Comparison of scales to evaluate the progression of HIV-associated neurocognitive disorder

Abstract

AIM: First, to compare the characterization of neurocognitive deficits in milder stages of HIV-associated neurocognitive disorder (HAND) derived from existing dementia rating scales of the American Academy of Neurology (AAN) and Memorial Sloan Kettering (MSK) with the 2007 consensus ('Frascati') classification. Second, to identify potential sociodemographic and clinical predictors of HAND progression during 1-year follow-up. METHODS: 104 HIV-infected subjects in an existing cohort system were evaluated with a medical history, exam, neuropsychological test battery and functional assessments. The degree of HAND was rated using the AAN, MSK and Frascati scales. The degree of concordance among these scales was determined. In addition, 45 subjects were reassessed for changes in their neurocognitive status at 1-year follow-up. Associations between age, education, sex, depression ratings, substance abuse, race, hepatitis C serostatus, CD4 count and progression of HAND were examined. RESULTS: There was excellent concordance (gamma > 0.8) among the Frascati, MSK and AAN ratings. Subjects rated as having minor cognitive motor disorder on the AAN scale (n = 45) were evenly split between Frascati rating of asymptomatic neurocognitive impairment (n = 24) and mild neurocognitive disorder (n = 21). At 1-year follow-up of 45 subjects, 31% had worsened, 13% had improved and 56% were stable. Predictors of progression included age older than 50 years (odds ratio: 5.57; p = 0.013) and female gender (odds ratio: 3.13; p = 0.036). CONCLUSION: The Frascati HAND rating scale has excellent concordance with previous neurocognitive rating scales and can be used to better characterize milder stages of cognitive impairment. Older individuals and women appeared to be more likely to show neurocognitive progression.

Figure 1. Distribution of neurocognitive diagnoses according to Frascati, asymptomatic neurocognitive impairment and Memorial Sloan Kettering ratings

MSK ratings are defined as follows: MSK 0.5: equivocal/subclinical cognitive impairment; MSK 1: mild dementia; MSK 2: moderate dementia. AAN: American Academy of Neurology; ANI: Asymptomatic neurocognitive impairment; HAD: HIV-associated dementia; MCMD: Minor cognitive motor disorder; MND: Mild neurocognitive disorder; MSK: Memorial Sloan Kettering.