Inspiratory Muscle Training on Glucose Control in Diabetes: A Randomized Clinical Trial.

This study evaluated the effects of inspiratory muscle training (IMT) in glucose control and respiratory muscle function in patients with diabetes. It was a randomized clinical trial conducted at the Physiopathology Laboratory of the Hospital de Clínicas de Porto Alegre. Patients with Type 2 diabetes were randomly assigned to IMT or placebo-IMT (P-IMT), performed at 30% and 2% of maximal inspiratory pressure, respectively, every day for 12 weeks. The main outcome measures were HbA1c, glycemia, and respiratory muscle function. Thirty patients were included: 73.3% women, 59.6 ± 10.7 years old, HbA1c 8.7 ± 0.9% (71.6 ± 9.8 mmol/mol), and glycemia 181.8 ± 57.8 mg/dl (10.5 ± 3.2 mmol/L). At the end of the training, HbA1c was 8.2 ±0.3% (66.1 ± 3.3 mmol/mol) and 8.7 ± 0.3% (71.6 ± 3.3 mmol/mol) for the IMT and P-IMT groups, respectively (p = .8). Fasting glycemia decreased in both groups with no difference after training although it was lower in IMT at 8 weeks: 170.0 ± 11.4 mg/dl(9.4 ± 0.6 mmol/L) and 184.4 ± 15.0 mg/dl (10.2 ± 0.8 mmol/L) for IMT and P-IMT, respectively (p < .05). Respiratory endurance time improved in the IMT group (baseline = 325.9 ± 51.1 s and 305.0 ± 37.8 s; after 12 weeks = 441.1 ± 61.7 s and 250.7 ± 39.0 s for the IMT and P-IMT groups, respectively; p < .05). Considering that glucose control did not improve, IMT should not be used as an alternative to other types of exercise in diabetes. Higher exercise intensities or longer training periods might produce better results. The clinical trials identifier is NCT03191435.

Acute inspiratory muscle exercise effect on glucose levels, glucose variability and autonomic control in patients with type 2 diabetes: A crossover randomized trial.

Inspiratory muscle exercise (IME) can be an alternative to conventional exercise. We aimed to evaluate the effect of IME on glucose, glucose variability, and autonomic cardiovascular control in type 2 diabetes. Fourteen diabetic subjects were randomly assigned to IME with 2% maximal inspiratory pressure (PImax) or 60% PImax wearing a continuous glucose monitoring system for three days. Glucose variability [glucose variance (VAR), glucose coefficient of variation (CV%), glucose standard deviation (SD), and mean amplitude of glycemic excursions (MAGE)] were evaluated. Glucose reduction was observed in 5 min (60% of PImax 33.2% and 2% of PImax 32.0%), 60 min (60% of PImax 29.6% and 2% of PImax 31.4%) and 120 min (60% of PImax 21.4% and 2% of PImax 24.0%) after IME (vs.1 h before the exercise), with no difference between loads. This reduction in glucose levels was observed in all moments of the IME protocol. Glucose variability was reduced after 12 h and 18 h of the IME (ΔCV: P < 0.001, ΔSD: P < 0.001 and ΔVAR: P < 0.001) for both loads. No difference was found in MAGE (P = 0.594) after IME. Mean arterial pressure and heart rate rose during the exercise session with 60% of PImax. Although sufficiently strong to induce cardiovascular changes, an inspiratory muscle exercise session with 60% of PImax in subjects with type 2 diabetes has failed to induce any significant improvement in glucose, glucose variability and autonomic control, compared to the 2% Plmax exercise session.

C-reactive protein and blood pressure variability in type 2 hypertensive diabetic patients.

OBJECTIVE: Increased blood pressure (BP) variability and inflammation are included among the factors recognized as potential predictors of cardiovascular events in type 2 diabetes and hypertension. This study aimed to evaluate whether C-reactive protein (CRP) is associated with increased BP variability in diabetic-hypertensive patients. PATIENTS AND METHODS: We carried out a cross-sectional study with 285 diabetic-hypertensive patients, evaluating laboratory characteristics and 24-h ambulatory BP monitoring. SD, coefficient of variation (CV%), time-rate index of 24-h systolic BP (SBP), and 24-h BP patterns were evaluated. Pearson's χ-test, Student's t-test, and the Mann-Whitney test were used to compare the groups. Groups were defined by CRP of up to 3 mg/l (low) and more than 3 mg/l (high). RESULTS: The age of the patients was 59 (54-62) years; 101 (35%) were men. There was an increase in office SBP [137 (127-148) vs. 145 (130-157) mmHg] and DBP [79 (73-86) vs. 82 (76-91) mmHg] in the high CRP group. Blood pressure variability indexes were not different among groups [SD: 11.2 (9-15) vs. 12.2 (10-15) mmHg; CV%: 8.6 (7-11) vs. 9.4 (7-12); time rate: 0.55±0.12 vs.12.2 (10-15) mmHg/min]. In addition, BMI (29.3±3.8 vs. 30.9±3.6 kg/m), total cholesterol [166 (148-190) vs. 177 (156-210) mg/dl], and HbA1c [7.5% (6.6-8.9) vs.8.3% (7.1-9.9)] were higher in the high CRP group. CONCLUSION: In patients with diabetes and hypertension, higher CRP levels are linked to cardiometabolic derangements, although they are not associated with increased BP variability.

Continuous positive airway pressure reduces blood pressure in patients with obstructive sleep apnea; a systematic review and meta-analysis with 1000 patients.

BACKGROUND: Obstructive sleep apnea (OSA) may lead to the development of hypertension and therapy with continuous positive airway pressure (CPAP) can promote reduction in blood pressure. OBJECTIVE: The objective of this study is to review systematically the effects of CPAP on blood pressure in patients with OSA. METHODS: The search was conducted in the following databases, from their beginning until February 2013: MEDLINE, Embase, Cochrane CENTRAL, Lilacs and PEDro. In addition, a manual search was performed on references of published studies. Randomized clinical trials (RCTs) that used CPAP compared with placebo CPAP or subtherapeutic CPAP for treatment of patients with OSA and that evaluated office SBP and DBP and 24-h ambulatory blood pressure were selected. RESULTS: Sixteen RCTs were included among 3409 publications, totaling 1166 patients. The use of CPAP resulted in reductions in office SBP [-3.20  mmHg; 95% confidence interval (CI) -4.67 to -1.72] and DBP (-2.87  mmHg; 95% CI -5.18 to -0.55); in night-time SBP (-4.92  mmHg; 95% CI -8.70 to -1.14); in mean 24-h blood pressure (-3.56  mmHg; 95% CI -6.79 to -0.33), mean night-time blood pressure (-2.56  mmHg; 95% CI -4.43 to -0.68) and 24-h DBP (-3.46  mmHg; 95% CI -6.75 to -0.17). However, no significant change was observed in daytime SBP (-0.74  mmHg; 95% CI -3.90 to 2.41) and daytime DBP (-1.86  mmHg; 95% CI -4.55 to 0.83). CONCLUSION: Treatment with CPAP promoted significantly but small reductions in blood pressure in individuals with OSA. Further studies should be performed to evaluate the effects of long-term CPAP and the impact on cardiovascular risk.