Background and purpose Neurological complications of SARS‐CoV‐2 infection are noticed among critically ill patients soon after disease onset. Information on delayed neurological sequelae of SARS‐CoV‐2 infection is nil. Following a longitudinal study design, the occurrence of cognitive decline among individuals with a history of mild symptomatic SARS‐CoV‐2 infection was assessed. Methods Stroke‐ and seizure‐free Atahualpa residents aged ≥40 years, who had pre‐pandemic cognitive assessments as well as normal brain magnetic resonance imaging and electroencephalogram recordings, underwent repeated evaluations 6 months after a SARS‐CoV‐2 outbreak infection in Atahualpa. Patients requiring oxygen therapy, hospitalization, and those who had initial neurological manifestations were excluded. Cognitive decline was defined as a reduction in the Montreal Cognitive Assessment (MoCA) score between the post‐pandemic and pre‐pandemic assessments that was ≥4 points greater than the reduction observed between two pre‐pandemic MoCAs. The relationship between SARS‐CoV‐2 infection and cognitive decline was assessed by fitting logistic mixed models for longitudinal data as well as exposure‐effect models. Results Of 93 included individuals (mean age 62.6 ± 11 years), 52 (56%) had a history of mild symptomatic SARS‐CoV‐2 infection. Post‐pandemic MoCA decay was worse in seropositive individuals. Cognitive decline was recognized in 11/52 (21%) seropositive and 1/41 (2%) seronegative individuals. In multivariate analyses, the odds for developing cognitive decline were 18.1 times higher among SARS‐CoV‐2 seropositive individuals (95% confidence interval 1.75–188; p = 0.015). Exposure‐effect models confirmed this association ( β = 0.24; 95% confidence interval 0.07–0.41; p = 0.006). Conclusions This study provides evidence of cognitive decline among individuals with mild symptomatic SARS‐CoV‐2 infection. The pathogenesis of this complication remains unknown.

Antibodies to SARS-CoV-2 were detected in 303/673 rural Ecuadorian adults (45%), 77% of whom had compatible clinical manifestations. Seropositivity was associated with the use of open latrines. Our findings support the fears of mass spread of SARS-CoV-2 in rural Latin America and cannot exclude a contributing role for fecal-oral transmission.

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Data on SARS-CoV-2 transmission in rural communities is scarce or non-existent. A previous cross-sectional study in middle-aged and older adults enrolled in the Atahualpa Project Cohort demonstrated that 45% of participants had SARS-CoV-2 antibodies, 77% of whom were symptomatic. Here, we assessed the incidence of SARS-CoV-2 infection in the abovementioned rural population. One month after baseline testing, 362 of 370 initially seronegative individuals were re-tested to assess incidence of seroconversion and associated risk factors. Twenty-eight of them (7.7%) became seropositive. The overall incidence rate ratio was 7.4 per 100 person months of potential virus exposure (95% C.I.: 4.7-10.2). Six seroconverted individuals (21.4%) developed SARS-CoV-2-related symptomatology. The only covariate significantly associated with seroconversion was the use of an open latrine. Predictive margins showed that these individuals were 2.5 times more likely to be infected (95% C.I.: 1.03-6.1) than those using a flushing toilet. Therefore, along one month, approximately 8% of seronegative individuals became infected, even after almost half of the population was already seropositive. Nevertheless, a smaller proportion of incident cases were symptomatic (21% versus 77% of the earlier cases), and no deaths were recorded. Whether this decreased clinical expression resulted from a lower viral load in new infections cannot be determined. Increased seroconversion in individuals using latrines is consistent with a contributory role of fecal-oral transmission, although we cannot rule out the possibility that latrines are acting as a proxy for poverty or other unknown interacting variables.

High social risk, as measured by the social determinants of health (SDH), may increase the risk of SARS-CoV-2 infection. However, this association has not been studied in rural communities. Using the Atahualpa Project cohort, we aimed to assess the association between SDH and SARS-CoV-2 seropositivity in community-dwelling older adults living in rural Ecuador. SARS-CoV-2 antibodies were determined in 319 individuals aged ≥ 60 years that completed a validated field instrument to assess their social risk before the introduction of this novel pandemic. Multivariate models were fitted to assess the independent association between SDH—and each of their components—and SARS-CoV-2 seropositivity, after adjusting for relevant covariates. According to the Gijon scale, 102 (32%) individuals had a high social risk (≥ 10 points). A total of 141 (44%) individuals were seropositive to SARS-CoV-2. A fully-adjusted logistic regression model showed an independent) association between social risk and SARS-CoV-2 positivity (OR 1.15; 95% CI 1.04–1.27; p = 0.008). For every unit of the total SDH score, the odds of SARS-CoV-2 seropositivity increased 15% (95% CI 3.7–27%). In addition, multivariate models showed that the individual component of SDH more strongly associated with SARS-CoV-2 seropositivity was housing, which suggested that lack of basic home facilities may increase the risk of SARS-CoV-2 infection. Knowledge on the association between high social risk and SARS-CoV-2 infection is indispensable for the development of cost-effective preventive strategies for controlling modifiable factors that are in the path of SARS-CoV-2 infection among older adults living in underserved communities.

Highlights There is no evidence on mortality rates of SARS-CoV-2 in remote rural settings. We calculated SARS-CoV-2 mortality rate of adults living in Atahualpa (rural Ecuador). SARS-CoV-2 mortality rate was 15.7/1,000, which increased to 68.9/1,000 when only older adults were considered. Most deaths occurred over a two-month period, and markedly decreased subsequently.

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.

Objective: To assess the association between SARS-CoV-2 infection and decreased hand grip strength (HGS).Design: Longitudinal population-based study. Setting: Community-dwelling older adults (aged ≥60 years) living in a rural Ecuadorian village struck by the SARS-CoV-2 pandemic. Participants: Of 282 enrolled individuals, 254 (90%) finished the study.Measurements: HGS was measured 3 months before (January 2020) and 9 months after the introduction of the virus into the population (January 2021). SARS-CoV-2 antibody testing was performed in two rounds: in May-June (early) and September-November (late), 2020. An independent association between SARS-CoV-2 infection and HGS decline was assessed by fitting linear mixed models for longitudinal data. Changes in HGS scores in SARS-CoV-2 seropositive subjects, according to the time elapsed since seroconversion, were compared with those who remained seronegative.Results: Overall, 149 (59%) individuals became seropositive for SARS-CoV-2. The mean HGS (in kg) was 25.3 ± 8.3 at baseline and 23.7 ± 8.1 at follow-up (p = 0.028), with 140 individuals having >5% HGS decline between both measurements. The follow-up HGS measurement decreased by 1.72 kg in seropositive individuals, and by 0.57 kg in their seronegative counterparts (p < 0.001). SARS-CoV-2 seropositive individuals were 2.27 times more likely (95% CI: 1.33-3.87) to have a lower HGS measurement at the time of follow-up than those who remained seronegative. When compared with seronegative subjects, seropositive patients with early seroconversion were 3.41 times (95% CI: 1.73-6.74) more likely to have >5% HGS decline at the time of the follow-up than those with later, i.e., more recent, infections. Conclusions: This study shows an independent deleterious impact of SARS-CoV-2 on HGS that is more marked among individuals with infections that occurred more than 8 months before follow-up HGS. Results suggest the possibility of chronic damage to skeletal muscles by SARS-CoV-2.