Death Risk Response of High-Altitude Resident Populations to COVID-19 Vaccine: A Retrospective Cohort Study.

Vásquez-Velásquez, Cinthya, Diego Fano-Sizgorich, and Gustavo F Gonzales. Death risk response of high-altitude resident populations to COVID-19 vaccine: Retrospective cohort study. High Alt Med Biol. 00:00-00, 2024. Background: Peru had one of the highest mortality rates caused by the coronavirus disease 2019 (COVID-19) pandemic worldwide. Vaccination significantly reduces mortality. However, the effectiveness of vaccination might differ at different altitudinal levels. The study aimed to evaluate the effect modification of altitude on the association between vaccination and COVID-19 mortality in Peru. Methodology: A retrospective cohort, using open access databases of deaths, COVID-19 cases, hospitalizations, and vaccination was obtained from the Peruvian Ministry of Health. Deaths due to COVID-19 were evaluated in vaccinated and nonvaccinated patients. Crude (RR) and adjusted relative risks (aRR) were calculated using generalized linear models of Poisson family with robust variances. Models were adjusted for age, sex, pandemic wave, and Human Development Index. To evaluate the interaction by altitude, a stratified analysis by this variable was performed. The variable altitude was categorized as, 0-499 m (828,298 cases), 500-1,499 m (64,735 cases), 1,500-2,499 m (106,572 cases), and ≥2,500 m (179,004 cases). The final sample studied included 1,362,350 cases. Results: The vaccine showed a considerable reduction of death risk with the second (aRR: 0.41, 95% confidence interval [CI]: 0.38-0.44) and third doses (aRR: 0.21, 95% CI: 0.20-0.23). In the adjusted and interaction model, it can be observed that medium and high altitude present a higher risk of death compared to sea level (aRR: 2.58 and 2.03, respectively). Likewise, the two doses' group presents an aRR:1.22 for medium altitude (1,500-2,499 m) and 1.6 for high altitude (≥2,500 m), compared with low-altitude population, suggesting that the action of vaccination at high altitude is altered by the effect of the altitude itself. Conclusions: Altitude might modify the protective effect of SARS-CoV-2 vaccine against COVID-19 death.

Risk of death, hospitalization and intensive care unit admission by SARS-CoV-2 variants in Peru: a retrospective study.

OBJECTIVES: Peru has had the highest death toll from the pandemic worldwide; however, it is not clear what the effects of the different variants on these outcomes are. The study aimed to evaluate the risk of death, hospitalization, and intensive care unit (ICU) admission rates of COVID-19 according to the SARS-CoV-2 variants detected in Peru from March 2020-February 2022. METHODS: Retrospective study using open-access databases were published by the Peruvian Ministry of Health. Databases of genomic sequencing, death, COVID-19 cases, hospitalization and ICU, and vaccination were used. Crude and adjusted Cox proportional hazards regressions with clustered variances were modeled to calculate the hazard ratio (HR) of outcomes by variant. RESULTS: Lambda variant had the highest risk of death (HR 1.92, 95% CI 1.37-2.68), whereas the Delta variant had the lowest risk (HR 0.50, 95% CI 0.31-0.82). Mu variant had the highest risk of hospitalization (HR: 2.39, 95% CI 1.56-3.67), Omicron the lowest (HR 0.45, 95%CI 0.23-0.90), and Gamma had the highest ICU admission rate (HR 1.95, 95%CI 1.40-2.71). CONCLUSION: SARS-CoV-2 variants showed distinctive risks of clinical outcomes, which could have implications for the management of infected persons during the pandemic.

Comparison of two isothermal methods for SARS-COV-2 screening in Callao, Peru

Objective: To compare the isothermal molecular screening techniques CPA and RT-LAMP, against the gold standard test, reverse transcription quantitative polymerase chain reaction (RT-qPCR), and to determine its agreement. Materials and Methods: Paired comparative case-control study. For the evaluation of the CPA method, 70 cases and 130 controls were used, while for RT-LAMP, 30 cases and 70 controls were used. The sensitivity and specificity of both tests were calculated. Subsequently, the bias-corrected Kappa index was calculated by resampling. Results: Both techniques have adequate and equivalent values of sensitivity (RT-LAMP: 82.8%, CPA: 83%) and specificity (RT-LAMP and CPA: 91.5%), as well as a high concordance (88%), and Kappa-index (0.72). Conclusion: Both isothermal molecular screening techniques are suitable for SARS-CoV-2 screening, with a similar sensitivity and specificity.

Objetivo : Comparar las técnicas de cribado molecular isotérmico CPA y RT-LAMP, frente a la prueba de referencia, la reacción en cadena de la polimerasa cuantitativa de transcripción inversa (RT-qPCR), y determinar su concordancia. Materiales y métodos : Estudio comparativo de casos y controles emparejados. Para la evaluación del método CPA se utilizaron 70 casos y 130 controles, mientras que para la RT-LAMP se utilizaron 30 casos y 70 controles. Se calcularon la sensibilidad y la especificidad de ambas pruebas. Posteriormente, se calculó el índice Kappa corregido por sesgo mediante un nuevo muestreo. Resultados: Ambas técnicas presentan valores adecuados y equivalentes de sensibilidad (RT-LAMP: 82,8 %, CPA: 83 %) y especificidad (RT-LAMP y CPA: 91,5 %), así como una alta concordancia (88 %), y un índice Kappa (0,72). Conclusiones: Ambas técnicas de cribado molecular isotérmico son adecuadas para el cribado del SARS-CoV-2, con una sensibilidad y especificidad similares.

Total Urinary Arsenic and Inorganic Arsenic Concentrations and Birth Outcomes in Pregnant Women of Tacna, Peru: A Cross-Sectional Study.

Inorganic arsenic exposure has been linked to the development of several health conditions, including adverse birth outcomes; and around 150 million of people worldwide are exposed to levels above the WHO suggested limit of 10 µg/L. A recent risk assessment in pregnant women of Tacna, of this same population performed by our group, found that 70.25% were exposed to arsenic concentrations in drinking water ≥25 µg/L. The present study aimed to evaluate the relationship between prenatal total urinary arsenic (U-tAs) and inorganic arsenic (U-iAs) with adverse birth outcomes. A total of 147 pregnant women from the province of Tacna, Peru, during February - March, 2019, were evaluated for U-tAs and U-iAs exposure during their second trimester of pregnancy, while the birth records of their children were collected from the local hospital. The geometric mean U-tAs was 43.97 ± 25.88 µg/L (P50 22.30, range 5.99 - 181.94 µg/L) and U-iAs was 5.27 ± 2.91 µg/L. Controlling for maternal age, pre-pregnancy BMI, parity, mother's education and newborn sex, no relationship was observed between tertile of U-tAs and the birth outcomes considered, although we found an apparent but statistically non-significant dose-response relationship for small-for-gestational-age 2.38% ( 95% CI 0.003, 0.16), versus 7.32% (95% CI 0.02, 0.21%), versus 8.57% (0.03, 0.25%). This finding requires further evaluation considering other factors such as metabolic arsenic species, additional maternal covariates and ethnicity.

Inflammatory pathway employed by Red Maca to treat induced benign prostatic hyperplasia in rats.

Benign prostatic hyperplasia (BPH) is a pathology characterised by an increase in prostate size associated with low urinary tract symptoms. Finasteride (F), a 5a-reductase inhibitor, is the standard treatment for BPH reducing prostate weight but also sexual desire. The Peruvian plant known as Red Maca (RM) (Lepidium meyenii) inhibits BPH in rats and mice. The aim of the study was to assess the inflammatory effect of RM and finasteride in rats with testosterone enanthate (TE)-induced BPH. Thirty rats were divided into 5 groups: Control, TE (50 mg/rat), TE + F (0.6 mg/kg), and two groups of TE + RM 40/80 (40 or 80 mg). After treatments, tumour necrosis factor alpha (TNFa), interleukin 4 (IL4) and interferon gamma (INFg) as well as testosterone and oestradiol were evaluated and inflammatory cells (neutrophils, mast cells and lymphocytes) in prostate were quantified. Red Maca and finasteride treatments decreased inflammatory cells counts in prostate, inhibiting TNFa by different pathways. Finasteride increased IL4 whereas Red Maca increased INFg. In conclusion, data suggest that finasteride acts on Th2 response by increasing IL4 in prostate, while Red Maca acts on Th1 response mediated by INFg.