1. Prognosis HINF 371 - Medical Methodologies Session 9

2. Objective Understand prognosis and factors determining prognosis Understand prognosis and factors determining prognosis Review PRO-Act-Ive over a case Review PRO-Act-Ive over a case

3. Reading Mar CD, Doust J, Glasziou (2006) Chapter 5: Fine Art of Prognostication, in Clinical Thinking: Evidence, Communication and Decision-Making, Blackwell Publishing and BMJ Books, USA Mar CD, Doust J, Glasziou (2006) Chapter 5: Fine Art of Prognostication, in Clinical Thinking: Evidence, Communication and Decision-Making, Blackwell Publishing and BMJ Books, USA Mar CD, Doust J, Glasziou (2006) Chapter 6: Making Clinical Management Decisions, in Clinical Thinking: Evidence, Communication and Decision- Making, Blackwell Publishing and BMJ Books, USA Mar CD, Doust J, Glasziou (2006) Chapter 6: Making Clinical Management Decisions, in Clinical Thinking: Evidence, Communication and Decision- Making, Blackwell Publishing and BMJ Books, USA http://www.cdc.gov/nchs/products/pubs/pubd/lftbl s/life/1966.htm http://www.cdc.gov/nchs/products/pubs/pubd/lftbl s/life/1966.htm http://www.cdc.gov/nchs/products/pubs/pubd/lftbl s/life/1966.htm http://www.cdc.gov/nchs/products/pubs/pubd/lftbl s/life/1966.htm

4. Prognosis Each condition have their own natural progression Each condition have their own natural progression Our decision is what would happen if we did nothing Our decision is what would happen if we did nothing If an intervention is recommended, then what are the options If an intervention is recommended, then what are the options Which options are preferrable by the patient Which options are preferrable by the patient

5. Comparison of life expectancies Age Numb er of surviv ors Number of people dying before the next age The proportio n surviving The proportio n of dying before next age Coefficien t of variation Number of life years lived Number of life years lived beyond Life expectan cy at age Coefficient of variation of life expectancy Males-22Males-7998,865 5732494 3185 0.99905 0.94444 0.00095 0.05556 19.6 3.7 98818 55731 5620852 503092 56.85 8.78 0.15 0.77 Females-22Females-7999,224 7126140 2481 0.99960 0.96519 0.00040 0.03481 30.7 4.0 99203 70020 6096433 760225 61.44 10.67 0.14 0.59

6. What is the big deal? We will all die anyway. Median Absolute risk difference in Mortality or survival Rule of Thumb: Mortality doubles every 6 years

7. But we are able to make changes for our prognosis

8. Determining Prognosis Estimating the severity of illness Estimating the severity of illness Likely duration of the illness to date Likely duration of the illness to date Extrapolate forward in future Extrapolate forward in future Independent factors – Age, physical condition Independent factors – Age, physical condition Dependent factors – estrogen receptors in breast cancer, smoking in COPD Dependent factors – estrogen receptors in breast cancer, smoking in COPD Risk factors – susceptability to disease – systemic Lupus Erythematosus Risk factors – susceptability to disease – systemic Lupus Erythematosus

9. Patterns of Diagnosis Spontaneously remitting: cold, sprain, Spontaneously remitting: cold, sprain, Recurrent – intermittent: migraine, asthma Recurrent – intermittent: migraine, asthma Chronic (non-progressive): ulcerative colitis, rheumatoid arthritis, anxiety Chronic (non-progressive): ulcerative colitis, rheumatoid arthritis, anxiety Progressive: COPD, cancers, Progressive: COPD, cancers,

10. Use of Pro-Act-Ive Case Madison is 22-month-old girl who has been unwell for the past 48 hours. She has been unhappy, crying occasionally, has a fever, is not eating or drinking well and is waking up and crying several times through the night. She has two older siblings, who are at primary school and are well. Both parents work full-time and she goes to child-care centre near her mother’s work on weekdays. Madison has generally been a well child, but she had a similar episode about 6 months ago that took a week to resolve. Her immunization is up-to-date. On examination, she is not dehydrated, her temperature is 37.8 degrees and the only abnormality of note is a right dull red tympanic membrane.

11. Problem and Reframing P=define the problem P=define the problem Unhappy child, sick and probably ottis media Unhappy child, sick and probably ottis media R=reframe the problem R=reframe the problem Family is sleepless Family is sleepless Mother works casually, can’t earn money if can’t go to work or needs to pay for child care Mother works casually, can’t earn money if can’t go to work or needs to pay for child care Mother worried about hearing loss or limitations in language development Mother worried about hearing loss or limitations in language development Wants solutions to eliminate these episodes Wants solutions to eliminate these episodes Disease is self-limiting, may have complications of infection of nearby bones or tissues, in chronic state may create hearing loss Disease is self-limiting, may have complications of infection of nearby bones or tissues, in chronic state may create hearing loss Parents probably expect antibiotics – but problems with over use of antibiotics Parents probably expect antibiotics – but problems with over use of antibiotics

12. Objectives Minimize symptoms Minimize symptoms Minimize duration of illness Minimize duration of illness Reduce risk of complications Reduce risk of complications Reduce the risk of spread of the illness to other family members Reduce the risk of spread of the illness to other family members Reduce the use of antibiotics Reduce the use of antibiotics

13. Act A=consider all alternatives A=consider all alternatives Do nothing Do nothing Provide pain relief Provide pain relief Provide antibiotic Provide antibiotic Provide prescription and let family decide Provide prescription and let family decide Seek further solutions e.g. myringotomy Seek further solutions e.g. myringotomy

14. Act Consider consequences of each alternative and estimate the changes Consider consequences of each alternative and estimate the changes Asked focussed question Asked focussed question Patient Patient Intervention Intervention Comparator Comparator Outcome Outcome Search for evidence (Medline, Cochrane Library, Clinical evidence by BMJ, UpToDate) Search for evidence (Medline, Cochrane Library, Clinical evidence by BMJ, UpToDate) Appraise the evidence Appraise the evidence Apply evidence to the individual patient Apply evidence to the individual patient Evaluate the process Evaluate the process What is the effect of antibiotics compared with nothing on pain in a 2 year old with acute otitis media

15. Apply evidence to the patient Determine the possible beneficial and harmful effects of treatment Determine the possible beneficial and harmful effects of treatment Antibiotics – some reduction of pain 2-7 days, no change in 24 hrs 7 percent absolute reduction, 30 percent relative risk reduction, 67 percent relative risk, number needed to treat 14. Antibiotics – some reduction of pain 2-7 days, no change in 24 hrs 7 percent absolute reduction, 30 percent relative risk reduction, 67 percent relative risk, number needed to treat 14. No effect on risk of occurrence, ear perforation, abnormal hearing, No effect on risk of occurrence, ear perforation, abnormal hearing, Side effects of antibiotics: vomiting, diarrhoea, allergic reaction, antibiotic resistance – 1 every 17 Side effects of antibiotics: vomiting, diarrhoea, allergic reaction, antibiotic resistance – 1 every 17 Determine if there is a predictable variation in the relative effects of treatment between sub-group of patients Determine if there is a predictable variation in the relative effects of treatment between sub-group of patients Younger children <2 years Younger children <2 years Children otitis media at both sides Children otitis media at both sides Seriously unwell (e.g. high fewer) Seriously unwell (e.g. high fewer) Examine if effects vary with risk level Examine if effects vary with risk level Indigenous communities Indigenous communities Estimate the predicted benefits and harms for an individual patient Estimate the predicted benefits and harms for an individual patient Maddison is <2 years Maddison is <2 years But has low risk of pain But has low risk of pain

16. Trade-offs T: Identify Trade-offs T: Identify Trade-offs Pain is the only problem Pain is the only problem Illness complications are quite low Illness complications are quite low Antibiotic versus ordinary pain killers Antibiotic versus ordinary pain killers Antibiotic resistance versus pain Antibiotic resistance versus pain

17. Ive I: integrated the evidence and the values I: integrated the evidence and the values The evidence doesn’t identify significant benefits for antibiotic use The evidence doesn’t identify significant benefits for antibiotic use But mother may be happy that antibiotics is prescribed But mother may be happy that antibiotics is prescribed V: optimize the expected value V: optimize the expected value No alternative is optimal No alternative is optimal Maddison is <2 but not seriously unwell. Maddison is <2 but not seriously unwell. E: explore assumptions and evaluate uncertainty E: explore assumptions and evaluate uncertainty How certain we are about the estimates of benefit and harm How certain we are about the estimates of benefit and harm What would be the effect of variation – sensitivity analyses What would be the effect of variation – sensitivity analyses

18. Heuristics of case Overall few short-term benefits and no long-term benefit of antibiotics for otitis media. Major problem is increase in antibiotic resistance. Not wise to prescribe antibiotics Overall few short-term benefits and no long-term benefit of antibiotics for otitis media. Major problem is increase in antibiotic resistance. Not wise to prescribe antibiotics Pain killers may be able provide same short-term benefits with fewer potential harms Pain killers may be able provide same short-term benefits with fewer potential harms Some children may benefit from antibiotics – high risk of complications, indigenous children, seriously unwell children with bilateral illness, high fewer. Some children may benefit from antibiotics – high risk of complications, indigenous children, seriously unwell children with bilateral illness, high fewer.

19. What would you do?