title: Predictors of first line antiretroviral therapy failure and burden of second line antiretroviral therapy.
abstract: BACKGROUND
  As HIV steps into the third decade, there are more number of patients living on lifelong (antiretroviral therapy) ART and facing the threat of drug resistance with subsequent treatment failure. The aim of this study was to determine predictors of first-line ART failure with the objectives to estimate the burden of 2nd line ART.
  
  
  METHODS
  A retrospective 5-year cohort of HIV patients who were initiated on first line ART in 2008-09 was studied. Patients were followed from the time of ART initiation. Kaplan-Meier methods and Cox proportional hazards regression models were used to estimate probabilities and predictors of first line ART failure.
  
  
  RESULTS
  Of the total of 195 patients initiated on first line ART, 15 patients were switched to second line ART yielding 7.69% failure rate. During the 7178 person-years of follow-up, the incidence of first line ART failure was 2.09 per 1000 person-years. The Kaplan-Meier survival analysis gave a mean survival time of 55.6 months. BMI, CD4 count at ART initiation and presence of opportunistic infections were significant predictors of first line ART failure. The burden of second line ART patients by the end of 5 years of first line ART is expected to be 151 patients.
  
  
  CONCLUSIONS
  Though the first line ART failure is quite low in this study, we still need to be vigilant for lower BMI, low baseline CD4 count and occurrence of opportunistic infections to efficiently manage failures on first line ART.
authors.affiliation: Lecturer in Statistics, Dept of Community Medicine, Armed Forces Medical College, Pune 411040, India.
authors.forename: Seema
authors.initials: S
authors.lastname: Patrikar
authors.affiliation: Senior Advisor (Medicine & Clinical Immunology), Command Hospital (Air Force) Bengaluru, India.
authors.forename: Subramanian
authors.initials: S
authors.lastname: Shankar
authors.affiliation: Dy DGAFMS (Pension), O/o DGAFMS, Ministry of Defence, 'M' Block, New Delhi, India.
authors.forename: Atul
authors.initials: A
authors.lastname: Kotwal
authors.affiliation: Scientist 'F', Dept of Community Medicine, Armed Forces Medical College, Pune 411040, India.
authors.forename: D R
authors.initials: DR
authors.lastname: Basannar
authors.affiliation: Director Medical Services (Health), O/o DGAFMS, Ministry of Defence, New Delhi, India.
authors.forename: Vijay
authors.initials: V
authors.lastname: Bhatti
authors.affiliation: Consultant (Dermatology), Base Hospital, Lucknow, UP, India.
authors.forename: Rajesh
authors.initials: R
authors.lastname: Verma
authors.affiliation: Professor & Head, Dept of Community Medicine, Armed Forces Medical College, Pune 411040, India.
authors.forename: Sandip
authors.initials: S
authors.lastname: Mukherji
keywords: Antiretroviral therapy; First line ART failure; Human immunodeficiency virus; Survival