Epidemiology of Palliative Care/Stats

Question 1

NNT

Answer 1

Number needed to treat - number of patients that would need to be given treatment for one of them to achieve a desired outcome

Question 2

Incidence

Answer 2

Definition: Number of new events/cases of diseases that develop in a population of individuals at risk during a specified time interval

= N of new cases/Total population at risk

Question 3

Prevalence

Answer 3

Definition: Proportion of individuals in a population who have the disease at a specific instant. Provides an estimate of the probability that an individual will be ill at a point in time

= N of cases/Total population at a given point in time

Question 4

Sources of mortality data

Answer 4

1. Death registration systems (COD, typically higher income countries - just 1/3 of world pop)
2. Sample death registration systems (COD, death rates, then extrapolated to cover broader population (includes China and India, with more than 1/3 of world pop)
3. Epidemiological assessments (provide estimates of deaths for major diseases on the basis of incidence/prevalence and mortality rates)
4. Cause of death models (used to estimate deaths according to broad cause groups in regions with non-existent or incomplete mortality data)

Standardised reporting is a barrier, though most have adopted standardised reporting system (e.g. ICD)

Question 5

Life expectancy - factors

Answer 5

• Vary greatly according to resources and social determinants
• Some countries, < 50 years, whereas others it is >70
• Infant mortality has a significant impact on life expectancy

Question 6

Leading causes of death, globally

Answer 6

1. Ischemic heart disease
2. Stroke
3. Lower resp infection
4. COPD
5. Diarrhoeal disease
6. HIV/AIDS
7. Lung CA
8. DM
9. Road injury
10. Prematurity

Question 7

Projections for future leading causes of death

Answer 7

Scenarios:

• Baseline (continues as is)
• Pessimistic
• Optimistic

Factors influencing scenarios:

• Preventative action (e.g. cigarette smoking, obesity, infection control)
• Social and technological factors

Question 8

Place of death data reporting

Answer 8

• Generally only recorded in high income countries
• In low income countries, hospital care is often not available
• In high income countries, about 50% of deaths occur in hospital, though most people indicate a preference for death at home
• Would be helpful to collect large scale data with both “preferred location of death” and “actual location of death”

Question 9

Access to Palliative Care

Answer 9

• Identified as an essential component of health care by the WHO
• To accomplish this, expected that most generalist and specialists will need some training
• Available in most high income countries, with more limited available in middle and low income countries
• In low income countries, most have no access to specialised services, and if they exist, only reach a very small number of people. Majority of dying people are cared for at home by family and neighbours.

Malignant vs non-malignant
- In developed countries, patients dying from illnesses other than cancer are less likely to receive specialist palliative care

Question 10

Methodological Limitations of data relating to symptoms

Answer 10

1. Symptom-related epidemiological data may not reflect the ability of effective symptom management (e.g. saying 70% of patients experience pain does not mean that 70% of patients experience uncontrolled pain)
2. Defining the population from which data are obtained (care must betaken not to extrapolate data beyond the source population - e.g. prognosis data may be gauged from a certain time point that does not apply to the patient in front of you)
3. Patient experience is personal and subjective
   - Difficult to compare studies or pool data as methods of assessment/data collection are not always standardised or consistent
4. Accuracy of data dependent on accuracy of information communicated between the subject and researcher
5. Symptom experience changes over time, as can the burden due to the symptom
   - Studies may not be longitudinal and rater offer point estimates
6. Symptom experience is multidimensional and may be particular to sociocultural characteristics of a particular population
7. Questions still exist regarding the most common or burdensome symptoms/healthcare needs in a particular condition and whether they are properly addressed

Question 11

Four general patterns of functional decline

Answer 11

1. Sudden death (high functional level, until death)
2. Organ failure (stepwise decline in functional level over time until death)
3. Terminal illness (high functional level with steep decline to death)
4. Frailty (middle functional level with slow dwindle downwards to death)