Sleep quality does not mediate the negative effects of chronodisruption on body composition and metabolic syndrome in healthcare workers in Ecuador.

BACKGROUND AND AIMS: The objective of the present work was to determine to what extent sleep quality may mediate the association between chronodisruption (CD) and metabolic syndrome (MS), and between CD and body composition (BC). METHODOLOGY: Cross-sectional study which included 300 adult health workers, 150 of whom were night shift workers and thereby exposed to CD. Diagnosis of MS was made based on Adult Treatment Panel III criteria. Sleep quality was measured using the Pittsburgh Sleep Quality Index. Body mass index (BMI), fat mass percentage, and visceral fat percentage were measured as indicators of body composition (BC). Data were analyzed using logistic, linear regression and structural equation models. RESULTS: The odds of health workers exposed to CD to suffer MS was 22.13 (IC95 8.68-66.07) when the model was adjusted for age, gender, physical activity and energy consumption. CD was also significantly associated with an increase in fat mass and visceral fat percentages, but not to BMI. Surprisingly, there was not enough evidence supporting the hypothesis that sleep quality contributes to the association between CD and MS or between CD and BC. CONCLUSIONS: Sleep quality does not mediate the negative effects of CD on MS nor on BC.

Blood Pressure in Andean Adults Living Permanently at Different Altitudes.

Vinueza Veloz, Andrés Fernando, Aymaru Kailli Yaulema Riss, Chris I. De Zeeuw, Tannia Valeria Carpio Arias, and María Fernanda Vinueza Veloz. Blood pressure in Andean adults living permanently at different altitudes. High Alt Med Biol. 21:360-369, 2020. Aims: To estimate the association between blood pressure (BP) and chronic exposure to altitude in nonhypertensive Andean adults, while taking ethnicity into consideration. Materials and Methods: Sample included 10,041 nonhypertensive adults with indigenous or mixed ethnic background (the latter also referred to as mestizos), who permanently lived at different altitudes. BP was measured following international recommendations. Altitude was measured in meters above the sea level (masl) using a global positioning system. Data were analyzed through linear regression models with restricted cubic splines. Results: A significant nonlinear relation between altitude and systolic blood pressure (SBP) as well as diastolic blood pressure (DBP) was found (both p < 0.001). BP described a j-shaped curve, where the minimum was observed between 750 and 1250 masl, from where both SBP and DBP rose as altitude increased. These associations were independent from sex, age, index of economic wellbeing, body mass index, and years of education. Interestingly, at all altitudes indigenous people had lower SBP and DBP in comparison to mestizos (both p < 0.001). Conclusions: Living permanently at altitudes ≥750 masl is associated with higher SBP and DBP in Andean dwellers and this association is modulated by their ethnic background.

Genetic risk for Alzheimer disease in children: Evidence from early-life IQ and brain white-matter microstructure.

It remains unclear whether the genetic risk for late-onset Alzheimer disease (AD) is linked to premorbid individual differences in general cognitive ability and brain structure. The objective of the present study was to determine whether the genetic risk of late-onset AD is related to premorbid individual differences in intelligence quotient (IQ) and characteristics of the cerebral white-matter in children. The study sample included children of the Generation R Study from Rotterdam, The Netherlands. IQ was measured using a well-validated Dutch nonverbal IQ test (n = 1908) at ages 5 to 9 years. White-matter microstructure was assessed by measuring fractional anisotropy (FA) of white-matter tracts using diffusion tensor imaging (DTI) (n = 919) at ages 9 to 12 years. Genetic risk was quantified using three biologically defined genetic risk scores (GRSs) hypothesized to be related to the pathophysiology of late-onset AD: immune response, cholesterol/lipid metabolism and endocytosis. Higher genetic risk for late-onset AD that included genes associated with immune responsivity had a negative influence on cognition and cerebral white-matter microstructure. For each unit increase in the immune response GRS, IQ decreased by 0.259 SD (95% CI [-0.500, -0.017]). For each unit increase in the immune response GRS, global FA decreased by 0.373 SD (95% CI [-0.721, -0.026]). Neither cholesterol/lipid metabolism nor endocytosis GRSs were associated with IQ or cerebral white-matter microstructure. Our findings suggest that elevated genetic risk for late-onset AD may in part be manifest during childhood neurodevelopment through alterations in immune responsivity.