Objectives: To study determinants of late HIV diagnosis in a low-HIV-prevalence (<0.1%) country where HIV spread among men who have sex with men (MSM) and heterosexuals in the 1980s, and among injecting drug users (IDUs) in the late 1990s.
Methods: Newly diagnosed HIV cases referred to the Helsinki University Central Hospital between 1985 and 2005 were reviewed to identify determinants of late HIV diagnosis, defined as diagnosis when the first CD4 count was <200 cells/microL, or when AIDS occurred within 3 months of HIV diagnosis. Determinants of late diagnosis were analysed using multivariate logistic regression.
Results: Among 934 HIV cases, 211 (23%) were diagnosed late. In the first 4-year interval of each sub-epidemic (1985-1989 for MSM and heterosexuals, 1998-2001 for IDUs), rates of late HIV diagnosis were 13%, 18% and 6%, respectively, but increased thereafter to 29%, 27% and 37%. Late diagnosis was associated with non-Finnish ethnicity, older age, male gender, lack of earlier HIV testing, diagnosis at health care settings and later stage of the sub-epidemic.
Conclusions: The lower rate of late diagnosis in the first 4-year interval of each HIV sub-epidemic suggests that the early stages of the HIV epidemic in Finland were detected early. This factor may have contributed to the low prevalence of HIV infection in Finland. The stage and age of the epidemic should be taken into account when interpreting the data on late HIV diagnosis, especially in cross-country comparisons.