of the person. Rates are calculated per 1,000 or 100,000 mid-year (30 June) ERP.

fatal burden: The burden from dying prematurely as measured by years of life lost. Often used synonymously with years of life lost, and also referred to as ‘life lost’.

heart failure: occurs when the heart functions less effectively in its role of pumping blood around the body. Although it can occur suddenly, it usually develops over many years, as the heart gradually becomes weaker and works less effectively.

heart, stroke and vascular diseases: is a subset of CVD including only the most common and serious types of CVD: coronary heart diseases (CHD) (angina, heart attack and other ischaemic heart diseases) – also known as ischaemic heart disease – erebrovascular disease (including stroke), oedema, heart failure and diseases of the arteries, arterioles and capillaries.

high blood pressure/hypertension: The definition of high blood pressure (also known as hypertension) can vary but a well-accepted one is from the World Health Organization: a systolic blood pressure of 140 mmHg or more or a diastolic blood pressure of 90 mmHg or more, or the person is receiving medication for high blood pressure.

hospitalisation: refers to an episode of care for an admitted patient, which can be a total hospital stay (from admission to discharge, transfer or death) or a portion of a hospital stay beginning or ending in a change of type of care (for example, from acute care to rehabilitation). The same person may have multiple hospitalisations and it is currently not possible to link records of multiple hospitalisations in the AIHW National Hospital Morbidity Database to individuals and therefore to count the number of individuals being hospitalised, and their patterns of hospitalisations. There are 2 distinct types of diagnoses recorded in the database, principal diagnosis and additional diagnosis.

incidence: refers to the number of new cases of an illness, disease, or event occurring during a given period.

Index of Relative Socioeconomic Disadvantage (IRSD): One of the set of Socio-Economic Indexes for Areas (SEIFA) for ranking the average socioeconomic conditions of a population in a geographic area. The IRSD was developed by the ABS for use at Statistical Area Level 2 and summarises attributes of the population that indicate disadvantage, such as low income, low educational attainment, high unemployment and jobs in relatively unskilled occupations.

Indigenous: A person of Aboriginal and/or Torres Strait Islander descent who identifies as an Aboriginal and/or Torres Strait Islander. See also Aboriginal or Torres Strait Islander.

International Statistical Classification of Diseases and Related Health Problems (ICD): The World Health Organization’s internationally accepted classification of death and disease. The 10th Revision (ICD-10) is currently in use. The ICD-10-AM is the Australian Modification of the ICD-10; it is used for diagnoses and procedures recorded for patients admitted to hospitals.

no internet: Access to internet is a measure based on occupied private dwellings. The measure reported is the percentage of occupied private dwellings with no access to internet connection.

no or low English: Proficiency in spoken English is a measure based on self-assessed proficiency level of spoken English by people who speaks other language than English at home. The percentage of people with no or limited proficiency in English is reported.

non-fatal burden: The burden from living with ill-health as measured by years lived with disability. Often used synonymously with years lived with disability.

obesity: marked degree of overweight, defined for population studies as a body mass index of 30 or over.

overcrowding is based on the information collected about the number of bedroom and in a dwelling and the composition of the household. The measure reported in the percentage of household living in a dwelling that requires at least one extra room to meet the minimum housing standard as per the Canadian National Occupancy Standard.

permanent residential aged care: an Australian Government-funded aged care program which provides round-the-clock personal care and nursing services to people living long-term in a residential aged care facility.

prevalence: is the number or proportion of cases or instances of a disease or illness present in a population at a given time. The prevalence of disease is related to both the incidence of the disease and how long people live after developing it (survival).

Primary Health Network (PHN): Primary Health Networks were established by the Australian Government Department of Health on 1 July 2015. These networks are intended to play a critical role in connecting health services across local communities so that patients, particularly those needing coordinated care, have the best access to a range of health care providers, including practitioners, community health services and hospitals. Primary Health Networks work directly with general practitioners, other primary care providers, secondary care providers and hospitals. There are 31 PHNs that cover the whole of Australia.

principal diagnosis: the diagnosis established after study to be chiefly responsible for occasioning the patients hospitalisation.

procedure: a clinical intervention that is surgical in nature, carries a procedural risk, carries an anaesthetic risk, requires specialised training and/or requires special facilities or equipment available only in an acute-care setting.

quintile: A group derived by ranking the population or area according to specified criteria and dividing it into five equal parts. Commonly used to describe socioeconomic areas.

rate: A rate is one number (the numerator) divided by another number (the denominator). The numerator is commonly the number of events in a specified time. The denominator is the population ‘at risk’ of the event. Rates (crude, age-specific and age-standardised) are generally multiplied by a number such as 100,000 to create whole numbers.

remoteness: a system which classifies geographical locations into groups (Major cities, Inner regional, Outer regional, Remote, Very remote) according to distance from major population centres and services. In these analysis, remoteness is based on Accessibility/Remoteness Index of Australia (ARIA) and defined as Remoteness Areas by the Australian Statistical Geographical Standard (ASGS) (in each Census year). Remoteness is a geographic concept and does not take account of accessibility which is influenced by factors such as the socioeconomic status or mobility of a population.

residential aged care facility: these are facilities that provide Australian Government-funded residential aged care either on a permanent or short-term (respite) basis to people. The service must meet specified standards in the quality of the built environment, care, and staffing levels in accordance with the Aged Care Act 1997. Some people refer to these services as ‘nursing homes.’

residential care: A program that provides personal and/or nursing care to people in a residential aged care facility. As part of the service, people are also provided with meals and accommodation, including cleaning services, furniture and equipment.

risk factor: Any factor that represents a greater risk of a health condition or health event.

self-reported: self-reported data rely on survey participants being aware of, and accurately reporting, their health status and health conditions, which is not as accurate as data based on clinical records or measured data. As some people may not be aware that they have the condition estimates based on self-reported data, especially for conditions such as diabetes and chronic kidney disease, may underestimate the prevalence of these diseases. People also underestimate their weight yet overestimate their height, which are used to calculate body mass index for the assessment of overweight and obesity. Measured data are, therefore, more reliable in such instances.

separation (from hospital): An episode of care for an admitted patient, which can be a total hospital stay (from admission to discharge, transfer or death) or a portion of a hospital stay beginning or ending in a change of type of care (for example, from acute care to rehabilitation). Separation also means the process by which an admitted patient completes an episode of care either by being discharged, dying, transferring to another hospital or changing type of care.

Socio-Economic Indexes for Areas (SEIFA): A set of indexes, created from Census data, that aim to represent the socioeconomic position of Australian communities and identify areas of advantage and disadvantage. The index value reflects the overall or average level of disadvantage of the population of an area; it does not show how individuals living in the same area differ from each other in their socioeconomic group. This product presents groups based on the Index of Relative Socio-Economic Disadvantage.

Socio-Economic Indexes for Areas (SEIFA) quintiles: Population-based quintiles are calculated by dividing SEIFA areas into 5 equal groups in such a way that the population in each group is approximately equal. As SEIFA measures the characteristics of an area rather than individuals; the population in the most disadvantaged population-based quintile (‘1 – Lowest’) is 20% of the national population residing in the most disadvantaged areas, rather than the most disadvantaged 20% of the population.

socioeconomic status: The social and economic position of an individual or group within the larger society. In this product, socioeconomic status is reported using one of the Socio-Economic Indexes for Areas – Index of Relative Socio-Economic Disadvantage, typically for 5 groups (quintiles), from the most disadvantaged (lowest socioeconomic status areas) to the least disadvantaged (highest socioeconomic status areas).

statistical areas: A geographical classification defined by the ABS. They encompass four levels, with increasing size and population: Statistical Areas Level 1 (SA1s); Statistical Areas Level 2 (SA2s); Statistical Areas Level 3 (SA3s); and Statistical Areas Level 4 (SA4s).

statistical significance: A statistical measure indicating how likely the observed difference or association is due to chance alone. Rate differences are deemed to be statistically significant when their confidence intervals do not overlap, since their difference is greater than what could be explained by chance.

stroke: occurs when an artery supplying blood to the brain either suddenly becomes blocked or begins to bleed. Stroke often causes paralysis of parts of the body normally controlled by the area affected by the stroke, or speech problems and other symptoms, and is often fatal.

type 2 diabetes: The most common form of diabetes, occurring mostly in people aged 40 and over, and marked by reduced or less effective insulin. See diabetes (diabetes mellitus).

underlying cause of death: the disease or injury that initiated the train of events leading directly to death, or the circumstances of the accident or violence that produced the fatal injury

unemployment is based on the labour status information collected during the census. The measure reported is the proportion of people who are unemployed and looking for full- or part-time work aged 15–64.

usual residence: The area of the address at which the deceased lived or intended to live, for 6 months or more prior to death.