From the *The Kirby Institute, The University of New South Wales; †East Sydney Doctors, Sydney, New South Wales, Australia; ‡Melbourne School of Population Health, The University of Melbourne, Melbourne; and §Melbourne Sexual Health Centre, The Alfred Hospital, Carlton, Victoria, Australia
Contributors: D.B. was responsible for the overall management of the clinic intervention. D.C. in consultation with R.G. carried out the statistical analysis. R.G. devised the original idea for the evaluation. R.G. and M.C. provided methodological advice on the evaluation design and analysis of the study. D.B. and M.C. advised on clinical practice and interpretation of results. All authors read and approved the final manuscript.
Conflict of interest: None declared.
Correspondence: Rebecca Guy, PhD, Kirby Institute, The University of New South Wales, 45 Beach St, Coogee, NSW 2034, Australia. E-mail: firstname.lastname@example.org.
Received for publication September 20, 2012, and accepted November 28, 2012.
Gay men living with HIV are disproportionately affected by syphilis. In Australia, for example, rates of syphilis infection among gay men living with HIV are 5 to 10 times higher than among gay men who are HIV negative,1 with a similar epidemiology in Europe and North America.2 In most developed countries, annual case reports of syphilis diagnoses among gay men have risen steadily over the past decade.2–4
In response to this, sexual health testing guidelines in Australia recommend quarterly syphilis testing in HIV-positive men as part of HIV management checks, a promoted strategy since 2005/2006.5 In late 2006, a general practice in Sydney with a large number of gay male patients introduced an opt-out syphilis testing strategy as a standard part of regular HIV management checks. The clinic altered their electronic patient management system to include syphilis testing as a part of the battery of tests automatically requested for patients with HIV. Around the same time, the clinic shifted from 3 to 4 monthly viral load testing to 4 to 6 monthly for people with a stable HIV condition, a change formally recommended in guidelines around HIV monitoring from 2008 and maintained in the most recent update from 2012.6 Because viral load testing is a primary aspect of standard HIV management checkups, changes to these recommendations could affect the annual number of such checkups.
To assess the impact of these new clinic policies on syphilis testing, we collected de-identified retrospective syphilis and HIV viral load testing data from the clinic’s pathology providers for the period of 2005 through to 2010. The research received approval from the St Vincent’s Hospital Human Research Ethics Committee.
Using HIV viral load test requests as an indicator of HIV status, we developed 3 indicators for the male patients attending the clinic during this 6-year period: (1) syphilis testing frequency in HIV-positive men, (2) HIV viral load test frequency, and (3) the proportion of HIV viral load tests that had a syphilis test on the same day. Because the intervention was introduced in 2006, we compared these indicators between 2005 and 2007 and then over the next 3 years to assess sustainability using Pearson correlation, χ2, and rank sum tests.
In total, 1545 men had at least 1 viral load test between 2005 and 2010, and in each 12-month period, the number of men having at least 1 viral load test ranged from 592 to 877. The mean (SD) age in 2005 was 42.20 (9.54) years, which rose to 46.38 (9.47) years in 2010 (P < 0.001).
The mean number of syphilis tests per man rose from 1.14 in 2005 to 2.32 in 2007 (P < 0.001) (Fig. 1). In the following years, the mean number of tests remained consistent through 2008 (2.30), 2009 (2.30), and 2010 (2.45) (see Table 1 for a breakdown of syphilis testing annually). The proportion of participants who met the testing target of 3 or more tests in a year rose significantly from 10% in 2005 to 41% in 2007 (P < 0.001) and remained unchanged until the end of 2010 (P = 0.61). The proportion of men who had no syphilis tests in a 12-month period fell significantly from 27% in 2005 to 3% in 2007 (P < 0.001). This drop was sustained through 2008 (6%), 2009 (4%), and 2010 (3%) (P = 0.30).
The average number of viral load tests conducted per patient annually also rose (see Fig. 1), from 1.94 in 2005 to 2.32 in 2007 (P < 0.001), and remained consistent through 2008 (2.29), 2009 (2.29), and 2010 (2.33). In 2005, 28% of men had 3 or more HIV viral load tests, which rose to 41% in 2007 (P < 0.001) and was sustained thereafter.
In 2005, half of the viral load tests had a syphilis test on the same day, which then increased significantly to 88% in 2007 (P < 0.001) and remained at similarly high levels through 2008 (86%), 2009 (88%), and 2010 (90%). Overall, of the men having 3 or more HIV viral load tests, 72% also had 3 or more syphilis tests conducted. Of the men having 2 viral load tests, only 15% also had 3 or more syphilis tests conducted, and of the men having 1 viral load test in the year, only 5.7% also had 3 or more syphilis tests conducted. Table 1 shows the comparison between these 2 tests broken down by year.
The findings reported here demonstrate a marked and sustained increase in syphilis testing among gay men with HIV infection, which we attribute to the clinic’s opt-out strategy involving inclusion of syphilis screening as part of standard HIV management. Most men were tested for syphilis on the same day as they received an HIV viral load test, and most men received the same number of syphilis tests annually as they did viral loads. Men who had more viral load tests annually also tended to have more syphilis tests. The change observed in viral load testing rates between 2005 and 2007 is likely the result of an additional modification to the clinic’s patient management system, which, in late 2005, saw the creation of a standard battery of tests to be conducted during an HIV management checkup.
The success of this strategy, which is further buoyed by its simplicity and low cost, echoes findings from Melbourne and the UK where clinical management strategies increased the number of asymptomatic syphilis infections detected.7,8 However, although demonstrating success, this strategy was unable to increase syphilis testing to the recommended quarterly levels. Our analysis showed that syphilis testing was highly correlated with HIV viral load testing, but because 60% of men were having less than 3 HIV viral loads tests per year, quarterly syphilis testing for most men did not occur. It is possible that some men opted out of syphilis testing because they were sexually inactive or in a monogamous relationship. Although the clinic did not routinely collect sexual histories from patients, behavioral surveys show that between 14% and 16% of HIV-positive men report having a regular partner only.9
These findings could highlight the need for additional strategies working in tandem with the one described here to meet syphilis testing targets. In the Netherlands, for example, providing men with the opportunity to download syphilis testing referral letters and the distribution of results online saw an increase in syphilis testing rates among gay men.10 In keeping with the evolution of broader HIV management guidelines, these findings may also point to a need for revaluation of the testing guidelines, which currently recommend “3 monthly syphilis testing as a part of routine HIV monitoring.”5 Although quarterly syphilis testing remains an important goal, it seems clear that this target is beyond the reach of testing as a part of routine HIV monitoring.
Although the data collected for this analysis do not allow reporting on the impact of this intervention on syphilis detection rates, the implementation of a similar strategy in Melbourne found an increase in asymptomatic syphilis detections from 21% to 85%.7 The nature of risk assessment–based testing relies on regular accounting of sexual practices, which are not always done as part of HIV management checks. Thus, it would be expected that a shift from a risk assessment to opt-out based testing model would see, as it did in Melbourne, a rise in detection among gay men with HIV.
This is the first research, to our knowledge, that evaluates this type of intervention within a primary care setting. Given the increasing shift in Australia and overseas toward the management of HIV as part of primary care, this strategy represents an important tool toward increasing syphilis screening. Our study was strengthened by the long-term period of data collection, which allowed for assessment of sustainability and trends over time. A potential limitation was that some men might have sought HIV viral load or syphilis testing at other clinics, which would underestimate testing frequency but not the same-day testing outcomes. The findings reported here, however, are consistent with self-reported syphilis testing frequency in men with HIV infection.11 Finally, although this analysis was focused on assessing the sustainability of this type of intervention, detection rates were not collected, which is a limitation of this research.
In conclusion, the evaluation demonstrates the potential for syphilis testing to be significantly increased through its inclusion with standard HIV management procedures in primary care. Any clinic that manages patients with HIV and a high incidence of syphilis could benefit from the application of this electronic opt-out system or similar manual strategies to increase syphilis testing frequency.
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