Brutto, Óscar H. Del

Abstract Introduction Evidence of the relationship between periodic limb movements during sleep (PLMS) and cerebral small vessel disease (cSVD) is limited and inconsistent. Here, we aimed to assess the independent association between PLMS and the different neuroimaging signatures of cSVD. Methods Community dwelling adults aged ≥60 years enrolled in the Atahualpa Project undergoing PSG and MRI with time intervals ≤6 months were included. MRI readings focused on white matter hyperintensities (WMH) of presumed vascular origin, deep cerebral microbleeds (CMB), silent lacunar infarcts (LI), and >10 enlarged basal ganglia-perivascular spaces (BG-PVS). Data from single-night polysomnograms were interpreted according to recommendations of the American Academy of Sleep Medicine. Associations between the PLMS index and neuroimaging signatures of cSVD (as dependent variables) were assessed by means of logistic regression models, adjusted for relevant confounders. Results A total of 146 individuals (mean age: 71.4 ± 7.5 years; 64% women) were included. A PLMS index ≥15/hour were noted in 48 (33%) participants. Moderate-to-severe WMH were present in 33 individuals (23%), deep CMB in 9 (6%), silent LI in 16 (11%), and >10 BG-PVS in 44 (30%). In univariate analyses, silent LI (p=0.035) and the presence of >10 enlarged BG-PVS (p=0.034) were significantly higher among participants with a PLMS index ≥15/hour. However, fully-adjusted multivariate models showed no significant association between PLMS index ≥15/hour and any of the neuroimaging signatures of cSVD. Conclusion This study shows no independent association between the PLMS index and neuroimaging signatures of cSVD in stroke-free community-dwelling older adults. Support This study was supported by Universidad Espíritu Santo - Ecuador.

Objective Information on the associations among arterial stiffness, carotid intima-media thickness (cIMT) and carotid plaques as biomarkers of atherosclerosis is limited in diverse populations. We aimed to assess whether aortic pulse wave velocity (aPWV) – as a surrogate of arterial stiffness – is associated with increased cIMT and the presence of carotid plaques in a cohort of older adults of Amerindian ancestry. Methods Atahualpa residents aged ≥60 years ( n = 320) underwent aPWV determinations, and carotid ultrasounds for cIMT and plaque assessment. Multivariate models were fitted to assess the independent association between the aPWV, and cIMT and carotid plaques, after adjusting for relevant confounders. Differences in risk factors across these biomarkers were investigated. Results Mean values of aPWV were 10.3 ± 1.8 m/s, and those of cIMT were 0.91 ± 0.21 mm (24% had a cIMT >1 mm). Carotid plaques were observed in 118 (37%) subjects. In univariate analyses, risk factors associated with an increased aPWV included age, female gender, poor physical activity and high blood pressure. An increased cIMT was associated with age, male gender, a poor diet, high blood pressure and severe tooth loss. The presence of carotid plaques was associated with increasing age, poor physical activity and high blood pressure. Multivariate models showed a significant association between aPWV and cIMT (β: 0.028; 95% C.I.: 0.001–0.056; p = 0.047) but not between aPWV and carotid plaques (OR: 1.14; 95% C.I.: 0.83–1.56; p = 0.423). Conclusions This study shows an independent association between aPWV and cIMT but not with carotid plaques. These biomarkers may indicate distinct phenotypes for atherosclerosis.

Background and Purpose— The apnea-hypopnea index (AHI) is associated with cerebral small vessel disease (cSVD), but pathogenesis of this association is elusive. We aimed to assess the effect of nighttime heart rate variability (HRV)—as a proxy of sympathetic upregulation—on the aforementioned association. Methods— Atahualpa residents aged ≥60 years undergoing brain magnetic resonance imaging, polysomnography, and 24-hour Holter monitoring (N=176) were included. The presence of moderate-to-severe white matter hyperintensities, deep cerebral microbleeds, lacunar infarcts, and >10 enlarged basal ganglia perivascular spaces were added for estimating the cSVD score. Interaction models were fitted to assess the effect modification of nighttime HRV in the association between the AHI and the cSVD score, and mediation analysis was utilized to assess the proportion of total effect by nighttime HRV on this association. Results— Generalized linear models showed a significant association between the AHI and the cSVD score ( P =0.025), as well as a significant inverse association between nighttime HRV and the cSVD score ( P =0.002), but no association between daytime HRV and the cSVD score ( P =0.097). Interaction models showed a significant interaction of nighttime HRV on the association between AHI and the cSVD score ( P =0.001), and mediation analysis found that the percent of total effect between AHI and cSVD score mediated by HRV was 30.8%. Predictive marginal means of the cSVD score were highly significant when the 10th percentile of nighttime HRV was compared across categories of 10th and 90th percentiles of the AHI (cSVD score margins, 0.61 [95% CI, 0.37–0.86] versus 1.67 [95% CI, 1.26–2.09]). Contour plots showed the effect of nighttime (but not daytime) HRV on the association between AHI and the cSVD score. Conclusions— This study shows an important effect of nighttime HRV on the association between the AHI and the cSVD score and provides further support for the role of sympathetic overactivity on this association.

There is limited information on participants’ adherence and reasons for declining consent in observational cohort studies conducted in remote rural communities. We aimed at sharing lessons learned during the Atahualpa Project, a population-based cohort study conducted in a rural Ecuadorian village. Atahualpa residents aged ≥40 years identified during door-to-door surveys who signed a consent form were enrolled. Annual surveys were conducted to assess the number of participants who moved out of the village, as well as those who died, declined consent, and newly entered the study. Reasons for declining consent were tabulated. Abstracted data included age, sex, education, disability, time between enrollment and declining consent, and reasons for withdrawal. We also counted participants who, despite expressing their willingness to continue in the study, refused specific procedures. After five years of follow-up, 54 (6.3%) of 863 enrolled individuals declined consent. Increasing age and disability had no impact on declining consent. In contrast, refusal was higher among relatives or neighbors of a given participant declining consent. Most people who declined consent did so after one or two years of enrollment. Less than 20% of enrolled individuals refused certain procedures. “Fear of the needle” was the most frequent reason for refusing blood tests, and common reasons for declining complimentary exams were lack of interest and time constraints. Cohort retention in the Atahualpa Project is high. Main reasons for this adherence include adequate selection of the village, detailed planning of procedures, assurance of sponsorship, and field personnel who continuously engage with study participants. This trial is registered with NCT01627600.

ABSTRACT Background: There is no information on the prevalence of symptoms related to neurotoxicity among carpenters working in underserved populations. To assess the magnitude of the problem, we conducted a population-based study in Atahualpa, a rural Ecuadorian village, where most men work as carpenters under poor safety conditions. Methods: All men aged 40–75 years living in Atahualpa were identified during a door-to-door survey and evaluated with a general demographic questionnaire, the Q16 questionnaire, the depression axis of the Depression Anxiety Stress Scale-21, and the Montreal Cognitive Assessment (MoCA). Results: Among 230 participants, 63% were carpenters. Seventy participants (30%) had a positive Q16 questionnaire (≥6 points), which suggested neurotoxicity. In a logistic regression model adjusted for age, education, alcohol intake, symptoms of depression, and MoCA score, the proportion of Q16 positive persons was 39.1% for carpenters and 15.9% for noncarpenters (odds ratio: 3.53, 95% confidence interval: 1.75–7.15, P < 0.0001). In a generalized linear model, adjusted mean scores in the Q16 questionnaire were 4.9 for carpenters and 3.6 for noncarpenters (β: 1.285, standard error: 0.347, P < 0.0001). There was no correlation between scores in the Q16 questionnaire and the MoCA (Pearson correlation coefficient = −0.02), and the only significant covariate in the multivariate linear model was age, with every 10 years of age difference contributing 0.64 points in the Q16 questionnaire. Conclusion: This study shows a high prevalence of symptoms associated with neurotoxicity among carpenters after adjusting for a number of confounders. Long-term exposure to toxic solvents is the most likely explanation to this finding.

ABSTRACT Community-dwellers aged ≥ 60 years enrolled in the Atahualpa Project underwent brain MRI and were interviewed with the Pittsburgh Sleep Quality Index. Of 290 participants, 94 (32%) had poor sleep quality and 143 (49%) had global cortical atrophy (GCA). In a logistic regression model (adjusted for demographics, cardiovascular risk factor, severe edentulism, symptoms of depression, the MoCA score, and neuroimaging signatures of cerebrovascular damage), poor sleep quality was associated with GCA (p=0.004). A multivariate probability model showed that the probability of moderate-to-severe GCA significantly increased in individuals with poor sleep quality aged ≥ 67 years. This study provides evidence for an association between poor sleep quality and GCA in older adults and the important interaction of age in this association.

The effect of fish consumption on blood pressure is controversial. The authors measured blood pressure and calculated oily fish servings per week in 677 community‐dwellers aged 40 years and older living in rural coastal Ecuador. Using regression models with linear splines, the authors evaluated whether dietary fish intake was related to blood pressure levels, after adjusting for relevant confounders. Mean oily fish consumption was 9.1±5.6 servings per week. There was a nonlinear relationship between systolic pressure and fish servings. In the group of individuals consuming up to five servings per week, each serving significantly reduced systolic pressure by 2.3 mm Hg (P=.020). Any extra serving provided no further effects. The study shows an inverse relationship between oily fish consumption and systolic pressure. Currently recommended amounts of dietary oily fish intake per week (1–2 servings) might be insufficient to exert beneficial effects of fish in the control of blood pressure.

ABSTRACTPurposeTo assess the role of temporal bone characteristics in transcranial Doppler (TCD) insonation failures in Amerindians living in rural Ecuador.MethodsWe evaluated thickness and texture of temporal bones in community‐dwelling Amerindians ≥65 years old undergoing TCD. Using receiver operator characteristics curve analysis and generalized estimating equations, we investigated factors associated with insonation failures.ResultsOf 65 participants (mean age 74.7 ± 6.7 years, 60% women), 32 (49%) had uni‐ or bilateral insonation failure through temporal windows. Considering temporal bones independently, 57 of 130 (44%) had poor insonation. Mean thickness was higher (4.7 ± 1.2 versus 2.7 ± 0.9, p < 0.0001), and texture more often heterogeneous (93% versus 22%, p < 0.0001) in bones with poor acoustic windows. Thickness, better predicting poor insonation, was ≥3.6 mm if used alone, and ≥2.7 mm if used together with heterogeneous texture. For every millimeter of increase in thickness, subjects were 2.9 times more likely to have insonation failures. Per se, heterogeneous texture increased by 3.2 times the odds for poor insonation. In all models, being woman increased the odds for poor insonation by six to nine times.ConclusionsTemporal bone thickness and texture are independent predictors of TCD insonation failure in Amerindians. © 2015 Wiley Periodicals, Inc. J Clin Ultrasound 44:55–60, 2016