Research on aging during the Venezuelan humanitarian crisis: the experience of the Maracaibo aging study.

BACKGROUND: Venezuela is in the throes of a complex humanitarian crisis that is one of the worst in decades to impact any country outside of wartime. This case analysis describes the challenges faced by the ongoing Maracaibo Aging Study (MAS) during the deteriorating conditions in Venezuela. When the MAS began in 1997, it focused on memory-related disorders. Since then, strategic planning and proactive community participation allowed us to anticipate and address logistical, funding, and ethical challenges, and facilitated the enrollment and retention of more than 2500 subjects over 55 years of age. All participants, who are residents of the city of Maracaibo, Venezuela, underwent various assessments on several occasions. Here, we discuss how our approach to implementing a longitudinal, population-based study of age-related conditions has allowed our research program to continue throughout this period of political, economic, and social upheaval. DISCUSSION: As the social context in Venezuela became more complicated, new challenges emerged, and strategies to sustain the study and participation were refined. We identified five main mechanisms through which the evolving humanitarian crisis has affected implementation of the MAS: 1) community dynamics; 2) morale of researchers, staff, and participants; 3) financial feasibility; 4) components of the research process; and 5) impact on the health of staff, participants, and their families. Strategies to compensate for the impact on these components were implemented, based on inputs from community members and staff. Improved communication, greater involvement of stakeholders, broadening the scope of the project, and strengthening international collaboration have been the most useful strategies. Particular demands emerged, related to the increased mortality and comorbidities of participants and staff, and deterioration of basic services and safety. CONCLUSION: Although the MAS has faced numerous obstacles, it has been possible to continue a longitudinal research project throughout the humanitarian crisis, because our research team has engaged the community deeply and developed a sense of mutual commitment, and also because our project has provided funding to help keep researchers employed, somewhat attenuating the brain drain.

Subclinical Magnetic Resonance Imaging Markers of Cerebral Small Vessel Disease in Relation to Office and Ambulatory Blood Pressure Measurements.

Background: Twenty-four-hour and nighttime blood pressure (BP) levels are more strongly associated with cardiovascular risk than office or daytime BP measurements. However, it remains undocumented which of the office and ambulatory BP measurements have the strongest association and predictive information in relation to the presence of type I, or arteriolosclerosis type, cerebral small vessel diseases (CSVD). Methods: A subset of 429 participants from the Maracaibo Aging Study [aged ≥40 years (women, 73.7%; mean age, 59.3 years)] underwent baseline brain magnetic resonance imaging (MRI) to visualize CSVD, which included log-transformed white matter hyperintensities (log-WMH) volume and the presence (yes/no) of lacunes, cerebral microbleeds (CMB), or enlarged perivascular spaces (EPVS). Linear and logistic regression models were applied to examine the association between CSVD and each +10-mmHg increment in the office and ambulatory systolic BP measurements. Improvement in the fit of nested logistic models was assessed by the log-likelihood ratio and the generalized R 2 statistic. Results: Office and ambulatory systolic BP measurements were related to log-WMH (ß-correlation coefficients ≥0.08; P < 0.001). Lacunes and CMB were only associated with ambulatory systolic BP measurements (odds ratios [OR] ranged from 1.31 [95% confidence interval, 1.10-1.55] to 1.46 [1.17-1.84], P ≤ 0.003). Accounted for daytime systolic BP, both the 24-h (ß-correlation, 0.170) and nighttime (ß-correlation, 0.038) systolic BP measurements remained related to log-WMH. When accounted for 24-h or daytime systolic BP levels, the nighttime systolic BP retained the significant association with lacunes (ORs, 1.05-1.06; 95% CIs, ≥1.01 to ≤ 1.13), whereas the 24-h and daytime systolic BP levels were not associated with lacunes after adjustments for nighttime systolic BP (ORs, ≤ 0.88; 95% CI, ≥0.77 to ≤ 1.14). On top of covariables and office systolic BP, ambulatory systolic BP measurements significantly improved model performance (1.05% ≥ R 2 ≤ 3.82%). Compared to 24-h and daytime systolic BP, nighttime systolic BP had the strongest improvement in the model performance; for WMH (1.46 vs. 1.05%) and lacunes (3.06 vs. ≤ 2.05%). Conclusions: Twenty-four-hour and nighttime systolic BP were the more robust BP measurements associated with CSVD, but the nighttime systolic BP level had the strongest association. Controlling ambulatory BP levels might provide additional improvement in the prevention of CSVD.

White matter hyperintensities mediate the association of nocturnal blood pressure with cognition.

OBJECTIVE: To test the hypotheses that hypertension and nocturnal blood pressure are related to white matter hyperintensity (WMH) volume, an MRI marker of small vessel cerebrovascular disease, and that WMH burden statistically mediates the association of hypertension and dipping status with memory functioning, we examined the relationship of hypertension and dipping status on WMH volume and neuropsychological test scores in middle-aged and older adults. METHODS: Participants from the community-based Maracaibo Aging Study received ambulatory 24-hour blood pressure monitoring, structural MRI, and neuropsychological assessment. Four hundred thirty-five participants (mean ± SD age 59 ± 13 years, 71% women) with available ambulatory blood pressure, MRI, and neuropsychological data were included in the analyses. Ambulatory blood pressure was used to define hypertension and dipping status (i.e., dipper, nondipper, and reverse dipper based on night/day blood pressure ratio <0.9, 0.9-1, and >1, respectively). Outcome measures included regional WMH and memory functioning derived from a neuropsychological test battery. RESULTS: The majority of the participants (59%) were hypertensive. Ten percent were reverse dippers, and 40% were nondippers. Reverse dipping in the presence of hypertension was associated with particularly elevated periventricular WMH volume (F 2,423 = 3.78, p = 0.024) and with lowered memory scores (F 2,423 = 3.911, p = 0.021). Periventricular WMH volume mediated the effect of dipping status and hypertension on memory (ß = -4.1, 95% confidence interval -8.7 to -0.2, p < 0.05). CONCLUSION: Reverse dipping in the presence of hypertension is associated with small vessel cerebrovascular disease, which, in turn, mediates memory functioning. These results point toward reverse dipping as a marker of poor nocturnal blood pressure control, particularly among hypertensive individuals, with potentially pernicious effects on cerebrovascular health and associated cognitive function.

Reconocimiento visual de cadáveres calcinados posterior a la aplicación de dos técnicas de autopsia bucal: un estudio comparativo / Visual identification of calcinated cadavers, following the application of two techniques of oral autopsy: a comparative study

La evidencia dental es determinante en la identificación de cadáveres provenientes de desastres masivos, especialmente cuando éstos involucran la exposición directa al fuego. Si en estos cadáveres son aplicadas las técnicas convencionales de autopsia bucal, se produce la pérdida de la configuración facial, dificultándose el reconocimiento visual por parte de familiares, el cual es importante especialmente cuando los registros dentales antemortem no están disponibles. Se examinaron 166 cadáveres carbonizados o con quemaduras de tercer a cuarto grado, no identificados, los cuales fueron ubicados en dos grupos: grupo 1, con 49 cadáveres a los que se les aplicó el protocolo de autopsia bucal que se sigue de rutina en la Medicatura Forense de la Ciudad de Maracaibo, y grupo 2, con 117 cadáveres examinados según el protocolo de autopsia bucal para cadáveres calcinados, propuesto por Ferreira y cols. (1997). En el grupo 2, se obtuvo como resultado un mayor porcentaje de identificaciones logradas mediante evidencia no dental, gracias a la naturaleza conservadora de la técnica aplicada

La experticia odontológica en el proceso penal / Dental capability in the penal process

El odontólogo forense juega un papel fundamental como testigo experto antes los juzgados civiles cuando se considera la evidencia dental. Se reporta un caso donde el cadáver de una mujer de 28 años fue sepultado en mayo de 1990, víctima aparente de un arrollamiento por vehículo automotor. La necropsia reveló fracturas complejas con deformidad de los huesos de cráneo y cara, producidas por objeto contundente. Posteriormente, la madre de la occisa consignó ante las autoridades una pieza dental y un fragmento de esmalte dentario, que habían sido encontrados en un sitio diferente al descrito como lugar del accidente. Este hallazgo, aunado a otras experticias policiales, planteó la posibilidad de que se estuviera en presencia de un homicidio, siendo el esposo de la víctima el principal sospechoso. Iniciadas las investigaciones, se ordenó la exhumación. Durante la autopsia bucal, pudo comprobarse que la evidencia dental aportada correspondía a la dentadura de la occisa, complementando así la investigación policial que condujo al esclerecimiento de un crimen, a la identificación del autor material y al dictado de una sentencia firme. Constituyéndose de esta manera, la experticia odontológica en un factor determinante en el proceso penal