Association between TB delay and TB treatment outcomes in HIV-TB co-infected patients: a study based on the multilevel propensity score method.

BACKGROUND: HIV-tuberculosis (HIV-TB) co-infection is a significant public health concern worldwide. TB delay, consisting of patient delay, diagnostic delay, treatment delay, increases the risk of adverse anti-TB treatment (ATT) outcomes. Except for individual level variables, differences in regional levels have been shown to impact the ATT outcomes. However, few studies appropriately considered possible individual and regional level confounding variables. In this study, we aimed to assess the association of TB delay on treatment outcomes in HIV-TB co-infected patients in Liangshan Yi Autonomous Prefecture (Liangshan Prefecture) of China, using a causal inference framework while taking into account individual and regional level factors. METHODS: We conducted a study to analyze data from 2068 patients with HIV-TB co-infection in Liangshan Prefecture from 2019 to 2022. To address potential confounding bias, we used a causal directed acyclic graph (DAG) to select appropriate confounding variables. Further, we controlled for these confounders through multilevel propensity score and inverse probability weighting (IPW). RESULTS: The successful rate of ATT for patients with HIV-TB co-infection in Liangshan Prefecture was 91.2%. Total delay (OR = 1.411, 95% CI: 1.015, 1.962), diagnostic delay (OR = 1.778, 95% CI: 1.261, 2.508), treatment delay (OR = 1.749, 95% CI: 1.146, 2.668) and health system delay (OR = 1.480 95% CI: (1.035, 2.118) were identified as risk factors for successful ATT outcome. Sensitivity analysis demonstrated the robustness of these findings. CONCLUSIONS: HIV-TB co-infection prevention and control policy in Liangshan Prefecture should prioritize early treatment for diagnosed HIV-TB co-infected patients. It is urgent to improve the health system in Liangshan Prefecture to reduce delays in diagnosis and treatment.

Perceptions of social norms played an important role in the occurrence of casual sex among Yi minority residents in China: a population-based study.

BACKGROUND: Liangshan is one of the areas severely affected by both HIV and poverty in China. We investigated associations between perceptions of social norms related to casual sex and the occurrence of casual sex in lifetime among Yi minority people. Participants were Yi minority people aged 15-49 years old living in Liangshan. Of the participants, 11.8% were confirmed to be HIV-positive. About half of the participants (46.6%) had engaged in casual sex in their lifetime. All six perceptions of social norms were significantly associated with the presence of casual sex in lifetime. They were acceptable of belife: (1) casual sex in general (OR: 15.03), (2) not to use condom during casual sex (OR: 1.58), (3) a Yi woman to have more than one sex partner(OR: 4.54), (4) a Yi man to have more than one sex partner(OR: 4.51), (5) premarital sex with casual sex partner (OR: 4.29), and (6) extra-marital sex with casual sex partner (OR: 3.23). Casual sex may play an important role in facilitating HIV transmission among Yi minority people. Future interventions should consider making use of the Yi clan system to change perceptions of social norms related to casual sex.

Factors related to HIV infection among unmarried youth in rural areas of Southwest China.

We evaluated HIV prevalence among unmarried youth in rural areas of Liangshan Prefecture in southwest China over the period of 2011-2015, and the interactions between behaviors associated with HIV risk. We used HIV sentinel surveillance (HSS) data for our analysis. We used questionnaires to investigate information among unmarried youth aged 15 to 25 years and performed HIV testing. Multivariate logistic regression and path analysis were applied to explore associations between behavioral factors related with HIV infection. A total of 9536 unmarried youth were enrolled in this study, of whom 2.75% (262/9536) tested positive for HIV infection. Multivariate logistic regression showed that male gender, Yi ethnicity, illiteracy, out-migrating for work, needle sharing, and engaging in high-risk sexual behaviors were risk factors. Path analysis revealed that needle sharing had the greatest effect on HIV infection (0.267), followed by drug use (0.171), out-migrating for work (0.079), and high-risk sexual behavior (0.064). The epidemic of HIV infection among unmarried youth in rural areas of Liangshan Prefecture is severe, and prevention efforts should focus on high-risk groups such as youth who are male, Yi, illiterate, and out-migrating for work, and those who engage in high-risk sexual behaviors and needle sharing.

[Analysis on migration of HIV/AIDS cases and related factors in Liangshan Yi Autonomous Prefecture in Sichuan province, 2020].

Objective: To analyze the migration of the HIV/AIDS cases and related factors in Liangshan Yi autonomous prefecture (Liangshan). Methods: According to HIV/AIDS Comprehensive Response Information Management System of China Information System for Disease Control and Prevention, a total of 28 772 HIV/AIDS cases who had follow-up records in Liangshan in 2020 were included in the survey. The migration of the HIV/AIDS cases was described and the related factors were analyzed using multiple logistic regression models, and the migration destinations of the HIV/AIDS cases were mapped. Results: Among the 28 772 HIV/AIDS cases, 20.89% (6 010/28 772) had migration in 2020. Multivariate logistic regression analysis showed that among the HIV/AIDS cases, the migration related factors included being aged 15-24 years (compared with being aged 0-14 years, OR=2.74, 95%CI:2.04-3.69) and ethnic group (compared with Han ethnic group, OR=2.44, 95%CI:2.19-2.72), having education level of junior high school (compared with having education level of primary school or below, OR=1.25, 95%CI:1.14-1.38), being unmarried (compared with being married, OR=1.29, 95%CI:1.20-1.39), being engaged in business services (compared with being engaged in farming, OR=1.96, 95%CI:1.31-2.92), receiving antiviral treatment <1 year (compared with receiving antiviral treatment >3 years, OR=1.42, 95%CI:1.26-1.61), having recent CD4+T lymphocytes (CD4) counts >500 cells/µl (compared with having recent CD4 counts <200 cells/µl, OR=1.15, 95%CI:1.03-1.29). The geographical distribution maps showed that among all cities in Sichuan, Xichang (13.26%, 797/6 010) and Chengdu (10.12%,608/6 010) were the main migration destinations of the HIV/AIDS cases, and the provinces outside Sichuan where the HIV/AIDS cases would like to migrate to were mainly Guangdong (18.19%, 1 093/6 010) and Zhejiang provinces (7.67%, 461/6 010) in 2020. The HIV/AIDS cases who migrated where Liangshan, within Sichuan province, and to other provinces accounted for 27.67% (1 663/6 010), 15.34% (922/6 010) and 56.99% (3 425/6 010), respectively. Conclusions: More attention should be paid to the mobility characteristics and the classification management of HIV/AIDS cases according to their characteristics in Liangshan. Timely access to information on changes in the place of work and residence of HIV/AIDS cases should be warranted when they have migration. Good referrals and management for mobility of HIV/AIDS cases in different places should be made to reduce loss to follow-up and improving interventions.

A New Strategy to Quantitatively Identify Hot-Spot Areas in Growth of New HIV Infections for Targeted Interventions.

Background: Previous geographic studies of HIV infection have usually used prevalence data, which cannot indicate the hot-spot areas of current transmission. To develop quantitative analytic measures for accurately identifying hot-spot areas in growth of new HIV infection, we investigated the geographic distribution features of recent HIV infection and long-term HIV infection using data from a whole-population physical examination in four key counties in Liangshan prefecture, which are most severely affected by HIV in China. Methods: Through a whole-population physical examination during November 2017- June 2018 in the four key counties, a total of 5,555 HIV cases were diagnosed and 246 cases were classified as recently infected by laboratory HIV recency tests. The geospatial patterns of recent and long-term HIV infected cases were compared using ordinary least squares regression and Geodetector. Further, geospatial-heterogeneity was quantified and indicated using a residual map to visualize hot-spot areas where new infection is increasing. Results: The geographic location of HIV cases showed an uneven distribution along major roads and clustered at road intersections. The geographic mapping showed that several areas were clustered with more recently infected HIV cases than long-term infected cases. The quantitative analyses showed that the geospatial asymmetry between recent and long-term HIV infection was 0.30 and 0.31 in ordinary least squares regression and Geodetector analysis, respectively. The quantitative analyses found twenty-three townships showing an increase in the number of recent infections. Conclusions: Quantitative analysis of geospatial-heterogeneous areas by comparing between recent and long-term HIV infections allows accurate identification of hot-spot areas where new infections are expanding, which can be used as a potent methodological tool to guide targeted interventions and curb the spread of the epidemic.

The changing modes of human immunodeficiency virus transmission and spatial variations among women in a minority prefecture in southwest China: An exploratory study.

Liangshan Yi Autonomous Prefecture in Southwest China has a high human immunodeficiency virus (HIV) prevalence rate. This study examined the changing modes of HIV transmission among women with new HIV infections and explored the spatial heterogeneities in the factors associated with heterosexual transmission in this minority region.The data consisting of women with new HIV infections from 2011 to 2014 were collected from multiple sources. New infections were identified by BED capture enzyme immunoassay. The Bayesian hierarchical model was used to estimate the proportion of women with new HIV infections via heterosexual transmission across all townships in the Prefecture. A geographically weighted regression (GWR) model was utilized to investigate spatial variations in the sociodemographic characteristics associated with the changing modes of HIV transmission.An analytical sample of 927 women with new HIV infections was constructed and utilized to investigate the changing mode of HIV transmission. The rate of heterosexual transmission among women with new HIV infections in 2011 was below 20%. However, by 2014 this rate dramatically increased to nearly 80%. Among sociodemographic characteristics, GWR results revealed significant ethnic differences in heterosexual HIV transmission between Yi women and women in other ethnic groups, with Yi women demonstrating a lower risk of infection through heterosexual transmission. However, such ethnic differences were observed only in 30% of the townships in the Prefecture. Moreover, having a primary education decreased the odds of heterosexual transmission, which was observed in about 56% of the townships. Also, being involved in occupations other than agriculture or animal husbandry and being single or married decreased the odds of HIV infection through heterosexual contact among women, which did not significantly vary across the Prefecture.Heterosexual transmission was the predominant mode of HIV transmission among women in the Prefecture, and this transformation was clearly marked by a fast-growing trend and a spatial diffusion pattern. Spatial variations also existed in sociodemographic factors that were associated with the changing modes of HIV transmission.

Factors associated with HIV infection among Yi minority residents in Liangshan Prefecture, Sichuan Province: A path analysis.

We aimed to evaluate HIV prevalence among residents of Liangshan Prefecture through HIV sentinel surveillance (HSS) data over the period from 2010 to 2016, and investigate risk factors for HIV infection in this population and interactions among them.Two sites (Dechang and Ningnan counties) with majority-Han populations, and 1 site (Butuo) with a majority-Yi population were selected. We used questionnaires to investigate residents' demographic and behavioral characteristics from 2010 to 2016, and performed HIV testing. Multivariate logistic regression and path analysis were undertaken to investigate the interactions and mediating effects among significant risk factors for HIV infection.A total of 5403 community residents in the Yi area and 10,897 community residents in the Han areas were enrolled. HIV prevalence in the Yi area was consistently high, ranging from 9.46% (63/666, 2011) to 2.88% (23/798, 2012) over the period from 2010 to 2016. HIV prevalence in the Han areas ranged from 0.15% (2/1333, 2010) to 0.44% (7/1604, 2011) over the same period. Multivariate logistic regression showed that unprotected casual sexual behavior, male gender, illiteracy, drug use, and injection drug use were positively associated with HIV infection risk in the Yi area. Path analysis of the risk factors revealed that casual sexual behavior (0.051) and injection drug use (0.161) were directly associated with HIV infection. However, marital status (0.004), ethnicity (0.017), education level (-0.004), HIV/AIDS-related prevention knowledge (-0.012), and drug use (0.11) had an indirect influence on HIV infection through casual sexual behavior and injection drug use.The prevalence of HIV is high among residents of majority-Yi areas, and injection drug use and casual sexual behavior are risk factors for infection.