Establishment And Application Of HIV Risk Prediction Model Among Chinese MSM

Objective:Men who have sex with men(MSM)is an important challenge in HIV prevention and control in China.Despite various interventions,the number of HIV-positive MSM is still increasing year by year,and an innovative new intervention strategy is urgently needed.In recent years,the way that MSM has looked for sexual partners has shifted to social software on the Internet,which broadly exacerbate the spread of HIV in MSM.The traditional interventions based on MSM venues or voluntary counseling and testing centers are no longer suitable for the new needs of AIDS prevention and control.However,the Internet-based electronic intervention has become a powerful place and tool for HIV prevention and control in MSM.HIV self-risk perception is a comprehensive measure of attitudes and beliefs which is an important dimension of many theoretical models of health promotion.However,most current HIV risk assessment tools for MSM are developed by American cohorts.Due to the difference of social or cultural backgrounds and the distribution of risk factors,these tools often do not suitable for the Chinese MSM.Therefore,it is urgent needed for developing a HIV risk prediction model targeting Chinese MSM in our country and the behavior intervention strategy based on it.The purpose of our study is to establish a HIV infection risk prediction tool in Chinese MSM and to evaluate the efficacy and cost-effectiveness of the targeted behavioral interventions based on it,which could indicate the early warning,prevention and early intervention for Chinese MSM.MethodsWe retrospectively collected prospective cohort data of HIV-negative MSM from the Voluntary Counseling and Testing Clinic(VCT)of the First Affiliated Hospital of China Medical University from 2009 to 2016 to screen the predictors of HIV infection,construct the HIV risk prediction model and verify its accuracy.A 12-week online randomized controlled clinical trial was conducted to assess the effectiveness of a comprehensive intervention strategy based on HIV risk assessment.MSM willing to participate in clinical trials were recruited through MSM social software.MSM met the inclusion criteria and agreed that enrollment were randomized into the intervention or control group.Comprehensive intervention package was pushed through We Chat which including risk assessment based on HIV risk prediction models,free online condom and self-test papers,HIV voluntary counseling and testing site,and HIV / AIDS epidemic and prevention Knowledge,while the control group only push AIDS epidemic and prevention knowledge.Twelve weeks latter,the effectiveness and cost-effectiveness of online behavioral interventions were evaluated using online questionnaires.Results:In the first part of the study,a total of 999 MSM were included in the construction and validation of risk prediction models.Multivariate Cox regression analysis showed unprotected active anal intercourse with sexual partner in the past 3 months(a HR=0.22,95% CI: 0.09-0.55),unprotected passive anal sex in the past 3 months(a HR = 3.01,95% CI: 1.48-6.16),looking for sexual partners via internet/social software(vs.in baths and parks)(a HR=2.70,95%CI: 1.02-7.14),looking sexual partners in bar/club(vs.in baths and parks)(a HR=7.84,95%CI: 2.64-22.91),and rush poppers usage(a HR=2.40,95%CI: 1.10-5.27)were independent associated with HIV seroconversion in Chinease MSM cohort.C statistic of the internal validation of the model based on Bootstrap technology was 0.75,and 0.60 for the validation dataset.At the same time,this study also developed the nomogram and online risk assessment tool based on the risk prediction model constructed.In the second part of the study,192 eligible MSM were recruited through the MSM social platform.At the 12 th week follow-up,a total of 168 follow-up questionnaires were collected.The follow-up cohort retention rate was 87.5%(168/192).The results of the analysis showed that the number of homosexual partners in the intervention group was significantly lower than that in the control group(3.51±4.1 vs.6.01±11.4,P<0.045)in the past 3 months,and the rate of persistent condom usage was even higher with the occasional sexual partner than that in the control group(86.8% vs.70.1%,P = 0.012).The proportion of intending to detect HIV in the next 30 days in intervention group was slightly higher than that in the control group(89.9% vs.80.2%,P = 0.069).In the third part of the study,it was found that the percentage of condoms usage in the intervention was 16.7% higher thant in the control group,and the cost of per 1 percentage increase was 132 yuan;the average number of sexual partners in the intervention group may decline 2.5,and the cost of 1 reduction is 884 yuan.Based on the mathematical model,it is estimated that the cost of intervention for 10,000 MSM for one year is 798,960 yuan and the cost of one person intervention is 79.9 yuan.The input can prevent 48 MSM from HIV infection,which could save 7923216 yuan and 480 QALY.The cost of avoiding 1 case of HIV infection is 16,645 yuan,and the cost-utility ratio is less than 0.Conclusion:This study has developed a tool for predicting the risk of HIV infection in Chinese MSM.There is a good agreement between predicted efficacy and actual observed risk.Comprehensive intervention strategies based on the HIV infection risk prediction model can reduce the number of male sexual partners and increase the rate of condom usage with occasional partners.The intervention is cost effectiveness and could be considered for large-scale promotion and application.