Muscle power in children, youth and young adults who acquired HIV perinatally

OBJECTIVES

To compare muscle power between youth who acquired HIV perinatally and HIV unexposed uninfected (HUU) youth.

METHODS

We assessed muscle power (relative to body mass, P_max/mass), muscle force normalized to body weight (F_max/BW), force efficiency, jump height (H_max) and velocity (V_max) during a single two-legged jump with hands on waist on a force platform (Leonardo) in HIV+ youth (n=35, 9-21 y). Thirty-three and 22 participants returned at 12- and 24-months, respectively. We compared age- and sex-specific z-scores in the HIV+ youth to those in HUU controls (n=716, 9-21 y) adjusting for height and muscle cross-sectional area (MCSA, by pQCT).

RESULTS

At baseline, z-scores for Pmax/mass, F_max/BW and V_max were less than 1 standard deviation lower than HUU after adjusting for height and MCSA (p⟨0.05). P_max/mass z-score was negatively associated with level of immunosuppression (p=0.013), but this relationship was not significant after adjusting for height and MCSA (p=0.07). Z-scores for all mechanography outcomes remained stable over time in HIV+ youth.

CONCLUSION

Small deficits in muscle power were apparent in children and youth who acquired HIV perinatally, and the trajectory of muscle power did not change over two years. Further study is needed to identify effective strategies to improve dynamic muscle function in this population.

Bone geometry and strength are adapted to muscle force in children and adolescents perinatally infected with HIV

OBJECTIVES

To determine if bone health is compromised in perinatally HIV-infected youth.

METHODS

We assessed BMC at the proximal femur, lumbar spine and total body using DXA in perinatally HIV-infected youth (n=31; 9-18y). Using pQCT, we assessed muscle CSA, total and cortical bone area, cortical BMD and thickness and strength strain index at the tibial shaft. Thirty and 18 participants returned at 12- and 24-months, respectively. We calculated age- and sex-specific z-scores for the HIV-infected youth using data from a healthy cohort (n=883; 9-18y).

RESULTS

At baseline, height and MCSA were reduced in HIV-infected youth (-0.79 to -0.23, p<0.05). BMC z-scores adjusted for height and lean mass were lower than controls at all sites except the lumbar spine (-0.57 to -0.27, p<0.05). Bone area and strength z-scores were not different from zero after adjusting for tibial length and MCSA. In contrast, cortical BMD z-scores were greater in HIV-infected youth (0.46, p=0.011). Z-scores for all bone outcomes showed positive trends over time in HIV-infected youth.

CONCLUSION

Although HIV infection may be associated with bone mass deficits during growth, bone geometry and strength appear adapted to muscle force. Further, deficits in bone mass may dissipate over time in this population.

[The impact of lesions in the right hemisphere on linguistic skills: theoretical and clinical perspectives]

INTRODUCTION

A lesion of the right hemisphere of right-handers can result in verbal communication impairments. The recent development of theoretical frameworks with regard to discourse and pragmatic abilities, among others, now allows us to recognize and describe these impairments.

AIM

To offer an overview of the verbal communication deficits that can be found in right-hemisphere-damaged individuals. These deficits can interfere, at different levels, with prosody, the semantic processing of words and discourse and pragmatic abilities.

DEVELOPMENT

Such impairments appear to be present in about half of right-hemisphere-damaged patients and, when present, can result in different clinical profiles. These deficits raise the question of their labeling and their relationship with aphasia.

CONCLUSIONS

Given the evolution of the concept of language and the universal definition of aphasia, it is proposed that these deficits correspond to another manifestation of aphasia, thus challenging the idea that they are of a 'non-aphasic' nature.

Lopinavir/Ritonavir Plus Nevirapine as a Nucleoside-Sparing Approach in Antiretroviral-Experienced Patients (NEKA Study)

OBJECTIVES

To compare the efficacy and safety of a nucleoside-sparing approach with a conventional highly active antiretroviral therapy (HAART) regimen in antiretroviral-experienced patients with prolonged viral suppression.

METHODS

Pilot study including 31 antiretroviral-experienced patients with HIV RNA <80 copies/mL. Subjects were randomly assigned to lopinavir/ritonavir (LPV/rtv) 400/100 mg BID plus nevirapine (NVP) 200 mg BID (NVP group, n = 16) or LPV/rtv plus the 2 previous NRTIs (NRTI group, n = 15). The primary endpoint was the percentage of subjects who maintained viral suppression at week 48. Changes in lipid metabolism, mitochondrial parameters, and LPV trough levels were also assessed.

RESULTS

All patients maintained viral suppression after 48 weeks. No subject discontinued therapy because of adverse events. HDL cholesterol increased by 28% at week 24 (P < 0.0001) and 10% after 48 weeks of follow-up (P = 0.319) in the NVP group. In the NRTI group, LDL cholesterol increased by 14% at week 48 (P = 0.076). Mitochondrial DNA/nuclear DNA ratio and mitochondrial respiratory chain complex IV activity showed a trend toward increasing in the NVP group. Mean (SD) LPV trough levels were 6340 (2129) ng/mL in the NRTI group and 5161 (2703) ng/mL in the NVP group (P = 0.140).

CONCLUSIONS

In antiretroviral-experienced subjects with sustained viral suppression, dual therapy with NVP plus LPV/rtv at standard dosage was as potent and safe as standard-of-care HAART at 48 weeks of follow-up. This approach may reduce mitochondrial toxicity and improve LPV/rtv-associated lipid abnormalities. The results of this pilot study support the study of this approach in a larger, randomized trial.

Alternation of antiretroviral drug regimens for HIV infection. Efficacy, safety and tolerability at week 96 of the Swatch Study

INTRODUCTION

Alternation of antiretroviral drug regimens has been proposed as a novel treatment strategy for HIV infection. However, some concerns persist regarding antiviral efficacy, adherence, toxicity and resistance evolution in the long term.

METHODS

A total of 161 antiretroviral-naive HIV-1-infected patients were randomized to receive stavudine/didanosine/efavirenz (group A) or zidovudine/lamivudine/ nelfinavir (group B) or to alternate between the two regimens every 3 months starting with regimen A (group C). Antiviral efficacy, adherence, safety and tolerability were analysed every 12 weeks.

RESULTS

After 96 weeks, time to virological failure was significantly delayed in the alternating regimen compared with the standards of care regimens. Virological suppression was seen in 46%, 48% and 58% of patients in groups A, B and C, respectively, in the intention-to-treat analysis and in 75%, 76% and 97% in the on-treatment analysis (A vs C: P=0.014; B vs C: P=0.016; A vs B: P=0.849). At the end of the study, 94% of patients in group A and 92% in groups B and C reported an adherence greater than 95%. Alternating therapy was associated with a similar impact on CD4+ counts in comparison with the standards of care regimens, as well as a lower mitochondrial DNA/nuclear DNA (mtDNA/nDNA) ratio decrease in the mitochondrial substudy performed on 37 patients. The frequency and intensity of adverse events in the alternating group decreased during subsequent cycles.

DISCUSSION

Our results favour the hypothesis that proactive therapy switching may delay the accumulation of resistance mutations. Moreover, the alternating regimen was well tolerated and adherence remained comparably high in all treatment groups. The lower mtDNA/nDNA ratio decrease observed in this group may imply a lower impact on mitochondrial toxicity than in standard regimens.

Alternation of Antiretroviral Drug Regimens for HIV Infection. Efficacy, Safety and Tolerability at Week 96 of the Swatch Study

Introduction

Alternation of antiretroviral drug regimens has been proposed as a novel treatment strategy for HIV infection. However, some concerns persist regarding antiviral efficacy, adherence, toxicity and resistance evolution in the long term.

Methods

A total of 161 antiretroviral-naive HIV-1-infected patients were randomized to receive stavudine/ didanosine/efavirenz (group A) or zidovudine/lamivudine/ nelfinavir (group B) or to alternate between the two regimens every 3 months starting with regimen A (group C). Antiviral efficacy, adherence, safety and tolerability were analysed every 12 weeks.

Results

After 96 weeks, time to virological failure was significantly delayed in the alternating regimen compared with the standards of care regimens. Virological suppression was seen in 46%, 48% and 58% of patients in groups A, B and C, respectively, in the intention-to-treat analysis and in 75%, 76% and 97% in the on-treatment analysis (A vs C: P=0.014; B vs C: P=0.016; A vs B: P=0.849). At the end of the study, 94% of patients in group A and 92% in groups B and C reported an adherence greater than 95%. Alternating therapy was associated with a similar impact on CD4+ counts in comparison with the standards of care regimens, as well as a lower mitochondrial DNA/nuclear DNA (mtDNA/nDNA) ratio decrease in the mitochondrial substudy performed on 37 patients. The frequency and intensity of adverse events in the alternating group decreased during subsequent cycles.

Discussion

Our results favour the hypothesis that proactive therapy switching may delay the accumulation of resistance mutations. Moreover, the alternating regimen was well tolerated and adherence remained comparably high in all treatment groups. The lower mtDNA/nDNA ratio decrease observed in this group may imply a lower impact on mitochondrial toxicity than in standard regimens.

Circadian variations in the pharmacokinetics of a new microemulsion formulation of cyclosporine in cardiac transplant recipients

We attempted to characterize circadian variations in pharmacokinetic parameters of a new formulation of cyclosporine (CsA) in nine cardiac allograft recipients. A secondary objective was to determine the sampling time that correlated best with exposure of patients to the drug. This was a two-period study with each period lasting 12 hours. All patients received two equal doses of a new microemulsion of CsA 12 hours apart. Blood samples to measure drug levels were obtained at administration and 1, 2, 3, 4, 6, 9, and 12 hours after each dose. We found no statistically significant difference in pharmacokinetic parameters (areas under the curve, minimum blood concentration, oral clearance) measured during the day and during the night. However, maximum blood concentrations during the day were 30% higher than those at night (p<0.05). We found a good correlation between minimum concentrations in the morning and overall exposure of patients to CsA (r=0.89). This new microemulsion appears to have few circadian variations of blood concentrations in cardiac transplant recipients. The clinical significance of higher maximum blood concentration during daytime remains to be elucidated. Our results support the most widely accepted method for monitoring CsA, which is based on minimum concentrations in the morning.