 |
|
|
| |
Over Half of HIV+ 60 and Older Have Cognitive Deficit in San Francisco Study
|
| |
| |
19th Conference on Retroviruses and Opportunistic Infections, March 5-8, 2012, Seattle
"In this sample of HIV over age 60, approximately 50% of subjects were
cognitively intact.
Among subjects with impairment, most had MND (mild impairment). This differs from a recent publication among younger patients, where most impaired subjects had ANI[asymptomatic] (2).
Only two subjects were diagnosed with HAD - one died before year 2 follow-up
and one has had progressive decline in a manner suggestive of concurrent AD (age
79 at enrollment).
Most subjects in this sample of HIV over 60 years of age have been infected for
more than two decades."
Mark Mascolini
More than half of 75 HIV-positive people 60 or older had some cognitive impairment, usually mild neurocognitive disorder, according to results of a case-control study by Victor Valcour and colleagues at the University of California, San Francisco (UCSF) [1]. The researchers pointed out that the overall rate of neurocognitive impairment in this group does not exceed rates reported earlier in younger HIV cohorts. But the rate of mild neurocognitive disorder in their study group differed from that in a recent, smaller case-control study in which asymptomatic neurocognitive impairment accounted for most neurocognitive disorders [2].
Cognitive impairment remains prevalent among HIV-positive people responding to antiretroviral therapy. Although impairment risk increases with age in people with and without HIV, most studies of HIV populations have involved middle-aged and younger groups, Valcour and colleagues observed. Because an estimated 3000 HIV-positive people in the San Francisco area are 60 or older, they planned this study of neurocognitive impairment in an older population.
The UCSF investigators identified 98 HIV-positive people 60 and older, 75 of whom completed all baseline evaluations at the time of this analysis. Twenty-eight HIV-negative controls came from a healthy aging cohort at the same center. The study did not include anyone with a major neurologic disorder or learning disability. The researchers rated study participants for cognitive impairment with the standard 2007 HIV criteria [3].
Among the 75 people with HIV, 35 (47%) had normal cognition, 17 (23%) had asymptomatic neurocognitive impairment, 21 (28%) had mild neurocognitive disorder, and 2 (3%) had HIV-associated dementia. Four of 28 HIV-negative controls were women, compared with 3 of 75 people with HIV. Median age (and range) did not differ significantly between the HIV-negative controls (65, 61 to 70), the HIV-positive group with normal cognition (64, 60 to 76), HIV-positive people with mild neurocognitive disorder (66, 60 to 69), or the 2 people with dementia (71, 60 to 82). Education level was similar across HIV groups, though a higher proportion of controls had more than 16 years of education (P = 0.034).
About 80% of the HIV group became infected during sex between men. HIV infection duration averaged 21 years in the normal cognition group, 20 in the asymptomatic neurocognitive impairment group, 24 in the mild neurocognitive disorder group, and 9 in the dementia group. Almost everyone with HIV was taking antiretroviral therapy, average CD4 counts stood above 500 in all four HIV groups, and a large majority had a viral load below 400 copies in plasma.
Of the 2 people with HIV-associated dementia, 1 died before 2 years of follow-up and the other, who was 79 years old at enrollment, had progressive decline.
Univariate analysis found no predictors of cognitive impairment--not even any suggestive trends--in a list of factors including HIV duration, current CD4 count, nadir CD4 count, viral load in plasma, antiretroviral central nervous system penetration effectiveness score, diabetes, hypertension, smoking, and hypercholesterolemia.
Valcour and colleagues cautioned that the equivalent neurocognitive disorder rate found in these older HIV-positive people and in younger HIV groups may reflect enrollment bias in their study (which excluded anyone with major neurologic disease) or survival bias (these 60-and-older people survived many peers). They noted that lack of association between cognition and typical HIV risk factors, such as nadir CD4 count, may also point to survival tendencies in their study group.
Considering all their findings, the investigators suggested "these early data raise concern that typical cognitive risk factors may be less applicable for the current oldest demographic" of people with HIV.
References
1. Victor Valcour V, Nicolas K, Busovaca E, et al. Survivorship and cognition in HIV over age 60. 19th Conference on Retroviruses and Opportunistic Infections. March 5-8, 2012. Seattle. Abstract 498. http://www.retroconference.org/2012b/PDFs/498.pdf.
2. Ances BM, Christensen JJ, Teshome M, et al. Cognitively unimpaired HIV-positive subjects do not have increased 11C-PiB: a case-control study. Neurology. 2010;75:111-115.
3. Antinori A, Arendt G, Becker JT, et al. Updated research nosology for HIV-associated neurocognitive disorders. Neurology. 2007;69:1789-1799.
---------------------------
Cognition in HIV Over 60 - Potential Impact of Survivorship
The UCSF HIV Over 60 Cohort
Victor Valcour MD1,2, Krista Nicolas BS1, Howard J. Rosen MD1, Edgar Busovaca BS1, Lauren A. Wendelken MS1, Katherine P. Rankin PhD1, John Neuhaus PhD3, Bruce Miller MD1
Memory and Aging Center, Department of Neurology, University of California at San Francisco, USA; (2) Division of Geriatric Medicine, Department of Medicine, University of California at San Francisco, USA; (3) Division of Biostatistics and Epidemiology, University of California, San Francisco, USA
|
| |
|
|
|
|
|
