Patterns of HIV testing among Ontario physicians, 2006 Claudia Rank, Robert S. Remis, Carol Swantee and Keyi Wu HIV Laboratory, Ontario Agency for Health Protection and Promotion Canadian Association of HIV Research 18 th Annual Scientific Conference Vancouver, BC, April 23-26, 2009
Background: HIV testing in Ontario HIV testing is an important component of public health programs Growing evidence that HIV-infected persons less likely to transmit HIV if aware of serostatus An estimated 30% of HIV-infected persons in Ontario undiagnosed Approximately 1,100 people newly diagnosed with HIV in Ontario each year Strategies for increased uptake of HIV testing include: Anonymous HIV testing (1992) Prenatal HIV testing (1999) HIV testing of immigration applicants (2002) HIV point-of-care testing (2007) Little known about characteristics of physicians who prescribe HIV testing
Annual HIV diagnoses and HIV tests Ontario, 1992-2006 2,000 450,000 1,800 400,000 HIV diagnoses 1,600 1,400 1,200 1,000 800 600 400 200 HIV diagnoses HIV tests 350,000 300,000 250,000 200,000 150,000 100,000 50,000 HIV tests 0 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 Year 2006 0
Study objectives To characterize provider-related factors associated with HIV testing in Ontario Specific objectives were to assess: Frequency of HIV testing among physicians Demographic characteristics and specialty Independent predictors of HIV testing (at least one HIV test/year) Independent predictors of high testing frequency (20 or more HIV tests/year)
Methods Providers identified from HIV test requisitions received at Ontario Public Health Laboratory Jan. 1 Dec. 31, 2006 Physicians linked by name and postal code to database of Ontario physicians (MDSelect version 2006) Probabilistic matching (LinkPlus, Centers for Disease Control and Prevention) Examined distribution of physicians and HIV testing frequency by demographic characteristics and specialty Univariate and multivariate logistic regression analyses using SAS, version 9.1
Results: Ontario physicians 21,041 physicians in Ontario (MDSelect database) Graduated in Canada: 75.9% Male: 68.8% Graduated <1975: 28.1%; 1975-89: 43.7%; 1990-2003: 28.1% Toronto: 33.1%, Ottawa: 11.3%, Northern region: 5.3% Specialty: family medicine, 24.2%; general practice, 23.3%; internal medicine,11.5%; psychiatry, 7.6% 361,609 (87.5%) of 413,048 HIV tests in 2006 linked to a physician in MDSelect 12,477 physicians (59.3%) prescribed at least one HIV test in 2006 HIV tests per physician: mean 29.0, median 10
Proportion of physicians prescribing at least one HIV test by health region, 2006 Northern 69.4% Central East, other 72.4% Eastern, other 55.6% Ottawa 53.7% South West 55.6% Toronto 54.5% p<0.0001 Central West 58.7% p<0.0001
100 90 80 70 60 50 40 30 20 10 0 Proportion of physicians prescribing at least one HIV test by graduation year, 2006 p<0.0001 2000-03 1950-54 1955-59 1960-64 1965-69 1970-74 1975-79 1980-84 1985-89 1990-94 1995-99 Graduation year <1950 Physicians with HIV test (%)
Proportion of physicians prescribing at least one HIV test by specialty, 2006 Specialty HIV testing (%) # tests, mean Family Medicine 86.3% 28.2 Obstetrics/Gynecology 82.1% 64.7 General Practice 80.8% 35.5 Internal Medicine 47.7% 18.8 Pediatrics 37.2% 7.7 Psychiatry 30.1% 3.8
Multivariate analysis: significant predictors of prescribing at least one HIV test (n=21,041) AOR* 95% CI p value Central East, other 1.74 1.59 1.91 <0.0001 Northern 1.40 1.21 1.63 <0.0001 (referent: other regions) Family Medicine/GP 11.2 10.4 12.0 <0.0001 Obstetrics/Gynecology 10.7 8.7 13.2 <0.0001 Internal Medicine 2.08 1.90 2.29 <0.0001 (referent: other specialties) *Model adjusted for graduation year
Physicians and tests by HIV testing frequency Physicians HIV tests HIV tests/physician N (%) N (%) 1 4 4,424 35.5% 8,123 2.3% 5 19 3,994 32.0% 44,435 12.3% 20 99 3,547 28.4% 139,791 38.7% 100 999 483 3.9% 113,534 31.4% 1,000+ 29 0.23% 55,726 15.4% Total 12,477 100% 361,609 100%
Proportion of HIV testing physicians with 20+ HIV tests, by region and specialty Region Proportion (%) Toronto 39.6% Central East, other 37.7% Ottawa 34.7% Other 23.8% Specialty Family Medicine 42.4% General Practice 43.8% Obstetrics/Gynecology 31.7% Internal Medicine 9.9% Other 7.1%
Multivariate analysis: significant predictors of prescribing 20 or more HIV tests (n=12,477) AOR* 95% CI p value Toronto 2.07 1.89 2.26 <0.0001 (referent: other regions) Family Medicine/GP 11.1 9.4 13.0 <0.0001 Obstetrics/Gynecology 6.20 4.87 7.89 <0.0001 Internal Medicine 1.38 1.08 1.77 0.01 (referent: other specialties) *Adjusted Odds Ratio
Physicians with at least one HIV-positive test Overall, 1,048 HIV-positive tests (0.29%) HIV-positivity rate higher among tests prescribed by physicians with: 1-4 tests (0.53%) and 1,000+ tests (0.66%) Internal Medicine specialty (0.73%) 436 physicians (3.5%) had at least one HIV-positive test Toronto (5.5%) Ottawa (4.6%) Northern (1.7%) Other regions (2.0% to 2.7%) HIV-positive tests per physician varied from one to 79 One: 311 physicians (71.3%) Two: 49 physicians (11.2%) Three: 24 physicians (5.5%)
Summary Higher proportion of recently graduated physicians prescribed HIV testing Higher proportion of physicians in Northern or Central East, other regions prescribed HIV testing, but highest testing frequency among those in Toronto Majority (80.7%) who prescribed HIV testing family/general practitioners, internists and obstetrician/gynecologists Most (67.5%) with fewer than 20 tests, but vast majority of HIV tests (85.5%) prescribed by physicians with 20+ tests Proportion of HIV-positive tests higher (0.53%) among physicians with lowest testing frequency (1-4 tests)
Limitations Very high testing frequency (1,000+) may be related to assignment of prescribing physicians Feeder hospitals Tests ascribed to single physician (ie. microbiology department head) 12.5% of HIV tests not linked to physician database MDSelect version 2006 updated to 2003 only 2% of HIV tests submitted by other providers (RN, midwives) HIV tests submitted as part of prenatal screening not included (approximately 140,000 tests in 2006) Unable to analyze patient load or patient-related factors such as proportion of patients at increased risk for HIV infection
Interpretation This study provides valuable data to inform HIV testing policy and continuing medical education Revised HIV testing and counseling guidelines and package to promote HIV testing mailed to ~10,000 providers in May 2008 Lower HIV testing among less recent graduates may reflect undergraduate medical curriculum in recent years; Promotion of HIV testing should be included in continuing medical education Testing patterns should be interpreted in context of proportion of undiagnosed HIV-infected persons to allow efficient targeting of efforts to promote HIV testing Since most physicians did not receive an HIV-positive result, strategies may be necessary to encourage and support HIV testing practices
Acknowledgements Core funding: Ontario HIV Treatment Network AIDS Bureau, Ontario Ministry of Health and Long-Term Care Dalla Lana School of Public Health, University of Toronto Funding for purchase of MDSelect database: AIDS Bureau, Ontario Ministry of Health and Long-Term Care