Objective Since community viral load (CVL) measurements are associated with incidence

Objective Since community viral load (CVL) measurements are associated with incidence of new HIV-1 infections in a population we hypothesized that similarly measured community drug resistance (CDR) could predict prevalence of transmitted drug resistance (TDR). 103 in RT. Each of these associations was corroborated at least once using shorter measurement intervals. Conclusions Despite evaluation of a limited percentage of chronically infected patients in San Diego CDR correlated with TDR at important resistance positions and therefore may be a useful tool to predict the prevalence of TDR. gene can confer decreased susceptibility to antiretroviral therapy (ART)(1). Failure of ART to fully suppress viral replication (i.e. treatment failure) can select for viral populations that harbor these mutations in the presence of ongoing therapy. These mutations can also be found in viral populations among people who have by no means taken ART i.e. transmitted drug resistance (TDR)(2). The primary source of TDR is usually from patients on failing ART regimens with incomplete viral suppression in whom drug resistance mutations have been selected or from subjects with TDR. Since steps of HIV-1 viral weight at the community level (i.e. community viral weight) have recently been shown to be associated with the incidence of new HIV infections in general populations as well as specific high-risk groups(3 4 we questioned if comparable steps of community drug resistance (CDR) could be Tyrphostin AG-1478 related to the prevalence of overall TDR. Specifically we tested the hypothesis that CDR calculated from a limited group of patients receiving care at a local HIV medical center with sufficient viral loads and resistance data available could be associated with the prevalence of TDR in people recently infected with HIV in the same community over the same time period. Methods Study populations and screening This project was approved by the local committee for the protection of human subjects. Chronic contamination cohort: The UCSD Owen Medical center is usually a multidisciplinary medical center that provides comprehensive health care services to approximately 30% of the patients receiving care for HIV/AIDS in San Diego County California. The Tyrphostin AG-1478 total quantity of HIV-infected individuals living in San Diego in 2011 Tyrphostin AG-1478 the last year of the study was 7 221 (5). It is estimated that 85% of HIV-infected individuals in San Diego are aware of their diagnosis 54 are linked to care 32 receive regular care and 31% have suppressed viral weight (unpublished data from County of San Diego Health and Human Services HIV STD and Hepatitis Branch HIV/AIDS Epidemiology Unit). Of those Owen Clinic participants who entered care since 2005 the median and mean lengths of follow-up are 651 and 813 days respectively and the average attrition rate is usually 11.7% per year. Attrition was defined as patients not returning for any clinical visit within the periods of observation. Medical center data on attrition rates before 2005 were less total and likely not as reliable. Available data between 2001 and 2011 included patient age Rabbit polyclonal to LRCH4. sex race ethnicity HIV risk factor(s) CD4+ T-lymphocyte counts HIV-1 viral loads and results of resistance screening (either Genseq? HIV or PhenoSense GT; Monogram Biosciences Inc. South San Francisco California). Standard of care for San Diego County in the study period of observation was for viral loads and CD4 counts to be measured every three months and over 80% of patients followed longitudinally between 2001 and 2011 met this standard(6). Resistance screening was performed in patients on ART with a viral weight of ≥1 0 HIV RNA copies/mL throughout the study period and baseline resistance screening on treatment na?ve patients was applied in the medical center in 2006. Since these data were obtained in a clinical cohort it was not Tyrphostin AG-1478 always obvious if resistance screening occurred in the setting of treatment failure. All patients with an available resistance test result between 2001 and 2011 were included in CDR calculations for the main analysis. Given the longitudinal nature of this cohort some patients had more than one resistance test included in the analysis although only one resistance test per patient was included for a given calendar year. For patients with more than one resistance test for a given year the Tyrphostin AG-1478 last result was included. Approximately 14% of all patients who underwent viral weight testing during this time period experienced an available.