How helpful are the European AIDS Clinical Society cognitive screening questions in predicting cognitive impairment in an aging, well-treated HIV-positive population?

OBJECTIVES: Diagnosing neurocognitive impairment (NCI) in HIV infection requires time-consuming neuropsychological assessment. Screening tools are needed to identify when neuropsychological referral is indicated. We examined the positive and negative predictive values (PPVs and NPVs, respectively) of the three European AIDS Clinical Society (EACS) screening questions in identifying NCI. METHODS: The Neurocognitive Assessment in the Metabolic and Aging Cohort (NAMACO) study recruited patients aged ≥45 years enrolled in the Swiss HIV Cohort Study between 1 May 2013 and 30 November 2016. NAMACO participants (1) answered EACS screening questions, (2) underwent standardized neuropsychological assessment and (3) completed self-report forms [Center for Epidemiologic Studies Depression Scale (CES-D)] rating mood. NCI categories were defined using Frascati criteria. PPVs and NPVs of the EACS screening questions in identifying NCI categories were calculated. RESULTS: Of 974 NAMACO participants with complete EACS screening question data, 244 (25.1%) expressed cognitive complaints in answer to at least one EACS screening question, of whom 51.3% had NCI (26.1% HIV-associated and 25.2% related to confounding factors). The PPV and NPV of the EACS screening questions in identifying HIV-associated NCI were 0.35 and 0.7, respectively. Restricting analysis to NCI with functional impairment or related to confounding factors, notably depression, the NPV was 0.90. Expressing cognitive complaints for all three EACS screening questions was significantly associated with depression (P < 0.001). CONCLUSIONS: The EACS screening questions had an NPV of 0.7 for excluding patients with HIV-associated NCI as defined by Frascati criteria. The PPV and NPV may improve if NCI diagnoses are based on new criteria.

The Neurocognitive Assessment in the Metabolic and Aging Cohort (NAMACO) study: baseline participant profile.

OBJECTIVES: The aim of the study was to examine baseline neurocognitive impairment (NCI) prevalence and factors associated with NCI among patients enrolled in the Neurocognitive Assessment in the Metabolic and Aging Cohort (NAMACO) study. METHODS: The NAMACO study is an ongoing, prospective, longitudinal, multicentre and multilingual (German, French and Italian) study within the Swiss HIV Cohort Study. Between 1 May 2013 and 30 November 2016, 981 patients ≥ 45 years old were enrolled in the study. All underwent standardized neuropsychological (NP) assessment by neuropsychologists. NCI was diagnosed using Frascati criteria and classified as HIV-associated or as related to other factors. Dichotomized analysis (NCI versus no NCI) and continuous analyses (based on NP test z-score means) were performed. RESULTS: Most patients (942; 96.2%) had viral loads < 50 HIV-1 RNA copies/mL. NCI was identified in 390 patients (39.8%): 263 patients (26.8%) had HIV-associated NCI [249 patients (25.4%) had asymptomatic neurocognitive impairment (ANI)] and 127 patients (13%) had NCI attributable to other factors, mainly psychiatric disorders. There was good correlation between dichotomized and continuous analyses, with NCI associated with older age, non-Caucasian ethnicity, shorter duration of education, unemployment and longer antiretroviral therapy duration. CONCLUSIONS: In this large sample of aging people living with HIV with well-controlled infection in Switzerland, baseline HIV-associated NCI prevalence, as diagnosed after formal NP assessment, was 26.8%, with most cases being ANI. The NAMACO study data will enable longitudinal analyses within this population to examine factors affecting NCI development and course.

Long-term stability of phase-separated half-Heusler compounds.

Half-Heusler (HH) compounds have shown high figure of merit up to 1.5. Here, we address the long-term stability of n- and p-type HH materials. For this purpose, we investigated HH materials based on the Ti0.3Zr0.35Hf0.35NiSn-system after 500 cycles (1700 h) from 373 to 873 K. Both compounds exhibit a maximum Seebeck coefficient of |α|≈ 210 µV K(-1) and a phase separation into two HH phases. The dendritic microstructure is temperature resistant and upon cycling the changes in the microstructure are so marginal that the low thermal conductivity values (κ < 4 W m(-1) K(-1)) could be maintained. Our results emphasize that phase-separated HH compounds are suitable low cost materials and can lead to enhanced thermoelectric efficiencies beyond the set benchmark for industrial applications.

Microlaparoscopy for recurrent abdominal pain in children.

PURPOSE: This prospective study evaluated the diagnostic and therapeutic feasibility and safety of microlaparoscopy for the management of chronic abdominal pain in children. METHODS: The study included 45 children (13 boys and 32 girls; age range from 6 to 16 years, average 9.5 years) undergoing diagnostic microlaparoscopy for chronic abdominal pain. Microlaparoscopy (the exclusive use of 2 mm instrument sets and small diameter scopes, i. e. 1.7 mm, 1.9 mm and 2.4 mm) was performed after common organic diseases were ruled out by careful baseline investigations. RESULTS: No complications occurred which were related to the exclusive use of 2 mm instruments and small scopes. CT scans were avoided in all patients. No intraoperative pathological findings were found in 18 children. In another 18 children, the intraoperative findings indicated the need for further surgical intervention. At follow-up, 26 patients reported that they were totally pain-free; 10 children had partial resolution after surgery, and 8 children reported only minimal resolution. In 20 cases, the procedures were accomplished as an outpatient surgery. CONCLUSION: Microlaparoscopy seems to be a safe and effective diagnostic tool with a favorable diagnostic accuracy, minimal access trauma and superior cosmesis in children.