Disease awareness and healthcare utilization in rural South Africa: a comparative analysis of HIV and diabetes in the HAALSI cohort.

BACKGROUND: Studies from rural South Africa indicate that people living with HIV (PLHIV) may have better health outcomes than those without, potentially due to the frequent healthcare visits necessitated by infection. Here, we examined the association between HIV status and healthcare utilization, using diabetes as an illustrative comparator of another high-burden, healthcare-intensive disease. METHODS: Our exposure of interest was awareness of positive disease status for both HIV and diabetes. We identified 742 individuals who were HIV-positive and aware of their status and 305 who had diabetes and were aware of their status. HIV-positive status was further grouped by viral suppression. For each disease, we estimated the association with (1) other comorbid, chronic conditions, (2) health facility visits, (3) household-level healthcare expenditure, and (4) per-visit healthcare expenditure. We used log-binomial regression models to estimate prevalence ratios for co-morbid chronic conditions. Linear regression models were used for all other outcomes. RESULTS: Virally suppressed PLHIV had decreased prevalence of chronic conditions, increased public clinic visits [ß = 0.59, 95% CI: 0.5, 0.7], and reduced per-visit private clinic spending [ß = -60, 95% CI: -83, -6] compared to those without HIV. No differences were observed in hospitalizations and per-visit spending at hospitals and public clinics between virally suppressed PLHIV and non-PLHIV. Conversely, diabetic individuals had increased prevalence of chronic conditions, increased visits across facility types, increased household-level expenditures (ß = 88 R, 95% CI: 29, 154), per-visit hospital spending (ß = 54 R, 95% CI: 7, 155), and per-visit public clinic spending (ß = 31 R, 95% CI: 2, 74) compared to those without diabetes. CONCLUSIONS: Our results suggest that older adult PLHIV may visit public clinics more often than their HIV-negative counterparts but spend similarly on a per-visit basis. This provides preliminary evidence that the positive health outcomes observed among PLHIV in rural South Africa may be explained by different healthcare engagement patterns. Through our illustrative comparison between PLHIV and diabetics, we show that shifting disease burdens towards chronic and historically underfunded diseases, like diabetes, may be changing the landscape of health expenditure inequities.

Associations between Cortical Thickness and Metamemory in Alzheimer's Disease.

Metacognitive deficits affect Alzheimer's disease (AD) patient safety and increase caregiver burden. The brain areas that support metacognition are not well understood. 112 participants from the Imaging and Genetic Biomarkers for AD (ImaGene) study underwent comprehensive cognitive testing and brain magnetic resonance imaging. A performance-prediction paradigm was used to evaluate metacognitive abilities for California Verbal Learning Test-II learning (CVLT-II 1-5) and delayed recall (CVLT-II DR); Visual Reproduction-I immediate recall (VR-I Copy) and Visual Reproduction-II delayed recall (VR-II DR); Rey-Osterrieth Complex Figure Copy (Rey-O Copy) and delayed recall (Rey-O DR). Vertex-wise multivariable regression of cortical thickness was performed using metacognitive scores as predictors while controlling for age, sex, education, and intracranial volume. Subjects who overestimated CVLT-II DR in prediction showed cortical atrophy, most pronounced in the bilateral temporal and left greater than right (L > R) frontal cortices. Overestimation of CVLT-II 1-5 prediction and DR performance in postdiction showed L > R associations with medial, inferior and lateral temporal and left posterior cingulate cortical atrophy. Overconfident prediction of VR-I Copy performance was associated with right greater than left medial, inferior and lateral temporal, lateral parietal, anterior and posterior cingulate and lateral frontal cortical atrophy. Underestimation of Rey-O Copy performance in prediction was associated with atrophy localizing to the temporal and cingulate areas, and in postdiction, with diffuse cortical atrophy. Impaired metacognition was associated to cortical atrophy. Our results indicate that poor insight into one's cognitive abilities is a pervasive neurodegenerative feature associated with AD across the cognitive spectrum.

Peer review reduces spin in PCORI research reports.

BACKGROUND: The Patient-Centered Outcomes Research Institute (PCORI) is obligated to peer review and to post publicly "Final Research Reports" of all funded projects. PCORI peer review emphasizes adherence to PCORI's Methodology Standards and principles of ethical scientific communication. During the peer review process, reviewers and editors seek to ensure that results are presented objectively and interpreted appropriately, e.g., free of spin. METHODS: Two independent raters assessed PCORI peer review feedback sent to authors. We calculated the proportion of reports in which spin was identified during peer review, and the types of spin identified. We included reports submitted by April 2018 with at least one associated journal article. The same raters then assessed whether authors addressed reviewers' comments about spin. The raters also assessed whether spin identified during PCORI peer review was present in related journal articles. RESULTS: We included 64 PCORI-funded projects. Peer reviewers or editors identified spin in 55/64 (86%) submitted research reports. Types of spin included reporting bias (46/55; 84%), inappropriate interpretation (40/55; 73%), inappropriate extrapolation of results (15/55; 27%), and inappropriate attribution of causality (5/55; 9%). Authors addressed comments about spin related to 47/55 (85%) of the reports. Of 110 associated journal articles, PCORI comments about spin were potentially applicable to 44/110 (40%) articles, of which 27/44 (61%) contained the same spin that was identified in the PCORI research report. The proportion of articles with spin was similar for articles accepted before and after PCORI peer review (63% vs 58%). DISCUSSION: Just as spin is common in journal articles and press releases, we found that most reports submitted to PCORI included spin. While most spin was mitigated during the funder's peer review process, we found no evidence that review of PCORI reports influenced spin in journal articles. Funders could explore interventions aimed at reducing spin in published articles of studies they support.

Neurodegenerative Patterns of Cognitive Clusters of Early-Onset Alzheimer's Disease Subjects: Evidence for Disease Heterogeneity.

BACKGROUND/AIMS: Alzheimer's disease (AD) with onset before 65 (early-onset AD [EOAD]) occurs in approximately 6% of cases and can affect nonmemory domains. Here, we analyze patterns of impairment in amnestic EOAD individuals using data-driven statistical analyses. METHODS: Cognitive data of 146 EOAD subjects were Z-normalized to 395 cognitively normal (CN) individuals. Domain-averaged Z-scores were adjusted for age, sex, and education followed by Wald cluster analysis of residuals. Magnetic resonance imaging and positron emission tomography comparisons of EOAD clusters to age-matched CN were done using Statistic Parametric Mapping 8. Cluster-level-family-wise error (p < 0.05) correction was applied. Mixed-effect models were used to compute longitudinal change across clusters. RESULTS: Scree plot using the pseudo-T-squared suggested a 4-cluster solution. Cluster 1 (memory-predominant impairment) showed atrophy/hypometabolism in medial/lateral temporal, lateral parietal, and posterior cingulate regions. Cluster 2 (memory/visuospatial-predominant) showed atrophy/hypometabolism of medial temporal, temporoparietal, and frontal cortices. Cluster 3 (memory, language, and executive function) and Cluster 4 (globally impaired) manifested atrophy and hypometabolism throughout the brain. Longitudinally between-cluster differences in the visuospatial and language/executive domains were significant, suggesting phenotypic variation. CONCLUSION: We observed significant heterogeneity in cognitive presentation among amnestic EOAD subjects and patterns of atrophy/hypometabolism in each cluster in agreement with the observed cognitive phenotype.