HIV and syphilis infections and associated factors among patients in treatment at a Specialist Alcohol, Tobacco, and Drugs Center in São Paulo’s “Cracolândia” virus

Introduction: This study describes the epidemiological scenario of human immunodeficiency (HIV) and syphilis at the biggest specialist drug addiction center in Brazil. The great challenge is to find strategies to reduce the impact of inequality and discrimination and develop policies to protect individuals living with – or at risk of – infections. Methods: During the period from January 1 to May 31, 2016, a cross-sectional study was conducted on which all patients (N = 806) seeking inpatient treatment were enrolled. A structured diagnostic interview and rapid tests were conducted initially, and diagnoses were confirmed by tests conducted at a venereal disease research laboratory (VDRL). Results: HIV and syphilis rates were 5.86% and 21.9%, respectively. Women were nearly 2.5 times more likely to have syphilis. HIV infection was associated with unprotected sex (odds ratio [OR]: 3.27, p = 0.003, 95% confidence interval [95%CI]: 1.51-7.11), and suicidal ideation (OR: 6.63, p = 0.001, 95%CI: 3.37-14.0). Although only 1.86% reported injecting drugs at any point during their lifetimes, this variable was associated with both HIV and syphilis. Elevated rates of HIV and syphilis were observed in the context of this severe social vulnerability scenario. Conclusion: The risk factors identified as associated with HIV and syphilis should be taken into consideration for implementation of specific prevention strategies including early diagnosis and treatment of sexually transmitted infections (STI) to tackle the rapid spread of STIs in this population.


Introduction
The burden of sexually transmitted infections (STIs) and crack cocaine use is higher in low and middleincome countries than in high-income ones and the great challenge is to find strategies to reduce the impact of inequality and discrimination and to develop policies to protect individuals living with or at risk of infections. [1][2][3][4] Approximately 47% of all human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/ AIDS) cases in Latin America 5 are in Brazil, which is also the country with the highest rate of crack cocaine use, affecting 0.8% of the total population. 6 Although no significant reductions in supply or demand for crack cocaine have occurred recently, HIV/AIDS prevention and treatment initiatives have reduced the incidence of new HIV/AIDS cases significantly all over the globe, 5 from 3.1 million in 2000 to 2.1 million in 2015. In Brazil, however, reports showed a 53.2% increase in HIV rates amongst those aged 15 to 19 and a 10.3% increase among those aged 20 to 24 between 2004 and 2013. 5,7 The increase in HIV rates was followed by a significant increase in syphilis infections. 7 In Brazil, a calamitous increase in acquired syphilis infections was observed between 2011 and 2016, despite government efforts at containment. In 2015, primary syphilis accounted for 31.6% of the total number of cases, while latent, secondary and tertiary syphilis accounted for 23.6%, 10.7% and 5.8%, respectively. 7,8 The scenario is of even greater concern when it comes to syphilis during pregnancy: in this population the detection rate increased from 3.7 to 11.2% over the same period. 8 This increase was followed by a rise in the incidence rate of congenital syphilis (from 2.4 to 6.5%), underscoring the severity of the epidemiological situation. 9 Based on previously established risk factors associated with STIs and HIV in substance use disorders (SUD), public health policies have been proposed and implemented in Brazil, usually focusing on prioritizing specific high-risk populations (i.e. sex workers, men who have sex with men, transgender people and drug users). [10][11][12] Annually, Brazil consumes a third of all cocaine destined for the South American market and is currently the largest crack consumer on the planet. 13 In 2012, the proportion of the country's population that consumed reached 0.8%, 6 while the most common route of transmission of STI and HIV is sexual. 14 The greatest open-air concentration of drug users is in São Paulo, in an area known nationally as "Cracolândia," where drugs are used and traded non-stop. 13 Although data on the prevalence of STIs among crack cocaine users in the Cracolândia setting is still limited, early studies have illustrated that the problems described above constitute a synergy between social vulnerability, low education and economic inequality. 15

Discussion
The staggering rates of HIV and syphilis detected amongst individuals seeking treatment for SUD in São Paulo (5.8% and 21.9%, respectively) underscore the urgent need to develop more effective prevention and treatment strategies. Our findings indicate that current prevention and treatment strategies are either insufficient or poorly targeted at the key populations. 7,15 In addition, most of the sample reported having had unprotected sex in the preceding month, 18  It is relevant to mention that suicidal ideation assessment was performed before HIV test results were disclosed, thereby reducing the possibility of an immediate impact. There is a large body of evidence to support the belief that suicidal ideation is not only associated with crack cocaine abuse, but also with the diagnosis of HIV infection. This relationship is even more apparent during the first few months following diagnosis. 19 There are recently-reported findings in the medical literature in which it was noted that suicidal ideation was significantly associated with diagnosis of HIV in the preceding three years (n = 304 patients). 22 This association emphasizes the importance of implementing suicide prevention measures at addiction services.

Limitations
The study was performed at a single center with a convenience sample. Consequently, the risk of selection bias has to be addressed. CRATOD is located in the heart of Cracolândia, thus, it is reasonable to assume that the population treated at CRATOD is not representative of the wider substance use disorder population. These patients are probably facing more severe addiction and in a more vulnerable situation. Only six patients refused to take the rapid test, and remain in the study, with the data counted as missing. According to the database used, one of these six patients had been tested at another service and a diagnosis of syphilis was found on the system and this individual was counted as positive for VDRL. This description is included as a study limitation.
It can therefore be assumed that generalizability is limited. Furthermore, there is a possibility of underreporting, since all of the information on drug intake and risk behaviors was based on self-reports.

Conclusions
Elevated rates of HIV and syphilis were ascertained in the context of an extremely severe social vulnerability scenario. The most significant risk factors identified as associated with STI, such as suicidal ideation, unprotected sex and drug injection, should be taken into consideration for implementation of specific prevention strategies based on early diagnosis and treatment of sexually transmitted infections, to tackle the rapid spread of STI in this population.