Effect of improving dietary quality on carotid intima media thickness in subjects with type 1 and type 2 diabetes: a 12-mo randomized controlled trial

Nutritional Status, Dietary Intake, and Nutrition-Related Interventions Among Older Adults With Type 1 Diabetes: A Systematic Review and Call for More Evidence Toward Clinical Guidelines

There is an emerging population of older adults (≥65 years) living with type 1 diabetes. Optimizing health through nutrition during this life stage is challenged by multiple and ongoing changes in diabetes management, comorbidities, and lifestyle factors. There is a need to understand nutritional status, dietary intake, and nutrition-related interventions that may maximize well-being throughout the life span in type 1 diabetes, in addition to nutrition recommendations from clinical guidelines and consensus reports. Three reviewers used Cochrane guidelines to screen original research (January 1993-2023) and guidelines (2012-2023) in two databases (MEDLINE and CENTRAL) to characterize nutrition evidence in this population. We found limited original research explicitly focused on nutrition and diet in adults ≥65 years of age with type 1 diabetes (six experimental studies, five observational studies) and meta-analyses/reviews (one scoping review), since in the majority of analyses individuals ≥65 years of age were combined with those age ≥18 years, with diverse diabetes durations, and also individuals with type 1 and type 2 diabetes were combined. Further, existing clinical guidelines (n = 10) lacked specificity and evidence to guide clinical practice and self-management behaviors in this population. From a scientific perspective, little is known about nutrition and diet among older adults with type 1 diabetes, including baseline nutrition status, dietary intake and eating behaviors, and the impact of nutrition interventions on key clinical and patient-oriented outcomes. This likely reflects the population's recent emergence and unique considerations. Addressing these gaps is foundational to developing evidence-based nutrition practices and guidelines for older adults living with type 1 diabetes.

Low adherence to the Mediterranean diet is associated with increased prevalence and number of atherosclerotic plaques in the ILERVAS cohort

BACKGROUND AND AIMS

Current research on the association between dietary patterns and subclinical atherosclerotic disease (SAD) is still limited, and published results are inconsistent and often consist of small population sizes. We aimed to evaluate the association between the Mediterranean diet (MDiet) and SAD in a large cohort of Mediterranean individuals.

METHODS

This was a cross-sectional study that included 8116 subjects from the ILERVAS cohort. The presence of atherosclerotic plaques (AP) was assessed by ultrasound examination. Adherence to the MDiet was assessed using the 14-item Mediterranean Diet Adherence Score (MEDAS). Inclusion criteria were subjects with at least one cardiovascular risk factor. Exclusion criteria were a clinical history of diabetes, chronic kidney disease, or a prior cardiovascular event. Bivariable and multivariable models were performed.

RESULTS

Compared with subjects without SAD, participants with SAD were older and had a higher frequency of smoking habit, hypertension, dyslipidemia, HbA1c and waist circumference. The adjusted multivariable analysis showed that a higher MEDAS was associated with a lower risk of AP (incidence rate ratios [IRR] 0.97, 95% CI [0.96-0.98]; p<0.001). Furthermore, moderate or high adherence to the MDiet was associated with a lower number of AP compared with a low MDiet adherence (IRR 0.90, 95% CI [0.87-0.94]; p<0.001). In both models, female sex was associated with a lower risk of AP.

CONCLUSIONS

Our findings point to a potentially protective role of MDiet for SAD in a Mediterranean population with low-to-moderate cardiovascular risk. Further research is needed to establish a causal relationship between both variables.

Healthy lifestyle changes favourably affect common carotid intima-media thickness: the Healthy Lifestyle Community Programme (cohort 2)

Common carotid intima-media thickness (ccIMT) progression is a risk marker for cardiovascular disease (CVD), whereas healthy lifestyle habits are associated with lower ccIMT. The objective of the present study was to test whether a healthy lifestyle intervention can beneficially affect ccIMT progression. A community-based non-randomised, controlled lifestyle intervention was conducted, focusing on a predominantly plant-based diet (strongest emphasis), physical activity, stress management and social health. Assessments of ccIMT were made at baseline, 6 months and 1 year. Participants had an average age of 57 years and were recruited from the general population in rural northwest Germany (intervention: n 114; control: n 87). From baseline to 1 year, mean ccIMT significantly increased in both the intervention (0⋅026 [95 % CI 0⋅012, 0⋅039] mm) and control group (0⋅045 [95 % CI 0⋅033, 0⋅056] mm). The 1-year trajectory of mean ccIMT was lower in the intervention group (P = 0⋅022; adjusted for baseline). In a subgroup analysis with participants with high baseline mean ccIMT (≥0⋅800 mm), mean ccIMT non-significantly decreased in the intervention group (-0⋅016 [95 % CI -0⋅050, 0⋅017] mm; n 18) and significantly increased in the control group (0⋅065 [95 % CI 0⋅033, 0⋅096] mm; n 12). In the subgroup, the 1-year trajectory of mean ccIMT was significantly lower in the intervention group (between-group difference: -0⋅051 [95 % CI -0⋅075, -0⋅027] mm; P < 0⋅001; adjusted for baseline). The results indicate that healthy lifestyle changes may beneficially affect ccIMT within 1 year, particularly if baseline ccIMT is high.

Cardiovascular Risk Management in Type 1 Diabetes

PURPOSE OF REVIEW

Type 1 diabetes mellitus (T1DM) is associated with increased mortality, with premature cardiovascular disease (CVD) a major factor. To date, research has identified multiple risk factors for this excess CVD liability. However, gaps remain in our understanding of the underlying mechanisms.

RECENT FINDINGS

T1DM is generally diagnosed at a young age. Since cardiovascular complications often only manifest at a later stage of life, there is generally less focus in earlier years on reducing CVD risk for affected individuals. This is an area that requires improvement as risk factors might be managed from earlier age to reduce later development of CVD. In this review, we discuss the evidence for cardiovascular risk factors, risk prediction models, candidate surrogate measurements and CVD risk management.

What Can We Change in Diet and Behaviour in Order to Decrease Carotid Intima-Media Thickness in Patients with Obesity?

Atherosclerosis-considered the major cause of cardiovascular diseases (CVDs)-is strongly associated with obesity, to which it strongly contributes. Moreover, atherosclerosis is characterised by a long asymptomatic phase, and its progression can lead to serious cardiovascular (CV) events. The carotid intima-media thickness (cIMT) has been determined as a predictor of CV events, as well as a marker of subclinical atherosclerosis, and has been used in clinical trials as an alternative assessment method or a surrogate endpoint. It should be noted that several behavioural approaches can directly influence the cIMT values, and decrease or increase the CV risk. In our paper, we aimed to summarize the current knowledge regarding IMT measurement among patients with obesity as a risk group-also in terms of the obesity paradox where the diagnosis of subclinical atherosclerosis is especially essential and implements the early therapeutic approach. We also summarized behavioural, modifiable factors, such as the Mediterranean diet, the Dietary Approach to Stop Hypertension Diets, body weight reduction or the intake of micro- and macronutrients, with a particular focus on the studies where the cIMT values were one of the outcomes. In order to collect the literature data related to the presented topic, the PubMed database was explored.

Effect of a 6-Month Controlled Lifestyle Intervention on Common Carotid Intima-Media Thickness

OBJECTIVES

The intima-media thickness of the common carotid artery (ccIMT) is an established risk marker for cardiovascular disease (CVD). However, it is unclear whether lifestyle interventions can easily demonstrate an improvement in ccIMT. The objective was to test if our intervention would beneficially affect ccIMT (among other CVD markers).

DESIGN

Non-randomized controlled trial.

SETTING

Rural northwest Germany.

PARTICIPANTS

Middle-aged and elderly participants from the general population (intervention: n = 114; control: n = 87).

INTERVENTION

A community-based, 6-month controlled lifestyle intervention focusing on four areas of lifestyle change: a plant-based diet, physical activity, stress management, and an improved social life. A strong emphasis was on dietary change.

MEASUREMENTS

We tested whether ccIMT change from baseline to 6 months was different between groups.

RESULTS

With all participants included, no significant difference in mean ccIMT change between groups was observed (p = 0.708). However, in a subgroup analysis with participants with high baseline mean ccIMT (≥0.800 mm) a significant difference in mean ccIMT change between intervention (-0.023 [95% CI -0.052, 0.007] mm; n = 22; baseline mean ccIMT: 0.884 ± 0.015 mm) and control (0.041 [95% CI 0.009, 0.073] mm; n = 13; baseline mean ccIMT: 0.881 ± 0.022 mm) was observed (p = 0.004). Adjusting for potential confounders did not substantially alter the results.

CONCLUSION

The results indicate that healthy lifestyle changes can beneficially affect ccIMT within 6 months and that such a beneficial effect may be more easily demonstrated if participants with high baseline ccIMT are recruited. The observed effect is of relevance for the prevention of CVD events, including myocardial infarction and stroke.

Association between diet quality indices and arterial stiffness in youth with type 1 diabetes: SEARCH for Diabetes in Youth Nutrition Ancillary Study

AIMS

We studied the association of three distinct diet quality indices and two measures of arterial stiffness in youth and young adults (YYA) aged 10 to 30 with T1D.

METHODS

Cross-sectional (n = 1421) and longitudinal (n = 520) analyses were conducted in T1D YYA participating in the SEARCH for Diabetes in Youth Study. The diet quality indices included the Dietary Approaches to Stop Hypertension (DASH) index, the Healthy Eating Index 2015 (HEI-2015), and a modified Mediterranean Diet Quality Index (mKIDMED). Arterial stiffness was measured with pulse wave velocity (PWV) and augmentation index (AIx) obtained using a SphygmoCor-Vx device and tonometer.

RESULTS

Average diet quality was moderate to poor, with mean scores of 41 (DASH, range 0-80), 55 (HEI-2015, range 0-100), 3.7 (mKIDMED, range - 3-12). None of the diet quality scores was associated with the central PWV or Aix, independent of demographic, clinical and lifestyle factors, body mass index and HbA1c. Longitudinal data yielded consistent findings with cross-sectional results.

CONCLUSIONS

This study suggests that diet quality may not function as an independent risk factor for arterial stiffening in YYA with T1D. These findings do not diminish the importance of consuming a quality diet for the management of diabetes, as demonstrated in previous work.

Traditional Risk Factors are Causally Related to Carotid Intima-Media Thickness Progression: Inferences from Observational Cohort Studies and Interventional Trials

In the present review, associations between traditional vascular risk factors (VRFs) and carotid intimamedial thickness progression (C-IMTp) as well as the effects of therapies for VRFs control on C-IMTp were appraised to infer causality between each VRF and C-IMTp. Cohort studies indicate that smoking, binge drinking, fatness, diabetes, hypertension and hypercholesterolemia are associated with accelerated C-IMTp. An exception is physical activity, with mixed data. Interventions for the control of obesity, diabetes, hypertension and hypercholesterolemia decelerate C-IMTp. Conversely, scarce information is available regarding the effect of smoking cessation, stop of excessive alcohol intake and management of the metabolic syndrome. Altogether, these data support a causative role of several traditional VRFs on C-IMTp. Shortcomings in study design and/or ultrasonographic protocols may account for most negative studies, which underlines the importance of careful consideration of methodological aspects in investigations using C-IMTp as the outcome.

Science dialogue mapping of knowledge and knowledge gaps related to the effects of dairy intake on human cardiovascular health and disease

Dairy has been described as everything from a superfood to a poison; yet, arguments, assumptions, and data justifying these labels are not always clear. We used an issue-based information system, "dialogue mapping™," to summarize scientific points of a live panel discussion on the putative effects of dairy on cardiovascular diseases (CVD) from a day-long session among experts in nutrition and CVD. Dialogue mapping captures relations among ideas to explicitly, logically, and visually connect issues/questions, ideas, pro/con arguments, and agreements, even if discussed at different times. Experts discussed two propositions: for CVD risk, consumption of full-fat dairy products 1) should be minimized, in part because of their saturated fat content, or 2) need not be minimized, despite their saturated fat content. The panel discussed the dairy-CVD relation through blood lipids, diabetes, obesity, energy balance, blood pressure, dairy bioactives, biobehavioral components, and other putative causal pathways. Associations and effects reported in the literature have varied by fat content of dairy elements considered, study design, intake methods, and biomarker versus disease outcomes. Two conceptual topics emerged from the discussion: 1) individual variability: whether recommendations should be targeted only to those at high CVD risk; 2) quality of evidence: whether data on dairy-CVD relations are strong enough for reliable conclusions-positive, negative, or null. Future procedural improvements for science dialog mapping include using singular rather than competing propositions for discussion.

Salt consumption by Australian adults: a systematic review and meta-analysis

OBJECTIVE

Salt reduction is a public health priority because it is a leading contributor to the global burden of disease. As in Australia there is uncertainty about the current level of salt intake, we sought to estimate current levels.

STUDY DESIGN

Random effects meta-analysis of data from 31 published studies and one unpublished dataset that reported salt or sodium consumption by Australian adults on the basis of 24-hour urine collections or dietary questionnaires.

DATA SOURCES

MEDLINE (via Ovid) and EMBASE (to August 2016).

DATA SYNTHESIS

Thirty-one published studies and one unpublished dataset (1989-2015; 16 836 individuals) were identified. The mean weighted salt consumption estimated from 24-hour urine collections was 8.70 g/day (95% CI, 8.39-9.02 g/day); after adjusting for non-urinary salt excretion, the best estimate of salt intake in Australia is 9.6 g/day. The mean weighted intake was 10.1 g/day (95% CI, 9.68-10.5 g/day) for men and 7.34 g/day (95% CI, 6.98-7.70 g/day) for women. Mean weighted consumption was 6.49 g/day (95% CI, 5.94-7.03 g/day) when measured with diet diaries, 6.76 g/day (95% CI, 5.48-8.05 g/day) when assessed with food frequency questionnaires, and 6.73 g/day (95% CI, 6.34-7.11) when assessed by dietary recall. Salt intake had not decreased between 1989 and 2015 (R² = -0.02; P = 0.36).

CONCLUSION

Salt intake in Australian adults exceeds the WHO-recommended maximum of 5 g/day and does not appear to be declining. Measuring salt intake with methods based on self-reporting can substantially underestimate consumption. The data highlight the need for ongoing action to reduce salt consumption in Australia and robust monitoring of population salt intake.

Dietary quality and carotid intima media thickness in type 1 and type 2 diabetes: Follow-up of a randomised controlled trial

BACKGROUND AND AIMS

The relationship between dietary intake and carotid intima media thickness (IMT) and pulse wave velocity (PWV) in individuals with type 1 and type 2 diabetes has not been well studied. We investigated the association between dietary intake and common carotid artery intima media thickness (CCA IMT) and PWV in a cohort with type 1 and type 2 diabetes.

METHODS AND RESULTS

A one-year randomised controlled trial was conducted to investigate the effect of improving dietary quality on CCA IMT. These subjects were followed up again approximately 12 months after the completion of the trial (i.e. approximately 24 month since baseline). The study cohort included 87 subjects that had dietary intake and CCA IMT measured at baseline and after a mean of 2.3 years' follow-up. PWV was measured in a subsample of this cohort. Age and baseline mean CCA IMT were strongly associated with mean CCA IMT at 24 months. After adjustment for age and baseline mean CCA IMT, baseline consumption of carbohydrate (r = -0.28; p = 0.01), sugars (r = -0.27; p = 0.01), fibre (r = -0.26; p = 0.02), magnesium (r = -0.25; p = 0.02) and the Alternate Health Eating Index (AHEI) score (r = -0.23; p = 0.03) were inversely associated with mean CCA IMT at 24 months. Mixed linear modelling showed an interaction between mean CCA IMT and AHEI at baseline (p = 0.024). Those who were in the highest AHEI tertile at baseline had greater CCA IMT regression at 24 months compared to those in the lowest tertile, after adjustment for baseline age, BMI, smoking pack years, time since diabetes diagnosis, and mean arterial pressure at baseline (mean -0.043 mm; 95% CI -0.084, -0.003; p = 0.029).

CONCLUSIONS

In this prospective analysis greater diet quality at baseline, as measured by the AHEI, was associated with greater CCA IMT regression after approximately two years. This suggests that greater diet quality is associated with better longer term vascular health in individuals with type 1 and type 2 diabetes.

Cruciferous and Total Vegetable Intakes Are Inversely Associated With Subclinical Atherosclerosis in Older Adult Women

Background

Dietary patterns rich in fruits and vegetables are considered to reduce atherosclerotic disease presentation and are reported to be inversely associated with subclinical measures of atherosclerosis, such as carotid artery intima‐media thickness (IMT) and plaque. However, the effect of vegetable intake alone, and relationships to specific types of vegetables containing different phytochemical profiles, is important. The aim of this study was to investigate the associations of total vegetable intake and specific vegetables grouped according to phytochemical constituents with common carotid artery IMT (CCA‐IMT) and carotid plaque severity in a cohort of older adult women (aged ≥70 years).

Methods and Results

Total vegetable intake was calculated at baseline (1998) using a validated food frequency questionnaire. Vegetable types included cruciferous, allium, yellow/orange/red, leafy green, and legumes. In 2001, CCA‐IMT (n=954) and carotid focal plaque (n=968) were assessed using high‐resolution B‐mode carotid ultrasonography. Mean (SD) total vegetable intake was 199.9 (78.0) g/d. Women consuming ≥3 servings of vegetables each day had ≈4.6% to 5.0% lower mean CCA‐IMT (P=0.014) and maximum CCA‐IMT (P=0.004) compared with participants consuming <2 servings of vegetables. For each 10 g/d higher in cruciferous vegetable intake, there was an associated 0.006 mm (0.8%) lower mean CCA‐IMT (P<0.01) and 0.007 mm (0.8%) lower maximum CCA‐IMT (P<0.01). Other vegetable types were not associated with CCA‐IMT (P>0.05). No associations were observed between vegetables and plaque severity (P>0.05).

Conclusions

Increasing vegetables in the diet with a focus on consuming cruciferous vegetables may have benefits for the prevention of subclinical atherosclerosis in older adult women.

Clinical Trial Registration

URL: http://www.anzctr.org.au. Unique identifier: ACTRN12615000750583.

Dietary Modification Trial in Community-Dwelling Japanese Elderly: A Pilot Study

Background

This study examined the effects of 6-month nutrition education programs for community-dwelling elderly.

Methods

This study enrolled 50 community-dwelling elderly who regularly visit outpatient clinics. The programs had three goals: salt reduction, increase in dietary fiber, and adequate protein intake. Since it would be difficult for elderly to achieve all goals concurrently, a single goal was chosen by participants themselves. Anthropometric measurements, blood sampling, and assessment of dietary intake were performed at baseline, 3 months, and 6 months.

Results

The nutrition education program for salt reduction was well accepted by the participants and the amount of daily salt intake showed median value of 9.6 g at baseline, 8.0 g at 3 months and 8.1 g at 6 months (P = 0.005). The amount of dietary fiber intake only slightly increased after taking the nutrition program (median value of 13.4 g at baseline, 15.3 g at 3 months and 15.5 g at 6 months; P = 0.695), because of difficulties in introducing new food options to the diet. After taking the adequate protein intake program, participants showed small decreases in protein (a modification from 1.24 g/kg IBW to 1.20 g/kg IBW) and salt intake (8.2 to 7.3 g) at 3 months, but the effects were not sustained at 6 months.

Conclusion

This nutrition education program focusing on a single nutrient may serve as a strategy to successfully reduce salt intake and improve systolic blood pressure control in community-dwelling elderly individuals who regularly visit outpatient clinics. In our view, dietary and lifestyle habits should be taken into account as much as possible in nutrition education for elderly individuals.

Association between dairy intake, lipids and vascular structure and function in diabetes

AIM

To determine lipid species that change in response to a change in dairy consumption. In addition, to investigate whether dairy associated lipid species are correlated with changes in measures of vascular structure and function.

METHODS

A 12-mo randomised controlled trial was conducted to determine the effect of increased consumption of fruit, vegetables and dairy, compared to usual diet, on measures of vascular structure and function in adults with type 1 and type 2 diabetes (n = 108). This paper comprises post-hoc analyses investigating the relationship between dairy intake, serum lipid species and vascular health. Central and peripheral blood pressure, carotid femoral pulse wave velocity, augmentation index, serum lipid species and dietary intake were measured at baseline and 3-mo. Common carotid artery intima media thickness was measured at baseline and 12-mo.

RESULTS

Serum lipid species [lysophosphatidylcholine (LPC) 14:0, LPC 15:0, LPC 16:1, phosphatidylcholine (PC) 29:0 PC 30:0, PC 31:0 and cholesterol ester (CE) 14:0] were associated with the change in full fat dairy consumption (rho 0.19-0.25; P < 0.05). The 3-mo change in some lipids was positively associated with the 3-mo change in central systolic [LPC 14:0 (rho 0.30; P = 0.007), PC 30:0 (rho 0.28; P = 0.010)] and diastolic blood pressure [LPC 14:0 (rho 0.32; P = 0.004), LPC 15:0 (rho 0.23; P = 0.04), LPC 16:1 (rho 0.23; P = 0.035), PC 29:0 (rho 0.28; P = 0.01), PC 30:0 (rho 0.36; P = 0.001), PC 31:0 (rho 0.30; P = 0.007)] and 12-mo change in common carotid artery intimal medial thickness [CE 14:0 (rho 0.22; P = 0.02)]. Pulse wave velocity and augmentation index were unrelated to dairy and lipid species.

CONCLUSION

An increase in dairy associated lipids appears to be associated with an increase in blood pressure and common carotid intimal medial thickness.

Effect of Improving Dietary Quality on Arterial Stiffness in Subjects with Type 1 and Type 2 Diabetes: A 12 Months Randomised Controlled Trial

People with diabetes have accelerated arterial stiffening. The aim of this study was to determine the effect of increasing fruit, vegetable and dairy intake for 12 months on carotid femoral pulse wave velocity (cfPWV), augmentation index (AIx), and central blood pressure (cBP), compared to a usual diet control, in people with type 1 and type 2 diabetes. In a 12 months randomised controlled trial, cfPWV, AIx and cBP were measured every 3 months. The intervention group received dietary counselling to increase consumption of fruit (+1 serving/day; 150 g/day), vegetables (+2 servings/day; 150 g/day) and dairy (+1 serving/day; 200–250 g/day) at baseline, 1, 3, 6 and 9 months. The control group continued on their usual diet. One hundred and nine participants were randomised and 92 (intervention n = 45; control n = 47) completed. At 3 months, fruit (184 g/day; p = 0.001) and dairy (83 g/day; p = 0.037) intake increased in the intervention group compared with the control group but this increase was not maintained at 12 months. After adjustment for baseline measurements there was no time by treatment effect for central systolic or diastolic BP, AIx or cfPWV. A time effect existed for AIx which modestly increased over time. Peripheral diastolic BP and central pulse pressure were improved in the intervention group compared with the control group at 12 months. In the cohort with type 1 and type 2 diabetes, improving dietary quality by increasing consumption of fruit, vegetables and dairy did not improve cBP, AIx or cfPWV, compared with a control group continuing on their usual diet, after 12 months.