title: HIV transmission and high rates of late diagnoses among adults aged 50 years and over.
abstract: OBJECTIVE
  Describe the epidemiology and impact of late diagnosis among older adults living with HIV and estimate age at infection.
  
  
  METHODS
  Comparative national analyses between individuals diagnosed when aged 50 years and over with individuals diagnosed prior to 50 years. Age at infection was estimated using CD4 cell count at diagnosis.
  
  
  RESULTS
  A total of 8255 older adults accessed HIV care in England, Wales and Northern Ireland in 2007, a 3.5-fold increase compared to 2000; with one in 10 individuals newly diagnosed in 2007. When compared with younger adults at diagnosis, older adults were significantly more likely to be men (74 vs. 58%; P < 0.001), infected through sex between men (40 vs. 34%; P < 0.001) and of white ethnicity (60 vs. 38%; P < 0.001). Older heterosexual adults were more likely to be infected within the UK (16 vs. 12%; P < 0.001), with evidence of travel abroad among white heterosexual men. Almost half (48%) of older adults were late presenters vs. a third (33%) of younger adults. Older late presenters were 14 times more likely to die within a year of diagnosis compared with older adults who were not diagnosed late (14 vs. 1%; P < 0.001) and had 2.4 times the risk of dying than younger late presenters. We estimate that nearly half (48%) of older adults diagnosed between 2000 and 2007 acquired their infection at age 50 and over.
  
  
  CONCLUSIONS
  Our study provides evidence of HIV transmission, high rates of late presentation and an increased risk of short-term mortality among older adults. These findings highlight the need for increased targeted prevention efforts and strategies to increase HIV testing among older adults at risk of HIV.
authors.affiliation: HIV and STI Department, Health Protection Agency Centre for Infections, Colindale, London, UK. ruth.smith@hpa.org.uk
authors.forename: Ruth D
authors.initials: RD
authors.lastname: Smith
authors.forename: Valerie C
authors.initials: VC
authors.lastname: Delpech
authors.forename: Alison E
authors.initials: AE
authors.lastname: Brown
authors.forename: Brian D
authors.initials: BD
authors.lastname: Rice
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000465:Algorithms; D018791:CD4 Lymphocyte Count / Q000379:methods; D057210:Delayed Diagnosis / Q000706:statistics & numerical data*; D004739:England / Q000453:epidemiology; D005260:Female; D015658:HIV Infections / Q000175:diagnosis* / Q000401:mortality / Q000635:transmission; D006801:Humans; D008297:Male; D008875:Middle Aged; D009660:Northern Ireland / Q000453:epidemiology; D011159:Population Surveillance; D012307:Risk Factors; D018571:Sentinel Surveillance; D017678:Sex Distribution; D012725:Sexual Behavior / Q000706:statistics & numerical data*; D013997:Time Factors; D014852:Wales / Q000453:epidemiology; D055815:Young Adult