Effects of Semaglutide on Muscle Structure and Function in the SLIM LIVER Study.

BACKGROUND: Semaglutide, a GLP-1 receptor agonist, is highly effective for decreasing weight. Concomitant loss of muscle mass often accompanies weight loss and may have consequences on muscle function. METHODS: This is a secondary analysis from the SLIM LIVER (ACTG A5371) study, a single-arm study of semaglutide in people with HIV (PWH) with metabolic dysfunction-associated steatotic liver disorder (MASLD). Participants received subcutaneous semaglutide for 24 weeks (titrated to 1 mg/week by week 4). Psoas volume and fat fraction were assessed from liver magnetic resonance imaging and physical function by 10-time chair rise test and 4m gait speed. Mean change from baseline to week 24 was estimated with linear regression modeling. RESULTS: 51 PWH enrolled; muscle measures were available from 46 participants. The mean age was 50 (standard deviation [SD] 11) years and BMI 35.5 (5.6) kg/m2, 43% were women, 33% Black, and 39% Hispanic/Latino. Psoas muscle volume decreased by 9.3% (95% confidence interval [CI]: -13.4, -5.2; p<0.001) over 24 weeks but psoas muscle fat did not significantly change (-0.42%, CI: -1.00, 0.17; p=0.16). Chair rise and gait speed had non-significant improvements of 1.27 seconds (CI: -2.7, 0.10) and 0.05 m/sec (CI: -0.01, 0.10), respectively (both p>0.07). The prevalence of slow gait speed (< 1 m/sec) decreased from 63% to 46% (p=0.029). CONCLUSIONS: In PWH receiving low-dose semaglutide for MASLD, despite decreased psoas muscle volume, there was no significant change in physical function. This suggests that function was maintained despite significant loss of muscle concomitant with weight loss.

Preventable sources of bias in subgroup analyses and secondary outcomes of randomized trials.

BACKGROUND: Randomized controlled trials are the gold standard for determining treatment efficacy in medicine. To deter harmful practices such as p-hacking and hypothesizing after the results are known, any analysis of subgroups and secondary outcomes must be documented and pre-specified. However, they can still introduce bias (and routinely do) if they are not treated with the same consideration as the primary analysis. METHODS: We describe several sources of bias that affect subgroup and secondary outcome analyses using published randomized trials and causal directed acyclic graphs (DAGs). RESULTS: We use the RECOVERY and START trials to elucidate sources of bias in analyses of subgroups and secondary outcomes. Chance imbalance can occur if the distribution of prognostic variables is not sought for any given subgroup analysis as for the main analysis. This differential distribution of prognostic variables can also occur in analyses of secondary outcomes. Selection bias can occur if the subgroup variable is causally related to staying in the trial. Given loss to follow up is not normally addressed in subgroups, attrition bias can pass unnoticed in these cases. In every case, the solution is to take the same considerations for these analyses as we do for primary analyses. CONCLUSIONS: Approval of treatments and clinical decisions can occur based on results from subgroup or secondary outcome analyses. Thus, it is important to give them the same treatment as primary analyses to avoid preventable biases.

The impact of earthquakes in Latin America on the continuity of HIV care: A retrospective observational cohort study.

Objectives: As earthquakes occur frequently in Latin America and can cause significant disruptions in HIV care, we sought to analyze patterns of HIV care for adults at Latin American clinical sites experiencing a significant earthquake within the past two decades. Study design: Retrospective clinical cohort study. Methods: Adults receiving HIV care at sites experiencing at least a "moderate intensity" (Modified Mercalli scale) earthquake in the Caribbean, Central and South America network for HIV epidemiology (CCASAnet) contributed data from 2003 to 2017. Interrupted Time Series models were fit with discontinuities at site-specific earthquake dates (Sept. 16, 2015 in Chile; Apr. 18, 2014 and Sept. 19, 2017 in Mexico; and Aug. 15, 2007 in Peru) to assess clinical visit, CD4 measure, viral load lab, and ART initiation rates 3- and 6-months after versus before earthquakes. Results: Comparing post-to pre-earthquake periods, there was a sharp drop in median visit (incidence rate ratio [IRR] = 0.79, 95% confidence interval [CI]: 0.68-0.91) and viral load lab (IRR = 0.78, 95% CI: 0.62-0.99) rates per week, using a 3-month window. CD4 measurement rates also decreased (IRR = 0.43; 95% CI: 0.37-0.51), though only using a 6-month window. Conclusions: Given that earthquakes occur frequently in Latin America, disaster preparedness plans must be more broadly implemented to avoid disruptions in HIV care and attendant poor outcomes.

Workshop summary: National Institutes of Health (NIH) 2022 scientific workshop on gender and health.

In this manuscript, we summarize the goals, content, and impact of the Gender and Health: Impacts of Structural Sexism, Gender Norms, Relational Power Dynamics, and Gender Inequities workshop held by the National Institutes of Health (NIH) Office of Research on Women's Health (ORWH) in collaboration with 10 NIH Institutes, Centers, and Offices. Specifically, we outline the key points emerging from the workshop presentations, which are the focus of the collection of articles in this supplement. The overarching goals of the workshop were to convene NIH staff, the external scientific community, and the public to discuss methods, measurement, modifiable factors, interventions, and best practices in health research on gender as a social and cultural variable and to identify opportunities to advance research and foster collaborations on these key topics. Themes emerging from the workshop include the need for intersectional measures in research on gender and health, the role of multilevel interventions and analyses, and the importance of considering gender as a social and structural determinant of health. Careful, nuanced, and rigorous integration of gender in health research can contribute to knowledge about and interventions to change the social and structural forces that lead to disparate health outcomes and perpetuate inequities.

Impact of rt-pcr test false-negative results for SARS-CoV-2 surveillance in Mexico

ABSTRACT Background: Underestimation of the number of cases during the coronavirus disease 2019 (COVID-19) pandemic has been a constant concern worldwide. Detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA using real-time reverse-transcription polymerase chain reaction (RT-PCR) is the most common method to confirm a case. However, these tests have suboptimal sensitivity. Objective: The objective of the study was to estimate the number of COVID-19 confirmed cases, intensive care unit (ICU) admissions and deaths in Mexico, accounting for the probabilities of false-negative tests. Methods: We used publicly available, national databases of all SARS-CoV-2 tests performed at public laboratories in Mexico between February 27 and October 31, 2020. We used the estimated probabilities of false-negative tests based on the day of clinical sample collection after symptom initiation calculated previously. With the resulting model, we estimated the corrected daily number of cases, ICU admissions, and deaths. Results: Among 2,024,822 people tested in Mexico between February 27 and October 31 with an available result, we estimated 1,248,583 (95% confidence interval 1,094,850-1,572,818) cases, compared to 902,343 cases reported with positive tests. ICU admissions and deaths were 15% and 8% higher than reported, respectively. Conclusion: Accounting for SARS-CoV-2 RT-PCR-based diagnostic testsҠprecision is a simple way to improve estimations for the true number of COVID-19 cases among tested persons.