Principals of Birth Defects Surveillance

Transcription

1 Principals of Birth Defects Surveillance Hani K. Atrash, MD, MPH Associate Director for Program Development National Center on Birth Defects and Developmental Disabilities Centers for Disease control and Prevention Meeting on the Impact of Surveillance Systems on Health Care in Lebanon and the Region Beirut, Lebanon May 12-13, 2006 Promoting the health of babies, children, and adults, and enhancing the potential for full, productive living 1

2 Outline Definitions Planning a surveillance system The Metropolitan Atlanta Congenital Defects Program (MACDP) 2

3 Surveillance Close watch kept over someone or something 3

4 Public Health Surveillance Close watch kept over public health conditions or indicators 4

5 Public Health Surveillance The ongoing, systematic, collection, analysis, and interpretation of health data essential to the planning, implementation, and evaluation of public health practice, closely integrated with the timely dissemination of these data to those who need to know. The final link of the surveillance chain is the application of these data to prevention and control. A surveillance system includes a functional capacity for data collection, analysis, and dissemination linked to public health programs. 5

6 Public Health Surveillance The ongoing, systematic collection, analysis, and interpretation of health data. 6

7 Public Health Surveillance The ongoing, systematic collection, analysis, and interpretation of health data essential to the planning, implementation, and evaluation of public health practice.. 7

8 Public Health Surveillance The ongoing, systematic collection, analysis, and interpretation of health data essential to the planning, implementation, and evaluation of public health practice closely integrated with the timely dissemination of these data to those who need to know. 8

9 Public Health Surveillance The ongoing, systematic collection, analysis, and interpretation of health data essential to the planning, implementation, and evaluation of public health practice closely integrated with the timely dissemination of these data to t those who need to know. The final link of the surveillance chain is the application of data to prevention and control. 9

10 Public Health Surveillance The ongoing, systematic, collection, analysis, and interpretation of health data essential to the planning, implementation, and evaluation of public health practice, closely integrated with the timely dissemination of these data to those who need to know. The final link of the surveillance chain is the application of these data to prevention and control. A surveillance system includes a functional capacity for data collection, analysis, and dissemination linked to public health programs. 10

11 Surveillance Cycle Data Planning Collection Analysis Statistics Interpretation Information Policy Analysis Evaluation Action Recommendations Dissemination 11

12 Public Health Surveillance is a component of Public Health Practice 12

13 Public Health Surveillance Surveillance in Public Health Practice Public health practice includes: surveillance, research, service, and training Surveillance must not be equated with epidemiologic investigations and research Surveillance is used to identify research and service needs, which in turn, help to define training need 13

14 Planning a Surveillance System? Establish the objectives Determine health events that need surveillance Develop the methods: Case definitions Data collection: sources, mechanisms Data-collection instruments Field-testing of methods Analytic approaches Interpretation and dissemination Evaluation Assure use of analysis and interpretation Evaluate the system Ethical and legal issues 14

15 Public Health Surveillance Public health surveillance data can be used for: Estimating the magnitude Studying trends and natural history Detecting clusters and epidemics Documenting the epidemiology Facilitating research Testing hypothesis Evaluation control and prevention measures Monitoring changes in agents causing disease or injury Detecting changes in health practice Planning intervention programs Objectives 15

21 Why Conduct Surveillance of Birth Defects? Birth Defects is an Important public Health Problem: 1 in every 33 babies is born with a major birth defect each year >120,000 babies born with BD in the US every year >5,600 infant deaths; Leading cause of infant mortality 30% of admissions to pediatric hospitals 17 most significant birth defects: $8 billion annually Some causes entirely preventable 21

22 Purposes of a Birth Defects Surveillance Program Detect time trends, epidemics Quantify morbidity or mortality Evaluate community concerns Stimulate epidemiological research Evaluate the need for and facilitate access to services Guide and assess the progress of intervention and prevention Provide information for education and advocacy 22

23 Data Sources for Surveillance Vital Records Review medical records Administrative databases Special Data Sources Prenatal Diagnosis Centers Clinical Examination 23

24 Rates of Major Birth Defects By Data Source Method and Source Rate Birth Certificates* 1.5% Newborn hospital discharge % Mandatory hospital reporting 3.4% Active hospital surveillance 3.2% Physical exam of infants 8.3% * Birth Certificates Florida 1996 New York MACDP Collaborative Perinatal Project

25 Metropolitan Atlanta Congenital Defects Program One of the nation s oldest population-based birth defects surveillance systems Established in 1967 in collaboration with Emory University and the Georgia Mental Health Institute following the Thalidomide tragedy Currently administered by CDC s National Center on Birth Defects and Developmental Disabilities (NCBDDD) 25

26 Metropolitan Atlanta Congenital Defects Program Objectives: Monitor births for changes in incidence and unusual patterns Develop and maintain a case registry for use in epidemiologic and genetic studies Quantify the morbidity and mortality associated with birth defects Provide data for education and health policy decisions leading to prevention 26

27 Metropolitan Atlanta Congenital Defects Program Population: All births occurring in the five metropolitan Atlanta area In 1968: 26,000 births and 587 cases In 2000: 50,000 births and 1,500 cases Population composition changed over time: 1968, 27% blacks; 2000, 48% blacks 27

28 Metropolitan Atlanta Congenital Defects Program Case definition: Mother resides in the 5 county area at time of delivery Baby has a serious or major structural defects that can have adverse effects on health or development Ascertainment made by 6 years of age; and, Gestational age of 20 weeks or more Prenatally ascertained cases analyzed separately Cases do not include: functional or metabolic disorders, hematologic disorders, minor defects and normal variants 28

29 Metropolitan Atlanta Congenital Defects Program Case Ascertainment - 1: Trained abstractors actively search newborn hospitals, pediatric hospitals and other sources Use of multiple sources ensures: More complete case recording More precise and accurate diagnosis Availability of maternal and infant data Ease for conducting follow-up studies 29

30 Metropolitan Atlanta Congenital Defects Program Case Ascertainment - 2: At newborn hospitals abstractors review: Newborn hospital logs: Obstetric logs Newborn nursery logs Neonatal intensive care unit logs Postmortem logs Surgery records Prompts for in-depth review include: birth defects, preterm infant, low birthweight infant, stillbirth, neonatal death, newborn surgery, and all newborns in high risk or special care nurseries 30

31 Metropolitan Atlanta Congenital Defects Program Case Ascertainment - 3: At Pediatric hospitals: Abstractors review: Computerized discharge records Surgery records Pathology records Prompts for in-depth review: Any mention of birth defects 31

32 Metropolitan Atlanta Congenital Defects Program Case Ascertainment - 4: At Georgia Department of Human Resources: Abstractors review: Birth certificates Fetal death certificates Death certificates Pathology reports of pregnancy terminations Abortion records Autopsy records Records of cytogenic laboratories 32

33 Metropolitan Atlanta Congenital Defects Program Data Collection: Use special forms to collect the following information: Identifying information Demographic information Diagnostic information Pregnancy information Outcome information Hospital and physician information 33

34 Metropolitan Atlanta Congenital Defects Program Coding and Classification: For each infant, information is collected on up to 24 individual defects Defects are coded using a modified British Pediatric Association (BPA) six digit code (BPA 79) Over 100 defects are monitored by MACDP All case abstracts are evaluated by a clinical geneticist or a dysmorphologist for accuracy and completeness of diagnosis 34

35 Metropolitan Atlanta Congenital Defects Program Quality Control: Evaluates completeness and accuracy Various approaches used: Re-abstraction of records Reviews of new computerized discharge summary indices Linkages with prenatal records Special projects: capture-recapture method estimated case ascertainment at 87% at one year and 95% at 2 years 35

36 Metropolitan Atlanta Congenital Defects Program Data Analysis and Dissemination: Data analyzed quarterly for changes in birth defects rates Observed numbers are compared to expected numbers based on prevalence data during the past 2 years Regularly provides information to local and state health officials and to national and international programs: NBDPN, International Clearinghouse for Birth Defects Surveillance Systems (35 programs) 36

37 Metropolitan Atlanta Congenital Defects Program Results Surveillance: Almost 40,000 babies with serious BD identified Served as a model for other surveillance systems of adverse reproductive outcomes: MADDSP, FASSNet Developed tools and methodology to support surveillance systems in the US and internationally Documented trends in a number of BDs, e.g: Declines in NTD Increase in hypospadias Increase in heart defects Decline in congenital rubella syndrome Provided baseline information for comparison studies in special populations, e.g, Vietnam veterans, pregnant women 37

38 Metropolitan Atlanta Congenital Defects Program Results Epidemiology - 1: Serves as a source of case data for many follow up studies Multiple epidemiologic studies on BDs and etiologic factors: Phecomelia and tricyclic antedepressents (72, no relationship) Spray adhesives (73, no increase in BD with increased sales) Diazepam and cleft lip (75, possible association) Water floridation and BD (76, no association) Airport noise and BD (79, no association) Maternal fever and NTD (80, findings support association) Vietnam veterans and BD (84, no association) Periconceptional multivitamins and NTD (88, reduction among users) Maternal rubella and BD (89, decline in congenital rubella) Maternal diabetes and BD ( 90, association with several defects) 38

39 Metropolitan Atlanta Congenital Defects Program Results Epidemiology - 2: Epidemiologic studies: Anesthesia and BD (94, no association) Chorionic villus sampling and transverse digital deficiency (95, an association) Impact of prenatal diagnosis on prevalence of BD (95, decrease in at birth prevalence of anencephaly) Periconceptional multivitamins and heart defects (96, reduction in conotruncal defects) Maternal obesity and NTD (96, possible association) Maternal smoking, family history and club foot (00, possible gene-environment interaction) Periconceptional multivitamins and orofacial clefts (01, possible reduction in risk) 39

40 Metropolitan Atlanta Congenital Defects Program Results - Prevention: Multivitamins and reduction in NTD led to studies on folic acid and recommendations for folic acid fortification and supplementation Chorionic villus sampling and 6 times increase in transverse limb reduction led to recommendation to counsel women considering prenatal diagnosis 40

41 NCPNN: Is There a Place for Birth Defects Surveillance? What Will it Take? Existing system with: Identified partners Well defined population Link to research Link to clinical practice Link to public health practice? Link to training? Dissemination and communication to those who need to know? Evaluation and quality assurance? 41

42 Thank You! 42