Tolerability and acceptability of real-time continuous glucose monitoring and its impact on diabetes management behaviours in individuals with Type 2 Diabetes - A pilot study

INTRODUCTION

Emerging evidence suggests us of real-time continuous glucose monitoring systems (RT-CGM), can assist to improve glucose control in Type 2 Diabetes (T2D) treatment, however the impact of these devices on patients' stress levels and behaviour is poorly understood. This study aimed to examine the effects of RT-CGM on tolerance and acceptability of device wear, stress and diabetes management and motivation to change.

METHODS

Twenty adults (10 men, 10 women) with T2D (aged 60.6 ± 8.4 years, BMI 34.2 ± 4.7 kg/m²), were randomised to a low-carbohydrate lifestyle plan whilst wearing a RT-CGM or an 'offline-blinded' (Blinded-CGM) monitoring system continuously for 12 weeks. Outcomes were glycaemic control (HbA1c), weight (kg) perceived stress scale (PSS), CGM device intolerance, acceptability, motivation to change and diabetes management behaviour questionnaires.

RESULTS

Both groups experienced significant reductions in body weight (RT-CGM -7.4 ± 4.5 kg vs. Blinded-CGM -5.5 ± 4.0 kg) and HbA1c (-0.67 ± 0.82% vs. -0.68 ± 0.74%). There were no differences between groups for perceived stress (P = 0.47) or device intolerance at week 6 or 12 (both P > 0.30). However, there was evidence of greater acceptance of CGM in the RT-CGM group at week 12 (P = 0.03), improved blood glucose monitoring behaviour in the RT-CGM group at week 6 and week 12 (P ≤ 0.01), and a significant time x group interaction (P = 0.03) demonstrating improved diabetes self-management behaviours in RT-CGM.

CONCLUSION

This study provides preliminary evidence of improved behaviours that accompany RT-CGM in the context of diabetes management and glucose self-monitoring. RT-CGM may provide an alternative approach to glucose management in individuals with T2D without resulting in increased disease distress.

Long-term effects of very low-carbohydrate and high-carbohydrate weight-loss diets on psychological health in obese adults with type 2 diabetes: randomized controlled trial

BACKGROUND/OBJECTIVE

Very low-carbohydrate, high-fat (LC) diets are used for type 2 diabetes (T2DM) management, but their effects on psychological health remain largely unknown. This study examined the long-term effects of an LC diet on psychological health.

METHODS

One hundred and fifteen obese adults [age: 58.5 ± 7.1 years; body mass index: 34.6 ± 4.3 kg m(-2) ; HbA1c : 7.3 ± 1.1%] with T2DM were randomized to consume either an energy-restricted (~6 to 7 MJ), planned isocaloric LC or high-carbohydrate, low-fat (HC) diet, combined with a supervised exercise programme (3 days week(-1) ) for 1 year. Body weight, psychological mood state and well-being [Profile of Mood States (POMS), Beck Depression Inventory (BDI) and Spielberger State Anxiety Inventory (SAI)] and diabetes-specific emotional distress [Problem Areas in Diabetes (PAID) Questionnaire] and quality of life [QoL Diabetes-39 (D-39)] were assessed.

RESULTS

Overall weight loss was 9.5 ± 0.5 kg (mean ± SE), with no difference between groups (P = 0.91 time × diet). Significant improvements occurred in BDI, POMS (total mood disturbance and the six subscales of anger-hostility, confusion-bewilderment, depression-dejection, fatigue-inertia, vigour-activity and tension-anxiety), PAID (total score) and the D-39 dimensions of diabetes control, anxiety and worry, sexual functioning and energy and mobility, P < 0.05 time. SAI and the D-39 dimension of social burden remained unchanged (P ≥ 0.08 time). Diet composition had no effect on the responses for the outcomes assessed (P ≥ 0.22 time × diet).

CONCLUSION

In obese adults with T2DM, both diets achieved substantial weight loss and comparable improvements in QoL, mood state and affect. These results suggest that either an LC or HC diet within a lifestyle modification programme that includes exercise training improves psychological well-being.

Steroidal contraceptive use is associated with lower bone mineral density in polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a common condition affecting reproductive-aged women with features including hyperandrogenism and menstrual irregularity frequently treated with hormonal steroidal contraceptives. Women with PCOS appear to have lower bone mineral density (BMD). While steroidal contraceptives may positively affect bone health, their effect on BMD in PCOS is not known. The aim of this study was to assess BMD in women with PCOS according to recent contraceptive use. A cross-sectional analysis of 95 pre-menopausal overweight or obese sedentary women with PCOS [age 29.4 ± 6.4 years, body mass index (BMI) 36.1 ± 5.3 kg/m(2)] who either recently took steroidal contraceptives (ceased 3 months prior) or were not taking steroidal contraceptives was conducted. Clinical outcomes included BMD, anthropometry, insulin, glucose, reproductive hormones, dietary intake and vitamin use. BMD was significantly lower for women who used contraceptives compared to those who did not (mean difference 0.06 g/cm(2) 95 % confidence interval -0.11, -0.02, p = 0.005). In regression models, lower BMD was independently associated with contraceptive use (β = -0.05, 95 % CI -0.094, -0.002, p = 0.042), higher testosterone (β = -0.03, 95 % CI -0.05, -0.0008, p = 0.043) and lower BMI (β = 0.006, 95 % CI 0.002, 0.01, p = 0.007) (r (2) = 0.22, p = 0.001 for entire model). We report for the first time that overweight and obese women with PCOS with recent steroidal contraceptive use had lower BMD in comparison to non-users independent of factors known to contribute to BMD. Whether this observation is directly related to steroidal contraceptive use or other factors requires further investigation.

Increased thiamine intake may be required to maintain thiamine status during weight loss in patients with type 2 diabetes

During weight loss, erythrocyte thiamine pyrophosphate (TPP) decreased (221±52 to 195±39 nmol/L, P<0.05) on a diet with adequate thiamine (1.1 mg/day) but was unchanged (217±55 vs 218±52 nmol/L, NS) on a high thiamine diet (2.8 mg/day). Attention to thiamine status may be required in patients with diabetes after weight loss.

The effect of diet and exercise on markers of endothelial function in overweight and obese women with polycystic ovary syndrome

BACKGROUND

Women with polycystic ovary syndrome (PCOS) present with vascular abnormalities, including elevated markers of endothelial dysfunction. There is limited evidence for the effect of lifestyle modification and weight loss on these markers. The aim of this study was to determine if 20 weeks of a high-protein energy-restricted diet with or without exercise in women with PCOS could improve endothelial function.

METHODS

This is a secondary analysis of a subset of 50 overweight/obese women with PCOS (age: 30.3 ± 6.3 years; BMI: 36.5 ± 5.7 kg/m(2)) from a previous study. Participants were randomly assigned by computer generation to one of three 20-week interventions: diet only (DO; n = 14, ≈ 6000 kJ/day), diet and aerobic exercise (DA; n = 16, ≈ 6000 kJ/day and five walking sessions/week) and diet and combined aerobic-resistance exercise (DC; n = 20, ≈ 6000 kJ/day, three walking and two strength sessions/week). At Weeks 0 and 20, weight, markers of endothelial function [vascular cell adhesion molecule-1 (sVCAM-1), inter-cellular adhesion molecule-1 (sICAM-1), plasminogen activator inhibitor-1 (PAI-1) and asymmetric dimethylarginine (ADMA)], insulin resistance and hormonal profile were assessed.

RESULTS

All three treatments resulted in significant weight loss (DO 7.9 ± 1.2%, DA 11.0 ± 1.6%, DC 8.8 ± 1.1; P < 0.001 for time; P = 0.6 time × treatment). sVCAM-1, sICAM-1 and PAI-1 levels decreased with weight loss (P≤ 0.01), with no differences between treatments (P ≥ 0.4). ADMA levels did not change significantly (P = 0.06). Testosterone, sex hormone-binding globulin and the free androgen index (FAI) and insulin resistance also improved (P < 0.001) with no differences between treatments (P ≥ 0.2). Reductions in sVCAM-1 were correlated to reductions in testosterone (r = 0.32, P = 0.03) and FAI (r = 0.33, P = 0.02) as well as weight loss (r= 0.44, P = 0.002). Weight loss was also associated with reductions in sICAM-1 (r= 0.37, P = 0.008).

CONCLUSIONS

Exercise training provided no additional benefit to following a high-protein, hypocaloric diet on markers of endothelial function in overweight/obese women with PCOS.

Self-reported facilitators of, and impediments to maintenance of healthy lifestyle behaviours following a supervised research-based lifestyle intervention programme in patients with type 2 diabetes

INTRODUCTION

Sustainability of healthy lifestyle behaviours following participation in a research-based supervised lifestyle intervention programme is often poor. This study aimed to document factors reported by overweight and obese individuals with Type 2 diabetes as enhancing or impeding sustainability of lifestyle behaviours following participation in such a programme.

METHODS

Thirty patients who completed a 16-week research-based supervised lifestyle intervention programme, incorporating a structured energy restricted diet with or without supervised resistance-exercise training underwent a semi-structured qualitative interview about their experiences in maintaining programme components after 1 year.

RESULTS

Participants maintained 8.8 ± 8.9 kg of the 13.9 ± 6.6 kg weight loss achieved with the research-based supervised lifestyle intervention programme. Only 23% of participants indicated continuation of the complete diet programme. Desire for 'variety' (33%) and increased portion size (27%) were the most commonly reported reasons for discontinuation. Participants who undertook supervised exercise training during the programme indicated access to appropriate programmes/facilities (38%), more affordable gym membership (21%) and having a personal trainer/motivator (17%) would have facilitated exercise continuation.

CONCLUSION

In overweight and obese individuals with Type 2 diabetes, success of the research-based supervised lifestyle intervention programme was perceived as being primarily due to high levels of professional support and supervision, the discontinuation of which subsequently presented difficulties. The interview data provide insight into what people experience following the completion of a research-based intensive lifestyle intervention programme and suggest that programmes assembled for research purposes with the emphasis on compliance may not necessarily promote sustainable change.

Exercise for the treatment and management of overweight women with polycystic ovary syndrome: a review of the literature

Polycystic ovary syndrome (PCOS) is characterized by the presence of polycystic ovaries, menstrual dysfunction, infertility and biochemical and clinical hyperandrogenism and is associated with an increased prevalence of cardiometabolic risk factors and psychological problems. Despite the well-established benefits of exercise training and its recommendation as a cornerstone of PCOS management, few well-controlled randomized studies have been conducted evaluating the benefits of exercise training and specific exercise regimes in women with PCOS. From the limited studies there appears to be a beneficial effect of exercise either alone or in combination with energy restriction has shown to improve fitness, cardiovascular, hormonal, reproductive and psychological outcomes. While the addition of regular exercise to energy restriction appears to only have additional benefits for improving body composition, these greater improvements are likely to have long-term implications. While lifestyle modification including regular exercise appears to be an effective strategy for the management of overweight PCOS women, methodological limitations in the studies limit the generalizability of the findings. Future research with rigorous study designs is needed to determine specific exercise guidelines that will provide the greatest benefit for these women.

A pilot comprehensive lifestyle intervention program (CLIP)--comparison with qualitative lifestyle advice and simvastatin on cardiovascular risk factors in overweight hypercholesterolaemic individuals

BACKGROUND AND AIMS

Escalating costs of pharmaceuticals for cardiovascular management highlight the need to develop effective lifestyle intervention programs to reduce reliance on these agents. The aim of this pilot study was to evaluate the efficacy of a Comprehensive Lifestyle Intervention Program (CLIP) compared with qualitative lifestyle advice (L) and Simvastatin plus qualitative lifestyle (S+L) on cardiovascular risk factors.

METHODS AND RESULTS

Sixty-five overweight adults with hypercholesterolemia were randomised to either L (qualitative advice on diet, exercise), S+L (20 mg/day Simvastatin plus L) or CLIP (6500 kJ structured menu plan: conventional and functional foods contributing <10% energy from saturated fat, ≥3 g soluble fibre, 2.4 g plant sterols, oily fish ≥2 times/week at lunch and dinner, plus exercise advice and self monitoring) for 6 weeks. LDL-cholesterol was lowered in CLIP (-0.57±0.67 mmol/L, 15%) and S+L (-1.43±0.59 mmol/L, 37%), but did not change significantly in L (-0.17±0.59, 4%) (P<0.001 time-by-treatment interaction). Weight and waist circumference were significantly lowered by CLIP (-4.2±2.2 kg; -5.1±2.3 cm) compared to L (-1.0±1.6 kg; -2.7±3.3 cm) and L+S (-0.7±1.4 kg; -2.4±2.3 cm), (P≤0.003 time-by-treatment interactions). B-carotene levels within treatment groups did not change over time and were not lowered by the CLIP diet compared to L (P>0.05, all). Blood pressure changes were not different between groups.

CONCLUSIONS

The structured CLIP program was more effective than qualitative lifestyle advice in improving weight, waist circumference and LDL-cholesterol without adverse effects on plasma carotenoids over a 6 week period. This program may therefore assist in comprehensive risk factor management, although the sustainability of these benefits needs confirmation.

Timing of protein ingestion relative to resistance exercise training does not influence body composition, energy expenditure, glycaemic control or cardiometabolic risk factors in a hypocaloric, high protein diet in patients with type 2 diabetes

AIM

To investigate timing of protein ingestion relative to resistance exercise training (RT) on body composition, cardiometabolic risk factors, glycaemic control and resting energy expenditure (REE) during weight loss on a high-protein (HP) diet in overweight and obese patients with type 2 diabetes (T2DM).

METHODS

Thirty-four men/women with T2DM (age 57 ± 7 years and body mass index 34.9 ± 4.2 kg m(-2) ) were randomly assigned to the ingestion of a HP meal (860 kJ, 21 g protein, 0.7 g fat, 29.6 g carbohydrate) either immediately prior to RT or at least 2 h following RT. All participants followed a 16-week, energy-restricted (6-7 MJ day(-1) ), HP diet (carbohydrate : protein : fat 43 : 33 : 22) and participated in supervised RT (3 day week(-1) ). Outcomes were assessed pre- and postintervention at 16 weeks.

RESULTS

There was an overall reduction in bodyweight (-11.9 ± 6.1 kg), fat mass (-10.0 ± 4.4 kg), fat-free mass (-1.9 ± 3.1 kg), waist circumference (-12.1 ± 5.3 cm), REE (-742 ± 624 kJ day(-1) ), glucose (-1.9 ± 1.7 mmol l(-1) ), insulin (-6.1 ± 6.7 mU l(-1) ) and glycosylated haemoglobin (-1.1 ± 0.1%), p ≤ 0.01 time for all variables, with no difference between groups (p ≥ 0.41 group effect). Strength improved and cardiometabolic risk factors were reduced similarly in both groups; single repetition maximum chest press 11.0 ± 8.7 kg, single repetition maximum lat pull down 9.9 ± 6.0 kg, total cholesterol -0.6 ± 0.5 mmol l(-1) , high-density lipoprotein cholesterol -0.1 ± 0.2 mmol l(-1) , low-density lipoprotein cholesterol -0.3 ± 0.5 mmol l(-1) , triglycerides -0.6 ± 0.7 mmol l(-1) , blood pressure (systolic/diastolic) -13 ± 10/-7 ± 7 mmHg (p ≤ 0.04 time effect, p ≥ 0.24 group effect).

CONCLUSION

A HP, energy-restricted diet with RT was effective in improving glycaemic control, body composition, strength and cardiometabolic risk factors in overweight/obese patients with T2DM irrespective of altering the timing of protein ingestion relative to RT.

Long-term effects of weight loss with a very low carbohydrate and low fat diet on vascular function in overweight and obese patients

OBJECTIVE

To compare the effects of an energy reduced very low carbohydrate, high saturated fat diet (LC) and an isocaloric high carbohydrate, low fat diet (LF) on endothelial function after 12 months.

DESIGN AND SUBJECTS

Forty-nine overweight or obese patients (age 50.0 +/- 1.1 years, BMI 33.7 +/- 0.6 kg m(-2)) were randomized to either an energy restricted ( approximately 6-7 MJ), planned isocaloric LC or LF for 52 weeks. Body weight, endothelium-derived factors, flow-mediated dilatation (FMD), adiponectin, augmentation index (AIx) and pulse wave velocity (PWV) were assessed. All data are mean +/- SEM.

RESULTS

Weight loss was similar in both groups (LC -14.9 +/- 2.1 kg, LF -11.5 +/- 1.5 kg; P = 0.20). There was a significant time x diet effect for FMD (P = 0.045); FMD decreased in LC (5.7 +/- 0.7% to 3.7 +/- 0.5%) but remained unchanged in LF (5.9 +/- 0.5% to 5.5 +/- 0.7%). PWV improved in both groups (LC -1.4 +/- 0.6 m s(-1), LF -1.5 +/- 0.6 m s(-1); P = 0.001 for time) with no diet effect (P = 0.80). AIx and VCAM-1 did not change in either group. Adiponectin, eSelectin, tPA and PAI-1 improved similarly in both groups (P < 0.01 for time).

CONCLUSION

Both LC and LF hypoenergetic diets achieved similar reductions in body weight and were associated with improvements in PWV and a number of endothelium-derived factors. However, the LC diet impaired FMD suggesting chronic consumption of a LC diet may have detrimental effects on endothelial function.

Comparison of aerobic exercise capacity and muscle strength in overweight women with and without polycystic ovary syndrome

OBJECTIVE

To assess maximal aerobic capacity (VO2max) and muscle strength in overweight and obese women with polycystic ovary syndrome (PCOS) and determine their relationship with metabolic and hormonal factors.

DESIGN

Cross-sectional study.

SETTING

Clinical Research Unit.

POPULATION

Overweight and obese women with PCOS (n = 10) and age-and weight-matched healthy controls (n = 16).

METHODS

VO2max was measured during an incremental treadmill test and maximal isometric (ImS) and isokinetic knee extensor strength (IkS) (120 degrees/second) were assessed by isokinetic dynamometry.

MAIN OUTCOME MEASURES

VO2max, ImS, IkS, waist circumference, blood lipids, glucose, insulin, insulin resistance (homeostatic model assessment [HOMA2]), C-reactive protein (CRP), hormonal profile.

RESULTS

PCOS women had higher levels of testosterone and free testosterone (P < or = 0.05), but there were no significant differences in any cardiovascular disease (CVD) risk markers between the groups. VO2max was similar in women with PCOS and healthy controls (PCOS 26.0 +/- 4.1 ml/kg/minute, controls 25.7 +/- 3.8 ml/kg/minute; P = 0.90), as was ImS (PCOS 1.50 +/- 0.54 Nm/kg, controls 1.50 +/- 0.47 Nm/kg; P = 0.96) and IkS (PCOS 1.04 +/- 0.32 Nm/kg, controls 1.16 +/- 0.23 Nm/kg; P = 0.32). VO2max was inversely related to waist circumference, insulin, HOMA2 and CRP. Waist circumference was inversely associated with ImS and IkS. No significant associations between exercise parameters and hormonal variables were identified.

CONCLUSIONS

Compared to age- and weight-matched healthy overweight and obese women with similar insulin resistance and CVD risk profiles, women with PCOS had similar aerobic capacity and muscle strength. This suggests PCOS, at least in the absence of an adverse metabolic profile is unlikely to limit physical function. Larger studies examining the effects of PCOS on exercise tolerance in a diverse range of PCOS phenotypes is required.

Comparison of aerobic exercise capacity and muscle strength in overweight women with and without polycystic ovary syndrome

OBJECTIVE

To assess maximal aerobic capacity (VO2max) and muscle strength in overweight and obese women with polycystic ovary syndrome (PCOS) and determine their relationship with metabolic and hormonal factors.

DESIGN

Cross-sectional study.

SETTING

Clinical Research Unit.

POPULATION

Overweight and obese women with PCOS (n = 10) and age-and weight-matched healthy controls (n = 16).

METHODS

VO2max was measured during an incremental treadmill test and maximal isometric (ImS) and isokinetic knee extensor strength (IkS) (120 degrees/second) were assessed by isokinetic dynamometry.

MAIN OUTCOME MEASURES

VO2max, ImS, IkS, waist circumference, blood lipids, glucose, insulin, insulin resistance (homeostatic model assessment [HOMA2]), C-reactive protein (CRP), hormonal profile.

RESULTS

PCOS women had higher levels of testosterone and free testosterone (P < or = 0.05), but there were no significant differences in any cardiovascular disease (CVD) risk markers between the groups. VO2max was similar in women with PCOS and healthy controls (PCOS 26.0 +/- 4.1 ml/kg/minute, controls 25.7 +/- 3.8 ml/kg/minute; P = 0.90), as was ImS (PCOS 1.50 +/- 0.54 Nm/kg, controls 1.50 +/- 0.47 Nm/kg; P = 0.96) and IkS (PCOS 1.04 +/- 0.32 Nm/kg, controls 1.16 +/- 0.23 Nm/kg; P = 0.32). VO2max was inversely related to waist circumference, insulin, HOMA2 and CRP. Waist circumference was inversely associated with ImS and IkS. No significant associations between exercise parameters and hormonal variables were identified.

CONCLUSIONS

Compared to age- and weight-matched healthy overweight and obese women with similar insulin resistance and CVD risk profiles, women with PCOS had similar aerobic capacity and muscle strength. This suggests PCOS, at least in the absence of an adverse metabolic profile is unlikely to limit physical function. Larger studies examining the effects of PCOS on exercise tolerance in a diverse range of PCOS phenotypes is required.

The effect of weight loss on anti-Müllerian hormone levels in overweight and obese women with polycystic ovary syndrome and reproductive impairment

BACKGROUND

Anti-Müllerian hormone (AMH) has been proposed as a clinical predictor of improvements in reproductive function following weight loss in overweight and obese women with polycystic ovary syndrome (PCOS). This study aimed to assess whether baseline and/or change in AMH levels with weight loss predict improvements in reproductive function in overweight and obese women with PCOS.

METHODS

Fifty-two overweight and obese women with PCOS and reproductive impairment (age 29.8 +/- 0.8 years, BMI 36.5 +/- 0.7 kg/m(2)) followed a 20-week weight loss programme. AMH, weight, menstrual cyclicity and ovulatory function were assessed at baseline and post-intervention.

RESULTS

Participants who responded with improvements in reproductive function (n = 26) had lower baseline AMH levels (23.5 +/- 3.7 versus 32.5 +/- 2.9 pmol/l; P = 0.03) and experienced greater weight loss (-11.7 +/- 1.2 versus -6.4 +/- 0.9 kg; P = 0.001) compared with those who did not respond (n = 26). Logistic regression analysis showed that weight loss and baseline AMH were independently related to improvements in reproductive function (P = 0.002 and P = 0.013, respectively). AMH levels did not change with weight loss in both responders and non-responders.

CONCLUSIONS

In overweight and obese women with PCOS and reproductive dysfunction, a 20-week weight loss intervention resulted in improvements in reproductive function but no change in AMH levels.

CLINICAL TRIALS REGISTRATION NUMBER

ACTRN12606000198527.

Effect of caloric restriction with and without exercise training on oxidative stress and endothelial function in obese subjects with type 2 diabetes

AIM

Effects of dietary weight loss on endothelial function, particularly when combined with exercise training, is largely unknown in type 2 diabetes. We sought to determine whether aerobic exercise training provided any additional improvements in endothelial function, oxidative stress or other established markers of cardiovascular risk when combined with an energy-restricted diet in patients with type 2 diabetes.

METHODS

In a parallel study design, 29 sedentary, overweight and obese patients with type 2 diabetes (age 52.4 +/- 1.4 years and BMI 34.2 +/- 0.9 kg/m(2)) were randomized to a 12-week moderate energy-restricted diet (~5000 kJ/day and approximately 30% energy deficit) with or without aerobic exercise training [diet only (D), n = 16 and diet plus exercise (DE), n = 13]. Body weight, cardiovascular risk markers, malondialdehyde (MDA, oxidative stress marker), 24-h urinary nitrate/nitrite and flow-mediated dilatation (FMD) of the brachial artery were measured pre- and postintervention.

RESULTS

Both interventions reduced body weight (D 8.9%, DE 8.5%, time effect p < 0.001). Significant reductions in body fat, waist circumference, blood pressure, glycated haemoglobin, glucose, insulin resistance, lipids and MDA and increases in urinary nitrite/nitrate were observed in both groups (time effect p < or = 0.05); however, these changes were not different between treatments. At baseline, FMD was similar in both groups (D 2.5 +/- 0.9%, DE 4.2 +/- 1.2%; p = 0.25) and did not change after the interventions (p = 0.59).

CONCLUSIONS

These results suggest that lifestyle interventions incorporating diet with or without exercise improve glycaemic control, reduce oxidative stress and improve other cardiovascular risk factors but do not improve FMD in obese subjects with type 2 diabetes.

Flow-mediated dilatation in overweight and obese women with polycystic ovary syndrome

OBJECTIVE

There remains a large degree of disagreement about the association of polycystic ovary syndrome (PCOS) with impaired endothelial dysfunction and cardiovascular disease (CVD) risk. The purpose of this study was to determine whether overweight and obese women with PCOS have impaired endothelial function compared with weight-matched controls without PCOS and whether endothelial function is associated with cardiovascular risk markers and hormonal parameters.

DESIGN

Cross-sectional analysis.

SETTING

An outpatient trial at the Commonwealth Scientific Industrial Research Organisation Clinical Research Unit.

POPULATION

Overweight and obese women with PCOS (n= 12) and weight-matched controls without PCOS (n= 10).

METHODS

Endothelial function, cardiovascular risk markers and hormonal parameters were assessed in the patients.

MAIN OUTCOME MEASURES

Endothelial function was assessed by flow-mediated dilatation (FMD) of the brachial artery using high-resolution ultrasound. Lipid profile, fasting insulin level, glucose level, insulin resistance, C-reactive protein level, folate level, Vitamin B(12) level and hormonal parameters.

RESULTS

Women with PCOS had significantly higher testosterone levels (P < 0.001) and free androgen index (P= 0.006) compared with the controls without PCOS. Both groups were normoinsulinaemic, and there were no significant differences in any of the markers of CVD between women with and without PCOS. Furthermore, FMD was similar in both groups (PCOS 6.1 +/- 1.2% versus control 5.6 +/- 1.0%, P= 0.77).

CONCLUSIONS

Compared with a group of weight-matched women with similar metabolic profiles, normoinsulinemic, overweight and obese women with PCOS did not show any greater impairment in endothelial function assessed by FMD. A normoinsulinemic phenotype of PCOS with low metabolic risk factors may reduce the risk of endothelial dysfunction in overweight and obese women with this syndrome. Further studies are required that directly compare FMD in normoinsulinemic and hyperinsulinaemic women with PCOS.

Long-term effects of advice to consume a high-protein, low-fat diet, rather than a conventional weight-loss diet, in obese adults with type 2 diabetes: one-year follow-up of a randomised trial

AIMS/HYPOTHESIS

This study compared the long-term weight loss and health outcomes at 1-year follow-up, after a 12-week intensive intervention consisting of two low-fat, weight-loss diets, which differed in protein content.

METHODS

We randomly assigned 66 obese patients (BMI: 27-40 kg/m2) with type 2 diabetes to either a low-protein (15% protein, 55% carbohydrate) or high-protein diet (30% protein, 40% carbohydrate) for 8 weeks of energy restriction (approximately 6.7 MJ/day) and 4 weeks of energy balance. Subjects were asked to maintain the same dietary pattern for a further 12 months of follow-up.

RESULTS

The study was completed by 38 of the subjects, with equal dropouts in each group. At Week 64, weight reductions against baseline were -2.2+/-1.1 kg (low protein) and -3.7+/-1.0 kg (high protein), p<0.01, with no diet effect. Fat mass was not different from baseline in either group. At Week 12, both diets reduced systolic and diastolic blood pressure by 6 and 3 mm Hg respectively, but blood pressure increased more with weight regain during follow-up in the low-protein group (p< or =0.04). At Week 64, both diets significantly increased HDL cholesterol and lowered C-reactive protein concentrations. There was no difference in the urinary urea : creatinine ratio at baseline between the two groups, but this ratio increased at Week 12 (in the high-protein group only, p<0.001, diet effect), remaining stable during follow-up in both diets.

CONCLUSIONS/INTERPRETATION

A high-protein weight-reduction diet may in the long term have a more favourable cardiovascular risk profile than a low-protein diet with similar weight reduction in people with type 2 diabetes.

Long-term effects of a high-protein, low-carbohydrate diet on weight control and cardiovascular risk markers in obese hyperinsulinemic subjects

OBJECTIVE

To compare the long-term compliance and effects of two low-fat diets differing in carbohydrate to protein ratio on body composition and biomarkers of cardiovascular disease risk in obese subjects with hyperinsulinemia.

DESIGN

Outpatient, parallel, clinical intervention study of two groups of subjects randomly assigned to either a standard protein (SP; 15% protein, 55% carbohydrate) or high-protein (HP; 30% protein, 40% carbohydrate) diet, during 12 weeks of energy restriction (approximately 6.5 MJ/day) and 4 weeks of energy balance (approximately 8.3 MJ/day). Subsequently, subjects were asked to maintain the same dietary pattern for the succeeding 52 weeks with minimal professional support.

SUBJECTS

A total of 58 obese, nondietetic subjects with hyperinsulinemia (13 males/45 females, mean age 50.2 y, mean body mass index (BMI) 34.0 kg/m2, mean fasting insulin 17.8 mU/l) participated in the study.

MEASUREMENTS

: Body composition, blood pressure, blood lipids, fasting glucose, insulin, CRP and sICAM-1 were measured at baseline and at weeks 16 and 68. Urinary urea/creatinine ratio was measured at baseline, week 16 and at 3 monthly intervals thereafter.

RESULTS

In total, 43 subjects completed the study with similar dropouts in each group (P=0.76). At week 68, there was net weight loss (SP -2.9+/-3.6%, HP -4.1+/-5.8%; P<0.44) due entirely to fat loss (P<0.001) with no diet effect [corrected]. Both diets significantly increased HDL cholesterol concentrations (P<0.001) and decreased fasting insulin, insulin resistance, sICAM-1 and CRP levels (P<0.05). Protein intake was significantly greater in HP during the initial 16 weeks (P<0.001), but decreased in HP and increased in SP during 52-week follow-up, with no difference between groups at week 68, indicating poor long-term dietary adherence behaviour to both dietary patterns.

CONCLUSION

Without active ongoing dietary advice, adherence to dietary intervention is poor. Nonetheless, both dietary patterns achieved net weight loss and improvements in cardiovascular risk factors.

Bovine colostrum supplementation during endurance running training improves recovery, but not performance

This study examined the effect of supplementation with concentrated bovine colostrum protein powder (intact) on plasma insulin-like growth factor I (IGF-I) concentrations, endurance running performance and recovery. Thirty physically active males completed 8 weeks of running training whilst consuming 60 g x day(-1) of intact powder (n=17) or a concentrated whey protein powder placebo (n=13) in a randomised, double-blind, parallel design. Plasma IGF-I concentrations were measured prior to subjects performing two (approximately 30 min) incremental treadmill running tests to exhaustion (RUN1 and RUN2) separated by 20 min of passive recovery at Weeks 0. 4 and 8. Plasma IGF-I concentrations showed little change in either group (p=0.83). Effective peak running speed (PRSE; i.e. equivalent of peak power) during RUN1 was not different between groups at Week 0 (p>0.99), and had increased by a similar amount in both groups by Week 4 (mean+/-SD, intact 2.2+/-4.0%, placebo 3.2+/-3.3%; 95% confidence interval [95% CI 15.7 to -13.7%; p=0.89) and Week 8 (intact 3.6+/-5.6%, placebo 3.4+/-4.4 %; 95% CI -100.0 to 100.0%; p>0.99). PRSE was less in both groups during RUN2 (p<0.05), but was not significantly different between groups at Week 0 (p>0.99). PRSE during RUN2 tended to have increased more in the placebo group by Week 4 (intact 1.8+/-4.8%, placebo 4.2+/-3.9%; 95% CI 0.2 to -5 0%; p=0.07), but the intact group had increased PRSE significantly more by Week 8 (intact 4.6+/-6.1%, placebo 2.0+/-4.5%; 95% Cl 0.0 to 5.2%; p=0.05). resulting in a significantly faster PRSE (p=0.003). We conclude that supplementation with intact powder did not increase plasma IGF-I concentrations or improve performance during an initial bout of incremental running to exhaustion in our sample. However, performance during a second bout of exercise may be improved by as much as 5.2% in the average subject after 8 weeks of supplementation, possibly due to an enhancement of recovery.