Evidence for a novel subcortical mechanism for posterior cingulate cortex atrophy in HIV peripheral neuropathy.

We previously reported that neuropathic pain was associated with smaller posterior cingulate cortical (PCC) volumes, suggesting that a smaller/dysfunctional PCC may contribute to development of pain via impaired mind wandering. A gap in our previous report was lack of evidence for a mechanism for the genesis of PCC atrophy in HIV peripheral neuropathy. Here we investigate if volumetric differences in the subcortex for those with neuropathic paresthesia may contribute to smaller PCC volumes, potentially through deafferentation of ascending white matter tracts resulting from peripheral nerve damage in HIV neuropathy. Since neuropathic pain and paresthesia are highly correlated, statistical decomposition was used to separate pain and paresthesia symptoms to determine which regions of brain atrophy are associated with both pain and paresthesia and which are associated separately with pain or paresthesia. HIV+ individuals (N = 233) with and without paresthesia in a multisite study underwent structural brain magnetic resonance imaging. Voxel-based morphometry and a segmentation/registration tool were used to investigate regional brain volume changes associated with paresthesia. Analysis of decomposed variables found that smaller midbrain and thalamus volumes were associated with paresthesia rather than pain. However, atrophy in the PCC was related to both pain and paresthesia. Peak thalamic atrophy (p = 0.004; MNI x = - 14, y = - 24, z = - 2) for more severe paresthesia was in a region with reciprocal connections with the PCC. This provides initial evidence that smaller PCC volumes in HIV peripheral neuropathy are related to ascending white matter deafferentation caused by small fiber damage observed in HIV peripheral neuropathy.

Randomized Controlled Trial of Nurse-Delivered Cognitive-Behavioral Therapy Versus Supportive Psychotherapy Telehealth Interventions for Chronic Back Pain.

This study evaluated a nurse-delivered, telehealth intervention of cognitive-behavioral therapy (CBT) versus supportive psychotherapy for chronic back pain. Participants (N = 61) had chronic back pain (pain "daily" ≥6 months at an intensity of ≥4 of 10 scale) and were randomized to an 8-week, 12-session, CBT or to supportive care (SC) matched for frequency, format, and time, with each treatment delivered by a primary care nurse. The primary outcome was the Roland Morris Disability Questionnaire (RMDQ). Secondary outcomes included the numeric rating scale (NRS) and the Patient Global Impressions Scale (CGI). CBT participants (n = 30) showed significant improvements on the RMDQ (mean = 11.4 [SD = 5.9] vs 9.4 [SD = 6.1] at baseline and post-treatment, respectively, P < .05; d = .33), NRS (mean = 4.9 [SD = 2.1] vs 4.0 [SD = 1.9], respectively, P < .05; d = .45), and on the CGI (39.1% reporting "much improved" or "very much improved"). SC participants (n = 31) also showed significant improvements on the RMDQ (mean = 11.1 [SD = 5.4] vs 9.1 [SD = 5.2], respectively, P < .05; d = .38), the NRS, (mean = 5.0 [SD = 1.9] vs 3.8 [SD = 2.1], respectively, P < .05; d = .60), and 26.7% reporting "much improved" or "very much improved" on the CGI. Between groups comparisons of CBT and SC showed no differences on the study outcomes (Ps > .10). The results suggest that telehealth, nurse-delivered CBT, and SC treatments for chronic back pain can offer significant and relatively comparable benefits. PERSPECTIVE: This article describes the benefits of training primary care nurses to deliver evidence-based behavioral therapies for low back pain. Because of the high prevalence of chronic pain and the growing emphasis on nonopioid therapies, training nurses to provide behavior therapies could be a cost-effective way to improve pain management.

Randomized Controlled Trial of Telephone-delivered Cognitive Behavioral Therapy Versus Supportive Care for Chronic Back Pain.

OBJECTIVE: The objective of this study was to evaluate the efficacy of a telephone-delivered, home-based cognitive-behavioral intervention for chronic low back pain in comparison to a matched supportive care (SC) treatment. METHODS: Participants (N=66) were patients with chronic back pain that were randomized to either an 8-week Cognitive-Behavioral Therapy (CBT) or a SC condition matched for contact frequency, format, and time. Participants completed validated measures of improvement in back pain disability, pain severity, and overall improvement. RESULTS: Intent-to-treat analyses at posttreatment showed that the treatment groups not show significantly different improvements in back pain disability (mean changes, -2.4 and -2.6 for CBT and SC, respectively; Cohen d, 0.49 and 0.55, respectively) or reductions in pain severity (mean changes, -0.9 and -1.4 for CBT and SC respectively; Cohen d, 0.50, and 0.90, respectively). Participants rated their overall improvement levels at 31% (CBT) versus 18.5% (SC). DISCUSSION: Results from this clinical trial suggest that home-based, telephone-delivered CBT and SC treatments did not significantly differ in their benefits for back pain severity and disability, and may warrant further research for applications to hospital settings. Major limitations included recruitment difficulties that underpowered primary analyses, the lack of objective improvement measures, and the absence of a usual care/untreated control group for comparisons.

Risks and predictors of current suicidality in HIV-infected heroin users in treatment in Yunnan, China: a controlled study.

OBJECTIVE: Suicide is an important public health problem in China. Elsewhere, injection drug use and HIV infection have independently been associated with suicidality, but research has often overlooked these high-risk groups in China. We determined the frequency and predictors of suicidal ideas in Chinese HIV-infected (HIV(+)) and HIV-uninfected (HIV(-)) heroin injection drug users (IDUs) in treatment and a control sample. We hypothesized that rates of suicidal ideas would be significantly higher among IDUs compared with controls and highest among HIV IDUs. METHOD: We assessed suicidal ideas within the past 2 weeks in HIV(+) (n = 204) and HIV(-) (n = 202) heroin IDUs in methadone treatment in Yunnan, a province at the intersection of the heroin and HIV epidemics, and in demographically matched HIV non-drug-using controls (n = 201). RESULTS: Rates of suicidality were higher in IDUs than controls, but there was no additive effect of HIV infection (HIV(+) IDU: 43.1%; HIV(-) IDU: 37.1%; controls: 8.5%). Among HIV(+) IDUs, suicidality was associated most strongly with a combination of prior history of major depression, low perceived social support, and experience of HIV-relevant stress, but not with AIDS diagnosis. Among HIV(-) IDUs, suicidality was associated with prior history of major depressive or alcohol use disorder. Less than 25% of IDUs with suicidality had histories of mood or alcohol use diagnoses. CONCLUSION: Because suicidal ideation is frequent in IDUs in China, regardless of HIV status, and is not fully accounted for by past psychiatric history, additional research may be warranted.

Neurocognitive impact of substance use in HIV infection.

BACKGROUND: : To determine how serious a confound substance use (SU) might be in studies on HIV-associated neurocognitive disorder (HAND), we examined the relationship of SU history to neurocognitive impairment (NCI) in participants enrolled in the Central Nervous System HIV Antiretroviral Therapy Effects Research study. METHODS: : After excluding cases with behavioral evidence of acute intoxication and histories of factors that independently could account for NCI (eg, stroke), baseline demographic, medical, SU, and neurocognitive data were analyzed from 399 participants. Potential SU risk for NCI was determined by the following criteria: lifetime SU Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition diagnosis, self-report of marked lifetime SU, or positive urine toxicology. Participants were divided into 3 groups as follows: no SU (n = 134), nonsyndromic SU (n = 131), syndromic SU (n = 134) and matched on literacy level, nadir CD4, and depressive symptoms. RESULTS: : Although approximately 50% of the participants were diagnosed with HAND, a multivariate analysis of covariance of neurocogntive summary scores, covarying for urine toxicology, revealed no significant effect of SU status. Correlational analyses indicated weak associations between lifetime heroin dosage and poor recall and working memory and between cannabis and cocaine use and better verbal fluency. CONCLUSIONS: : These data indicate that HIV neurocognitive effects are seen at about the same frequency in those with and without historic substance abuse in cases that are equated on other factors that might contribute to NCI. Therefore, studies on neuroAIDS and its treatment need not exclude such cases. However, the effects of acute SU and current SU disorders on HAND require further study.

HIV-associated neurocognitive disorders before and during the era of combination antiretroviral therapy: differences in rates, nature, and predictors.

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.

Psychiatric disorders and risk of transition to chronicity in men with first onset low back pain.

OBJECTIVE: To assess whether pre-existing psychiatric diagnoses increase the likelihood of transitioning from sub-acute to chronic back pain. DESIGN: Prospective cohort study. METHODS: Men (N = 140) experiencing a first onset of low back pain (LBP) were examined for lifetime psychiatric disorders approximately 8 weeks post pain-onset using the Diagnostic Interview Schedule (DIS-III-R), then re-evaluated at 6 months after pain onset to determine who did or did not progress to pain chronicity. OUTCOME MEASURE: Transition to chronic pain and disability was based on 6-month self-report measures of pain intensity and perceived disability. RESULTS: Men with a pre-pain lifetime diagnosis of major depressive disorder had 5 times greater risk of transitioning to chronic LBP (odds ratio [OR] = 4.99; 95% confidence interval [CI] 1.49-16.76). Increased risk was also associated with a pre-pain lifetime diagnosis of generalized anxiety (OR = 2.45; 95% CI 1.06-5.68), post-traumatic stress (OR = 3.23; 95% CI 1.11-9.44), and with current nicotine dependence (OR = 2.49; 95% CI 1.15-5.40). There were no statistically significant effects for abuse or dependence of alcohol or other psychoactive substances. DISCUSSION: Lifetime history of major depression or a major anxiety disorder may represent potential psychosocial "yellow flags" for the transition to chronicity in men with first-onset LBP. Screening for lifetime depressive or anxiety disorders may identify individuals at higher risk, who may benefit from referral for more intensive rehabilitation.

Longer term improvement in neurocognitive functioning and affective distress among methamphetamine users who achieve stable abstinence.

Chronic use of methamphetamine (MA) is associated with neuropsychological dysfunction and affective distress. Some normalization of function has been reported after abstinence, but little in the way of data is available on the possible added benefits of long-term sobriety. To address this, we performed detailed neuropsychological and affective evaluations in 83 MA-dependent individuals at a baseline visit and following an average one-year interval period. Among the 83 MA-dependent participants, 25 remained abstinent, and 58 used MA at least once during the interval period. A total of 38 non-MA-addicted, demographically matched healthy comparison (i.e., HC) participants were also examined. At baseline, both MA-dependent participants who were able to maintain abstinence and those who were not performed significantly worse than the healthy comparison subjects on global neuropsychological functioning and were significantly more distressed. At the one-year follow-up, both the long-term abstainers and healthy comparison groups showed comparable global neuropsychological performance and affective distress levels, whereas the MA-dependent group who continued to use MA were worse than the comparison participants in terms of global neuropsychological functioning and affective distress. An interaction was observed between neuropsychological impairment at baseline, MA abstinence, and cognitive improvement, with abstinent MA-dependent participants who were neuropsychologically impaired at baseline demonstrating significantly and disproportionately greater improvement in processing speed and slightly greater improvement in motor abilities than the other participants. These results suggest partial recovery of neuropsychological functioning and improvement in affective distress upon sustained abstinence from MA that may extend beyond a year or more.

Methamphetamine use parameters do not predict neuropsychological impairment in currently abstinent dependent adults.

Methamphetamine (meth) abuse is increasingly of public health concern and has been associated with neurocognitive dysfunction. Some previous studies have been hampered by background differences between meth users and comparison subjects, as well as unknown HIV and hepatitis C (HCV) status, which can also affect brain functioning. We compared the neurocognitive functioning of 54 meth dependent (METH+) study participants who had been abstinent for an average of 129 days, to that of 46 demographically comparable control subjects (METH-) with similar level of education and reading ability. All participants were free of HIV and HCV infection. The METH+ group exhibited higher rates of neuropsychological impairment in most areas tested. Among meth users, neuropsychologically normal (n=32) and impaired (n=22) subjects did not differ with respect to self-reported age at first use, total years of use, route of consumption, or length of abstinence. Those with motor impairment had significantly greater meth use in the past year, but impairment in cognitive domains was unrelated to meth exposure. The apparent lack of correspondence between substance use parameters and cognitive impairment suggests the need for further study of individual differences in vulnerability to the neurotoxic effects of methamphetamine.

Smoked medicinal cannabis for neuropathic pain in HIV: a randomized, crossover clinical trial.

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.

Dose-dependent effects of smoked cannabis on capsaicin-induced pain and hyperalgesia in healthy volunteers.

BACKGROUND: Although the preclinical literature suggests that cannabinoids produce antinociception and antihyperalgesic effects, efficacy in the human pain state remains unclear. Using a human experimental pain model, the authors hypothesized that inhaled cannabis would reduce the pain and hyperalgesia induced by intradermal capsaicin. METHODS: In a randomized, double-blinded, placebo-controlled, crossover trial in 15 healthy volunteers, the authors evaluated concentration-response effects of low-, medium-, and high-dose smoked cannabis (respectively 2%, 4%, and 8% 9-delta-tetrahydrocannabinol by weight) on pain and cutaneous hyperalgesia induced by intradermal capsaicin. Capsaicin was injected into opposite forearms 5 and 45 min after drug exposure, and pain, hyperalgesia, tetrahydrocannabinol plasma levels, and side effects were assessed. RESULTS: Five minutes after cannabis exposure, there was no effect on capsaicin-induced pain at any dose. By 45 min after cannabis exposure, however, there was a significant decrease in capsaicin-induced pain with the medium dose and a significant increase in capsaicin-induced pain with the high dose. There was no effect seen with the low dose, nor was there an effect on the area of hyperalgesia at any dose. Significant negative correlations between pain perception and plasma delta-9-tetrahydrocannabinol levels were found after adjusting for the overall dose effects. There was no significant difference in performance on the neuropsychological tests. CONCLUSIONS: This study suggests that there is a window of modest analgesia for smoked cannabis, with lower doses decreasing pain and higher doses increasing pain.

Efficacy of noradrenergic and serotonergic antidepressants in chronic back pain: a preliminary concentration-controlled trial.

OBJECTIVE: Although antidepressants are widely prescribed as analgesics in chronic back pain, their clinical pharmacology is not well established. Norepinephrine transporter blockade seems to be essential for analgesia, but optimal concentrations are unknown. Fixed-dose studies of serotonin reuptake inhibitors are generally negative, but such studies cannot be interpreted clearly because efficacy might be detected if concentration-response relationships were known. We evaluated (1) the feasibility of conducting a controlled-concentration study of a norepinephrine (desipramine) and a serotonin reuptake (fluoxetine) inhibitor and (2) the relationship between achieved concentrations and analgesic response. METHODS: This single-center, 12-week, double-blind, prospective, controlled-concentration study randomized 121 chronic back pain patients without major depression to active placebo (benztropine mesylate) or to predetermined low, medium, or high concentrations of desipramine (targets were 50, 110, and 150 ng/mL, respectively) or fluoxetine (targets were 100, 200, and 400 ng/mL, respectively). Of these, 83 completed the trial: 38 withdrew primarily due to side effects. RESULTS: Manipulation check revealed significant overlap of assigned and achieved concentrations related to drug intolerability. Completers' analysis of achieved concentrations revealed reduction in pain intensity was significantly greater for low-concentration desipramine (<60 ng/mL, mean Descriptor Differential Scale [DDS], 4.5) compared with placebo (DDS 6.2), higher concentrations of desipramine (>60 ng/mL, DDS 7.9), and all concentrations of fluoxetine (P < 0.05, DDS 7.1). Significant improvement in everyday function mirrored findings for pain intensity. CONCLUSIONS: Preliminary evidence for a low-concentration "therapeutic window" for noradrenergic analgesia may warrant additional study.

Screening for major depression in persons with HIV infection: the concurrent predictive validity of the Profile of Mood States Depression-Dejection Scale.

Major Depressive Disorder (MDD) is among the most prevalent but underdiagnosed psychiatric disorders in persons with HIV infection. Given the known adverse impact of comorbid MDD on HIV disease progression and health-related quality of life, it is important both for research and for efficient, effective clinical care, to validate existing screening measures that may discriminate between MDD and the somatic symptoms of HIV (such as fatigue). In the current study, we evaluated the concurrent predictive validity of the Profile of Mood States (POMS) Depression-Dejection scale in detecting current MDD in 310 persons with HIV infection. The Structured Clinical Interview for DSM-IV (SCID) diagnosis of MDD and the Cognitive-Affective scale from the Beck Depression Inventory (BDI-CA) served as comparative diagnostic and severity measures of depression, respectively. Results demonstrated that the POMS Depression-Dejection scale accurately classified persons with and without MDD SCID diagnoses, with an overall hit rate of 80%, sensitivity of 55%, specificity of 84%, and negative predictive power of 91% using a recommended cutpoint of 1.5 standard deviations above the normative mean. Moreover, the POMS performed comparably to the BDI-CA in classifying MDD. Findings support the predictive validity of the POMS Depression-Dejection scale as a screening instrument for MDD in persons with HIV disease.