Late presentation of HIV infection among adults in New Zealand: 2005-2010

Early diagnosis of HIV infection is important for the individual and for disease control. A consensus was recently reached among European countries on definitions of timing of presentation for care: 'Late presentation' refers to entering care with a CD4 count <350 cells/μL or an AIDS-defining event, regardless of the CD4 count. Presentation with 'advanced HIV disease' is a subset having a CD4 count <200 cells/μL and also includes all who have an AIDS-defining event regardless of CD4 count. This study examines timing of presentation in New Zealand from 2005 to 2010.

Since 2005, information on the initial CD4 cell count has been requested on all people newly diagnosed with HIV infection through antibody testing in New Zealand. Excluded in this analysis were those previously diagnosed overseas or for an immigration medical.

A CD4 cell count was provided for 606 (80.3%) of the 755 newly diagnosed adults. Overall, 50.0% were 'late presenters' and 32.0% had 'advanced HIV disease'. Compared with men who have sex with men (MSM), people heterosexually infected were more likely to present late. 'Late presentation' and presentation with 'advanced HIV disease' were significantly more common among older MSM. Māori and Pacific MSM were more likely to present with 'advanced HIV disease'. Compared with European MSM, the age-adjusted relative risks for Māori and Pacific MSM were 2.1 [95% confidence interval (CI) 1.4-3.2] and 2.5 (95% CI 1.2-5.0), respectively.

The high proportion of people presenting late reflects inadequate levels of HIV testing. The lower proportion of late presentations among MSM compared with those heterosexually infected may be explained by a higher proportion of recent locally acquired infections together with different testing patterns.