This NC deficit may present with a wide spectrum of clinical symptoms, but typically includes patterns involving ineffective learning and problems with executive function, rather than pure difficulties in formulating new memory (the cortical defect
typical of Alzheimer’s disease ). Given the changing picture of this disease, a revised nomenclature system has been proposed classifying subjects with abnormal neuropsychological testing results in to three categories based on patient’s symptoms, measured via the activities of daily living scale . Subjects with abnormal neuropsychiatric testing results, who are otherwise asymptomatic, are classified as having Mitomycin C HIV-associated asymptomatic NC impairment; those who are mildly symptomatic are classified as having HIV-associated mild NC disorder; and those who are severely symptomatic are classified as having HIV-associated dementia. The clinical relevance of asymptomatic NC impairment, namely asymptomatic subjects with abnormal results on neuropsychological testing, remains unclear. Reports describing rates of NC impairment vary with some groups describing that up to 50% of HIV-positive subjects meet
the above diagnostic criteria . However, such reports should be interpreted with caution as asymptomatic subjects are often included and not all reports correct for effective ARV use. A Swiss cohort has reported 19% of aviraemic Progesterone HIV-positive subjects meet the classification for mild NC disorder or above see more . Risk factors for the development of NC disorders are poorly understood and are likely to be multifactorial, including both HIV disease factors  and concomitant diseases . Although
it is possible the choice of combination ART a subject receives may influence NC function, this is a controversial area without definitive evidence. The following recommendations apply to patients with symptomatic HIV-associated NC disorders. We recommend patients with symptomatic HIV-associated NC disorders start ART irrespective of CD4 lymphocyte count (1C). Proportion of patients with symptomatic HIV-associated NC disorders on ART. Current evidence suggests NC function improves after commencing ART for the first time  in both cognitively symptomatic  and asymptomatic  subjects. However, these studies have been undertaken in individuals with other indications to commence ART, in general with CD4 lymphocyte counts in the designated range where treatment is recommended. For subjects with higher CD4 lymphocyte counts, the ongoing START study will prospectively assess NC function in HIV-positive subjects commencing ART at an earlier stage of HIV disease. Therefore, ART is recommended in NC symptomatic subjects whose CD4 lymphocyte count itself is an indication to commence therapy.