Dietary Oily Fish Intake and Blood Pressure Levels: A Population-Based Study

Oily fish reduces the risk of acne by lowering fasting insulin levels: A Mendelian randomization study

Meat intake, particularly from oily fish, has been associated with various chronic diseases. However, its relationship with acne has always been controversial. Therefore, we have adopted Mendelian randomization (MR) analysis to investigate the causal relationship between different types of meat intake and acne. The exposure and outcome datasets for this study were obtained from the Integrative Epidemiology Unit (IEU) Open GWAS project. Seven datasets on meat intake were included, which consisted of non-oily fish, oily fish, lamb/mutton, poultry, pork, beef, and processed meat. The main methods used for MR analysis were inverse variance weighted, weighted median, and MR-egger. To ensure the accuracy of the results, heterogeneity, pleiotropy, and Mendelian randomization pleiotropy residual sum and outlier (MR-PRESSO) analyses were conducted. Additionally, an analysis of four risk factors (fasting insulin, insulin resistance, total testosterone level, and estradiol level) was performed to investigate the underlying mechanisms linking statistically significant meat intake to acne. Oily fish intake was found to be a protective factor for acne (OR: 0.22, 95% CI: 0.10-0.49, p < .001), and it was also observed that oily fish intake can reduce the level of fasting insulin by the IVW method (OR: 0.89, 95% CI: 0.81-0.98, p = .02). No causal relationship was identified between other types of meat intake and acne. The intake of oily fish reduces the risk of acne by lowering fasting insulin levels.

On the association between dietary oily fish intake and bone mineral density in frequent fish consumers of Amerindian ancestry. The three villages study

Reports addressing the effects of oily fish intake on bone health are inconsistent. This study shows that consumption of ≥ 5.2 oily fish servings/week (728 g) is associated with lower prevalence of osteopenia/osteoporosis in elderly women of Amerindian ancestry. Results suggest a beneficial effect of oily fish intake in this population.

OBJECTIVES

Oily fish is a major dietary source of omega-3 polyunsaturated fatty acids and other nutrients that may have a positive effect on bone health. However, this association is inconsistent and seems to be more evident in certain ethnic groups. We aimed to assess the association between oily fish intake and bone mineral density (BMD) in frequent fish consumers of Amerindian ancestry living in rural Ecuador.

METHODS

This study included 399 individuals aged ≥ 60 years living in three neighboring rural villages of coastal Ecuador. Dietary oily fish intake was quantified systematically using validated surveys and BMD was determined by dual-energy x-ray absorptiometry. Ordinal logistic regression models, adjusted for demographics and cardiovascular risk factors, were fitted to assess the independent association between oily fish intake and bone health.

RESULTS

Participants had a mean age of 68.8 ± 6.8 years, and 58% were women. The mean intake of oily fish was 8.5 ± 4.7 servings/week, with 308 (77%) reporting high fish intake (≥ 5.2 servings/week [728 g]). Ninety-four (24%) participants had normal BMD T-scores, 149 (37%) had osteopenia, and 156 (39%) had osteoporosis. Ordinal logistic regression models showed no association between high fish intake and bone health in the total population. When men and women were analyzed separately, the association became significant for women only in both unadjusted (OR: 2.52; 95% C.I.: 1.22 - 5.23) and fully-adjusted models (OR: 2.23; 95% C.I.: 1.03 - 4.81).

CONCLUSION

Consumption of ≥ 5.2 oily fish servings/week is associated with lower prevalence of osteopenia and osteoporosis in elderly women of Amerindian ancestry.

Dietary oily fish intake reduces the risk of all-cause mortality in frequent fish consumers of Amerindian ancestry living in coastal Ecuador: the Atahualpa project

PURPOSE

To assess the relationship between dietary oily fish intake and all-cause mortality in a population of frequent fish consumers of Amerindian ancestry living in rural Ecuador.

METHODS

Individuals aged ≥ 40 years enrolled in the prospective population-based Atahualpa Project cohort received annual questionnaires to estimate their dietary oily fish intake. Only fish served broiled or cooked in the soup were included for analysis. Poisson regression and Cox-proportional hazards models adjusted for demographics, education level and cardiovascular risk factors were obtained to estimate mortality risk according to the amount of oily fish intake stratified in tertiles.

RESULTS

Analysis included 909 individuals (mean age: 55.1 ± 12.8 years) followed by a median of 7.5 ± 3 years. Mean oily fish intake was 9.4 ± 5.7 servings per week. A total of 142 (16%) individuals died during the follow-up. The mortality rate for individuals in the first tertile de oily fish intake (0.0-6.29 servings) was 2.87 per 100 person-years, which decreased to 1.78 for those in the third tertile (10.59-35.0 servings). An adjusted Cox-proportional hazards model showed that individuals allocated to the second (HR 0.61; 95% CI 0.41-0.92) and third (HR 0.60; 95% CI 0.40-0.91) tertiles of dietary oily fish intake had significantly lower mortality risk than those in the first tertile.

CONCLUSION

Sustained oily fish intake of more than six servings per week reduces mortality risk in middle-aged and older adults of Amerindian ancestry.

The Interplay between Cardiovascular Risk, Cardiovascular Events, and Disease Activity in Primary Sjögren's Syndrome: Is Uric Acid the Missing Link?

(1) Background: Uric acid is a well-known cardiovascular (CV) risk factor in the general population but its role in the setting of rheumatic diseases other than gout is unclear. (2) Methods: This is a retrospective study investigating a cohort of 105 pSS patients recording clinical, serological, and CV-related variables including adherence to the Mediterranean diet. (3) Results: We observed a strong relationship between disease activity, interstitial lung disease (ILD), and CV events. The association between ILD and CV events was dependent on higher SUA levels but independent of other traditional CV risk factors. All three cases of previous non-fatal stroke were reported by females aged <65 years, with higher SUA levels, and two of them also had pSS-ILD. Forty (38%) patients had a 10-year risk of fatal and non-fatal CV disease events beyond the cut-off recommended for their age, and using the correction factor of 1.5 currently applied only to rheumatoid arthritis, we could better identify patient subsets characterized by different CV risk profiles including different SUA levels. (4) Conclusions: This study is the first to investigate in depth the role of SUA in the CV scenario of pSS. Our findings underpin the importance of assessing SUA levels in pSS in addition to the other traditional CV risk factors and to consider applying the correction factor for CV risk assessment tools to achieve a better stratification of CV risk.

Fish consumption in multiple health outcomes: an umbrella review of meta-analyses of observational and clinical studies

Background

Omega-3 polyunsaturated fatty acids are known to be associated with numbers of health benefits, and which can be uptake from fish. The aim of this study was to evaluate the current evidence of associations between consumption of fish and diverse health outcomes. Here, we performed an umbrella review to summarize the breadth, strength, and validity of the evidence derived from meta-analyses and systematic reviews of fish consumption on all health outcomes.

Methods

The methodological quality of the included meta-analyses and the quality of the evidence were assessed by the Assessment of Multiple Systematic Reviews (AMSTAR) and the grading of recommendations, assessment, development, and evaluation (GRADE) tools, respectively. The umbrella review identified 91 meta-analyses with 66 unique health outcomes, of which 32 outcomes were beneficial, 34 showed nonsignificant associations and only one was harmful (myeloid leukemia).

Results

A total of 17 beneficial associations [all-cause mortality, prostate cancer mortality, cardiovascular disease (CVD) mortality, esophageal squamous cell carcinoma (ESCC), glioma, non-Hodgkin lymphoma (NHL), oral cancer, acute coronary syndrome (ACS), cerebrovascular disease, metabolic syndrome, age-related macular degeneration (AMD), inflammatory bowel disease (IBD), Crohn's disease (CD), triglycerides, vitamin D, high-density lipoprotein (HDL)-cholesterol, and multiple sclerosis (MS)], and eight nonsignificant associations [colorectal cancer (CRC) mortality, esophageal adenocarcinoma (EAC), prostate cancer, renal cancer, ovarian cancer, hypertension, ulcerative colitis (UC), and rheumatoid arthritis (RA)] were evaluated as moderate/high quality of evidence. According to dose-response analyses, consumption of fish, especially fatty types, seems generally safe at one-two servings per week and could exert protective effects.

Conclusions

Fish consumption is often associated with a variety of health outcomes, both beneficial and harmless, but only about 34% of the associations were graded as based on a moderate/high quality of evidence, and additional multicenter high quality randomized controlled trials (RCTs) with a large sample size are needed to verify these findings in the future.

Dietary oily fish intake and progression of diffuse subcortical damage of vascular origin: A longitudinal prospective study in community-dwelling older adults

INTRODUCTION

Oily fish intake may reduce the progression of white matter hyperintensities (WMH) of presumed vascular origin due to their high content of omega-3 polyunsaturated fatty acids and other nutrients. However, information on this relationship is limited. We aimed to assess the association between oily fish intake and WMH progression in older adults living in rural coastal Ecuador.

METHODS

Participants of the Atahualpa Project Cohort received baseline clinical interviews and brain MRIs. Oily fish intake was calculated at every annual door-to-door survey from enrollment to the end of the study. Individuals who also received a follow-up brain MRI were included. Poisson regression models were fitted to assess the incidence rate ratio (IRR) of WMH progression according to the amount of oily fish intake, after adjusting for demographics, level of education and traditional vascular risk factors.

RESULTS

The study included 263 individuals of Amerindian ancestry aged ⩾60 years (mean age: 65.7 ± 6.2 years; 57% women). The mean oily fish intake was 8.3 ± 4 servings per week. Follow-up MRIs demonstrated WMH progression in 103 (39%) individuals after a median follow-up of 6.5 years. A multivariate Poisson regression model showed an inverse relationship between oily fish intake and WMH progression (IRR: 0.89; 95% CI: 0.84-0.95; p < 0.001). A similar model also revealed an inverse relationship between tertiles of oily fish intake and probabilities of WMH progression, which became significant when individuals allocated to the third tertile were compared to those in the first and second tertiles.

CONCLUSION

Study results show an inverse relationship between the amount of oily fish intake and WMH progression in frequent fish consumers of Amerindian ancestry.

Inverse Association Between Variety of Proteins With Appropriate Quantity From Different Food Sources and New-Onset Hypertension

The relationships of the variety and quantity of different sources of dietary proteins with hypertension remain uncertain. We aimed to investigate associations between the variety and quantity of proteins intake from 8 major food sources and new-onset hypertension among 12 177 participants from the China Health and Nutrition Survey. Dietary intake was measured by 3 consecutive 24-hour dietary recalls combined with a household food inventory. The variety score of protein sources was defined as the number of protein sources consumed at the appropriate level, accounting for types and quantity of proteins. New-onset hypertension was defined as systolic blood pressure ≥140 mm Hg and diastolic blood pressure ≥90 mm Hg, or physician-diagnosed hypertension or receiving antihypertensive treatment, during the follow-up. During a median follow-up of 6.1 years, there were U-shaped associations of percentages energy from total, unprocessed or processed red meat-derived, whole grain-derived, and poultry-derived proteins with new-onset hypertension; an reverse J-shaped association of fish-derived protein with new-onset hypertension; L-shaped associations of eggs-derived and legumes-derived proteins with new-onset hypertension; and an reverse L-shaped association of refined grain-derived protein with new-onset hypertension (all P values for nonlinearity <0.001). That is, for each protein, there is a window of consumption (appropriate level) where the risk of hypertension is lower. Moreover, a significantly lower risk of new-onset hypertension was found in those with higher variety score of protein sources (per score increment, hazard ratio, 0.74 [95% CI, 0.72-0.76]). In summary, there was an inverse association between the variety of proteins with appropriate quantity from different food sources and new-onset hypertension.

Production of Dual Inhibitory Hydrolysate by Enzymatic Hydrolysis of Squid Processing By-product

Squid processing by-product contains unutilized abundant proteins. In this study, 6 proteases (pepsin, protamex, trypsin, neutral protease, alkaline protease, and papain) were firstly employed to hydrolyze the squid processing by-product protein. The neutral protease-digested hydrolysate was found to have the most promising ACE (angiotensin-converting enzyme) inhibitory activity. Based on Box-Behnken design, the optimal hydrolysis process was determined to be: 52.4 ℃ of temperature, 5.7 h of time, pH 7.1, and 8151 U/g of enzyme. Under these conditions, the ACE inhibition rate and polypeptide content of the hydrolysate were 84.26% and 229.09 mg/g, respectively. Subsequently, ultrafiltration was performed, and the ACE and renin inhibitory activities of the filtrate (< 1 kDa) were the highest, reaching 87.48 ± 1.76% and 69.72 ± 1.16%, with IC₅₀ values of 1.34 ± 0.12 mg/mL and 1.47 ± 0.06 mg/mL, respectively. However, these activities decreased to 35.15 ± 1.31% and 43.17% ± 1.42%, respectively, after digestion by simulated gastrointestinal juice. Nevertheless, this is the first report representing the neutral protease-digested hydrolysate of squid processing by-product as a potential source of both ACE and renin inhibitors.

Association Between Pulsatile Components of Blood Pressure and Severe Tooth Loss in Rural Ecuador: The Three Villages Study

Background: Arterial hypertension has been associated with severe tooth loss, but differential associations with individual components of blood pressure (BP) have scarcely been investigated. We assessed the independent associations between pulsatile/steady components of BP and severe tooth loss in community-dwelling adults residing in 3 rural Ecuadorian villages. Methods: Individuals aged ≥40 years living in Atahualpa, El Tambo, and Prosperidad were identified during door-to-door surveys. Data collection focused on the number of remaining teeth and measurements of pulsatile/steady components of BP. Multivariate models were fitted to assess independent associations between pulsatile/steady BP components and severe tooth loss, after adjusting for relevant covariates. Results: A total of 1543 individuals were included. Oral exams identified 426 (28%) individuals with severe tooth loss. BP levels ≥140/90 mm Hg were determined in 481 (31%) individuals. The mean pulse pressure (PP) level was 55.3 ± 19 mm Hg. For systolic BP (SBP), the mean level was 133.1 ± 23.5 mm Hg, and for diastolic BP (DBP) it was 77.8 ± 11.5 mm Hg. Univariate models showed significant associations between severe tooth loss and SBP and PP, but not with DBP. However, the significance was taken away in fully adjusted generalized linear models. Age remained as an independent significant covariate in models using SBP and PP. Causal mediation analyses disclosed that percentages of the effect of severe tooth loss mediated by age were 99.5% for SBP and 98.9% for PP. Conclusion: This study shows that age captures most of the effect of the association between pulsatile components of BP and severe tooth loss.

Changes in plasma fatty acids and related biomarkers during transition to an exclusively plant- and fish-based diet in healthy adults

OBJECTIVE

The aim of this study was to examine the time scale of plasma fatty acid changes during transition to an exclusively plant- and fish-based diet in healthy individuals and determine whether there are associated alterations in arachidonic acid (ARA)-derived inflammatory mediators, estimated stearoyl coenzyme A desaturase (SCD) activity, and blood pressure.

METHODS

In pursuit of a religious fast, 36 adults abstained  from eating poultry, meat, dairy products, and eggs, while increasing fish intake for 6 wk. Participants were assessed 1 wk before (W0) and 1 (W1) and 6 (W6) weeks after the diet change.

RESULTS

By W6, fasting plasma long-chain ω-3 polyunsaturated fatty acids (ω-3 LC-PUFAs); docosahexaenoic (DHA) and eicosapentaenoic (EPA) had increased (+67% and +73%, respectively; P ≤ 0.001), with early rise of DHA (+22%), but not EPA at W1.The ω-3 index (sum of DHA and EPA as a percent of total fatty acids) increased from 2.1% to 3.4%. ARA decreased progressively (W1, -9%; W6, -16%; P < 0.001). ARA precursors γ-linolenic and dihomo-γ-linolenic acids also decreased, without changes in the ARA-derived mediators prostaglandin-E2 and leukotriene-B4. Myristic acid decreased at W1 (-37%) and W6 (-40%). There was no consistent change in SCD indices. At W6, systolic and diastolic blood pressure had declined by 8 and 5 mm Hg, respectively (P ≤ 0.013).

CONCLUSIONS

Shifting to a plant- and fish-based diet produces rapid and sustained increases in ω-3 LC-PUFAs and decreases the ω-6 PUFA ARA and its precursors, consistent with a cardio-protective profile. The rapid response suggests that these biomarkers may be useful for assessment of diet interventions.

Omega-3 Polyunsaturated Fatty Acids: Versatile Roles in Blood Pressure Regulation

Significance: Hypertension is characterized as the imbalance of vasoconstriction and vasodilatation. Hypertension is influenced by genetic variation and environmental risk factors, such as unhealthy diet. Clinical trial results suggest that increasing intake of foods rich in n-3 polyunsaturated fatty acids (PUFAs) is beneficial for hypertension. Recent Advances: We summarized recent clinical trials regarding supplementation with n-3 PUFAs to reduce blood pressure (BP) in untreated hypertensive and normotensive subjects and systematically discussed the antihypertension mechanisms of n-3 PUFAs/n-3 oxylipins, including reducing oxidative stress, altering functions of membrane-related proteins, and competing with n-6 PUFAs/n-6 oxylipins in regulating vasodilator release. Critical Issues: Previous studies considered n-3 PUFAs as single molecules with beneficial roles in hypertension. Recently, researchers have paid more attention to the metabolism of n-3 PUFAs and explored molecular mechanisms of n-3 PUFAs and oxylipins derived from n-3 PUFAs in hypertension interventions. Future Directions: Based on the metabolism of n-3 PUFAs/n-3 oxylipins and mechanisms in BP control, we suggested that supplementation of n-3 PUFAs combined with agents targeting PUFA metabolism or the related signal pathways may amplify their effects to treat hypertension and other cardiovascular diseases. Antioxid. Redox Signal. 34, 800-810.

Prevention of Endothelial Dysfunction and Cardiovascular Disease by n-3 Fatty Acids-Inhibiting Action on Oxidative Stress and Inflammation

BACKGROUND

Prospective cohort studies and randomized controlled trials have shown the protective effect of n-3 fatty acids against cardiovascular disease (CVD). The effect of n-3 fatty acids on vascular endothelial cells indicates their possible role in CVD prevention.

OBJECTIVE

Here, we describe the effect of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) on endothelial dysfunction-caused by inflammation and oxidative stress-and their role in the development of CVD.

METHODS

We reviewed epidemiological studies done on n-3 fatty acids in CVD. The effect of DHA and EPA on vascular endothelial cells was examined with regard to changes in various markers, such as arteriosclerosis, inflammation, and oxidative stress, using cell and animal models.

RESULTS

Epidemiological studies revealed that dietary intake of EPA and DHA was associated with a reduced risk of various CVDs. EPA and DHA inhibited various events involved in arteriosclerosis development by preventing oxidative stress and inflammation associated with endothelial cell damage. In particular, EPA and DHA prevented endothelial cell dysfunction mediated by inflammatory responses and oxidative stress induced by events related to CVD. DHA and EPA also increased eNOS activity and induced nitric oxide production.

CONCLUSION

The effects of DHA and EPA on vascular endothelial cell damage and dysfunction may involve the induction of nitric oxide, in addition to antioxidant and anti-inflammatory effects. n-3 fatty acids inhibit endothelial dysfunction and prevent arteriosclerosis. Therefore, the intake of n-3 fatty acids may prevent CVDs, like myocardial infarction and stroke.

On the Association Between Sleep Quality and Arterial Stiffness: A Population Study in Community-Dwelling Older Adults Living in Rural Ecuador (The Atahualpa Project)

STUDY OBJECTIVES

Evidence of an association between atherosclerosis and sleep quality is limited and has not been studied in remote rural settings, where living conditions are different than in urban centers. We aimed to assess the relationship between the aortic pulse wave velocity (PWV) and sleep quality in older adults living in rural Ecuador.

METHODS

Atahualpa residents aged 60 years or older identified during door-to-door surveys, who consented to participate, underwent face-to-face interviews with the Pittsburgh Sleep Quality Index (PSQI) to assess sleep quality. Aortic PWV determinations were performed for arterial stiffness estimation (as a surrogate of atherosclerosis).

RESULTS

A total of 303 individuals were included (mean age: 70.3 ± 7.8 years; 59% women). Univariate logistic regression showed a significant association between the aortic PWV and poor sleep quality (odds ratio [OR] 1.22; 95% confidence interval [CI] 1.07-1.39; P = .003). A multivariate logistic regression model, adjusted for demographics, cardiovascular risk factors, oily fish intake and psychological distress showed a significant association between increased PWV and poor sleep quality (OR 1.59; 95% CI 1.12-2.25; P = .009). Similar significance was noted when the model was adjusted for neuroimaging signatures of cerebral small-vessel disease and stroke (OR 1.47; 95% CI 1.07-2.03; P = .019).

CONCLUSIONS

This study shows a significant independent association between the aortic PWV and poor sleep quality in older adults living in rural Ecuador. Results provide more insights into the relevance of the impact of sleep disorders on cardiovascular diseases.

CLINICAL TRIAL REGISTRATION

The Atahualpa Project has been registered at ClinicalTrials.gov. The identifier number is NCT01627600, and the date was: 10/02/2012.

CITATION

Del Brutto OH, Mera RM, Peñaherrera E, Costa AF, Peñaherrera R, Castillo PR. On the association between sleep quality and arterial stiffness: a population study in community-dwelling older adults living in rural ecuador (the atahualpa project). J Clin Sleep Med. 2019;15(8):1101-1106.

The association between aortic arterial stiffness, carotid intima-media thickness and carotid plaques in community-dwelling older adults: A population-based study

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.

Does menopausal status have an effect on body mass index and blood pressure?

Aim of the study was to understand the relationship of menopausal status with BMI and blood pressure. The study area was selected through multistage sampling technique covering six districts of West Bengal, a state located at the eastern part of India. 1400 participants were selected for the study. The participants were divided into four groups on the basis of menopausal status: early and late perimenopausal; early and late postmenopausal. Results shows that menopausal status was significantly associated with Body Mass Index (BMI) and Mean Arterial Pressure (MAP), after controlling the effect of covariates such as participants' age, reproductive behavior, diet and addiction to tobacco use.

Effects of intact and hydrolysed blue whiting proteins on blood pressure and markers of kidney function in obese Zucker fa/fa rats

PURPOSE

To investigate the effects of diets containing intact or hydrolysed proteins from blue whiting (Micromesistius poutassou) on the development of high blood pressure and markers of kidney function in obese Zucker fa/fa rats which are prone to develop hypertension and renal failure.

METHODS

Male rats were fed isocaloric diets containing either intact blue whiting whole meal (BW-WM), blue whiting protein hydrolysate prepared with Alcalase^® (BW-HA) or blue whiting protein hydrolysate prepared with Protamex^® (BW-HP) as 1/3 of total protein with the remaining 2/3 as casein, or casein as sole protein source (control group). Blood pressure was measured at Day 0 and Day 32. Rats were housed in metabolic cages for 24 h for collection of urine in week 4. After 5 weeks, rats were euthanized and blood was drawn from the heart. The renin and angiotensin-converting enzyme (ACE) inhibition capacities for casein and blue whiting proteins were measured in vitro.

RESULTS

The blood pressure increase was lower in rats fed diets containing blue whiting proteins when compared to the control group, whereas markers of kidney function were similar between all groups. The three blue whiting proteins inhibited renin activity in vitro, whereas casein had no effect. The in vitro ACE inhibition was similar for casein, BW-WM and BW-HP proteins, whereas BW-HA protein was less potent.

CONCLUSION

Blue whiting protein feeding attenuated the blood pressure increase in obese Zucker fa/fa rats, possibly mediated through the renin-angiotensin system and without affecting markers of kidney function.

Cerebrovascular Correlates of Dementia in Community-Dwelling Older Adults Living in Rural Communities - The Three Villages Study. Rationale and Protocol of a Population-Based Prospective Cohort Study

BACKGROUND

Despite the assumption that dementia is increasing in rural areas of Latin America, there is no information on the burden and risk factors leading to dementia in these settings.

AIMS

To assess prevalence and incidence of dementia, and its cerebrovascular correlates in an established cohort of community-dwelling older adults living in rural Ecuador, and to explore the impact of dementia on functional disability and the role of the social determinants of health in the above-mentioned relationships.

DESIGN

Population-based, cohort study with cross-sectional and longitudinal components. Baseline clinical interviews will focus on the assessment of cognitive performance and dementia by means of the clinical dementia rating scale (CDRS). Functional disability and social determinants of health will be correlated with CDRS scores. In addition, participants will undergo interviews and procedures to assess cardiovascular risk factors and signatures of brain damage, cerebral small vessel disease, and other stroke subtypes. The CDRS and the Functional Activities Questionnaire will be administered every year to assess the rate of incident dementia and the severity of functional disability. Neuroimaging studies will be repeated at the end of the study (5 years) to assess the impact of newly appeared cerebral and vascular lesions on cognitive decline.

COMMENT

This study will allow determine whether cerebrovascular diseases are in the path of dementia development in these rural settings. This may prove cost-effective for the development of preventive strategies aimed to control modifiable factors and reduce disability in patients with dementia living in underserved populations.

Dietary Oily Fish Intake and Frailty. A Population-Based Study in Frequent Fish Consumers Living in Rural Coastal Ecuador (the Atahualpa Project)

Oily fish are recommended as part of a healthy diet due to their high content of long-chain omega-3 polyunsaturated fatty acids (ω-3 PUFAs), proteins, and other nutrients. There is preliminary evidence of beneficial effects of ω-3 PUFAs in the prevention of sarcopenia (a major component of frailty). In this study, we aimed to assess the relationship between dietary oily fish intake and a measure of frailty - the Edmonton Frail Scale (EFS) score - in community-dwelling older adults living in rural coastal Ecuador. A total of 363 Atahualpa residents were enrolled. The mean fish servings per week were 8.8 ± 5.2 and mean EFS score was 5 ± 2.8 points. A linear regression model showed no association between the amount of oily fish intake and EFS scores. However, an interaction model, with participants stratified according to their median age and fish intake in quintiles, showed a significant effect for both variables on the EFS score (ß coefficient = 0.104; 95% C.I.: 0.003-0.206; p = 0.044). At the lowest quintile of fish intake, younger individuals have lower EFS scores than their older counterparts. As the consumption of oily fish increases, mean EFS scores margins were found to be progressively reduced in subjects aged 60-69 years but were largely unaffected in persons aged ≥70 years. It appears that oily fish intake has a positive effect on the frailty status of younger subjects but is superseded by the effects of age in the older population.

Clinical and neuroimaging risk factors for cognitive decline in community-dwelling older adults living in rural Ecuador. A population-based prospective cohort study

OBJECTIVE

There is limited information on factors influencing cognitive decline in rural settings from low- and middle-income countries. Using the Atahualpa Project cohort, we aimed to assess the burden of cognitive decline in older adults living in a rural Ecuadorian village.

METHODS

The study included Atahualpa residents aged greater than or equal to 60 years who had a follow-up Montreal Cognitive Assessment (MoCA) repeated at least 1 year after baseline. MoCA decline was assessed by multivariable longitudinal linear models, adjusted for demographics, days between MoCA tests, cardiovascular risk factors, and neuroimaging signatures of structural brain damage.

RESULTS

We included 252 individuals who contributed 923.7 person-years of follow-up (mean: 3.7 ± 0.7 years). The mean baseline MoCA was 19.5 ± 4.5 points, and the follow-up MoCA was 18.1 ± 4.9 points (P = 0.001). Overall, 154 individuals (61%) had lower MoCA scores at follow-up. The best fitted longitudinal linear model showed a decline of follow-up MoCA from baseline (β: 0.14; 95% CI, 0.0-0.21; P < 0.001). High glucose levels, global cortical atrophy, and white matter hyperintensities were independently and significantly associated with greater MoCA decline.

CONCLUSION

This study provides evidence of cognitive decline in older adults living in a rural setting. Main targets for prevention should include glucose control and the control of factors that are deleterious for the development of cortical atrophy and white matter hyperintensities.

Influence of Frailty on Cognitive Decline: A Population-Based Cohort Study in Rural Ecuador

OBJECTIVE

To assess the influence of frailty on cognitive decline.

DESIGN

Population-based prospective cohort study.

SETTINGS/PARTICIPANTS

Community-dwelling older adults living in a rural Ecuadorian village, fulfilling the following criteria: age ≥60 years at baseline Montreal Cognitive Assessment (MoCA) and frailty assessment, a baseline brain magnetic resonance imaging, and a follow-up MoCA performed at least 12 months after the baseline.

MEASURES

Frailty was evaluated by the Edmonton Frailty Scale (EFS) and cognitive performance by MoCA. The relationship between baseline EFS and MoCA decline was assessed by longitudinal linear and fractional polynomial models, adjusted for relevant confounders. The score of the cognitive component of the EFS was subtracted, and an alternative fractional polynomial model was fitted to settle the impact of such cognitive question on the model.

RESULTS

A total of 252 individuals, contributing 923.7 person-years of follow-up (mean: 3.7 ± 0.7 years) were included. The mean EFS score was 4.7 ± 2.5 points. The mean baseline MoCA score was 19.5 ± 4.5 points, and that of the follow-up MoCA was 18.1 ± 4.9 points (P = .001). Overall, 154 (61%) individuals had lower MoCA scores in the follow-up. The best fitted longitudinal linear model showed association between baseline EFS score and MoCA decline (P = .027). There was a continuous increase in MoCA decline in persons with an EFS ≥7 points (nonlinear relationship). Fractional polynomials explained the effect of the EFS on MoCA decline. For the complete EFS score, the β coefficient was 2.43 (95% confidence interval 1.22-3.63). For the effect of the EFS (without its cognitive component) on MoCA decline, the relationship was still significant (β 4.86; 95% confidence interval 2.6-7.13).

CONCLUSIONS/IMPLICATIONS

Over a 3.7-year period, 61% of older adults living in Atahualpa experienced cognitive decline. Such decline was significantly associated with frailty status at baseline. Region-specific risk factors influencing this relationship should be further studied to reduce its burden in rural settings.

Low prevalence of atrial fibrillation in Amerindians: a population-based study in frequent fish consumers living in rural coastal Ecuador (The Atahualpa Project)

BACKGROUND

Information on the burden of atrial fibrillation (AF) in rural areas of developing countries is limited. Here, we aimed to assess AF prevalence in community-dwelling older adults living in rural Ecuador.

METHODS

Atahualpa residents aged ≥60 years (mean age 70.5 ± 8.1 years) underwent 24-h Holter monitoring. Participants belong to the Amerindian ethnic group. The mean height in the study population was 147.9 ± 8.9 cm. Oily fish was a major source of food (mean intake: 8 ± 4 servings/week).

RESULTS

Seven of 298 participants (2.3%) had AF. Persons with AF were older than those without (p = 0.051), but there were no differences in cardiovascular risk factors across groups. None of the seven AF cases had been detected in routine 12-lead ECGs taken at enrollment.

CONCLUSIONS

Prevalence of AF in older Amerindians living in rural Ecuador is low. Both, racially-determined short stature and frequent dietary oily fish intake might explain the low prevalence of AF in this rural setting.

The Role of Brachial Pulse Pressure as an Indicator of Intracranial Atherosclerosis: The Atahualpa Project

INTRODUCTION

Carotid siphon calcifications (CSC) are an important imaging marker of systemic atherosclerosis. Routine assessment of asymptomatic CSC may allow the implementation of intervention strategies before catastrophic cerebrovascular events occur.

AIM

To assess whether brachial PP determinations might independently predicts the presence and severity of CSC in community-dwelling adults.

METHODS

All Atahualpa residents aged ≥40 years were invited for the practice of a non-enhanced CT scan of the head, and those who signed the informed consent and had no contraindications for this exam were enrolled. The brachial PP was calculated by subtracting the mean diastolic pressure from the mean systolic pressure obtained from three different readings with individuals in the sitting position.

RESULTS

Of 830 eligible candidates, 663 (80%) were included. The mean brachial PP was 56.4 ± 19.9 mmHg; 182 persons (27.4%) had PP levels >65 mmHg. CT revealed Grade 1 CSC in 356 (54%), Grade 2 in 141 (21%), Grade 3 in 128 (19%), and Grade 4 in 38 (6%) subjects. Predictive margins of PP (delta method) were significantly lower in individuals with Grade 1 CSC than in the other groups. In the best adjusted linear model, PP levels increased up to 11.7 mmHg as the severity of CSC increased (β 11.71; 95% C.I. 5.36-18.08: p < 0.001).

CONCLUSION

This study provides evidence on the relationship between brachial PP levels and intracranial atherosclerosis. Calculation of the PP may be used for detecting candidates for CT screening, reducing costs during population-based surveys, particularly in remote areas.

Fish, Long-Chain n-3 PUFA and Incidence of Elevated Blood Pressure: A Meta-Analysis of Prospective Cohort Studies

Results from prospective cohort studies on fish or long-chain (LC) n-3 polyunsaturated fatty acid (PUFA) intake and elevated blood pressure (EBP) are inconsistent. We aimed to investigate the summary effects. Pertinent studies were identified from PubMed and EMBASE database through October 2015. Multivariate-adjusted risk ratios (RRs) for incidence of EBP in the highest verses the bottom category of baseline intake of fish or LC n-3 PUFA were pooled using a random-effects meta-analysis. Over the follow-up ranging from 3 to 20 years, 20,497 EBP events occurred among 56,204 adults from eight prospective cohort studies. The summary RR (SRR) was 0.96 (95% CI: 0.81, 1.14; I² = 44.70%) for fish in four studies, and 0.73 (95% CI: 0.60, 0.89; I² = 75.00%) for LC n-3 PUFA in six studies (three studies for biomarker vs. three studies for diet). Circulating LC n-3 PUFA as biomarker was inversely associated with incidence of EBP (SRR: 0.67; 95% CI: 0.55, 0.83), especially docosahexaenoic acid (SRR: 0.64; 95% CI: 0.45, 0.88), whereas no significant association was found for dietary intake (SRR: 0.80; 95% CI: 0.58, 1.10). The present finding suggests that increased intake of docosahexaenoic acid to improve its circulating levels may benefit primary prevention of EBP.