男男間性行為愛滋病毒感染者之梅毒感染相關因素

Abstract

目的 我們並不清楚台灣本土愛滋病毒感染者，特別是男男間性行為者（men who have sex with men，以下簡稱MSM），在高效能抗病毒藥物 ( highly active antiretroviral therapy，以下簡稱HAART ) 廣泛運用於愛滋病毒感染治療的時代，在性行為模式上是否有改變、是否正在從事危險性行為，使自己暴露在性病感染的風險中。因此，本研究希望能夠調查MSM之愛滋病毒感染者梅毒感染相關因子，以及娛樂性藥物與助性劑的使用和危險性行為的關聯性。

方法 本研究於2011年3月至2011年5月期間，以自填式問卷的方式，邀請規則在門診就醫之MSM愛滋病毒感染者參與本研究調查。所設計的結構式問卷，內容包含基本人口學資料、感染愛滋病毒後服藥與健康狀況及有無梅毒感染、性伴侶及性行為模式和娛樂性藥物使用概況。 結果 在這段研究期間，一共有200位個案自願參與本研究及提供有效問卷填答。在邏輯斯迴歸分析中，調整年齡、教育程度、職業、有無使用HAART、CD4數及病毒量之作用後，與梅毒感染相關的變項包括：固定性伴侶是愛滋病毒感染者、有不固定性伴侶者、全程及正確使用保險套頻率低者、肛交及口交戴套頻率低者、不戴套體外射精頻率高者、與愛滋病毒感染者發生性行為不戴套頻率低者，以及過去有娛樂性藥物及助性劑使用經驗者。針對有使用HAART的個案當中，進行複邏輯斯迴歸分析，最後結果為CD4數（odds ratio [OR], 1.0; 90% confidence interval [CI], 1.00-1.00; p＝0.018）、主要性伴侶「是」及「有的是有的不是」愛滋病毒感染者（OR, 5.42; 90% CI, 2.17-13.52; p＝0.002）、有不固定性伴侶（OR, 2.41; 90% CI, 1.30-4.47; p＝0.019）等為感染梅毒的相關因子。本研究未能確立娛樂性藥物與助性劑使用和梅毒感染之間的相關性，僅能呈現娛樂性藥物或助性劑的使用，的確與保險套使用頻率低之危險性行為和教育程度有關。 結論 本研究顯示，與性伴侶關係固定與否以及性伴侶的愛滋病毒感染身份，是MSM愛滋病毒感染者感染梅毒的重要相關因素。娛樂性藥物的使用和危險性行為之間的相關性，甚至兩者之間可能的協同作用，更是愛滋病防疫的一大挑戰，也顯現相關行為介入的措施有其必要性與急迫性。未來針對這群易感族群、性行為活躍之MSM愛滋病毒感染者，除了被動篩檢有無性病感染之外，應積極加強行為介入衛教宣導等次級預防工作。

Background & Purpose: Little is known about factors contributing to syphilis among HIV-infected patients in Taiwan, especially among men who have sex with men (MSM) , in the era of highly active antiretroviral therapy (HAART). Methods: From March to May 2011, HIV-infected MSM patients who regularly attended an HIV/AIDS outpatient clinic of a medical center were invited to participate in the study. Quantitative data were collected through a self-administered survey. The structured questionnaire for this study included questions regarding socio-demographic characteristics, HIV infection history, health status, sexual partners and patterns of sexual behavior, and use of recreational drugs. Results: During the study period, a total of 200 HIV-infected MSM were voluntarily enrolled and provided valid responses to the questionnaire. In the first stage analysis where association between each sexual or drug related factor and syphilis after diagnosis of HIV infection was examined while adjusting the effect of age, education, occupation, receiving HAART or not, CD4 counts, and plasma HIV RNA load (log10). We demonstrated the following factors that were associated with syphilis: having main sexual partner(s) who were also sero-positive, having casual sexual partner(s), condom use while having anal and oral sex, practice of withdrawal before ejaculation, having sex with sero-positive partner(s) without condom, and use of recreational drugs. Further stepwise multiple logistic regression analysis focusing on patients who were on HAART indicated that CD4 counts (OR, 1.0; 90% CI, 1.00-1.00; p＝0.018), having had sero-positive main partners before or some of the main sexual partners being HIV-positive (OR, 5.42; 90% CI, 2.17-13.52; p＝0.002), and having had casual sexual partner(s) (OR, 2.41; 90% CI, 1.30-4.47; p＝0.019) were statistically significant contributors for syphilis infection experience. This study failed to present a significant relationship between recreational drug use and syphilis. However, it did display an association between recreational drug use and education and risky sexual behaviors in the past 6 months. Conclusion: Findings of this study demonstrate the critical role the identity of sexual partners (sero-status) and the nature of relationship with sexual partners (steadiness or casualness) play in relation to syphilis. Moreover, association between risky sexual behaviors and recreational drug use and possible synergetic effect of both explicate the emerging challenge to HIV/AIDS control. It suggests the urgency to implement interventions targeting HIV-infected persons in general and HIV-infected MSM in particular.