Burden of Disease Research Unit

1. Burden of Disease Research Unit WHO-FIC Collaborating Centre (Under designation) Cause of death statistics from vital registration Debbie Bradshaw

2. Outline of presentation • Illustrate the public health value of cause of death statistics – City of Cape Town • Process of collecting cause of death statistics • ascertaining the cause of death • underlying cause of death • ICD coding • cause of death statistics • Quality of cause of death certification

4. Cause of death profile in Cape Town, 2004 Source: Western Cape BOD project using City of Cape Town mortality data

5. Age specific HIV death rates, Cape Town 2001 - 2006 Source: Western Cape BOD project using City of Cape Town mortality data

6. Age-standardised death rates (per 100 000 population) Cape Town, 2001 – 2006 Source: Western Cape BOD project using City of Cape Town mortality data

7. Age-standardised death rates (per 100 000 population) by broad cause for sub-districts of Cape Town, 2006 Source: Groenewald et al, 2008

8. Leading causes of premature mortality, Cape Town 2006 Percentage of total Years of Life Lost (YLLs) Source: Western Cape BOD project using City of Cape Town mortality data

9. Public health importance of mortality data • Monitor the health of the population • Leading causes of death • Mortality rates (geographic variations) • Trends over time • Inform decisions about health policy and strategy • Prevent premature deaths • Service provision • Health budgets • Evaluate health service outcomes

10. Main stages in production of cause of death statistics Attending doctor: • Establish diagnosis • Complete death certificate (International form – WHO) Coding by Statistical Office: • Code causes of death (ICD code for each cause listed) • Classify cause of death (select a single underlying cause of death for stats according to ICD selection rules) • Check validity, query Analysis by Statistical Office: • Tabulate and disseminate data Source: Adapted from Johansson LA, 2008

12. Immediate cause on top line Any causal sequence with underlying cause at the bottom Contributing cause but not in causal sequence in Part 2

13. According to ICD-10: • The Immediate Cause is the final disease, injury or complication directly causing the death. It should be noted that the mechanism of death or terminal event (for example, cardiac arrest or respiratory arrest) is not considered to be a cause of death. The mechanism of death should not be reported as the immediate cause of death as it is a statement not specifically related to the disease process, and it merely attests to the fact of death. • The Underlying Cause of Death is the disease or injury that started the sequence of events leading directly to death or the circumstances of the accident or violence that produced the fatal injury. In the case of a violent death, the form of external violence or accident is antecedent to the injury entered, although the two events may be almost simultaneous. • Part II is for reporting all other significant diseases, conditions, or injuries that contributed to death but which did not result in the underlying cause of death given in Part I.

14. A 75-year-old female had a 15-year history of non-insulin-dependent diabetesmellitus, a 13-year history of mild hypertension treated with thiazide diuretics, and an uncomplicated myocardial infarction 6 years prior to the present illness. She was found disoriented at her home and brought to hospital. On admission she was noted to be unresponsive, without focal neurologic signs, and severely dehydrated with a blood pressure of 90/60. Initial laboratory tests disclosed severe hyperglycemia, hyperosmolarity, azotemia, and mild ketosis without acidosis. A diagnosis of hyperosmolar nonketotic coma was made. The patient was treated with fluids, electrolytes, insulin and broad-spread antibiotics. Within 72 hours, the patient’s hypersomolar, hyperglycemic state was resolved. However, she remained anuric with progressive azotemia. The patient died on the 8th hospital day in severe renal failure.

15. Acute renal failure 5 Days Hyperosmolar nonketotic coma 8 Days Diabetes mellitus, non-insulin dependent 15 Years Hypertension, Previous myocardial infarction

16. Female aged 77 years, stumbled and fell over while cleaning the house and sustained a fracture of the neck of the left femur. She had an operation for insertion of a pin the following day. Four weeks later her condition deteriorated, she developed hypostatic pneumonia and died two days later.

17. Terminal Hypostatic Pneumonia 2 Days Fractured Left Neck of Femur 4 weeks Accidental fall while cleaning at home 4 weeks

18. Cancer Diabetes

19. Stroke Pneumonia

20. Cardiac arrest

21. Terminology Nothing! Cardio-Respiratory Arrest

22. Terminology that should be avoided • Ill-defined / non-specific conditions • Old age • Headache • “Natural causes” • Mechanisms of death • Heart failure • Kidney failure • Dehydration • Hypoxia • Sepsis

23. Things that should not be on the certificate • Abbreviations • DM II • MI • MS • HONK • Stories • The patient presented three days ago with severe abdominal pain, but the family says it’s been going on for a long time. At surgery extensive peritoneal sepsis of unknown cause was found.

24. Things that should not be on the death certificate Nothing! zxcv uiodsa bhcox;

25. In the case of Human Immunodeficiency Virus • Check hospital notes for HIV-tests or treatment • Underlying COD: Human immunodeficiency virus • Intermediate COD: Acquired Immunodeficiency syndrome • Immediate COD: Tuberculosis / Cryptococcal Meningitis, etc.

26. Processing information from the medical certificate • Code each cause according to the International Statistical Classification of Diseases and Related Health Problems (ICD-10) • Apply ICD-10 rules to establish the Underlying cause of death • Check the validity of the information – and query or correct • Check consistency of data eg prostate cancer for female

27. http://www.who.int/classifications/icd/en/

28. ICD – 10 A00 Cholera A00.0 Cholera due to Vibrio cholerae 01, biovar cholerae A00.1 Cholera due to Vibrio cholerae 01, biovar eltor A00.9 Cholera, unspecified Z99 Dependence on enabling machines and devices, not elsewhere classified Z99.0 Dependence on aspirator Z99.1 Dependence on respirator Z99.2 Dependence on renal dialysis Z99.3 Dependence on wheelchair Z99.8 Dependence on other enabling machines and devices Z99.9 Dependence on unspecified enabling machine and device

29. A00 – B99 Certain infectious and parasitic diseases C00 – D48 Neoplasms D50 – D89 Diseases of the blood and immune mechanism E00 – E90 Endocrine, nutritional and metabolic disorders F00 – F99 Mental and behavioural disorders G00 – G99 Diseases of the nervous system H00 – H59 Diseases of the eye and adnexa H60 – H95 Diseases of the ear and mastoid process I00 – I99 Diseases of the circulatory J00 – J99 Diseases of the respiratory diseases K00 – K93 Diseases of the digestive system L00 – L99 Diseases of the skin and subcutaneous tissue M00 – M99 Diseases of the musculoskeletal system N00 – N99 Diseases of the genitourinary system O00 – O99 Pregnancy, children and puerperium P00 – P99 Perinatal conditions Q00 – Q99 Congenital malformations R00 – R99 Symptoms and signs not elsewhere defined S00 – T99 Nature of injury V01 – Y98 External causes of morbidity and mortality Z00 – Z99 Reasons for encounter with health service ICD – 10Chapters

30. Problems with cause of death statistics Errors can occur at all stages of production: • Diagnosis • Death certification • Errors (mechanism of death/no UC, competing causes, incorrect sequence) • Insufficient information • Coding • Classification (incorrect or inconsistent application of ICD selection rules) • Analysis

31. Source: Groenewald et al, 2005

32. Death certification quality in Cape Winelands and Overberg:Percentage ill-defined causes of death by sub-district

33. Review of certificates in Vangaurd: Major errors 28.7% 15.3% 14.8% 13.5% 43.4% • Incorrect sequencing in Part 1 • Competing causes of death in Part 1 • Lack of a proper underlying cause of death • A mechanism of death, without an underlying cause of death • One or more major errors in DNF Source: Burger et al., 2007

34. Review of certificates in Vangaurd : Minor errors 81.5% 23.7% 13.0% 2.5% 86.1% • Absence of a time estimate between onset of disease and death • Use of abbreviations • Recording of inappropriate information • Illegible handwriting • One or more minor errors in DNF Source: Burger et al., 2007

35. In total 91,7% of cases had at least one error!!

36. Serious major errors and associated factors, Academic Hospital in Cape Town Source: Nojilana et al., 2008

37. 242 Potentially HIV/AIDS related causes* not tested for HIV Tested for HIV HIV +ve HIV -ve 17 15 32 6 71 0 6 33 38 recorded on death certificate not recorded on death certificate not reported on death certificate recorded on death certificate HIV test information from medical record for sub-sample

39. Brief intervention for internsProportion with adequate score Source: Pieterse et al., 2008

40. http://who.int/bookorders www.healthmetricsnetwork.org healthmetrics@who.int

41. Domains of Measurement Determinants of Health Socio-economic and demographic factors Environmental and behavioural risk factors Service seeking behaviours Health status Mortality Morbidity/ Disability Well-being Health System Inputs Outputs Outcomes Policy Information Coverage Financing Service Utilisation Human resources (availability Organisation and quality) Source: Health Metrics Network

42. http://www.who.int/classifications/icd/en/

43. Acknowledgement BOD Unit and collaborators Dr Pam Groenewald Dr Lene Burger Ms Desiree Pieterse Ms Beatrice Nojilana WHO-FIC Collaborating Centre Ms Lyn Hanmer Dr Pam Groenewald Mr Malute Tshivase Ms Margie Schneider Prof Jenny Jelsma Mr David Bourne Me Sedick Isaacs Local, provincial and national government City of Cape Town Western Cape Department of Health Department of Home Affairs Statistics South Africa