title: Prevalence of transmitted HIV-1 drug resistance in HIV-1-infected patients in Italy: evolution over 12 years and predictors.
abstract: OBJECTIVE
  Transmitted HIV-1 drug resistance (TDR) can reduce the efficacy of first-line antiretroviral therapy.
  
  
  METHODS
  A retrospective analysis was performed to assess the prevalence and correlates of TDR in Italy over time. TDR was defined as the presence of at least one of the mutations present in the surveillance drug resistance mutation (SDRM) list.
  
  
  RESULTS
  Among 1690 antiretroviral therapy-naive patients, the most frequent HIV subtypes were B (78.8%), CRF02_AG (5.6%) and C (3.6%). Overall, TDR was 15%. TDR was 17.3% in subtype B and 7.0% in non-B carriers (P < 0.001). TDR showed a slight, although not significant, decline (from 16.3% in 1996-2001 to 13.4% in 2006-07, P = 0.15); TDR declined for nucleoside reverse transcriptase inhibitors (from 13.1% to 8.2%, P = 0.003) but remained stable for protease inhibitors (from 3.7% to 2.5%, P = 0.12) and non-nucleoside reverse transcriptase inhibitors (from 3.7% to 5.8%). TDR to any drug was stable in B subtype and showed a decline trend in non-B. In multivariable analysis, F1 subtype or any non-B subtype, compared with B subtype, and higher HIV RNA were independent predictors of reduced odds of TDR.
  
  
  CONCLUSIONS
  Prevalence of TDR to nucleoside reverse transcriptase inhibitors seems to have declined in Italy over time. Increased prevalence of non-B subtypes partially justifies this phenomenon.
authors.affiliation: Institute of Clinic of Infectious Diseases, Catholic University of Sacred Heart, Rome, Italy. laura.bracciale@poste.it
authors.forename: L
authors.initials: L
authors.lastname: Bracciale
authors.forename: M
authors.initials: M
authors.lastname: Colafigli
authors.forename: M
authors.initials: M
authors.lastname: Zazzi
authors.forename: P
authors.initials: P
authors.lastname: Corsi
authors.forename: P
authors.initials: P
authors.lastname: Meraviglia
authors.forename: V
authors.initials: V
authors.lastname: Micheli
authors.forename: R
authors.initials: R
authors.lastname: Maserati
authors.forename: N
authors.initials: N
authors.lastname: Gianotti
authors.forename: G
authors.initials: G
authors.lastname: Penco
authors.forename: M
authors.initials: M
authors.lastname: Setti
authors.forename: S
authors.initials: S
authors.lastname: Di Giambenedetto
authors.forename: L
authors.initials: L
authors.lastname: Butini
authors.forename: A
authors.initials: A
authors.lastname: Vivarelli
authors.forename: M
authors.initials: M
authors.lastname: Trezzi
authors.forename: A
authors.initials: A
authors.lastname: De Luca
mesh_terms: D000328:Adult; D019943:Amino Acid Substitution; D019380:Anti-HIV Agents / Q000494:pharmacology; D024882:Drug Resistance, Viral; D005260:Female; D005838:Genotype; D015658:HIV Infections / Q000453:epidemiology* / Q000635:transmission / Q000821:virology*; D017320:HIV Protease Inhibitors / Q000494:pharmacology; D015497:HIV-1 / Q000145:classification* / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D020125:Mutation, Missense; D015995:Prevalence; D012367:RNA, Viral / Q000235:genetics; D012189:Retrospective Studies; D018894:Reverse Transcriptase Inhibitors / Q000494:pharmacology
chemical_list: D019380:Anti-HIV Agents; D017320:HIV Protease Inhibitors; D012367:RNA, Viral; D018894:Reverse Transcriptase Inhibitors