Evidence and ethics: dilemmas of medical prevention

Transkript

1 Evidence and ethics: dilemmas of medical prevention John Brodersen MD, GP, PhD, Associate Professor The Department and Research Unit of General Practice Institute of Public Health, University of Copenhagen

2 External evidence Research question Design What, why, how etc. questions Qualitative study Side-effects/harms Diagnosis Prognosis Cohort or case-control studies Cross sectional study (cohort or observational studies) Cohort study Effect (intervention/treatment) Randomised control trial Overall knowledge Clinical guidelines Systematic review AGREE and GRADE 2

3 Medical Ethics Utilitarianism Deontology First do no harm Autonomy vs. paternalism 3

4 Healthy Primary prevention Secondary prevention Healthy Disease Sick Illness Medicine s perception of sickness Quaternary prevention Tertiary prevention Patient s perception of sickness Sick 4

5 Healthy Primary prevention Secondary prevention Structurally oriented Healthy Disease Sick or Illness Medicine s perception of sickness Individualistic oriented Quaternary prevention Tertiary prevention Patient s perception of sickness Sick 5

6 Balance: benefit & harm Benefit Harm Low risk High risk? 6

7 Healthy Harm Primary prevention Secondary prevention Healthy Disease Sick Illness Medicine s perception of sickness Quaternary prevention Tertiary prevention Patient s perception of sickness Benefit Sick 7

8 Primary medical prevention Individualistic prevention Lifestyle intervention Structurally prevention Vaccination Campaigns 8

9 Individualistic primary prevention Tredive års forskning viser, at massekampagner og individorienteret forebyggelse kun har forbigående og ringe effekt. Man kan ganske enkelt ikke forvente, at borgeren gør det modsatte af, hvad det omkringliggende samfund lægger op til. Torben Jørgensen, Charlotte Glümer, and Charlotta Pisinger. Vi kan lære af fortiden. Nyt om Forebyggelse 15,

10 Individualistic primary prevention Thirty years of research shows that mass-campaigns and individualistic oriented prevention only has transient or nearly no effect. You can simply not expect the citizen to do what the surrounding community suggests. Torben Jørgensen, Charlotte Glümer, and Charlotta Pisinger. [We can learn from the past. News about Prevention] 15,

11 Individualistic primary prevention Når man bygger rulletrapper i stedet for trapper, når der overalt i bybillederne står slik og sodavandsautomater i stedet for frugt, når prisen på tobak og alkohol falder, ja så lægger samfundet op til, at det nemme valg er det usunde valg. Torben Jørgensen, Charlotte Glümer, and Charlotta Pisinger. Vi kan lære af fortiden. Nyt om Forebyggelse 15,

12 Individualistic primary prevention Building escalators instead of stairs. Exposing candy and soft drinks all over the city instead of fruit. Decreasing the price of tobacco and alcohol. All this makes then the unhealthy choice the easy choice. Torben Jørgensen, Charlotte Glümer, and Charlotta Pisinger. [We can learn from the past. News about Prevention] 15,

13 1. prevention: benefit & harm Benefit Harm HPV vaccination to sexual naive Most mass campaigns Flue vaccination Children s vaccination programme Lifestyle intervention 13

14 14

15 15

16 16

17 Secondary medical prevention Individualistic prevention Opportunistic screening Grey-area screening High-risk screening Structurally prevention Mass screening High-risk screening 17

18 Outcome of medical screening Healthy Disease Arbitrary scale 18

19 Variation in a population 19

20 Variation in a population 20

21 Medical screening Benefits Reduced morbidity & mortality Less radical treatment Reassurance normal results Harms Longer morbidity Overdiagnosis and overtreatment False-negative results False-positive results Induced morbidity/mortality 21

22 Overdiagnosis tumour size A B C symptom detection D E F life time and screening intervals Person A gets a false negative screening result because of rapid tumour growth Person B & C are captured with cancer and would have had symptoms before the die Person D is captured with cancer but would not have had symptoms in the remaining life span Person E is never diagnosed with cancer and dies with a cancer Person F is never diagnosed with cancer and there is a spontaneous remission of the cancer 22

23 Mammography screening Esserman L., Shieh Y., & Thompson I. Rethinking Screening for Breast Cancer and Prostate Cancer. JAMA: 302 (15): ,

24 PSA- screening i DK Antal prøver Antal incidente cancer prostata Almen praksis er rekvirent Speciallæge/sygehus er rekvirent Incidente cancer prostatae T. O. Mukai, F. Bro, K. V. Pedersen, P. Vedsted. Brug af undersøgelse for prostataspecifikt antigen. Ugeskr.Laeger 172 (9): ,

25 Cardio-vascular screening % CVD diseases and number of risk factors risk factor 2 risk factors risk factors CVD, diabetes and treated hypertension Age H. Petursson et al. Can individuals with a significant risk for cardiovascular disease be adequately identified by combination of several risk factors? J.Eval.Clin.Pract. 15 (1): ,

26 26

27 J. Brodersen & V. Siersma. Long-term psychosocial consequences of screening mammography. Annals of Family Medicine. 11 (2): ,

28 28

29 Screening: benefit & harm Benefit Harm Cancer screening CRC-screening with sigmoidoscopy? Diabetic retinopathy PKU-screening 29

30 Tertiary medical prevention Individualistic prevention Motivation and resources Risk factors Structurally prevention Strong primary healthcare Continuity in treatment and care 30

31 Tertiary medical prevention Individualistic prevention Risk factors Robust evidence, Motivation and resources Structurally prevention ethically justifiable Strong primary health care Continuity in treatment and care 31

32 3. prevention: benefit & harm Benefit Harm HRT menopause Weight loss, no smoking & exercise among pts with DM, AMI etc. 32

33 Quaternary medical prevention Stop the medical Odyssey for a bio-medical-causality: 10 years at war 10 years to return to home 33

34 Quaternary medical prevention Fibromyalgia Chronic fatigue syndrome Utmattningssyndrom Whiplash MUS Functional Psychosomatic condition Stress 34

35 Quaternary medical prevention Fibromyalgia Chronic fatigue syndrome Lack of evidence, Utmattningssyndrom ethically justifiable Whiplash MUS Functional Psychosomatic condition Stress 35

36 Healthy Healthy Sick Medicine s perception of sickness Quaternary prevention Sick 36 Patient s perception of sickness

37 Curative Medicine Help! 37

38 Preventive Medicine I have something to offer you 38

39 In summary Best available evidence Design depends on research question Which ethical perspective? The person s/patient s preferences Clinical setting/culture 39

40 40

41 Cochrane & Holland "If a patient asks a medical practitioner for help, the doctor does the best possible. The doctor is not responsible for defects in medical knowledge. If, however, the practitioner initiates screening procedures the doctor is in a very different situation. The doctor should, in our view, have conclusive evidence that screening can alter the natural history of disease in a significant proportion of those screened." Validation of screening procedures. Br Med Bull 1971; 27:

42 Brodersen "If a patient asks a medical practitioner for help, the doctor does the best possible. The doctor is not responsible for defects in medical knowledge. If, however, the practitioner initiates preventive procedures the doctor is in a very different situation. The doctor should, in my view, have conclusive evidence that prevention can alter the natural history of disease, and/or reduce morbidity and/or mortality significantly." Svensk Allmänmedicinsk Kongress