500 likes | 521 Views
The fenoterol story Pharmacoepidemiology Jean-François Boivin 5 November 2010. 1. 2. 3. 4. 5. 6. 7. 8. 9. Lancet – 29 April 1989 – Pages 917 - 922. Source of cases New Zealand National Asthma Mortality Survey 5 – 45 years old Source of controls Hospitalized asthma patients. 10.
E N D
The fenoterol story Pharmacoepidemiology Jean-François Boivin 5 November 2010 1
9 Lancet – 29 April 1989 – Pages 917 - 922
Source of cases New Zealand National Asthma Mortality Survey 5 – 45 years old Source of controls Hospitalized asthma patients 10
Sources of data, asthma treatment Cases: General practioner questionnaires completed for the National Asthma Mortality Survey Controls: Hospital record notes 11
Drug A B SEVERE ASTHMA + Death RR = 0.5 - 1000 10 MILD ASTHMA + Death RR = 0.5 - TABLE 4 A cohort study 100 100 ALL PATIENTS + 202 8 Death RR = 2.5 - 898 102 1100 110 12
Source of cases Death from asthma • National Health Statistics Centre Hospitalized in 12 months before death Source of controls Hospitalized for asthma 14
Source of data, asthma treatment Medical record notes 15
17 NEJM 1992; 326: 501-506
Saskatchewan data bases Saskatchewan Drug Plan Deaths Hospital discharge diagnoses Procedure codes ( e.g.: intubation) Doctor billing codes Use of health services • Hospitalizations • Doctor visits 19
x x 10 prescriptions of asthma drugs death • death certificates • coroner’s reports • autopsy reports • hospital discharge summaries x x 10 prescriptions alive 20
1 year 10 years x x 10 prescriptions of asthma drugs death 1 year 10 years x x 10 prescriptions alive 20
Death rate in study cohort? 1 death 22 person – years ? 1 death 20 person –years ? 21
1 year 10 years x x 10 prescriptions of asthma drugs death 1 year 10 years x x 10 prescriptions alive 22
1 year 10 years x x 10 prescriptions of asthma drugs death 1 year 2 years 10 years x x x 10 prescriptions allergy treatment death 22
1 year 10 years x x 10 prescriptions of asthma drugs death 1 year 2 years 8 years x x x 10 prescriptions allergy treatment death 22
1 death 8 person – years ? Death rate, allergy treatment 1 death 10 person – years ? 1 death 11 person – years ? 23
Example: Time-trend studies Percentage of Children Receiving Measles-Mumps-Rubella (MMR) Immunization in Second Year of Life and Caseload of Children With Autism, by Year of Birth, California, 1980-1994 JAMA. 2001;285:1183-1185 Time Trends in Autism and in MMR Immunization Coverage in California 25
Polio vaccine: Cutter incident Wyeth 26
... . 37
Questions that can be studied with a case -crossover design (Rothman 2002, page 89) Exposure varies from time to time • coffee • exercise One cannot study • blood group • low weight at birth 40
Case cross-over studies Exposure triggers a short-term effect • asthma • sudden death One cannot study • lung cancer • osteoporosis 41
Case cross-over studies Disease must have abrupt onset • allergic reaction • myocardial infarction • car accident One cannot study • multiple sclerosis • hypercholesterolemia 42
Case cross-over studies Effect of exposure must be brief • anxiety in traffic • distraction on cell phone • panic during earthquake One cannot study • sedentarity • personality disorder 43