Despite immune recovery in individuals on combination antiretroviral therapy (CART), the frequency of HIV-associated neurocognitive disorders (HANDs) remains high. Immune recovery is typically ...achieved after initiation of ART from the nadir, or the lowest historical CD4. The present study evaluated the probability of neuropsychological impairment (NPI) and HAND as a function of CD4 nadir in an HIV-positive cohort.
One thousand five hundred and twenty-five HIV-positive participants enrolled in CNS HIV Antiretroviral Therapy Effects Research, a multisite, observational study that completed comprehensive neurobehavioral and neuromedical evaluations, including a neurocognitive test battery covering seven cognitive domains. Among impaired individuals, HAND was diagnosed if NPI could not be attributed to comorbidities. CD4 nadir was obtained by self-report or observation. Potential modifiers of the relationship between CD4 nadir and HAND, including demographic and HIV disease characteristics, were assessed in univariate and multivariate analyses.
The median CD4 nadir (cells/μl) was 172, and 52% had NPI. Among impaired participants, 603 (75%) had HAND. Higher CD4 nadirs were associated with lower odds of NPI such that for every 5-unit increase in square-root CD4 nadir, the odds of NPI were reduced by 10%. In 589 virally suppressed participants on ART, higher CD4 nadir was associated with lower odds of NPI after adjusting for demographic and clinical factors.
As the risk of NPI was lowest in patients whose CD4 cell count was never allowed to fall to low levels before CART initiation, our findings suggest that initiation of CART as early as possible might reduce the risk of developing HAND, the most common source of NPI among HIV-infected individuals.
Persistent inflammation occurs in people with HIV (PWH) and has many downstream adverse effects including myocardial infarction, neurocognitive impairment and death. Because the proportion of people ...with HIV who use cannabis is high and cannabis may be anti-inflammatory, it is important to characterize the impact of cannabis use on inflammation specifically in PWH. We performed a selective, non-exhaustive review of the literature on the effects of cannabis on inflammation in PWH. Research in this area suggests that cannabinoids are anti-inflammatory in the setting of HIV. Anti-inflammatory actions are mediated in many cases through effects on the endocannabinoid system (ECS) in the gut, and through stabilization of gut-blood barrier integrity. Cannabidiol may be particularly important as an anti-inflammatory cannabinoid. Cannabis may provide a beneficial intervention to reduce morbidity related to inflammation in PWH.
Combination antiretroviral therapy (CART) has greatly reduced medical morbidity and mortality with HIV infection, but high rates of HIV-associated neurocognitive disorders (HAND) continue to be ...reported. Because large HIV-infected (HIV+) and uninfected (HIV−) groups have not been studied with similar methods in the pre-CART and CART eras, it is unclear whether CART has changed the prevalence, nature, and clinical correlates of HAND. We used comparable methods of subject screening and assessments to classify neurocognitive impairment (NCI) in large groups of HIV + and HIV − participants from the pre-CART era (1988–1995;
N
= 857) and CART era (2000–2007;
N
= 937). Impairment rate increased with successive disease stages (CDC stages A, B, and C) in both eras: 25%, 42%, and 52% in pre-CART era and 36%, 40%, and 45% in CART era. In the medically asymptomatic stage (CDC-A), NCI was significantly more common in the CART era. Low nadir CD4 predicted NCI in both eras, whereas degree of current immunosuppression, estimated duration of infection, and viral suppression in CSF (on treatment) were related to impairment only pre-CART. Pattern of NCI also differed: pre-CART had more impairment in motor skills, cognitive speed, and verbal fluency, whereas CART era involved more memory (learning) and executive function impairment. High rates of mild NCI persist at all stages of HIV infection, despite improved viral suppression and immune reconstitution with CART. The consistent association of NCI with nadir CD4 across eras suggests that earlier treatment to prevent severe immunosuppression may also help prevent HAND. Clinical trials targeting HAND prevention should specifically examine timing of ART initiation.
Despite management with opioids and other pain modifying therapies, neuropathic pain continues to reduce the quality of life and daily functioning in HIV-infected individuals. Cannabinoid receptors ...in the central and peripheral nervous systems have been shown to modulate pain perception. We conducted a clinical trial to assess the impact of smoked cannabis on neuropathic pain in HIV. This was a phase II, double-blind, placebo-controlled, crossover trial of analgesia with smoked cannabis in HIV-associated distal sensory predominant polyneuropathy (DSPN). Eligible subjects had neuropathic pain refractory to at least two previous analgesic classes; they continued on their prestudy analgesic regimens throughout the trial. Regulatory considerations dictated that subjects smoke under direct observation in a hospital setting. Treatments were placebo and active cannabis ranging in potency between 1 and 8% Delta-9-tetrahydrocannabinol, four times daily for 5 consecutive days during each of 2 treatment weeks, separated by a 2-week washout. The primary outcome was change in pain intensity as measured by the Descriptor Differential Scale (DDS) from a pretreatment baseline to the end of each treatment week. Secondary measures included assessments of mood and daily functioning. Of 127 volunteers screened, 34 eligible subjects enrolled and 28 completed both cannabis and placebo treatments. Among the completers, pain relief was greater with cannabis than placebo (median difference in DDS pain intensity change, 3.3 points, effect size=0.60; p=0.016). The proportions of subjects achieving at least 30% pain relief with cannabis versus placebo were 0.46 (95%CI 0.28, 0.65) and 0.18 (0.03, 0.32). Mood and daily functioning improved to a similar extent during both treatment periods. Although most side effects were mild and self-limited, two subjects experienced treatment-limiting toxicities. Smoked cannabis was generally well tolerated and effective when added to concomitant analgesic therapy in patients with medically refractory pain due to HIV DSPN.
Despite treatment with virologically suppressive antiretroviral therapy (ART), neurocognitive impairment may persist or develop de novo in aging HIV-infected individuals. We evaluated advancing age ...as a predictor of neurocognitive impairment in a large cohort of previously ART-naive individuals on long-term ART.
The AIDS Clinical Trials Group Longitudinal Linked Randomized Trials was a prospective cohort study of HIV-infected individuals originally enrolled in randomized ART trials. This analysis examined neurocognitive outcomes at least 2 years after ART initiation.
All participants underwent annual neurocognitive testing consisting of Trail making A and B, the wechsler adult intelligence scale-revised Digit Symbol and Hopkins Verbal Learning Tests. Uni and multivariable repeated measures regression models evaluated factors associated with neurocognitive performance. Predictors at parent study entry (ART naive) included entry demographics, smoking, injection drug use, hepatitis B surface antigen, hepatitis C virus serostatus, history of stroke, ART regimen type, pre-ART nadir CD4 cell count, and plasma viral load and as well as time-updated plasma viral load and CD4 cell count.
The cohort comprised 3313 individuals with median pre-ART age of 38 years, 20% women; 36% Black, non-Hispanic; 22% Hispanic. Virologic suppression was maintained at 91% of follow-up visits. Neurocognitive performance improved with years of ART. After adjusting for the expected effects of age using norms from HIV-negative individuals, the odds of neurocognitive impairment at follow-up visits among the HIV infected increased by nearly 20% for each decade of advancing age.
Despite continued virologic suppression and neurocognitive improvement in the cohort as a whole, older individuals were more likely to have neurocognitive impairment than younger individuals.
Abstract
Background
Age-related comorbidities accumulate faster in people with HIV (PWH) than in those without HIV. We evaluated whether a validated multimorbidity scale, the Charlson index, ...predicted neurocognitive trajectories in PWH.
Methods
Scaled scores of a comprehensive neuropsychological battery were averaged across all visits. Multilevel modeling examined between- and within-person predictors of global neurocognition. At the between-person level, averaged Charlson scores were examined as a predictor of neurocognitive change rate, covarying for HIV disease characteristics. Within-persons, visit-specific Charlson index was used to predict fluctuations in global neurocognition at the same and next visit, covarying for disease measures.
Results
Participants were 1195 PWH (mean baseline age: 43.0; SD: 9.7 years) followed for a mean of 7.1 years (range: 0.5–20.5). At the between-person level, more rapid neurocognitive worsening correlated with higher (worse) average Charlson scores (standardized β: −0.062; SE: 0.015; P = .001) and lower CD4 nadir (standardized β: 0.055; SE: 0.021; P = .011), but not viral suppression or average CD4+ lymphocytes (P > .05). At the within-person level, poorer visit-specific neurocognition was related to worse concurrent, but not preceding, Charlson scores (standardized β: −0.046; SE: 0.015; P = .003), detectable HIV viral load (standardized β: 0.018; SE: 0.006; P = .001), and higher CD4+ (standardized β: 0.043; SE: 0.009; P < .001).
Conclusions
The impact of comorbidities on neurocognitive decline exceeded that of HIV disease factors. Although correlative, the temporal relationships suggested that treatment of comorbidities might improve neurocognitive prognosis for PWH.
Medical multimorbidities in this cohort of people with human immunodeficiency virus (PWH) accumulated at a high rate and were strongly associated with faster rates of neurocognitive decline. Findings suggest that interventions to prevent or ameliorate comorbidities may improve neurocognitive prognosis for PWH.
To estimate neuropathic sign/symptom rates with initiation of combination antiretroviral therapy (cART) in HIV-infected ART-naive patients, and to investigate risk factors for: peripheral neuropathy ...and symptomatic peripheral neuropathy (SPN), recovery from peripheral neuropathy/SPN after neurotoxic ART (nART) discontinuation, and the absence of peripheral neuropathy/SPN while on nART.
AIDS Clinical Trials Group (ACTG) Longitudinal Linked Randomized Trial participants who initiated cART in randomized trials for ART-naive patients were annually screened for symptoms/signs of peripheral neuropathy. ART use and disease characteristics were collected longitudinally.
Peripheral neuropathy was defined as at least mild loss of vibration sensation in both great toes or absent/hypoactive ankle reflexes bilaterally. SPN was defined as peripheral neuropathy and bilateral symptoms. Generalized estimating equation logistic regression was used to estimate associations.
Two thousand, one hundred and forty-one participants were followed from January 2000 to June 2007. Rates of peripheral neuropathy/SPN at 3 years were 32.1/8.6% despite 87.1% with HIV-1RNA 400 copies/ml or less and 70.3% with CD4 greater than 350 cells/μl. Associations with higher odds of peripheral neuropathy included older patient age and current nART use. Associations with higher odds of SPN included older patient age, nART use, and history of diabetes mellitus. Associations with lower odds of recovery after nART discontinuation included older patient age. Associations with higher odds of peripheral neuropathy while on nART included older patient age and current protease inhibitor use. Associations with higher odds of SPN while on nART included older patient age, history of diabetes, taller height, and protease inhibitor use.
Signs of peripheral neuropathy remain despite virologic/immunologic control but frequently occurs without symptoms. Aging is a risk factor for peripheral neuropathy/SPN.
Differences in antiretroviral distribution into the central nervous system (CNS) may impact neurocognitive status. We assessed the relationship between estimates of antiretroviral therapy penetration ...into the CNS, using a published ranking system, and neurocognitive status in HIV-positive participants with plasma HIV-1 RNA (vRNA) suppression.
Participants with at least 6 weeks ongoing antiretroviral drug use and vRNA less than 50 copies/ml (N = 2636; 83% male, median baseline CD4 T cells: 244 cells/μl) had at least one neuroscreen assessment Trail Making Test, Part A and B; Wechsler Adult Intelligence Scale-Revised (WAIS-R) Digit Symbol at 10 413 neurovisits. Neuroscreen test scores were demographically adjusted and converted to Z-scores (NPZ3: lower scores imply more impairment). Central nervous system penetration effectiveness (CPE) ranks of 0.0 (low), 0.5 (medium), or 1.0 (high) were assigned to antiretrovirals and summed per regimen, per neurovisit.
Multivariate linear regression models using generalized estimating equations assessed NPZ3 scores with respect to antiretroviral regimen. Covariates were retained if P ≤ 0.1.
A final model demonstrated that better NPZ3 scores were associated with higher CPE among participants taking more than three antiretroviral drugs (+0.07 per one unit increase in CPE score; P = 0.004) but not among participants with three or less antiretroviral drugs in the regimen (+0.01; P = 0.5). Results were adjusted for demographics, injection drug use, hepatitis C virus serostatus, CD4 cell count (current and nadir), baseline vRNA, antiretroviral experience, and years since first antiretroviral drug use.
Use of antiretroviral drugs with better estimated CNS penetration may be associated with better neurocognitive functioning; some people may require more than three antiretroviral drugs to treat HIV in the CNS. Clinically this means antiretroviral regimens could be designed to optimize estimated CNS penetration without sacrificing virologic and immunologic benefits.
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