A comparison of the health benefits of reduced-exertion high-intensity interval training (REHIT) and moderate-intensity walking in type 2 diabetes patients

Reduced-exertion high-intensity interval training (REHIT) is a genuinely time-efficient intervention that can improve aerobic capacity and insulin sensitivity in sedentary individuals. The present study compared the effects of REHIT and moderate-intensity walking on health markers in patients with type 2 diabetes (T2D) in a counter-balanced crossover study. Sixteen men with T2D (mean ± SD age: 55 ± 5 years, body mass index: 30.6 ± 2.8 kg·m^-2, maximal aerobic capacity: 27 ± 4 mL·kg^-1·min^-1) completed 8 weeks of REHIT (three 10-min low-intensity cycling sessions/week with two "all-out" 10-20-s sprints) and 8 weeks of moderate-intensity walking (five 30-min sessions/week at an intensity corresponding to 40%-55% of heart-rate reserve), with a 2-month wash-out period between interventions. Before and after each intervention, participants underwent an incremental fitness test, an oral glucose tolerance test (OGTT), a whole-body dual-energy X-ray absorptiometry scan, and continuous glucose monitoring. REHIT was associated with a significantly larger increase in maximal aerobic capacity compared with walking (7% vs. 1%; time × intervention interaction effect: p < 0.05). Both REHIT and walking decreased resting mean arterial pressure (-4%; main effect of time: p < 0.05) and plasma fructosamine (-5%; main effect of time: p < 0.05). Neither intervention significantly improved OGTT-derived measures of insulin sensitivity, glycaemic control measured using continuous glucose monitors, blood lipid profile, or body composition. We conclude that REHIT is superior to a 5-fold larger volume of moderate-intensity walking in improving aerobic fitness, but similar to walking REHIT is not an effective intervention for improving insulin sensitivity or glycaemic control in T2D patients in the short term.

Magnesium-zinc-calcium-vitamin D co-supplementation improves glycemic control and markers of cardiometabolic risk in gestational diabetes: a randomized, double-blind, placebo-controlled trial

To the best our knowledge, data on the effects of magnesium-zinc-calcium-vitamin D co-supplementation on glycemic control and markers of cardiometabolic risk in gestational diabetes mellitus (GDM) are scarce. The purpose of this study was to establish the effects of magnesium-zinc-calcium-vitamin D co-supplementation on glycemic control and markers of cardiometabolic risk of GDM patients. Sixty patients with GDM, aged 18-40 years, were randomized into 2 groups to intake either magnesium-zinc-calcium-vitamin D co-supplements or placebo (n = 30 each group) for 6 weeks in a randomized, double-blind, placebo-controlled trial. Fasting blood samples were taken at baseline and week 6 to quantify related markers. After the 6-week intervention, compared with the placebo, magnesium-zinc-calcium-vitamin D co-supplementation resulted in significant reductions in fasting plasma glucose (-0.37 ± 0.09 vs. +0.01 ± 0.09 mmol/L, P = 0.003), serum insulin levels (-21.0 ± 4.8 vs. +7.2 ± 4.8 pmol/L, P < 0.001), homeostatic model of assessment for insulin resistance (-1.0 ± 1.1 vs. +0.3 ± 1.3, P < 0.001), and a significant increase in quantitative insulin sensitivity check index (+0.02 ± 0.03 vs. -0.002 ± 0.03, P = 0.003). In addition, magnesium-zinc-calcium-vitamin D co-supplementation significantly decreased serum triglycerides (-0.25 ± 0.10 vs. +0.34 ± 0.10 mmol/L, P = 0.001) and very-low-density-cholesterol concentrations (-0.11 ± 0.04 vs. +0.15 ± 0.04 mmol/L, P = 0.001) compared with the placebo. Overall, the results of this study demonstrated that magnesium-zinc-calcium-vitamin D co-supplementation for 6 weeks among patients with GDM had beneficial effects on glycemic control and few markers of cardiometabolic risk.

Does the type of activity "break" from prolonged sitting differentially impact on postprandial blood glucose reductions? An exploratory analysis

Frequent breaks in prolonged sitting are associated beneficially with glycaemic control. However, the contribution of energy expenditure to this relationship has not been well characterised. In this exploratory analysis, data from 3 laboratory trials that standardised test meals, cohort characteristics (overweight/obese, sedentary), and break frequency and duration were pooled. Higher energy expenditures of different types of breaks (standing, light- or moderate-intensity walking) were associated with lower postprandial glucose and insulin responses in a dose-dependent manner.

Disease characteristics and treatment of patients with diabetes mellitus attending government health services in Indonesia, Peru, Romania and South Africa

OBJECTIVE

To describe the characteristics and management of Diabetes mellitus (DM) patients from low- and middle-income countries (LMIC).

METHODS

We systematically characterised consecutive DM patients attending public health services in urban settings in Indonesia, Peru, Romania and South Africa, collecting data on DM treatment history, complications, drug treatment, obesity, HbA1c and cardiovascular risk profile; and assessing treatment gaps against relevant national guidelines.

RESULTS

Patients (median 59 years, 62.9% female) mostly had type 2 diabetes (96%), half for >5 years (48.6%). Obesity (45.5%) and central obesity (females 84.8%; males 62.7%) were common. The median HbA1c was 8.7% (72 mmol/mol), ranging from 7.7% (61 mmol/mol; Peru) to 10.4% (90 mmol/mol; South Africa). Antidiabetes treatment included metformin (62.6%), insulin (37.8%), and other oral glucose-lowering drugs (34.8%). Disease complications included eyesight problems (50.4%), EGFR <60 ml/min (18.9%), heart disease (16.5%) and proteinuria (14.7%). Many had an elevated cardiovascular risk with elevated blood pressure (36%), LDL (71.0%) and smoking (13%), but few were taking antihypertensive drugs (47.1%), statins (28.5%) and aspirin (30.0%) when indicated. Few patients on insulin (8.0%), statins (8.4%) and antihypertensives (39.5%) reached treatment targets according to national guidelines. There were large differences between countries in terms of disease profile and medication use.

CONCLUSION

DM patients in government clinics in four LMIC with considerable growth of DM have insufficient glycaemic control, frequent macrovascular and other complications, and insufficient preventive measures for cardiovascular disease. These findings underline the need to identify treatment barriers and secure optimal DM care in such settings.

Pre- and within-meal effects of fluid dairy products on appetite, food intake, glycemia, and regulatory hormones in children

The effect of beverages commonly consumed by children in-between or with meals on short-term food intake (FI) and glycemic control has received little attention. Therefore, 2 experiments were conducted in 9- to 14-year-old children following a randomized repeated-measures design. Experiment 1 (n = 32) compared the effects of water (control) and isocaloric (130 kcal) amounts of 2% milk, chocolate milk, yogurt drink, and fruit punch on subjective appetite and FI. Experiment 2 (n = 20) compared the effects of isocaloric (130 kcal) amounts of 2% milk and fruit punch on subjective appetite, FI, and glycemic and appetite hormone responses. One serving of the beverages was given as a pre-meal drink at baseline (0 min) and a second serving 60 min later with an ad libitum pizza meal. Meal FI in experiment 1 was lower by 14% and 10%, respectively, after chocolate milk and yogurt drink (p < 0.001), but not milk, compared with water. Cumulative energy intake (beverages plus meal) was higher after caloric beverages than water. In experiment 2, no differences occurred in pre-meal but post-meal glucose was 83% higher in overweight/obese than normal-weight children (p = 0.02). Milk led to higher pre-meal glucagon-like peptide-1 and post-meal peptide tyrosine tyrosine (PYY) than fruit punch (p < 0.01) but insulin did not differ between treatments. In conclusion, dairy products consumed before and with a meal have more favourable effects on FI, appetite, and satiety hormones than a sugar-sweetened beverage, but all caloric beverages result in more cumulative calories than if water is the beverage.

Prior ingestion of a ketone monoester supplement reduces postprandial glycemic responses in young healthy-weight individuals

The main objective of this study was to determine whether acute ingestion of a ketone monoester (KME) supplement impacted mixed-meal tolerance test (MMTT) glucose area under the curve (AUC). Nineteen healthy young volunteers (10 males/9 females; age, 24.7 ± 4.9 years; body mass index, 22.7 ± 2.4 kg/m²) participated in a double-blind, placebo-controlled crossover study. Following overnight fasting (≥10 h), participants consumed 0.45 mL/kg of a KME supplement or taste-matched placebo followed by an MMTT 15 min later. Blood samples were collected every 15-30 min over 2.5 h. KME supplementation acutely raised β-hydroxybutyrate AUC (590%, P < 0.0001, d = 2.4) and resulted in decreases in blood glucose AUC (-9.4%, P = 0.03, d = 0.56) and nonesterified fatty acid (NEFA) AUC (-27.3%, P = 0.023, d = 0.68) compared with placebo. No differences were found for plasma insulin AUC (P = 0.70) or gastric emptying estimated by co-ingested acetaminophen AUC (P = 0.96) between ketone and placebo. Overall, results indicate that KME supplementation attenuates postprandial glycemic and NEFA responses when taken 15 min prior to a mixed meal in young healthy individuals. Future studies are warranted to investigate whether KME supplementation may benefit individuals with impaired glycemic control. Novelty: Acute ketone monoester supplementation 15 min prior to a mixed meal decreased postprandial glucose and NEFA levels without significantly impacting postprandial insulin or estimates of gastric emptying. Glucose- and NEFA-lowering effects of ketone monoester supplementation are apparently not mediated by changes in insulin release or gastric emptying.

Influence of a Pay-for-Performance Program on Glycemic Control in Patients Living with Diabetes by Family Physicians in a Canadian Province

OBJECTIVES

We evaluated the influence of the introduction of a pay-for-performance program implemented in 2010 for family physicians on the glycemic control of patients with diabetes.

METHODS

Administrative data for all 583 eligible family physicians and 83,580 adult patients with diabetes in New Brunswick over 10 years were used. We compared the probability of receiving at least 2 tests for glycated hemoglobin (A1C) levels and achieving glycemic control before (2005-2009) and after (2010-2014) the implementation of the program and between patients divided based on whether a physician claimed the incentive or did not.

RESULTS

Patients living with diabetes showed greater odds of receiving at least 2 A1C tests per year if the detection of their diabetes occurred after (vs. before) the implementation of the program (OR, 99% CI=1.23, 1.18 to 1.28), if a physician claimed the incentive (vs. not claiming it) for their care (1.92, 1.87 to 1.96) in the given year, and if they were followed by a physician who ever (vs. never) claimed the incentive (1.24, 1.15 to 1.34). In a cohort-based analysis, patients for whom an incentive was claimed (vs. not claimed) had greater odds of receiving at least 2 A1C tests per year before implementation of the incentive, and these odds increased by 56% (1.49 to 1.62) following its implementation. However, there was no difference in A1C values among the various comparison groups.

CONCLUSIONS

Introduction of the incentive was associated with greater odds of having a minimum of 2 A1C tests per year, which may suggest that it led physicians to provide better follow-up care for patients with diabetes. However, the incentive program has not been associated with differences in glycemic control.

Blunted circulating irisin in adults with type 1 diabetes during aerobic exercise in a hot environment: a pilot study

Irisin is a novel myokine associated with increased metabolism, which may be upregulated in type 1 diabetes (T1D) during exercise-heat stress. We therefore assessed serum irisin production in young adults with and without T1D during incremental exercise in dry-heat (35 °C). The change in irisin during exercise was lower in individuals with compared with without T1D (-1.79 (SEM 25.68) vs. 59.74 (SEM 79.63) pg/mL; p = 0.024), indicating that irisin expression during exercise-heat stress is blunted in T1D. Novelty We show that, when assessed in young adults with and without T1D during exercise-heat stress, serum irisin production is blunted in T1D.

Dietary restriction in moderately obese rats improves body size and glucose handling without the renal and hepatic alterations observed with a high-protein diet

Obesity is increasing worldwide, and high-protein (HP) diets are widely used for weight loss. However, the overall safety of HP diets is not well established in obese individuals, who make up a significant proportion of the population. To evaluate the health effects of an HP diet in obesity, obesity-prone (OP) Sprague-Dawley rats were given high-fat diets for 12 weeks to induce obesity. Following this, for 8 more weeks, these rats were given either a normal-protein (NP) (15% of energy) or an HP (35% of energy) diet ad libitum, or the NP diet at a restricted level to achieve body weights similar to those of the HP group (pair-weighted (PW) group). Obesity-resistant (OR) control rats were also given the NP diet throughout the feeding period. The HP-OP group had higher food intake but lower body weight, improved glucose handling, and lowered serum haptoglobin compared with the NP-OP group. These benefits were also observed in PW-OP rats. In addition, PW-OP rats had less fat accumulation when compared with NP-OP rats, and an improved Lee index, lower liver size, and lower serum alanine aminotransferase when compared with HP-OP rats. On the other hand, kidney size, proteinuria, and serum homocysteine were increased in HP-OP rats compared with NP-OP rats, whereas PW-OP rats did not experience these effects. These results indicate that in obese rats, more benefits are obtained via dietary restriction with an NP diet and without some of the potentially detrimental effects of an HP diet.

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.

Association of Fructosamine Levels With Glycemic Management in Children With Type 1 Diabetes as Determined by Continuous Glucose Monitoring: Results From the CGM TIME Trial

OBJECTIVE

Our aim in this study was to determine the correlation between serum fructosamine and average blood glucose, as measured by continuous glucose monitoring (CGM) in children with type 1 diabetes.

METHODS

Ninety-seven blood samples were collected from 70 participants in the Timing of Initiation of continuous glucose Monitoring in Established pediatric diabetes (CGM TIME) Trial. Each eligible participant had 3 weeks of CGM data with at least 60% CGM adherence before blood collection. Ordinary least-squares linear regression incorporating restricted cubic splines was used to determine the association between fructosamine levels and mean blood glucose.

RESULTS

An association was found between fructosamine and mean blood glucose, with an F statistic of 9.543 (p<0.001). Data were used to create a formula and conversion chart for calculating mean blood glucose from fructosamine levels for clinical use.

CONCLUSIONS

There is a complex relationship between average blood glucose, as determined by CGM and fructosamine. Fructosamine levels may be clinically useful for assessing short-term glycemic management when CGM is not available.

Glycemic Management in Diabetic Foot Ulcers: A Comparative Analysis of Wound and Wound-free Periods in Adults With Type 1 and Type 2 Diabetes

OBJECTIVE

Our aim in this study was to determine whether there are differences in glycemia during wound and wound-free states among individuals with diabetes at a multidisciplinary diabetic foot and wound clinic from 2012 to 2019.

METHODS

We conducted a retrospective analysis of prospectively collected data over 7.4 years from the Johns Hopkins Multidisciplinary Diabetic Foot and Wound Clinic. Participants with diabetic foot ulcers were observed during at least one wound period and one wound-free period and had at least one glycated hemoglobin (A1C) measurement in both a wound period and a wound-free period. The A1C measurements were aggregated and summarized across wound and wound-free periods, and compared using the Wilcoxon matched-pairs signed rank test.

RESULTS

Two hundred six eligible participants with a total of 623 wounds were included in this analysis. Participants were followed for a median period of 2.4 years (876 days). There were no significant differences in mean, minimum, and maximum A1C between the aggregate wound and wound-free periods, with median values of 7.6% (interquartile range [IQR] 6.6% to 9.1%) and 7.5% (IQR 6.6% to 9.1%) for mean A1C (p=0.43), 6.9% (IQR 6.0% to 8.0%) and 6.8% (6.0% to 8.1%) for minimum A1C (p=0.78), and 8.6% (IQR 7.1% to 10.9%) and 8.5% (IQR 7.0% to 10.7%) for maximum A1C (p=0.06) in the wound and wound-free periods, respectively.

CONCLUSIONS

This retrospective study shows similar levels of A1C during wound and wound-free periods; however, given the limitations of missing A1C and small sample size, further studies leveraging continuous glucose monitoring are needed to determine whether glycemia worsens in the setting of a DFU.