Patient Characteristics and the Use of Health Care Services by Persons with HIV

1. Patient Characteristics and the Use of Health Care Services by Persons with HIV Esther Hing and Christine Lucas, Ambulatory and Hospital Care Statistics Branch, Division of Health Care Statistics

2. Outline • Esther presents overview of ambulatory medical care surveys • National Ambulatory Medical Care Survey (NAMCS) • National Hospital Ambulatory Medical Care Survey (NHAMCS) • Present selected estimates from these surveys • Methodological challenges associated with ambulatory care HIV/AIDS data • Christine presents overview of National Hospital Discharge Survey (NHDS) • Present trends in inpatient care for HIV/AIDS patients • Methodological challenges associated with inpatient HIV/AIDS data

3. Related NAMCS/NHAMCS/NHDS sessions • Overview of Division of Health Care Statistics • Overview of NAMCS/NHAMCS (20) • Beyond Public-Use Files: Analyzing Protected Data from the NAMCS/NHAMCS (55) • Analyzing Data from the National Hospital Discharge Survey (28)

4. National Ambulatory Medical Care Survey (NAMCS) • Nationally representative survey of patient visits to non-federally employed physicians providing office-based patient care • The NAMCS is a three-stage probability design • 112 National Health Interview Survey primary sampling units (PSUs) • 3,000 -3,700 physicians • 25,00-30,000 visits sampled • 1-week reporting period

5. National Hospital Ambulatory Medical Care Survey (NHAMCS) • Nationally representative survey of visits made to emergency departments (EDs) and outpatient departments (OPDs) of non-Federal, short-stay hospitals • The NHAMCS is a four-stage probability design • 112 NHIS PSUs • 500 hospitals • 400 EDs and 280 OPDs • 35,000 ED visits and 35,000 OPD visits • 4-week reporting period.

6. NAMCS and NHAMCSData • NAMCS and NHAMCS are record-based surveys • Data abstracted from the patient’s medical record by the physician and/or office or hospital staff, or interviewer • Estimates are in terms of visits, not patients

7. NAMCS and NHAMCSData • NAMCS/NHAMCS provide information from the clinician’s perspective • Diagnoses and services provided have high validity • Data less subject to respondent recall • Public use files released on the internet include input statements to assist users creating files in SAS, SPSS, and STATA software

8. Content of NAMCS and NHAMCS • Data collection instrument: Patient Record form (PRF) • PRFs are revised periodically • Items collected every year include demographics, payment source, reason for visit, diagnoses, services received, medications, providers seen, and disposition • Diagnostic and therapeutic services, and other data items, may change with each PRF revision

9. Content of NAMCS and NHAMCS • Physician diagnoses • HIV present (NAMCS/OPD:1993-94) • HIV/AIDS present (NAMCS/OPD:1995-96) • HIV serology blood test (NAMCS:1989-2000, OPD:1992-2000, ED:1992-present) • Medications prescribed or ordered • HIV transmission counseling (NAMCS:1989-90,1993-1996, OPD:1993-1996) • HIV/STD prevention education (NAMCS/OPD:1997-98)

10. Percent distribution of ambulatory visits with HIV/AIDS as primary diagnosis by setting: 2005-06 55.5 43.4 * NOTE: Percentages based on average 2,818,000 visits with ICD-9-CM codes 042, V08. * Figure does not meet standards of reliability or precision.

11. Percent of visits with diagnosed HIV/AIDS and antiretroviral drugs ordered or prescribed by setting: 2006 48.9 45.4 44.3 NOTE: Percentages based on 2,920,600 visits with ICD-9-CM codes 042, V08. * Figure does not meet standards of reliability or precision.

12. Office visits where medical record indicates patient currently has HIV or HIV/AIDS: 1993-96 1,974 1,565 1,343 1,155

13. HIV/AIDS prevention counseling among visits with tests for HIV or sexually transmitted diseases (STD):1997-98 Source: “HIV and STD counseling among visits with HIV/STD testing at physician offices and hospital outpatient departments” Tao, Branson, Anderson, Irwin, 2003.

14. Methodological Challenges • Although NAMCS/NHAMCS data may be used to analyze visits by patients with HIV/AIDS, data items collected on HIV serology testing and HIV transmission counseling are not collected every year and wording changes may affect estimates • MULTUM therapeutic categories (175,176) identifies antiretroviral drugs in 2006 data for the first time • NDC (National Drug Code) therapeutic classification used in years prior to 2006 did not identify antiretroviral drugs; MULTUM categories can be applied to drug data prior to 2006 using information available at our website (www.cdc.gov/nchs/ahcd/ahcd1.htm).

15. Methodological Challenges (cont.) • HIV/AIDS patient visits (roughly 3 million annually) are rare among 1 billion ambulatory visits to physician offices and hospital outpatient departments; even rarer among ED visits • Need to combine at least two years of data to get reliable estimates • More years are needed for more detailed analysis

16. National Hospital Discharge Survey (NHDS) Survey Years • Conducted annually 1965-present • Latest data available: 2006 • 2007 data will be available Winter 2008 • HIV data from mid-1980’s to present

17. NHDS Survey Design • National probability sample: • Short stay, non-Federal hospitals • General hospitals or children’s general hospitals • Three-stage design: • Geographic areas • Hospital • Discharge

18. Data Collected in the NHDS • Medical Data • Diagnoses and procedures • Additional Variables • Patient demographics • Days of care • Month of discharge • Diagnosis-related Group (DRG)

19. HIV data in the NHDS reflect discharges with at least one of the following International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) Codes • Prior to 1995 • 042-044 Human Immunodeficiency Virus [HIV] disease • 279.19 Disorders involving the immune mechanism: Other • 795.8 Positive serological or viral culture findings for human immunodeficiency virus (HIV) • Beginning in 1995 • 042 Human Immunodeficiency Virus [HIV] disease • V08 Asymptomatic human immunodeficiency virus [HIV] infection status

20. Number of discharges from short-stay hospitals with human immunodeficiency virus diagnosis: United States, selected years, 1990, 1995, 2000, 2005, and 2006 Source: National Hospital Discharge Survey, Annual Files 1990-2006

21. Number of discharges from short-stay hospitals with human immunodeficiency virus diagnosis, by sex: United States, selected years, 1990, 1995, 2000, 2005, and 2006 Source: National Hospital Discharge Survey, Annual Files 1990-2006

22. Number of discharges from short-stay hospitals with human immunodeficiency virus diagnosis by age: United States, selected years, 1990, 1995, 2000, 2005, and 2006 Source: National Hospital Discharge Survey, Annual Files 1990-2006

23. Rates of discharges from short-stay hospitals with human immunodeficiency virus diagnosis by region: United States, selected years, 1990, 1995, 2000, 2005, and 2006 Source: National Hospital Discharge Survey, Annual Files 1990-2006

24. Strengths and Challenges of the NHDS HIV Data • Strengths • Trend data • Large sample size • Records based • Challenges • Discharges, not patients • Maximum of 7 diagnoses per discharge

25. National Hospital Discharge Survey (NHDS)Website and Other Information • Go to the Hospital Discharge and Ambulatory Surgery homepage on the Web: http://www.cdc.gov/nchs/about/major/hdasd/nhds.htm • For more information on HIV/AIDS http://www.cdc.gov/hiv/ • For a copy of this presentation clucas3@cdc.gov