title: [Sildenafil use and relevant risk factors among middle-aged or elderly male clients of female commercial sex workers in the central areas of Guangxi, China].
abstract: OBJECTIVE
  To understand the illegal sidenafil use among middle-aged and elderly male clients of female sex workers (FSWs) in central region of Guangxi as well as on related risk factors. Initial evaluation regarding the effect of illegal sidenafil use on HIV infection among the middle-aged and elderly men was also conducted.
  
  
  METHODS
  A survey was conducted among the over 50-year-olds male clients of low-grade prostitutions in central areas of Guangxi. Information on demographics, related behavior, and illegal sidenafil use was collected. 5 ml blood sample were taken to test antibodies of HIV and syphilis. PASW Statistics 18.0 was used for data analysis.
  
  
  RESULTS
  2 056 questionnaires were completed. 23.1% of the participants said they had ever used illegal sidenafil. The risk of sildenafil use was low among the male clients who were not over 60 years old (OR = 0.586, 95% CI:0.459-0.749). The risks of sildenafil use among the male clients with frequencies(in the past 30 days) of having commercial sex behavior were:only once (OR = 0.184, 95%CI:0.090- 0.378), twice (OR = 0.187, 95%CI:0.089-0.378) or three times (OR = 0.181, 95%CI: 0.085-0.384) lower than those with more than five times. Being single (OR = 0.608, 95% CI: 0.396-0.933), married/cohabiting (OR = 0.533, 95% CI:0.391-0.727), having unstable partners (OR = 0.558, 95%CI:0.393-0.792) seemed to be protective on those who used sildenafil, among the study population. Factors as 'never use the condom (OR = 1.642, 95%CI:1.125-2.397) or 'seldom use as condom (OR = 1.840, 95%CI:1.278-2.648) when having commercial sex, were under high risk among the sildenafil users. Forty-seven subjects were HIV positive, with the prevalence as 2.29% in this study population. Male clients of the FSWs who used sidenafil were under 60 years of age and with higher risk of HIV infection.
  
  
  CONCLUSIONS
  people who were ≥60 years old, divorced/widowed/ separated, with frequencies (in the past 30 days) of having commercial sex more than 5 times, never or occasionally using a condom when having commercial sex etc., appeared at high risk. Middle-aged and elderly male clients who used sildenafil or sildenafil-like drugs were under high risk of contracting HIV infection.
authors.affiliation: Guangxi Zhuang Autonomous Region Center for Disease Control and Prevention, Nanning 530028, China.
authors.forename: Huaxiang
authors.initials: H
authors.lastname: Lu
authors.affiliation: Guangxi Zhuang Autonomous Region Center for Disease Control and Prevention, Nanning 530028, China. Email: tangzhzh@163.tom.
authors.forename: Zhenzhu
authors.initials: Z
authors.lastname: Tang
authors.affiliation: Guangxi Zhuang Autonomous Region Center for Disease Control and Prevention, Nanning 530028, China.
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Shen
authors.affiliation: Guangxi Zhuang Autonomous Region Center for Disease Control and Prevention, Nanning 530028, China.
authors.forename: Xinghua
authors.initials: X
authors.lastname: Wu
authors.affiliation: Guangxi Zhuang Autonomous Region Center for Disease Control and Prevention, Nanning 530028, China.
authors.forename: Qiuying
authors.initials: Q
authors.lastname: Zhu
authors.affiliation: Guangxi Zhuang Autonomous Region Center for Disease Control and Prevention, Nanning 530028, China.
authors.forename: Huanhuan
authors.initials: H
authors.lastname: Chen
authors.affiliation: Guangxi Zhuang Autonomous Region Center for Disease Control and Prevention, Nanning 530028, China.
authors.forename: Liuhong
authors.initials: L
authors.lastname: Luo
authors.affiliation: Guangxi Zhuang Autonomous Region Center for Disease Control and Prevention, Nanning 530028, China.
authors.forename: Li
authors.initials: L
authors.lastname: Chen
mesh_terms: D017677:Age Distribution; D000368:Aged; D002681:China / Q000453:epidemiology; D017280:Condoms / Q000706:statistics & numerical data; D005260:Female; D015658:HIV Infections / Q000453:epidemiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010879:Piperazines / Q000008:administration & dosage*; D063487:Prescription Drug Misuse / Q000331:legislation & jurisprudence*; D015995:Prevalence; D011687:Purines / Q000008:administration & dosage; D012307:Risk Factors; D011477:Sex Work; D060386:Sex Workers; D012747:Sexual Partners; D000068677:Sildenafil Citrate; D013449:Sulfonamides / Q000008:administration & dosage*; D013587:Syphilis / Q000453:epidemiology
chemical_list: D010879:Piperazines; D011687:Purines; D013449:Sulfonamides; D000068677:Sildenafil Citrate