Association of physical activity with all-cause mortality and incident and prevalent cardiovascular disease among patients with type 1 diabetes: the EURODIAB Prospective Complications Study

A Cross-sectional Study on the Impact of Educational Status on Physical Activity Level in Danish and English Adults With Type 1 Diabetes

OBJECTIVES

Physical activity is associated with improved health in people with type 1 diabetes. However, physical activity level may be associated with socioeconomic status. The primary aim of this study was to investigate the association between education level and physical activity level among people with type 1 diabetes.

METHODS

In this cross-sectional study, data on physical activity level (high or low) was measured using the Saltin-Grimby Physical Activity Level Scale, and education level (low, medium, or high) was self-reported.

RESULTS

Respondents were recruited from outpatient clinics (Steno Diabetes Centre Aarhus, Denmark; Nordsjællands Hospital, Denmark; or Sheffield Diabetes and Endocrine Centre, United Kingdom), by health-care personnel from September 2019 to July 2021. A total of 324 people with type 1 diabetes were included (54% male, median age 50 years [interquartile range 30-60 years]). Education level was low in 10%, medium in 33%, and high in 57%. A logistic regression analysis, adjusted for age, sex, cohabitation status and nationality, found that a medium vs. high education level was associated with lower odds of a high physical activity level (odds ratio [OR] 0.55, 95% confidence interval [CI] 0.32-0.94, p=0.029), while no association was found for low vs. high education level with high physical activity level (OR 0.56, 95% CI 0.25-1.29, p=0.173).

CONCLUSIONS

Medium education level compared with a high education level was associated with a lower level of physical activity in people with type 1 diabetes. Health-care professionals are advised to be attentive of physical activity levels among people with type 1 diabetes.

Combined intake of caffeine and low-dose glucose to reduce exercise-related hypoglycaemia in individuals with type 1 diabetes on ultra-long-acting insulin degludec: A randomized, controlled, double-blind, cross-over trial

AIM

To evaluate whether caffeine combined with a moderate amount of glucose reduces the risk for exercise-related hypoglycaemia compared with glucose alone or control in adult people with type 1 diabetes using ultra-long-acting insulin degludec.

MATERIALS AND METHODS

Sixteen participants conducted three aerobic exercise sessions (maximum 75 min) in a randomized, double-blind, cross-over design. Thirty minutes before exercise, participants ingested a drink containing either 250 mg of caffeine + 10 g of glucose + aspartame (CAF), 10 g of glucose + aspartame (GLU), or aspartame alone (ASP). The primary outcome was time to hypoglycaemia.

RESULTS

There was a significant effect of the condition on time to hypoglycaemia (χ2 = 7.674, p = .0216). Pairwise comparisons revealed an 85.7% risk reduction of hypoglycaemia for CAF compared with ASP (p = .044). No difference was observed between GLU and ASP (p = .104) or between CAF and GLU (p = .77). While CAF increased glucose levels during exercise compared with GLU and ASP (8.3 ± 1.9 mmol/L vs. 7.7 ± 2.2 mmol/L vs. 5.8 ± 1.4 mmol/L; p < .001), peak plasma glucose levels during exercise did not differ between CAF and GLU (9.3 ± 1.4 mmol/L and 9.1 ± 1.6 mmol/L, p = .80), but were higher than in ASP (6.6 ± 1.1 mmol/L; p < .001). The difference in glucose levels between CAF and GLU was largest during the last 15 min of exercise (p = .002). Compared with GLU, CAF lowered perceived exertion (p = .023).

CONCLUSIONS

Pre-exercise caffeine ingestion combined with a low dose of glucose reduced exercise-related hypoglycaemia compared with control while avoiding hyperglycaemia.

The Need to Prioritize Education and Resources to Support Exercise in Type 1 Diabetes: Results of an Australian Survey of Adults With Type 1 Diabetes and Health Providers

OBJECTIVES

Regular exercise is recommended for people with type 1 diabetes (PWD) to improve their health, but many do not meet recommended exercise targets. Educational resources supporting PWD to exercise exist, but their value is unclear. To determine the need for improved exercise resources in Australia, we surveyed adult PWD and health providers (HPs) about their confidence in managing type 1 diabetes (T1D) around exercise, barriers to exercise, and the adequacy of current resources.

METHODS

Australian adult PWD and HPs completed surveys to rate the importance of exercise in T1D management, confidence in managing T1D around exercise, barriers to giving and receiving education, resources used, and what form new resources should take.

RESULTS

Responses were received from 128 PWD and 122 HPs. Both groups considered exercise to be important for diabetes management. PWD cited time constraints (57%) and concern about dysglycemia (43%) as barriers to exercise, and many lacked confidence in managing T1D around exercise. HPs were more confident, but experienced barriers to providing advice, and PWD did not tend to rely on this advice. Instead, 72% of PWD found continuous glucose monitoring most helpful. Both groups desired better resources to support exercise in T1D, with PWD preferring to obtain information through a structured education program and HPs through eLearning.

CONCLUSIONS

Australian HPs and PWD appreciate the importance of exercise in T1D management and express a clear desire for improved educational resources. Our findings provide a basis for developing a comprehensive package of resources for both adult PWD and HPs, to support exercise in PWD.

Serum MicroRNA-191-5p Levels in Vascular Complications of Type 1 Diabetes: The EURODIAB Prospective Complications Study

CONTEXT

MicroRNA-191-5p regulates key cellular processes involved in the pathogenesis of diabetic complications such as angiogenesis, extracellular matrix deposition, and inflammation. However, no data on circulating microRNA-191-5p in the chronic complications of diabetes are available.

OBJECTIVE

To assess whether serum levels of microRNA-191-5p were associated with micro- and macrovascular disease in a large cohort of subjects with type 1 diabetes mellitus (DM1) from the EURODIAB Prospective Complication Study.

DESIGN AND SETTING

Levels of microRNA-191-5p were measured by quantitative PCR in 420 patients with DM1 recruited as part of the cross-sectional analysis of the EURODIAB Prospective Complication Study. Cases (n = 277) were subjects with nephropathy and/or retinopathy and/or cardiovascular disease (CVD). Controls (n = 143) were patients without complications. Logistic regression analysis was performed to evaluate the potential independent association of microRNA-191-5p levels with chronic complications of diabetes.

RESULTS

Levels of microRNA-191-5p were significantly reduced (P < .001) in cases compared with controls even after adjustment for age, sex, and diabetes duration. Logistic regression analysis revealed that microRNA-191-5p was negatively associated with a 58% reduced odds ratio (OR) of chronic diabetes complications, specifically CVD, micro-macroalbuminuria, and retinopathy (OR, 0.42; 95% CI, 0.23-0.77), independent of age, sex, physical activity, educational levels, diabetes duration, glycated hemoglobin, total insulin dose, hypertension, smoking, total cholesterol, albumin excretion rate, estimated glomerular filtration rate, serum vascular cell adhesion molecule-1, and tumor necrosis factor-α. Analyses performed separately for each complication demonstrated a significant independent association with albuminuria (OR, 0.36; 95% CI, (0.18-0.75) and CVD (OR, 0.34; 95% CI, 0.16-0.70).

CONCLUSIONS

In DM1 subjects, microRNA-191-5p is inversely associated with vascular chronic complications of diabetes.

Physical Activity and Risk of Major Diabetes-Related Complications in Individuals With Diabetes: A Systematic Review and Meta-Analysis of Observational Studies

BACKGROUND

Physical activity is a cornerstone in diabetes management; however, evidence synthesis on the association between physical activity and long-term diabetes-related complications is scarce.

PURPOSE

To summarize and evaluate findings on physical activity and diabetes-related complications, we conducted a systematic review and meta-analysis.

DATA SOURCES

We searched PubMed, Web of Science, and the Cochrane Library for articles published up to 6 July 2021.

STUDY SELECTION

We included prospective studies investigating the association between physical activity and incidence of and mortality from diabetes-related complications, i.e., cardiovascular disease (CVD), coronary heart disease, cerebrovascular events, heart failure, major adverse cardiovascular events, and microvascular complications such as retinopathy and nephropathy, in individuals with diabetes.

DATA EXTRACTION

Study characteristics and risk ratios with 95% CIs were extracted. Random-effects meta-analyses were performed, and the certainty of evidence and risk of bias were evaluated with use of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) and Risk Of Bias In Non-randomised Studies - of Interventions (ROBINS-I) tools.

DATA SYNTHESIS

Overall, 31 studies were included. There was moderate certainty of evidence that high versus low levels of physical activity were inversely associated with CVD incidence, CVD mortality (summary risk ratio 0.84 [95% CI 0.77, 0.92], n = 7, and 0.62 [0.55, 0.69], n = 11), and microvascular complications (0.76 [0.67, 0.86], n = 8). Dose-response meta-analyses showed that physical activity was associated with lower risk of diabetes-related complications even at lower levels. For other outcomes, similar associations were observed but certainty of evidence was low or very low.

LIMITATIONS

Limitations include residual confounding and misclassification of exposure.

CONCLUSIONS

Physical activity, even below recommended amounts, was associated with reduced incidence of diabetes-related complications.

Decreased Diastolic Blood Pressure and Average Grip Strength in Adults With Type 1 Diabetes Compared With Controls: An Analysis of Data From the Canadian Longitudinal Study on Aging

OBJECTIVES

Our aim in this study was to determine whether aging individuals with type 1 diabetes (T1D) have differences in cardiovascular health, assessed by blood pressure, and skeletal muscle function, assessed by grip strength, compared with matched nondiabetic controls (CON).

METHODS

This investigation was a retrospective cohort analysis using baseline and 3-year follow-up data from the Canadian Longitudinal Study on Aging. Bivariate and multivariate regression analyses were used to examine the association between sociodemographic, health, behavioural and T1D-specific variables on blood pressure and grip strength in T1D and CON groups. Generalized estimating equations were used to model the average population changes in blood pressure and grip strength from baseline to follow up.

RESULTS

The sample included 126 individuals (63 T1D and 63 CON). Systolic blood pressure was not significantly different between groups at baseline or follow up (p>0.05). However, compared with CON, diastolic blood pressure was significantly lower at both time-points in the T1D group (p<0.001). Grip strength was consistently lower among persons with T1D (p=0.03). In the multivariate regression model, body mass index, age and sex were significantly associated with diastolic blood pressure and grip strength in both groups. In the T1D group, disease duration accounted for a large proportion of the variance in diastolic blood pressure and grip strength (17% and 9%, respectively). The rate of decline in diastolic blood pressure and grip strength did not differ between groups (p>0.05).

CONCLUSIONS

Diastolic blood pressure and grip strength appear to be consistently lower and differentially regulated in individuals with T1D vs CON. Aging individuals with T1D may be at risk of premature morbidity and mortality.

Determinants of physical activity among 6856 individuals with diabetes: a nationwide cross-sectional study

INTRODUCTION

The aims of this cross-sectional study were to (1) describe habitual physical activity and adherence to WHO recommendations, and (2) investigate the association of comorbidity, obesity, stress, and health-related quality of life (HRQoL) with moderate to vigorous physical activity (MVPA) among individuals with diabetes.

RESEARCH DESIGN AND METHODS

This study included 6856 participants with diabetes from the Danish National Health Survey from 2017. The primary outcome measure was weekly MVPA. Exposures included self-reported number of conditions, body mass index (BMI), perceived stress, and HRQoL. Mean difference in MVPA across exposures was estimated by multiple linear regression analyses.

RESULTS

Forty per cent of individuals with diabetes were not adherent to WHO recommendations for physical activity. Individuals with diabetes had higher BMI, more comorbidities, higher perceived stress, and lower HRQoL. Individuals with three or more comorbidities were significantly associated with lower weekly MVPA (-0.48 hours/week, 95% CI -0.88 to -0.07) compared with individuals with no comorbidity. Furthermore, overweight or obese (class I-III) individuals engaged in significantly less weekly MVPA (obese class III vs normal weight: -1.98 hours/week, 95% CI -2.49 to -1.47). Higher perceived stress was significantly associated with lower weekly MVPA (-1.76 hours/week, 95% CI -2.18 to -1.34) versus low perceived stress. Finally, having low physical and mental HRQoL was associated with lower weekly MVPA (-0.93 hours/week, 95% CI -1.19 to -0.66 and -0.39 hours/week, 95% CI -0.71 to -0.08 respectively vs moderate or high HRQoL).

CONCLUSIONS

We found that 40% of individuals with diabetes do not engage regularly in adequate physical activity. Comorbidities, higher BMI, higher perceived stress, and lower HRQoL were associated with less engagement in physical activity. This study suggests that subgroups of individuals with diabetes are at higher risk of physical inactivity.

Incident cardiovascular disease by clustering of favourable risk factors in type 1 diabetes: the EURODIAB Prospective Complications Study

AIMS

The aim of this prospective study was to examine CVD risk reduction in type 1 diabetes (1) for people with favourable cardiovascular health metrics and (2) by clustering of these metrics.

METHODS

Data from 2313 participants from the EURODIAB Prospective Complications Study were analysed. All had type 1 diabetes (51% men, mean ± SD age 32 ± 9 years). Seven cardiovascular health metrics were studied-smoking, BMI, physical activity, a diet score, total cholesterol/HDL-cholesterol ratio, combined systolic and diastolic BP and HbA_1c-divided into favourable/less favourable categories. Cox proportional hazards models were used to calculate HRs (95% CIs) of incident CVD for each metric. Clusters were made by scoring each individual by the number of favourable metrics.

RESULTS

A total of 163 people developed incident CVD during a mean ± SD follow-up of 7.2 ± 1.3 years. Participants with more favourable HbA_1c levels of <57 mmol/mol (<7.4%) had a 37% significantly lower CVD risk than those with a less favourable HbA_1c (HR [95% CI] 0.63 [0.44, 0.91]), and participants with a more favourable BP (systolic BP <112 mmHg and diastolic BP <70 mmHg) had a 44% significantly lower CVD risk than participants in the less favourable BP group (HR [95% CI] 0.56 [0.34, 0.92]). There was a dose-response relation with a lower HR observed with greater clustering of more favourable metrics: people with four or more favourable metrics had an HR of 0.37 (95% CI 0.18, 0.76), adjusted for sex and age at diabetes diagnosis, compared with those with no favourable metrics.

CONCLUSIONS/INTERPRETATION

Low HbA_1c and low BP were protective cardiovascular health metrics in our study of people with type 1 diabetes. Targeting all cardiovascular health metrics could be more effective in preventing CVD than targeting single metrics.

Protective effects of physical activity against health risks associated with type 1 diabetes: “Health benefits outweigh the risks”

The magnitude of diabetes mellitus (DM) has increased in recent decades, where the number of cases and the proportion of the disease have been gradually increasing over the past few decades. The chronic complications of DM affect many organ systems and account for the majority of morbidity and mortality associated with the disease. The prevalence of type 1 DM (T1DM) is increasing globally, and it has a very significant burden on countries and at an individual level. T1DM is a chronic illness that requires ongoing medical care and patient self-management to prevent complications. This study aims to discuss the health benefits of physical activity (PA) in T1DM patients. The present review article was performed following a comprehensive literature search. The search was conducted using the following electronic databases: “Cochrane Library”, Web of Science, PubMed, HINARI, EMBASE, Google for grey literature, Scopus, African journals Online, and Google Scholar for articles published up to June 21, 2021. The present review focused on the effects of PA on many outcomes such as blood glucose (BG) control, physical fitness, endothelial function, insulin sensitivity, well-being, the body defense system, blood lipid profile, insulin resistance, cardiovascular diseases (CVDs), insulin requirements, blood pressure (BP), and mortality. It was found that many studies recommended the use of PA for the effective management of T1DM. PA is a component of comprehensive lifestyle modifications, which is a significant approach for the management of T1DM. It provides several health benefits, such as improving BG control, physical fitness, endothelial function, insulin sensitivity, well-being, and the body defense system. Besides this, it reduces the blood lipid profile, insulin resistance, CVDs, insulin requirements, BP, and mortality. Overall, PA has significant and essential protective effects against the health risks associated with T1DM. Even though PA has several health benefits for patients with T1DM, these patients are not well engaged in PA due to barriers such as a fear of exercise-induced hypoglycemia in particular. However, several effective strategies have been identified to control exercise-induced hypoglycemia in these patients. Finally, the present review concludes that PA should be recommended for the management of patients with T1DM due to its significant health benefits and protective effects against associated health risks. It also provides suggestions for the future direction of research in this field.

Nitric oxide-dependent micro- and macrovascular dysfunction occurs early in adolescents with type 1 diabetes

Arterial stiffness and endothelial dysfunction are both reported in children with type 1 diabetes (DM1) and may predict future cardiovascular events. In health, nitric oxide (NO) relaxes arteries and increases microvascular perfusion. The relationships between NO-dependent macro- and microvascular functional responses and arterial stiffness have not been studied in adolescents with DM1. Here, we assessed macro- and microvascular function in DM1 adolescents and age-matched controls at baseline and during an oral glucose challenge (OGTT). DM1 adolescents (n = 16) and controls (n = 14) were studied before and during an OGTT. At baseline, we measured: 1) large artery stiffness using both aortic augmentation index (AI) and carotid-femoral pulse wave velocity (cfPWV); 2) brachial flow-mediated dilation (FMD) and forearm endothelial function using postischemic flow velocity (PIFV); and 3) forearm muscle microvascular blood volume (MBV) using contrast-enhanced ultrasound. Following OGTT, AI, cfPWV, and MBV were reassessed at 60 min and MBV again at 120 min. Within individual and between-group, comparisons were made by paired and unpaired t tests or repeated measures ANOVA. Baseline FMD was lower (P = 0.02) in DM1. PWV at 0 and 60 min did not differ between groups. Baseline AI did not differ between groups but declined with OGTT only in controls (P = 0.02) and was lower than DM1 at 60 min (P < 0.03). Baseline MBV was comparable in DM1 and control groups, but declined in DM1 at 120 min (P = 0.01) and was lower than the control group (P < 0.03). There was an inverse correlation between plasma glucose and MBV at 120 min (r = -0.523, P < 0.01). No differences were noted between groups for V̇O2max (mL/min/kg), body fat (%), or body mass index (BMI). NO-dependent macro- and microvascular function, including FMD and AI, and microvascular perfusion, respectively, are impaired early in the course of DM1, precede increases of arterial stiffness, and may provide an early indicator of vascular risk.NEW & NOTEWORTHY This is the first study to show that type 1 diabetes impairs multiple nitric oxide-dependent vascular functions.

Exercise and nutrition in type 1 diabetes: Insights from the FinnDiane cohort

Type 1 diabetes is a challenging disease, characterized by dynamic changes in the insulin need during life periods, seasons of the year, but also by everyday situations. In particular, changes in insulin need are evident before, during and after exercise and having meals. In the midst of different life demands, it can be very burdensome to achieve tight glycemic control to prevent late diabetes complications, and at the same time, to avoid hypoglycemia. Consequently, many individuals with type 1 diabetes are faced with diabetes distress, decreasing profoundly their quality of life. Today, the nationwide Finnish Diabetic Nephropathy (FinnDiane) Study, launched in 1997, has gathered data from more than 8,000 well-characterized individuals with type 1 diabetes, recruited from 93 centers all over Finland and has established its position as the world's leading project on studying complications in individuals with type 1 diabetes. Studying risk factors and mechanisms of diabetes complications is inconceivable without trying to understand the effects of exercise and nutrition on glycemic control and the development of diabetes complications. Therefore, in this paper we provide findings regarding food and exercise, accumulated during the 25 years of studying lives of Finnish people with type 1 diabetes.

Obesity in people living with type 1 diabetes

Although type 1 diabetes is traditionally considered a disease of lean people, overweight and obesity are becoming increasingly more common in individuals with type 1 diabetes. Non-physiological insulin replacement that causes peripheral hyperinsulinaemia, insulin profiles that do not match basal and mealtime insulin needs, defensive snacking to avoid hypoglycaemia, or a combination of these, are believed to affect body composition and drive excessive accumulation of body fat in people with type 1 diabetes. The consequences of overweight or obesity in people with type 1 diabetes are of particular concern, as they increase the risk of both diabetes-related and obesity-related complications, including cardiovascular disease, stroke, and various types of cancer. In this Review, we summarise the current understanding of the aetiology and consequences of excessive bodyweight in people with type 1 diabetes and highlight the need to optimise future prevention and treatment strategies in this population.

Adherence to physical activity recommendations and barriers to physical activity participation among adults with type 1 diabetes

Background

Physical activity (PA) is important for those with type 1 diabetes (T1DM); however, accurate information on PA in people with T1DM is limited.

Aims

This study assessed adherence to PA guidelines using both objective and subjective PA measures and evaluated the relationship between accelerometer-measured PA and cardiovascular disease (CVD) risk factors. Barriers to PA were also assessed.

Methods

Using an observational cross-sectional design, PA was measured objectively over 7 days in 72 participants (34 males) using an accelerometer (ActiGraph) and subjectively using the International Physical Activity Questionnaire (IPAQ). Perceived barriers to PA were assessed using the Barriers to Physical Activity in Diabetes (type 1) scale. Multiple linear regression models assessed the influence of PA on HbA1c and CVD risk factors.

Results

Mean age ± SD was 40.9 ± 12.9 years, diabetes duration was 18 ± 11.6 years, and HbA1c was 65 ± 14 mmol/mol /8.0 ± 1.3%. Twenty-three (32%) participants exercised according to PA recommendations as measured by an accelerometer. Sixty-nine (97%) participants reported meeting the recommendations as per the IPAQ. Those meeting recommendations (accelerometry) had a lower HbA1c (p = 0.001), BMI (p = 0.032), waist circumference (p = 0.006), and fat mass (p = 0.032) and a greater number of hypoglycaemic events (p = 0.004). Fear of hypoglycaemia was the strongest barrier to PA (mean 3.4 ± 2.0).

Conclusion

The majority of participants failed to meet PA recommendations. Meeting the recommendations was associated with healthier CVD risk factor profiles. Individuals with T1DM possibly overestimate their PA using self-reported measures and require support and education to safely improve activity levels.

Can Resistance Exercise Be a Tool for Healthy Aging in Post-Menopausal Women with Type 1 Diabetes?

Due to improvements in diabetes care, people with type 1 diabetes (T1D) are living longer. Studies show that post-menopausal T1D women have a substantially elevated cardiovascular risk compared to those without T1D. As T1D may also accelerate age-related bone and muscle loss, the risk of frailty may be considerable for T1D women. Exercise and physical activity may be optimal preventative therapies to maintain health and prevent complications in this population: They are associated with improvements in, or maintenance of, cardiovascular health, bone mineral density, and muscle mass in older adults. Resistance exercise, in particular, may provide important protection against age-related frailty, due to its specific effects on bone and muscle. Fear of hypoglycemia can be a barrier to exercise in those with T1D, and resistance exercise may cause less hypoglycemia than aerobic exercise. There are currently no exercise studies involving older, post-menopausal women with T1D. As such, it is unknown whether current guidelines for insulin adjustment/carbohydrate intake for activity are appropriate for this population. This review focuses on existing knowledge about exercise in older adults and considers potential future directions around resistance exercise as a therapeutic intervention for post-menopausal T1D women.

Fear of hypoglycemia, a game changer during physical activity in type 1 diabetes mellitus patients

Hypoglycemia limits optimal glycemic management of patients with type 1 diabetes mellitus (T1DM). Fear of hypoglycemia (FoH) is a significant psychosocial consequence that negatively impacts the willingness of T1DM patients to engage in and profit from the health benefits of regular physical activity (e.g., cardiometabolic health, improved body composition, cardiovascular fitness, quality of life). Technological advances, improved insulin regimens, and a better understanding of the physiology of various types of exercise could help ameliorate FoH. This narrative review summarizes the available literature on FoH in children and adults and tools to avoid it.

Association of neighborhood greenness exposure with cardiovascular diseases and biomarkers

AIM

Living in areas with neighborhood greenness may be associated with the incidence of cardiovascular diseases (CVDs). However, little evidence in this regard has emerged from developing countries. In the present study, we examined neighborhood greenness associated with CVDs and the lipid accumulation product (LAP) and pulse pressure (PP) in China.

METHODS

We undertook our analysis using a community cross-sectional survey conducted in Longzihu District of Bengbu from July to August 2015. We measured triglyceride levels, waist circumference, and blood pressure. To assess exposure to neighborhood greenness, we used the average normalized difference vegetation index (NDVI) at 1,000-, 1,500-, and 2,000-m buffers in the participant community. We employed generalized mixed models to determine the association among neighborhood greenness, CVDs, LAP, and PP. We conducted stratified analysis by age, gender, income, and education. We assessed the potential mediating effects of road proximity and physical activity on greenness and CVDs, PP, and LAP.

RESULTS

The highest tertiles of NDVI_1500-m were steadily and significantly associated with lower odds of CVDs prevalence: the adjusted OR of such prevalence was 0.612 (95% CI, 0.462-0.811); higher NDVI was significantly associated with lower PP levels. The NDVI was strongly associated with CVDs prevalence among participants who were male and had high income. Ambient road proximity significantly mediated 9.7% of the estimated association between greenness and PP, there was no evidence of mediation effects for physical activity.

CONCLUSIONS

Higher neighborhood greenness could have a beneficial effect on CVDs and biomarkers. There were higher associations between residential greenness and CVDs among male and higher-income individuals; road proximity partially mediated the observed association between greenness and PP.

The impact of pharmacological and lifestyle interventions on body weight in people with type 1 diabetes: A systematic review and meta-analysis

AIM

To systematically review the effects of pharmacological and lifestyle interventions on body weight as a secondary outcome in people with type 1 diabetes.

METHODS

The Ovid Medline, Embase and Cochrane Library databases were searched for relevant pharmacological (glucagon-like peptide-1 [GLP-1] receptor agonist, sodium-glucose co-transporter-2 [SGLT-2] inhibitor, dipeptidyl peptidase-4 [DPP-4] inhibitor and metformin) and lifestyle intervention studies (diet and exercise) for adults with type 1 diabetes reporting body weight change and HbA1c published from January 2000 to May 2020. Meta-analyses were performed for 16 randomized controlled trials (RCTs).

RESULTS

Thirty-three RCTs (n = 9344 participants), 26 pharmacological (on average 43.9 years, 83.1 kg, HbA1c 8.1%; 55.8% male) and seven lifestyle-based interventions (on average 37.0 years, 85.0 kg, HbA1c 8.1%; 84.6% male), were analysed. The GLP-1 receptor agonist liraglutide 0.6 mg (mean difference [MD]: -2.22 kg [95% CI: -2.55 to -1.90]), 1.2 mg (MD: -3.74 kg [95% CI: -4.16 to -3.33]) and 1.8 mg (MD: -4.85 kg [95% CI: -5.29 to -4.41]), and the SGLT-2 inhibitors empagliflozin 2.5 mg (MD: -1.47 kg [95% CI: -2.23 to -0.71]), 10 mg (MD: -2.77 kg [95% CI: -3.24 to -2.31]) and 25 mg (MD: -3.06 kg [95% CI: -3.57 to -2.55]) and sotagliflozin 200 mg (MD: -2.40 kg [95% CI: -2.87 to -1.94]) and 400 mg (MD: -3.23 [95% CI: -3.73 to -2.72]) were associated with significant reductions in body weight. No significant effect on body weight was found for DPP-4 inhibitors, other GLP-1-receptor agonists, metformin, or for lifestyle interventions (i.e. exercise and diet).

CONCLUSIONS

In people with type 1 diabetes, several adjuvant pharmacological interventions showed weight reduction as a secondary outcome. Future studies in overweight people with type 1 diabetes are needed to establish whether the lifestyle and pharmacological interventions reviewed here have potential as components of complex interventions aimed at body weight reduction as a primary outcome.

Development of a group structured education programme to support safe exercise in people with Type 1 diabetes: the EXTOD education programme

AIM

To develop a structured education programme for individuals with Type 1 diabetes who are engaging in regular exercise.

METHOD

A multidisciplinary team of experts in supporting exercise and physical activity for people with Type 1 diabetes, alongside researchers with experience of developing self-management education, developed an exercise programme using the Medical Research Council framework. The programme was informed by a review of the evidence relating to Type 1 diabetes and exercise, the behaviour change literature (including the behaviour change taxonomy), and qualitative interviews with stakeholders. The programme and supporting resources were refined using an iterative process of testing, delivery and collecting feedback from participants and the wider development team.

RESULTS

The outcome of the intervention development was the design of a feasible and acceptable intervention for people with Type 1 diabetes to support safe exercise. The pilot allowed refinement of the intervention prior to testing in a two-site feasibility randomized controlled trial. Key findings from the pilot informed minor restructuring of the timetable (timings and order) and adaptation of supporting educational materials (participant handbook and teaching materials).

CONCLUSION

The 'EXercise in people with Type One Diabetes' (EXTOD) education programme has been developed using robust methodology for the generation of educational interventions. It now needs testing in a randomized controlled trial.

Frequent physical activity is associated with reduced risk of severe diabetic retinopathy in type 1 diabetes

AIMS

The aim of this study was to investigate whether leisure-time physical activity (LTPA) is associated with the development of severe diabetic retinopathy in individuals with type 1 diabetes.

METHODS

Prospective observational analysis as part of the Finnish diabetic nephropathy (FinnDiane) Study with a mean follow-up time of 10.7 years was performed. A total of 1612 individuals with type 1 diabetes were recruited, and LTPA was assessed at baseline using a validated self-report questionnaire. Severe diabetic retinopathy was defined as the initiation of laser treatment due to severe nonproliferative, proliferative retinopathy or diabetic maculopathy (identified from the Care Register for Health Care).

RESULTS

A total of 261 patients received laser treatment during the follow-up. Higher frequency of LTPA was associated with a lower incidence of severe diabetic retinopathy (p = 0.024), a finding that remained significant after adjustment for gender, duration, age at onset of diabetes, kidney function, BMI, triglycerides and systolic blood pressure. However, when HbA_1c and smoking were added to the Cox regression model the association was no more significant.

CONCLUSIONS

Frequent LTPA is associated with a lower incidence of severe diabetic retinopathy during the follow-up. The total amount or the other components of LTPA (intensity or duration of a single session) were not associated with severe diabetic retinopathy.

The Athlete with Type 1 Diabetes: Transition from Case Reports to General Therapy Recommendations

Fear of hypoglycemia is a common barrier to exercise and physical activity for individuals with type 1 diabetes. While some of the earliest studies in this area involved only one or two participants, the link between exercise, exogenous insulin, and hypoglycemia was already clear, with the only suggested management strategies being to decrease insulin dosage and/or consume carbohydrates before and after exercise. Over the past 50 years, a great deal of knowledge has been developed around the impact of different types and intensities of exercise on blood glucose levels in this population. Recent decades have also seen the development of technologies such as continuous glucose monitors, faster-acting insulins and commercially available insulin pumps to allow for the real-time observation of interstitial glucose levels, and more precise adjustments to insulin dosage before, during and after activity. As such, there are now evidence-based exercise and physical activity guidelines for individuals with type 1 diabetes. While the risk of hypoglycemia has not been completely eliminated, therapy recommendations have evolved considerably. This review discusses the evolution of the knowledge and the technology related to type 1 diabetes and exercise that have allowed this evolution to take place.

Alcohol consumption or cigarette smoking and cardiovascular disease risk in youth with type 1 diabetes

AIM

To assess the association between alcohol consumption and/or cigarette smoking with other unhealthy behaviors and clinical cardiovascular risk factors in youth with type 1 diabetes.

METHODS

Two hundred and twenty-eight youth with type 1 diabetes (age 13-19 years) were consecutively enrolled in three Regional Pediatric Diabetes Centers in Italy. Demographic, anthropometric, lifestyle (adherence to the Mediterranean diet pattern and sports participation) and laboratory parameters were compared among youth reporting isolated or combined alcohol consumption and/or cigarette smoking.

RESULTS

Ten percent of the youth reported alcohol consumption, 10% cigarette smoking and 6% both alcohol and cigarette use; 74% did not report alcohol or cigarette use. Compared to non-drinker non-smoker youth, smokers showed significantly higher percentages of each of the behavioral and clinical cardiovascular risk factors. Drinkers showed a significantly higher proportion of abdominal adiposity, dyslipidemia and poor adherence to the Mediterranean diet. Alcohol consumption was independently associated with both dyslipidemia and high glycosylated hemoglobin.

CONCLUSIONS

Our findings emphasize the need to increase the awareness of youth with T1D about the negative impact of alcohol drinking on cardiovascular risk, since the effects of alcohol might be underestimated with respect to the well-known detrimental effects of smoking. Clustering of unhealthy lifestyle should be discouraged in type 1 diabetes youth in order to promote cardiovascular protection.

A Multidisciplinary Evaluation of a Virtually Supervised Home-Based High-Intensity Interval Training Intervention in People With Type 1 Diabetes

OBJECTIVE

Adopt a multidisciplinary approach to evaluate a virtually supervised home-based high-intensity interval training (Home-HIT) intervention in people with type 1 diabetes.

RESEARCH DESIGN AND METHODS

Eleven individuals with type 1 diabetes (seven women; age 30 ± 3 years; [Formula: see text] 2.5 ± 0.2 L/min; duration of diabetes 10 ± 2 years) completed 6 weeks of Home-HIT. A heart rate monitor and mobile phone application were used to provide feedback to the participants and research team on exercise intensity (compliance) and adherence.

RESULTS

Training adherence was 95 ± 2%, and compliance was 99 ± 1%. Home-HIT increased [Formula: see text] by 7% (P = 0.017) and decreased insulin dose by 13% (P = 0.012). Blood glucose concentration did not change from baseline to immediately or 1 h post Home-HIT. Qualitative perceptions of Home-HIT and the virtual-monitoring system were positive, supporting that the intervention successfully removed exercise barriers in people with type 1 diabetes.

CONCLUSIONS

Virtually monitored Home-HIT resulted in high adherence alongside increased [Formula: see text] and decreased insulin dose.

Home-based high-intensity interval training reduces barriers to exercise in people with type 1 diabetes

NEW FINDINGS

What is the topic of this review? This symposium review provides an overview of the recent work investigating whether a virtually monitored home-based high-intensity interval training (Home-HIT) intervention reduces the fear of hypoglycaemia and other common barriers to exercise in people with type 1 diabetes. What advances does it highlight? Home-HIT seems to offer a strategy to reduce fear of hypoglycaemia, while simultaneously removing other known barriers that prevent people with type 1 diabetes from taking up exercise, because it is time efficient, requires no travel time or costs associated with gym memberships, and allows people to exercise in their chosen environment.

ABSTRACT

People with type 1 diabetes (T1D) are recommended to engage in regular exercise for a variety of health and fitness reasons. However, many lead a sedentary lifestyle and fail to meet the physical activity guidelines, in part because of the challenge of managing blood glucose concentration and fear of hypoglycaemia. A number of strategies designed to help people with T1D to manage their blood glucose during and after exercise have been investigated. Although many of these strategies show promise in facilitating blood glucose management during and after exercise, they do not target the many other common barriers to exercise that people with T1D face, such as difficulty with cost and travel time to gyms, limited access to exercise bikes and treadmills, and a possible dislike of exercising in front of others in public places. In this symposium review, we provide an overview of ongoing research into a virtually monitored home-based high-intensity interval training (Home-HIT) programme that is designed to reduce these other common barriers to exercise. The conclusion of this review is that Home-HIT seems to offer a strategy to reduce fear of hypoglycaemia, while simultaneously removing other known barriers preventing people with T1D from taking up exercise, such as being time efficient, requiring no travel time or costs associated with gym memberships, and giving them the opportunity to exercise in their chosen environment, reducing the embarrassment experienced by some when exercising in public.

Timing of insulin basal rate reduction to reduce hypoglycemia during late post-prandial exercise in adults with type 1 diabetes using insulin pump therapy: A randomized crossover trial

AIMS

To compare the efficacy of three timings to decrease basal insulin infusion rate to reduce exercise-induced hypoglycaemia in patients with type 1 diabetes (T1D) using pump therapy.

METHODS

A single-blinded, randomized, 3-way crossover study in 22 adults that had T1D > 1 year and using insulin pump > 3 months (age, 40 ± 15 years; HbA_1c, 56.3 ± 10.2 mmol/mol). Participants practiced three 45-min exercise sessions (ergocyle) at 60% VO_2peak 3 hours after lunch comparing an 80% reduction of basal insulin applied 40 minutes before (T-40), 20 minutes before (T-20) or at exercise onset (T0).

RESULTS

No significant difference was observed for percentage of time spent < 4.0 mmol/L (T-40: 16 ± 25%; T-20: 26 ± 27%; T0: 24 ± 29%) (main outcome) and time spent in target range 4.0-10.0 mmol/L (T-40: 63 ± 37%; T-20: 66 ± 25%; T0: 65 ± 31%). With T-40 strategy, although not significant, starting blood glucose (BG) was higher (T-40: 8.6 ± 3.6 mmol/L; T-20: 7.4 ± 2.5 mmol/L ; T0: 7.4 ± 2.7 mmol/L), fewer patients needed extra carbohydrates consumption prior to exercise for BG < 5.0 mmol/L (T-40: n = 3; T-20: n = 5; T0: n = 6) as well as during exercise for BG < 3.3 mmol/L [T-40: n = 6 (27%); T-20: n = 12 (55%); T0: n = 11 (50%)] while time to first hypoglycaemic episode was delayed (T-40: 28 ± 14 min; T-20: 24 ± 10 min; T0: 22 ± 11 min).

CONCLUSION

Decreasing basal insulin infusion rate by 80% up to 40 minutes before exercise onset is insufficient to reduce exercise-induced hypoglycaemia.

Carbohydrate Restriction in Type 1 Diabetes: A Realistic Therapy for Improved Glycaemic Control and Athletic Performance?

Around 80% of individuals with Type 1 diabetes (T1D) in the United States do not achieve glycaemic targets and the prevalence of comorbidities suggests that novel therapeutic strategies, including lifestyle modification, are needed. Current nutrition guidelines suggest a flexible approach to carbohydrate intake matched with intensive insulin therapy. These guidelines are designed to facilitate greater freedom around nutritional choices but they may lead to higher caloric intakes and potentially unhealthy eating patterns that are contributing to the high prevalence of obesity and metabolic syndrome in people with T1D. Low carbohydrate diets (LCD; <130 g/day) may represent a means to improve glycaemic control and metabolic health in people with T1D. Regular recreational exercise or achieving a high level of athletic performance is important for many living with T1D. Research conducted on people without T1D suggests that training with reduced carbohydrate availability (often termed "train low") enhances metabolic adaptation compared to training with normal or high carbohydrate availability. However, these "train low" practices have not been tested in athletes with T1D. This review aims to investigate the known pros and cons of LCDs as a potentially effective, achievable, and safe therapy to improve glycaemic control and metabolic health in people with T1D. Secondly, we discuss the potential for low, restricted, or periodised carbohydrate diets in athletes with T1D.

Effects of Moderate Cycling Exercise on Blood Glucose Regulation Following Successful Clinical Islet Transplantation

CONTEXT

Islet transplantation is effective in preventing hypoglycemia in patients with type 1 diabetes (T1D). However, it is unknown whether transplanted islets regulate plasma glucose concentrations appropriately during and after exercise in human islet transplant recipient (ITxs).

OBJECTIVE

To determine the effect of exercise on plasma glucose, insulin, and glucagon concentrations in ITxs compared with control subjects (CONs) without diabetes.

INTERVENTION

Participants completed two conditions in random order: 45 minutes of aerobic exercise (60% VO2peak) and 45 minutes of seated rest. Blood samples were drawn at baseline, immediately after exercise or rest, and every 15 minutes throughout a 60-minute recovery period. Postexercise (24 hours) interstitial glucose was monitored with continuous glucose monitoring (CGM).

RESULTS

Twenty-four participants (12 ITxs, 12 CONs) completed the protocol. Plasma glucose decreased more over time with exercise in ITxs compared with CONs [main effects of treatment (P = 0.019), time (P = 0.001), and group (P = 0.012)]. Plasma glucose was lower during exercise vs rest in ITxs but not CONs [treatment by group interaction (P = 0.028)]. Plasma glucose decreased more during exercise than during rest [treatment by time interaction (P = 0.001)]. One ITx and one CON experienced plasma glucose concentrations <3.5 mmol/L at the end of exercise, both of whom returned above that threshold within 15 minutes. Nocturnal CGM glucose <3.5 mmol/L was detected in two CONs but no ITxs.

CONCLUSION

Despite a greater plasma glucose decline during exercise in ITxs, hypoglycemia risk was similar during and after exercise in ITxs compared with CONs.

Objective Measurement of Physical Activity in Adults With Newly Diagnosed Type 1 Diabetes and Healthy Individuals

Aims: Physical activity (PA) has many benefits in type 1 diabetes mellitus (type 1 DM). However, PA levels in people with type 1 DM have not previously been measured accurately. We aimed to compare objectively measured PA in adults recently diagnosed with type 1 DM and healthy adults.

Methods: Accelerometer data from 65 healthy adults [mean (SD) age 31 (13), 29% men] were compared with data from 50 people with type 1 DM [mean (SD) age 33 (10), 64% men], time since diagnosis <3months, HbA1c 76 ± 25 mmol/mol) in the EXTOD (Exercise for Type 1 Diabetes) pilot study. Briefly, EXTOD investigated the feasibility of recruiting recently diagnosed adults with type 1 DM into a yearlong exercise intervention. Multiple-regression models were used to investigate the association between diabetes status and activity outcomes.

Results: Adults recently diagnosed with type 1 DM spent on average a quarter less time in moderate-to-vigorous-physical-activity (MVPA) per day than healthy adults [after adjusting for confounders, predicted values: type 1 DM adults: [mean (SD)] 37.4 mins/day (9.1) Healthy adults: 52.9 mins/day (11.0)]. No difference in MVPA between the groups was seen at the weekend, but adults with type 1 DM spent more time in light physical activity (LPA), and less time in sedentary behavior. Time spent in sedentary or LPA during weekdays did not differ between groups.

Summary: Adults recently diagnosed with type 1 DM do less MVPA. Health care workers should encourage these people to engage in more PA. Further studies are needed to assess PA in people with type 1 DM of longer duration.

Clinical outcomes to exercise training in type 1 diabetes: A systematic review and meta-analysis

AIMS

To establish the relationship between exercise training and clinical outcomes in people with type I diabetes.

METHODS

Studies were identified through a MEDLINE search strategy, Cochrane Controlled Trials Registry, CINAHL, SPORTDiscus and Science Citation Index. The search strategy included a mix of key concepts related to trials of exercise training in people with type 1 diabetes; glycaemic control. Searches were limited to prospective randomized or controlled trials of exercise training in humans with type 1 diabetes lasting 12  weeks or more.

RESULTS

In exercised adults there were significant improvements in body mass Mean Difference (MD): -2.20 kg, 95% Confidence Interval (CI) -3.79-0.61, p = .007; body mass index (BMI) MD: -0.39 kg/m², 95% CI -0.75-0.02, p = .04; Peak VO₂ MD: 4.08 ml/kg/min, 95% CI -2.18-5.98, p < .0001; and, low-density lipoprotein cholesterol (LDL) MD: -0.21 mmol/L, 95% CI -0.33-0.08, p = .002. In exercised children there were significant improvements in insulin dose MD: -0.23 IU/kg, 95% CI -0.37-0.09, p = .002; waist circumference MD: -5.40 cm, 95% CI -8.45 to -2.35, p = .0005; LDL MD: -0.31 mmol/L, 95% CI -0.55 to -0.06, p = .02; and, triglycerides MD: -0.21 mmol/L, 95% CI -0.42 to -0.01, p = .04. There were no significant changes in glycosylated haemoglobin (HbA1C%), fasting blood glucose, resting heart rate, resting systolic blood pressure or high density lipoproteins in either group.

CONCLUSIONS

Exercise training improves some markers of type 1 diabetes severity; particularly body mass, BMI, Peak VO₂ and LDL in adults and insulin dose, waist circumference, LDL and triglycerides in children.

Emerging roles of SGLT2 inhibitors in obesity and insulin resistance: Focus on fat browning and macrophage polarization

Obesity-associated low-grade inflammation underlies insulin resistance and associated metabolic comorbidities, such as type 2 diabetes (T2D) and nonalcoholic fatty liver disease. Excessive ectopic fat deposition in obesity causes disorders of energy homeostasis and low-grade chronic inflammation in metabolic tissues. In particular, obesity-induced recruitment and activation of adipose tissue macrophages play a key role in the pathogenesis of insulin resistance and T2D. Therefore, treatment options for energy metabolism and macrophage polarization in obese subjects are needed. Sodium-glucose cotransporter (SGLT) 2 inhibitors increase urinary glucose excretion by inhibiting renal glucose reabsorption, thereby having subsequent anti-hyperglycemic effects and reducing body weight. We recently reported that the SGLT2 inhibitor empagliflozin increases fat utilization and browning in white adipose tissue and attenuates obesity-induced inflammation and insulin resistance by activating M2 macrophages. Thus, this review focuses on the beneficial effects of empagliflozin in energy homeostasis and obesity-related inflammation and insulin resistance.

Attitudes and barriers to exercise in adults with a recent diagnosis of type 1 diabetes: a qualitative study of participants in the Exercise for Type 1 Diabetes (EXTOD) study

OBJECTIVES

To explore attitudes and barriers to exercise in adults with new-onset type 1 diabetes mellitus (T1DM).

DESIGN

Qualitative methodology using focus group (n=1), individual face-to-face (n=4) and telephone interviews (n=8). Thematic analysis using the Framework Method.

SETTING

Nineteen UK hospital sites.

PARTICIPANTS

Fifteen participants in the Exercise for Type 1 Diabetes study. We explored current and past levels of exercise, understanding of exercise and exercise guidelines, barriers to increasing exercise levels and preferences for monitoring of activity in a trial.

RESULTS

Five main themes were identified: existing attitudes to exercise, feelings about diagnosis, perceptions about exercise consequences, barriers to increasing exercise and confidence in managing blood glucose. An important finding was that around half the participants reported a reduction in activity levels around diagnosis. Although exercise was felt to positively impact on health, some participants were not sure about the benefits or concerned about potential harms such as hypoglycaemia. Some participants reported being advised by healthcare practitioners (HCPs) not to exercise.

CONCLUSIONS

Exercise should be encouraged (not discouraged) from diagnosis, as patients may be more amenable to lifestyle change. Standard advice on exercise and T1DM needs to be made available to HCPs and patients with T1DM to improve patients' confidence in managing their diabetes around exercise.

TRIAL REGISTRATION NUMBER

ISRCTN91388505; Results.

Physical Activity Reduces Risk of Premature Mortality in Patients With Type 1 Diabetes With and Without Kidney Disease

OBJECTIVE

The aims of the study were to assess how baseline leisure-time physical activity (LTPA) and its exercise components intensity, duration, and frequency are associated with all-cause and cardiovascular mortality in patients with type 1 diabetes 1) overall, 2) stratified by presence or absence of chronic kidney disease (CKD), and 3) stratified by sex.

RESEARCH DESIGN AND METHODS

The study design was prospective and observational and included 2,639 patients with type 1 diabetes from the ongoing nationwide multicenter Finnish Diabetic Nephropathy (FinnDiane) Study. Mean follow-up time was 11.4 ± 3.5 years. LTPA was assessed by using a validated self-report questionnaire. Three hundred ten patients (11.7%) had CKD defined as an estimated glomerular filtration rate of ≤60 mL/min/1.73 m².

RESULTS

During follow-up, 270 deaths occurred. LTPA and all its components were associated with all-cause mortality, even after adjustment for the potential confounders sex, diabetic nephropathy, duration of diabetes, age at onset of diabetes, systolic blood pressure, triglycerides, BMI, and HbA_1c. Only exercise intensity was associated with cardiovascular mortality after adjustment for the confounders. Of the patients with CKD, 127 died during follow-up. The total amount of LTPA and exercise frequency were independently associated with lower risk of all-cause mortality when adjusted for covariates.

CONCLUSIONS

Exercise is associated with a lower risk of premature all-cause and cardiovascular mortality in patients with type 1 diabetes. This study also demonstrates that physical activity is associated with a lower risk of mortality in patients with type 1 diabetes and CKD.

One-year unsupervised individualized exercise training intervention enhances cardiorespiratory fitness but not muscle deoxygenation or glycemic control in adults with type 1 diabetes

Adaptations to long-term exercise training in type 1 diabetes are sparsely studied. We examined the effects of a 1-year individualized training intervention on cardiorespiratory fitness, exercise-induced active muscle deoxygenation, and glycemic control in adults with and without type 1 diabetes. Eight men with type 1 diabetes (T1D) and 8 healthy men (CON) matched for age, anthropometry, and peak pulmonary O₂ uptake, completed a 1-year individualized training intervention in an unsupervised real-world setting. Before and after the intervention, the subjects performed a maximal incremental cycling test, during which alveolar gas exchange (volume turbine and mass spectrometry) and relative concentration changes in active leg muscle deoxygenated (Δ[HHb]) and total (Δ[tHb]) hemoglobin (near-infrared spectroscopy) were monitored. Peak O₂ pulse, reflecting peak stroke volume, was calculated (peak pulmonary O₂ uptake/peak heart rate). Glycemic control (glycosylated hemoglobin A_1c (HbA_1c)) was evaluated. Both T1D and CON averagely performed 1 resistance-training and 3-4 endurance-training sessions per week (∼1 h/session at ∼moderate intensity). Training increased peak pulmonary O₂ uptake in T1D (p = 0.004) and CON (p = 0.045) (group × time p = 0.677). Peak O₂ pulse also rose in T1D (p = 0.032) and CON (p = 0.018) (group × time p = 0.880). Training increased leg Δ[HHb] at peak exercise in CON (p = 0.039) but not in T1D (group × time p = 0.052), while no changes in leg Δ[tHb] at any work rate were observed in either group (p > 0.05). HbA_1c retained unchanged in T1D (from 58 ± 10 to 59 ± 11 mmol/mol, p = 0.609). In conclusion, 1-year adherence to exercise training enhanced cardiorespiratory fitness similarly in T1D and CON but had no effect on active muscle deoxygenation or glycemic control in T1D.

Exercise to preserve β-cell function in recent-onset Type 1 diabetes mellitus (EXTOD) - a randomized controlled pilot trial

AIM

Residual β-cell function is present at the time of diagnosis with Type 1 diabetes. Preserving this β-cell function reduces complications. We hypothesized that exercise preserves β-cell function in Type 1 diabetes and undertook a pilot trial to address the key uncertainties in designing a definitive trial to test this hypothesis.

METHODS

A randomized controlled pilot trial in adults aged 16-60 years diagnosed with Type 1 diabetes within the previous 3 months was undertaken. Participants were assigned to control (usual care) or intervention (exercise consultation every month), in a 1 : 1 ratio for 12 months. The primary outcomes were recruitment rate, drop out, exercise adherence [weeks with ≥ 150 min of self-reported moderate to vigorous physical activity (MVPA)], and exercise uptake in the control group. The secondary outcomes were differences in insulin sensitivity and rate of loss of β-cell function between intervention and control at 6 and 12 months.

RESULTS

Of 507 individuals who were approached, 58 (28 control, 30 intervention) entered the study and 41 completed it. Participants were largely white European males, BMI 24.8 ± 3.8 kg/m² , HbA_1c 75 ± 25 mmol/mol (9 ± 2%). Mean level of objectively measured MVPA increased in the intervention group (mean 243 to 273 min/week) and 61% of intervention participants reached the target of ≥ 150 min/week of self-reported MVPA on at least 42 weeks of the year. Physical activity levels fell slightly in the control group (mean 277 to 235 min of MVPA/week). There was exploratory evidence that intervention group became more insulin sensitive and required less insulin. However, the rate of loss of β-cell function appeared similar between the groups, although the change in insulin sensitivity may have affected this.

CONCLUSION

We show that it is possible to recruit and randomize people with newly diagnosed Type 1 diabetes to a trial of an exercise intervention, and increase and maintain their exercise levels for 12 months. Future trials need to incorporate measures of greater adherence to exercise training targets, and include more appropriate measures of β-cell function. (Clinical Trials Registry No; ISRCTN91388505).

Are We Compensating for the Lack of Physical Activity in Our Diabetic Patients with Treatment Intensification?

Background: We studied the association between leisure time physical activity (LTPA) and glycemic control, body mass index (BMI), and hypoglycemic incidents in type 1 (T1DM) and type 2 diabetes patients (T2DM). Methods: This is a cross-sectional study of 198 diabetic patients (60 with type 1 diabetes, 138 with type 2 diabetes). LTPA was assessed by a validated 12-month questionnaire. Patients were grouped as sedentary and moderately to vigorously active. Outcome measures were Hemoglobin A1c (HbA1c), BMI, and hypoglycemic episodes. Results: LTPA effect on the HbA1c reduction was present in diabetes type 1 patients. Patients who were involved in the moderate to vigorous-intensity physical activity had a greater decrease in the HbA1c (p = 0.048) than patients with low physical activity (p = 0.085). Level of LTPA was neither associated with increased number of hypoglycemic episodes, nor BMI. After an average of 4 years of diabetes, the number of patients requiring more than one antidiabetic agent increased, although the observed difference did not correlate with LTPA level. Conclusions: LTPA has an influence on the regulation of diabetes type 1, and intensification of medical treatment is compensating for the lack of lifestyle change—especially in type 2 diabetics.

Frequent and intensive physical activity reduces risk of cardiovascular events in type 1 diabetes

AIMS/HYPOTHESIS

Cardiovascular disease (CVD) is the most common cause of premature death and disability among patients with type 1 diabetes. Diabetic nephropathy accounts for the increased cardiovascular morbidity and mortality of these patients. We recently showed that the intensity of exercise predicts the incidence and progression of diabetic nephropathy in patients with type 1 diabetes. Little is known about the relationship between physical activity and CVD. Therefore, we studied how physical activity affects the risk of CVD events in patients with type 1 diabetes.

METHODS

A 10 year follow-up study including 2180 type 1 diabetes patients from the nationwide multicentre Finnish Diabetic Nephropathy Study (FinnDiane). Leisure time physical activity (LTPA) was assessed by a previously validated self-report questionnaire. A CVD event was defined as a verified myocardial infarction, coronary procedure or stroke. Patients were analysed separately for the risk of developing a first ever CVD event and for the risk of a recurrent CVD event following a baseline event.

RESULTS

A total of 206 patients had an incident CVD event during follow-up. A higher total LTPA and higher intensity, frequency and duration of activity were associated with a lower risk of incident CVD events. The observed association between exercise frequency and incident CVD remained significant when adjusted for classic risk factors. Exercise intensity also had a borderline effect on the recurrence-free time in patients with a major CVD event at baseline.

CONCLUSIONS/INTERPRETATION

This study suggests that exercise, particularly high frequency and high intensity exercise, may reduce the risk of CVD events in patients with type 1 diabetes.

Efficacy of single-hormone and dual-hormone artificial pancreas during continuous and interval exercise in adult patients with type 1 diabetes: randomised controlled crossover trial

AIMS/HYPOTHESIS

The aim of this study was to assess whether the dual-hormone (insulin and glucagon) artificial pancreas reduces hypoglycaemia compared with the single-hormone (insulin alone) artificial pancreas during two types of exercise.

METHODS

An open-label randomised crossover study comparing both systems in 17 adults with type 1 diabetes (age, 37.2 ± 13.6 years; HbA_1c, 8.0 ± 1.0% [63.9 ± 10.2 mmol/mol]) during two exercise types on an ergocycle and matched for energy expenditure: continuous (60% [Formula: see text] for 60 min) and interval (2 min alternating periods at 85% and 50% [Formula: see text] for 40 min, with two 10 min periods at 45% [Formula: see text] at the start and end of the session). Blocked randomisation (size of four) with a 1:1:1:1 allocation ratio was computer generated. The artificial pancreas was applied from 15:30 hours until 19:30 hours; exercise was started at 18:00 hours and announced 20 min earlier to the systems. The study was conducted at the Institut de recherches cliniques de Montréal.

RESULTS

During single-hormone control compared with dual-hormone control, exercise-induced hypoglycaemia (plasma glucose <3.3 mmol/l with symptoms or <3.0 mmol/l regardless of symptoms) was observed in four (23.5%) vs two (11.8%) interventions (p = 0.5) for continuous exercise and in six (40%) vs one (6.25%) intervention (p = 0.07) for interval exercise. For the pooled analysis (single vs dual hormone), the median (interquartile range) percentage time spent at glucose levels below 4.0 mmol/l was 11% (0.0-46.7%) vs 0% (0-0%; p = 0.0001) and at glucose levels between 4.0 and 10.0 mmol/l was 71.4% (53.2-100%) vs 100% (100-100%; p = 0.003). Higher doses of glucagon were needed during continuous (0.126 ± 0.057 mg) than during interval exercise (0.093 ± 0.068 mg) (p = 0.03), with no reported side-effects in all interventions.

CONCLUSIONS/INTERPRETATION

The dual-hormone artificial pancreas outperformed the single-hormone artificial pancreas in regulating glucose levels during announced exercise in adults with type 1 diabetes.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01930110 FUNDING: : Société Francophone du Diabète and Diabète Québec.

Review of cardiometabolic risk factors in a cohort of paediatric type 1 diabetes mellitus patients

BACKGROUND

Type 1 diabetes mellitus (T1DM) is a recognised risk factor for cardiometabolic disease. Other risk factors include age, gender, family history, glycaemic control, dyslipidaemia, weight, and activity levels.

AIMS

To estimate the point prevalence of cardiometabolic risk factors in a paediatric population with T1DM.

METHODS

Eighty-one patients with T1DM aged between 10 and 16 years attended during the study and 56 (69.1 %) patients agreed to participate. Mixed methods data collection included a questionnaire developed for this study, supplemented by retrospective and prospective data collected from the patient records.

RESULTS

Of 56 subjects with T1DM, aged 12.7 ± 1.7 years (10-16 years) 26 were male and 30 were female. Mean HbA1c was 72 ± 14 mmol/mol. 53 subjects (94.6 %) had at least one additional cardiometabolic risk factor.

CONCLUSIONS

Cardiometabolic risk factors are present in this population with T1DM. Identifying cardiometabolic risk factors in adolescent T1DM patients is the first step in prevention of future morbidity and mortality.

Physical Activity in Adults With Type 1 Diabetes

PURPOSE

The purpose of this study was to examine sociodemographic, clinical, and psychological factors associated with engaging in regular physical activity (PA) in adults with type 1 diabetes.

METHODS

Secondary cross-sectional analysis based on data from the Type One Diabetes Exchange clinic registry was conducted. Adults ≥18 years old enrolled in the clinic registry who had completed PA self-report data (n = 7153) were included in this study.

RESULTS

Mean age was 37.14 ± 17 years, and 54% (n = 3840) were men. Type 1 diabetes duration was 19.5 ± 13.5 years, and mean A1C level was 7.9% ± 1.5% (62 mmol/mol). Twelve percent (n = 848) of the sample reported no PA; 55% (n = 3928) reported PA 1 to 4 days per week; and 33% (n = 2377) reported PA ≥5 days per week. Factors that were associated with increased odds of no PA were older age, less-than-excellent general health, increased body mass index, longer duration of diabetes, and increased depressive symptoms. More blood glucose meter checks per day decreased odds of no PA. Factors associated with lower odds of ≥5 days of PA included minority race/ethnicity, education, less-than-excellent general health, presence of a foot ulcer, increased body mass index, and depressive symptoms. Male sex, less-than-full-time employment, and being single increased the odds of ≥5 days of PA.

CONCLUSIONS

Several demographic, clinical, diabetes-related, and psychosocial factors were related to PA. Potential interventions may target those with depressive symptoms or self-reported poor general health, or they may be tailored to working adults who may find it harder to be physically active.

Cardiovascular disease and type 1 diabetes: prevalence, prediction and management in an ageing population

Cardiovascular disease (CVD) is a major cause of mortality in type 1 diabetes mellitus (T1D). However, evidence of its risks and management is often extrapolated from studies in type 2 diabetic (T2D) patients or the general population. This approach is unsatisfactory given that the underlying pathology, demographics and natural history of the disease differ between T1D and T2D. Furthermore, with a rising life expectancy, a greater number of T1D patients are exposed to the cardiovascular (CV) risk factors associated with an ageing population. The aim of this review is to examine the existing literature around CVD in T1D. We pay particular attention to CVD prevalence, how well we manage risk, potential biomarkers, and whether the studies included the older aged patients (defined as aged over 65). We also discuss approaches to the management of CV risk in the older aged. The available data suggest a significant CVD burden in patients with T1D and poor management of CV risk factors. This is underpinned by a poor evidence base for therapeutic management of CV risk specifically for patients with T1D, and in the most relevant population - the older aged patients. We would suggest that important areas remain to be addressed, particularly exploring the risks and benefits of therapeutic approaches to CVD management in the older aged.

Association of diet and lifestyle with glycated haemoglobin in type 1 diabetes participants in the EURODIAB prospective complications study

BACKGROUND/OBJECTIVES

Diet and lifestyle advice for type 1 diabetes (T1DM) patients is based on little evidence and putative effects on glycaemic control. Therefore, we investigated the longitudinal relation between dietary and lifestyle variables and HbA1c levels in patients with type 1 diabetes.

SUBJECTS/METHODS

A 7-year prospective cohort analysis was performed in 1659 T1DM patients (52% males, mean age 32.5 years) participating in the EURODIAB Prospective Complications Study. Baseline dietary intake was assessed by 3- day records and physical activity, smoking status and alcohol intake by questionnaires. HbA1c during follow-up was centrally assessed by immunoassay. Analysis of variance (ANOVA) and restricted cubic spline regression analyses were performed to assess dose-response associations between diet and lifestyle variables and HbA1c levels, adjusted for age, sex, lifestyle and body composition measures, baseline HbA1c, medication use and severe hypoglycaemic attacks.

RESULTS

Mean follow-up of our study population was 6.8 (s.d. 0.6) years. Mean HbA1c level was 8.25% (s.d. 1.85) (or 66.6 mmol/mol) at baseline and 8.27% (s.d. 1.44) at follow-up. Physical activity, smoking status and alcohol intake were not associated with HbA1c at follow-up in multivariable ANOVA models. Baseline intake below the median of vegetable protein (<29 g/day) and dietary fibre (<18 g/day) was associated with higher HbA1c levels. Restricted cubic splines showed nonlinear associations with HbA1c levels for vegetable protein (P (nonlinear)=0.008) and total dietary fibre (P (nonlinear)=0.0009).

CONCLUSIONS

This study suggests that low intake of vegetable protein and dietary fibre are associated with worse glycaemic control in type 1 diabetes.

Low 25-hydroxyvitamin D2 and 25-hydroxyvitamin D3 levels are independently associated with macroalbuminuria, but not with retinopathy and macrovascular disease in type 1 diabetes: the EURODIAB prospective complications study

Background

Low circulating levels of total vitamin D [25(OH)D] and 25(OH)D₃ have been associated with vascular complications in few studies on individuals with type 1 diabetes. However, these measures are affected by UV light exposure. Circulating 25(OH)D₂, however, solely represents dietary intake of vitamin D₂, but its association with complications of diabetes is currently unknown. We investigated the associations between 25(OH)D₂ and 25(OH)D₃ and the prevalence of albuminuria, retinopathy and cardiovascular disease (CVD) in individuals with type 1 diabetes.

Methods

We measured circulating 25(OH)D₂ and 25(OH)D₃ in 532 individuals (40 ± 10 years old, 51 % men) with type 1 diabetes who participated in the EURODIAB Prospective Complications Study. Cross-sectional associations of 25(OH)D₂ and 25(OH)D₃ with albuminuria, retinopathy and CVD were assessed with multiple logistic regression analyses adjusted for age, sex, season, BMI, smoking, HbA_1c, total-HDL-cholesterol-ratio, systolic blood pressure, antihypertensive medication, eGFR, physical activity, alcohol intake, albuminuria, retinopathy and CVD, as appropriate.

Results

Fully adjusted models revealed that 1 nmol/L higher 25(OH)D₂ and 10 nmol/L higher 25(OH)D₃ were associated with lower prevalence of macroalbuminuria with ORs (95 % CI) of 0.56 (0.43;0.74) and 0.82 (0.72;0.94), respectively. These vitamin D species were not independently associated with microalbuminuria, non-proliferative and proliferative retinopathy or CVD.

Conclusions

In individuals with type 1 diabetes, both higher 25(OH)D₂ and 25(OH)D₃ are associated with a lower prevalence of macroalbuminuria, but not of retinopathy and CVD. Prospective studies are needed to further examine the associations between 25(OH)D₂ and 25(OH)D₃ and the development of microvascular complications and CVD in type 1 diabetes.

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-015-0231-2) contains supplementary material, which is available to authorized users.

Effects of Organized Physical Activity on Selected Health Indices among Women Older than 55 Years

The main aim of this study was to determine health benefits among women older than 55 years who participated in organized, group-based physical activity (OPA). Thirty-five women aged 65.0 ± 7.3 years volunteered for this study. The classical and nonclassical cardiovascular (CVD) risk factors were measured before and after a 2-week OPA camp in a remote location and 3 months of OPA. Self-guided physical activity was analyzed 18 months after OPA. Two-week effects included significant decreases in body mass index, waist and hip circumferences, resting systolic and diastolic blood pressure (BP) and resting heart rate, improved exercise capacity (EC), improved low-density lipoprotein and high-density lipoprotein (HDL-C), cholesterol, and other atherogenic lipid indices (ALI), and a reduction in 10-year estimated risk of death from CVD. Three-month effects included a further decrease in systolic BP, improvements in EC and HDL-C, and maintenance of lower levels of ALI, as well as lower CVD risk. The implementation of the OPA programme had a positive impact on somatic features, exercise capacity, biochemical indices, and risk for death from CVD. The presented programme can be regarded as an effective element of primary prevention of cardiovascular diseases among women older than 55 years.

Exercise strategies for hypoglycemia prevention in individuals with type 1 diabetes

IN BRIEF Fear of hypoglycemia is one of the main barriers to physical activity for individuals with type 1 diabetes. Recent studies indicate that anaerobic forms of exercise (i.e., resistance exercise/weight lifting, sprints, and high-intensity intervals) can attenuate exercise-related declines in blood glucose both during and after exercise in young, healthy adults with type 1 diabetes. These responses might vary based on age, sex, and fitness level and in the general safety of relying on them to prevent hypoglycemia.

The time has come to test the beta cell preserving effects of exercise in patients with new onset type 1 diabetes

Type 1 diabetes is characterised by immune-mediated destruction of insulin-producing beta cells. Significant beta cell function is usually present at the time of diagnosis with type 1 diabetes, and preservation of this function has important clinical benefits. The last 30 years have seen a number of largely unsuccessful trials for beta cell preservation, some of which have been of therapies that have potential for significant harm. There is a need to explore new, more tolerable approaches to preserving beta cell function that can be implemented on a large clinical scale. Here we review the evidence for physical exercise as a therapy for the preservation of beta cell function in patients with newly diagnosed type 1 diabetes. We highlight possible mechanisms by which exercise could preserve beta cell function and then present evidence from other models of diabetes that demonstrate that exercise preserves beta cell function. We conclude by proposing that there is now a need for studies to explore whether exercise can preserve beta cell in patients newly diagnosed with type 1 diabetes.