Validity of Ratings of Perceived Exertion in Patients with Type 2 Diabetes

PURPOSE

To examine whether a subjective measure of moderate-intensity exercise (12-13 on Borg's ratings of perceived exertion scale; RPE) corresponds to the target heart rate for moderate-intensity exercise (40-59% heart rate reserve; %HRR) and to determine the characteristics of those for whom RPE does not appropriately estimate exercise intensity.

METHODS

3582 individuals with type 2 diabetes (age: 58.3±6.8 years; BMI: 35.9±5.9 kg/m²) underwent a maximal exercise test and minute-by-minute HR and RPE were recorded. Linear regression was used to determine the %HRR corresponding to an RPE of 12 and 13 for each individual.

RESULTS

At an RPE of 12 or 13, 57% of participants fell within the target 40-59%HRR range, while 37% and 6% fell above and below this range, respectively. Participants with a %HRR ≥60% (above range) were more likely to be female (OR: 1.19; 95% CI: 1.01,1.40), African American (OR: 1.65; 95% CI: 1.35, 2.02) or Hispanic (OR: 1.57; 95% CI: 1.27, 1.95), have a higher BMI (OR: 1.03; 95% CI 1.01, 1.04) and HR_max (OR: 1.02; 95% CI: 1.01, 1.02), and lower fitness (OR: 0.90; 95% CI: 0.85, 0.94) and RPE_max (OR: 0.68; 95% CI: 0.63, 0.73), compared to those within the target 40-59%HRR range (p-values'<0.05).

CONCLUSIONS

RPE appropriately gauges exercise intensity in approximately half of overweight individuals with type 2 diabetes; however, more than one-third of participants were at an increased risk of exercising at a higher than prescribed intensity when using RPE. Future studies should continue to examine the characteristics of individuals for whom RPE appropriately estimates exercise intensity and for those whom it does not.

Sex differences in cardiovascular disease risk and exercise in type 2 diabetes

Diabetes currently affects approximately 14% of the US population, and cardiovascular disease (CVD) is a leading cause of morbidity and mortality in those with diabetes. Although in the general population women are at lower risk than men for CVD, women have a disproportionately greater increase in risk for CVD than do men in the context of diabetes. Physical activity is considered a cornerstone in the prevention and treatment of CVD and its risk factors, but greater barriers to physical activity may exist for women with diabetes compared to their male counterparts. In this article, we review sex differences in CVD incidence and risk among diabetics, sex differences in physical activity behaviors, cardiovascular abnormalities and impaired exercise capacity in women living with diabetes, and the effects of exercise on prevention and treatment of CVD in diabetic women. Finally, we discuss future research needed to clarify potential sex differences in the cardiovascular effects of diabetes and to establish ways to reduce the barriers to exercise in women with diabetes.

Impact of weight loss on ankle-brachial index and interartery blood pressures

OBJECTIVE

To assess whether weight loss improves markers of peripheral artery disease and vascular stenosis.

METHODS

The Action for Health in Diabetes randomized clinical trial compared intensive lifestyle intervention (ILI) for weight loss to a control condition of diabetes support and education (DSE) in overweight or obese adults with type 2 diabetes. Annual ankle and brachial blood pressures over four years were used to compute ankle-brachial indices (ABIs) and to assess interartery blood pressure differences in 5018 participants.

RESULTS

ILI, compared to DSE, produced 7.8% (Year 1) to 3.6% (Year 4) greater weight losses. These did not affect prevalence of low (<0.90) ABI (3.60% in DSE versus 3.14% in ILI; P = 0.20) or elevated (>1.40) ABI (7.52% in DSE versus 7.59% in ILI: P = 0.90), but produced smaller mean (SE) maximum interartery systolic blood pressure differences among ankle sites [19.7 (0.2) mmHg for ILI versus 20.6 (0.2) mmHg for DSE (P < 0.001)] and between arms [5.8 (0.1) mmHg for ILI versus 6.1 (0.1) mmHg for DSE (P = 0.01)].

CONCLUSIONS

Four years of intensive behavioral weight loss intervention did not significantly alter prevalence of abnormal ABI, however, it did reduce differences in systolic blood pressures among arterial sites.

Correlation of patient-reported symptom outcomes and treadmill test outcomes after treatment for aortoiliac claudication

PURPOSE

To examine the relationship between objective treadmill test outcomes and subjective symptom outcomes among patients with claudication treated with stent revascularization (ST) compared with supervised exercise (SE).

MATERIALS AND METHODS

Five scales of the Peripheral Artery Questionnaire and Walking Impairment Questionnaire were correlated with peak walking time and treadmill claudication onset time.

RESULTS

The correlation between change in disease-specific quality of life (QOL) and change in peak walking time differed according to treatment group, with statistically significant correlations for all five scales for the ST group and weaker trends for the SE group, only one of which was statistically significant. In contrast, improvements in disease-specific QOL correlated well with increases in claudication onset time, with no significant interaction with treatment group for any of the five scales.

CONCLUSIONS

Disease-specific QOL results at 6 months in the Claudication: Exercise Vs. Endoluminal Revascularization (CLEVER) study show that improved maximal treadmill walking in patients with claudication treated with SE correlated poorly with self-reported symptom relief. Conversely, patients treated with ST showed good correlation between improved maximal treadmill walking and self-reported symptom improvement. The correlation between claudication onset time and self-reported symptom relief was good across treatment groups. This finding indicates that traditional objective treadmill test outcomes may not correlate well with symptom relief in patients with claudication. Future studies should investigate these data and improve understanding of patient relevance of traditional objective treadmill-based treatment outcomes.

Cardiovascular effects of intensive lifestyle intervention in type 2 diabetes

BACKGROUND

Weight loss is recommended for overweight or obese patients with type 2 diabetes on the basis of short-term studies, but long-term effects on cardiovascular disease remain unknown. We examined whether an intensive lifestyle intervention for weight loss would decrease cardiovascular morbidity and mortality among such patients.

METHODS

In 16 study centers in the United States, we randomly assigned 5145 overweight or obese patients with type 2 diabetes to participate in an intensive lifestyle intervention that promoted weight loss through decreased caloric intake and increased physical activity (intervention group) or to receive diabetes support and education (control group). The primary outcome was a composite of death from cardiovascular causes, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for angina during a maximum follow-up of 13.5 years.

RESULTS

The trial was stopped early on the basis of a futility analysis when the median follow-up was 9.6 years. Weight loss was greater in the intervention group than in the control group throughout the study (8.6% vs. 0.7% at 1 year; 6.0% vs. 3.5% at study end). The intensive lifestyle intervention also produced greater reductions in glycated hemoglobin and greater initial improvements in fitness and all cardiovascular risk factors, except for low-density-lipoprotein cholesterol levels. The primary outcome occurred in 403 patients in the intervention group and in 418 in the control group (1.83 and 1.92 events per 100 person-years, respectively; hazard ratio in the intervention group, 0.95; 95% confidence interval, 0.83 to 1.09; P=0.51).

CONCLUSIONS

An intensive lifestyle intervention focusing on weight loss did not reduce the rate of cardiovascular events in overweight or obese adults with type 2 diabetes. (Funded by the National Institutes of Health and others; Look AHEAD ClinicalTrials.gov number, NCT00017953.).

Cardiovascular effects of intensive lifestyle intervention in type 2 diabetes

BACKGROUND

Weight loss is recommended for overweight or obese patients with type 2 diabetes on the basis of short-term studies, but long-term effects on cardiovascular disease remain unknown. We examined whether an intensive lifestyle intervention for weight loss would decrease cardiovascular morbidity and mortality among such patients.

METHODS

In 16 study centers in the United States, we randomly assigned 5145 overweight or obese patients with type 2 diabetes to participate in an intensive lifestyle intervention that promoted weight loss through decreased caloric intake and increased physical activity (intervention group) or to receive diabetes support and education (control group). The primary outcome was a composite of death from cardiovascular causes, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for angina during a maximum follow-up of 13.5 years.

RESULTS

The trial was stopped early on the basis of a futility analysis when the median follow-up was 9.6 years. Weight loss was greater in the intervention group than in the control group throughout the study (8.6% vs. 0.7% at 1 year; 6.0% vs. 3.5% at study end). The intensive lifestyle intervention also produced greater reductions in glycated hemoglobin and greater initial improvements in fitness and all cardiovascular risk factors, except for low-density-lipoprotein cholesterol levels. The primary outcome occurred in 403 patients in the intervention group and in 418 in the control group (1.83 and 1.92 events per 100 person-years, respectively; hazard ratio in the intervention group, 0.95; 95% confidence interval, 0.83 to 1.09; P=0.51).

CONCLUSIONS

An intensive lifestyle intervention focusing on weight loss did not reduce the rate of cardiovascular events in overweight or obese adults with type 2 diabetes. (Funded by the National Institutes of Health and others; Look AHEAD ClinicalTrials.gov number, NCT00017953.).

The PADQOL: development and validation of a PAD-specific quality of life questionnaire

Understanding the impact of peripheral artery disease (PAD) requires broad evaluation of how functional limitations of PAD affect patients' perceptions of health-related quality of life (HRQL). The objective of this study was to describe the development, testing, and psychometric properties of the PAD Quality of Life Questionnaire (PADQOL). The PADQOL was developed in three steps: (1) interviews of symptomatic PAD patients provided content of the initial questionnaire; (2) co-administration with the SF-36 (a 36-item short-form health survey), Walking Impairment Questionnaire, and Profile of Mood States examined construct validity; and (3) a three-phased factor analysis identified factors and shortened the questionnaire. Data analyses from 297 symptomatic PAD patients resulted in a 38-item questionnaire of five factors: Social relationships and interactions, Self-concept and feelings, Symptoms and limitations in physical functioning, Fear and uncertainty, and Positive adaptation (α = 0.92-0.73) and items related to sexual function, intimate relationships and employment. Between-instrument correlations established construct validity. In conclusion, PADQOL is a validated measure to assess the disease-specific physical, psychosocial and emotional effects of PAD for research and practice.

Four-year change in cardiorespiratory fitness and influence on glycemic control in adults with type 2 diabetes in a randomized trial: the Look AHEAD Trial

OBJECTIVE

To examine an intensive lifestyle intervention (ILI) compared with diabetes support and education (DSE) on 4-year change in fitness and physical activity (PA), and to examine the effect of change in fitness and PA, adjusting for potential confounders, on glycemic control in the Look AHEAD Trial.

RESEARCH DESIGN AND METHODS

Subjects were overweight/obese adults with type 2 diabetes mellitus (T2DM) with available fitness data at 4 years (n = 3,942).This clinical trial randomized subjects to DSE or ILI. DSE subjects received standard care plus information related to diet, PA, and social support three times per year. ILI subjects received weekly intervention contact for 6 months, which was reduced over the 4-year period, and were prescribed diet and PA. Measures included weight, fitness, PA, and HbA1c.

RESULTS

The difference in percent fitness change between ILI and DSE at 4 years was significant after adjustment for baseline fitness and change in weight (3.70 vs. 0.94%; P < 0.01). At 4 years, PA increased by 348 (1,562) kcal/week in ILI vs. 105 (1,309) kcal/week in DSE (P < 0.01). Fitness change at 4 years was inversely related to change in HbA1c after adjustment for clinical site, treatment, baseline HbA1c, prescribed diabetes medication, baseline fitness, and weight change (P < 0.01). Change in PA was not related to change in HbA1c.

CONCLUSIONS

A 4-year ILI increased fitness and PA in overweight/obese individuals with T2DM. Change in fitness was associated with improvements in glycemic control, which provides support for interventions to improve fitness in adults with T2DM.

Exercise therapy for claudication: latest advances

OPINION STATEMENT

Peripheral artery disease (PAD) creates a significant national and international healthcare burden. A first line treatment for PAD is supervised walking exercise in hospitals and clinics. Specifically, supervised walking exercise seeks to improve the classic symptom associated with PAD, intermittent claudication (IC), which is characterized by cramping, aching, and pain of the muscles in the lower extremities during walking. While effective, supervised walking exercise is often not prescribed or utilized due to a number of treatment barriers such as lack of transportation to clinical centers and lack of insurance reimbursement. Walking exercise in community settings is an option that has gained attention due to the limitations of supervised walking exercise, as community walking is generally more convenient in terms of a patient's schedule and may circumvent potential barriers such as treatment cost and transportation difficulties. However, more research is needed to improve the effectiveness of community-based walking programs since far less is known about the optimal structure of such programs. Other exercise therapy options are becoming available for PAD patients in addition to walking exercise. These modalities include but are not limited to leg and arm ergometry, polestriding and resistance training. These exercise therapy options have not to date been as well validated as supervised walking exercise. However, they may potentially be used in the event supervised walking exercise is not feasible or patient preference warrants an alternative exercise strategy.

Type 2 diabetes mellitus and exercise impairment

Limitations in physical fitness, a consistent finding in individuals with both type I and type 2 diabetes mellitus, correlate strongly with cardiovascular and all-cause mortality. These limitations may significantly contribute to the persistent excess cardiovascular mortality affecting this group. Exercise impairments in VO2 peak and VO2 kinetics manifest early on in diabetes, even with good glycemic control and in the absence of clinically apparent complications. Subclinical cardiac dysfunction is often present but does not fully explain the observed defect in exercise capacity in persons with diabetes. In part, the cardiac limitations are secondary to decreased perfusion with exercise challenge. This is a reversible defect. Similarly, in the skeletal muscle, impairments in nutritive blood flow correlate with slowed (or inefficient) exercise kinetics and decreased exercise capacity. Several correlations highlight the likelihood of endothelial-specific impairments as mediators of exercise dysfunction in diabetes, including insulin resistance, endothelial dysfunction, decreased myocardial perfusion, slowed tissue hemoglobin oxygen saturation, and impairment in mitochondrial function. Both exercise training and therapies targeted at improving insulin sensitivity and endothelial function improve physical fitness in subjects with type 2 diabetes. Optimization of exercise functions in people with diabetes has implications for diabetes prevention and reductions in mortality risk. Understanding the molecular details of endothelial dysfunction in diabetes may provide specific therapeutic targets for the remediation of this defect. Rat models to test this hypothesis are under study.

Best practices and pearls in interdisciplinary mentoring from Building Interdisciplinary Research Careers in Women's Health Directors

BACKGROUND

Increasingly, national programs and leaders are looking at interdisciplinary collaborations as essential to future research. Twelve years ago, the National Institutes of Health (NIH) Office of Research on Women's Health (ORWH) developed and implemented the Building Interdisciplinary Research Careers in Women's Health (BIRCWH) K12 program to focus on interdisciplinary mentored career development for junior faculty in women's health research.

METHODS

We applied a mixed-methods approach using an electronic survey and in-person presentations and discussions to understand best practices and lessons learned for interdisciplinary mentoring across BIRCWH K12 program leaders.

RESULTS AND CONCLUSIONS

We received responses from all 29 active BIRCWH programs. Factors associated with success included ensuring sufficient protected time for regular (weekly or biweekly) mentoring; mentors promoting the research independence of the Scholar; a team mentoring approach, including career as well as content mentors; and explicit and clear expectations outlined between the Scholar and mentor. The majority of programs conduct formal evaluations of mentorship, and 79% of programs offer training in mentorship for either Scholars, mentors, or both. This article presents program leaders' best practices, challenges, and lessons learned from mentoring junior faculty who are conducting women's health research, whether basic, clinical, behavioral, translational, or health services research, using an interdisciplinary mentoring approach.

Alteration in angiogenic and anti-angiogenic forms of vascular endothelial growth factor-A in skeletal muscle of patients with intermittent claudication following exercise training

The aims of this study were twofold: (1) to identify whether peripheral artery disease (PAD) patients had increased muscle concentration of angiogenic VEGF-A, anti-angiogenic VEGF₁₆₅b or VEGF receptor 1 (VEGF-R1) when compared with control subjects, and (2) to evaluate whether exercise training in PAD patients was associated with changes in muscle concentration of VEGF-A, VEGF₁₆₅b or VEGF-R1. At baseline, 22 PAD and 30 control subjects underwent gastrocnemius muscle biopsy. Twelve PAD patients were treated with supervised exercise training (SET) and underwent muscle biopsy after 3 weeks and 12 weeks of training and had sufficient tissue to measure VEGF-A, VEGF₁₆₅b and VEGF-R1 concentrations in skeletal muscle lysates by ELISA. Muscle concentrations of VEGF-A and VEGF₁₆₅b were similar in PAD patients versus controls at baseline. At both time points after the start of SET, VEGF-A levels decreased and there was a trend towards increased VEGF₁₆₅b concentrations. At baseline, VEGF-R1 concentrations were lower in PAD patients when compared with controls but did not change after SET. Skeletal muscle concentrations of VEGF-A are not different in PAD patients when compared with controls at baseline. SET is associated with a significant reduction in VEGF-A levels and a trend towards increased VEGF₁₆₅b levels. These somewhat unexpected findings suggest that further investigation into the mechanism of vascular responses to exercise training in PAD patients is warranted.

Angiogenesis in skeletal muscle precede improvements in peak oxygen uptake in peripheral artery disease patients

OBJECTIVE

Peripheral artery disease (PAD) is characterized by impaired blood flow to the lower extremities, causing claudication and exercise intolerance. The mechanism(s) by which exercise training improves functional capacity is not understood. This study tested the hypothesis that in PAD patients who undergo supervised exercise training, increases in capillary density (CD) in calf muscle take place before improvements in peak oxygen uptake (VO(2)).

METHODS AND RESULTS

Thirty-five PAD patients were randomly assigned to 12 weeks of directly supervised or home-based exercise training. Peak VO(2) testing and gastrocnemius muscle biopsies were performed at baseline and after training. CD (endothelial cells/mm(2)) was measured using immunofluorescence staining. After 3 weeks of directly supervised training, patients had an increase in CD (216±66 versus 284±77, P<0.01) but no increase in peak VO(2). However, after 12 weeks, peak VO(2) increased (15.3±2.8 versus 16.8±3.8, P<0.01), whereas in muscle, CD remained increased over baseline, but there were no changes in markers of oxidative capacity. Within subjects, CD was related to peak VO(2) before and after directly supervised training.

CONCLUSION

Changes in CD in ischemic muscle with training may modulate the response to training, and those changes precede the increase in VO(2).

Supervised exercise versus primary stenting for claudication resulting from aortoiliac peripheral artery disease: six-month outcomes from the claudication: exercise versus endoluminal revascularization (CLEVER) study

BACKGROUND

Claudication is a common and disabling symptom of peripheral artery disease that can be treated with medication, supervised exercise (SE), or stent revascularization (ST).

METHODS AND RESULTS

We randomly assigned 111 patients with aortoiliac peripheral artery disease to receive 1 of 3 treatments: optimal medical care (OMC), OMC plus SE, or OMC plus ST. The primary end point was the change in peak walking time on a graded treadmill test at 6 months compared with baseline. Secondary end points included free-living step activity, quality of life with the Walking Impairment Questionnaire, Peripheral Artery Questionnaire, Medical Outcomes Study 12-Item Short Form, and cardiovascular risk factors. At the 6-month follow-up, change in peak walking time (the primary end point) was greatest for SE, intermediate for ST, and least with OMC (mean change versus baseline, 5.8±4.6, 3.7±4.9, and 1.2±2.6 minutes, respectively; P<0.001 for the comparison of SE versus OMC, P=0.02 for ST versus OMC, and P=0.04 for SE versus ST). Although disease-specific quality of life as assessed by the Walking Impairment Questionnaire and Peripheral Artery Questionnaire also improved with both SE and ST compared with OMC, for most scales, the extent of improvement was greater with ST than SE. Free-living step activity increased more with ST than with either SE or OMC alone (114±274 versus 73±139 versus -6±109 steps per hour), but these differences were not statistically significant.

CONCLUSIONS

SE results in superior treadmill walking performance than ST, even for those with aortoiliac peripheral artery disease. The contrast between better walking performance for SE and better patient-reported quality of life for ST warrants further study.

CLINICAL TRIAL REGISTRATION

URL: http://clinicaltrials.gov/ct/show/NCT00132743?order=1. Unique identifier: NCT00132743.

Fear of injury with physical activity is greater in adults with diabetes than in adults without diabetes

OBJECTIVE

Physical activity is a cornerstone of treatment for diabetes, yet people with diabetes perform less moderate and vigorous physical activity (MVPA) than people without diabetes. In contrast, whether differences in walking activity exist has been understudied. Diabetes-specific barriers to physical activity are one possible explanation for lower MVPA in diabetes. We hypothesized that people with diabetes would perform less walking and combined MVPA and would be less likely to anticipate increasing physical activity if barriers were theoretically absent, compared with people without diabetes.

RESEARCH DESIGN AND METHODS

We surveyed 1,848 randomly selected rural Colorado adult residents by telephone from 2002 to 2004. Respondents reported weekly walking and MVPA duration and their likelihood of increasing physical activity if each of seven barriers was theoretically absent.

RESULTS

People with diabetes (n = 129) had lower odds of walking and MVPA than people without diabetes (walking: adjusted odds ratio 0.62 [95% CI 0.40-0.95]; MVPA: adjusted odds ratio 0.60 [0.36-0.99]; ≥10 vs. <10 min/week, adjusted for age, sex, BMI, and ethnicity). Respondents with diabetes reported fear of injury as a barrier to physical activity more often than respondents without diabetes (56 vs. 39%; P = 0.0002), although this relationship was attenuated after adjusting for age and BMI (adjusted odds ratio 1.36 [0.93-1.99]).

CONCLUSIONS

Although walking is a preferred form of activity in diabetes, people with diabetes walk less than people without diabetes. Reducing fear of injury may potentially increase physical activity for people with diabetes, particularly in older and more overweight individuals.

Exercise and type 2 diabetes: American College of Sports Medicine and the American Diabetes Association: joint position statement. Exercise and type 2 diabetes

Although physical activity (PA) is a key element in the prevention and management of type 2 diabetes mellitus (T2DM), many with this chronic disease do not become or remain regularly active. High-quality studies establishing the importance of exercise and fitness in diabetes were lacking until recently, but it is now well established that participation in regular PA improves blood glucose control and can prevent or delay T2DM, along with positively affecting lipids, blood pressure, cardiovascular events, mortality, and quality of life. Structured interventions combining PA and modest weight loss have been shown to lower T2DM risk by up to 58% in high-risk populations. Most benefits of PA on diabetes management are realized through acute and chronic improvements in insulin action, accomplished with both aerobic and resistance training. The benefits of physical training are discussed, along with recommendations for varying activities, PA-associated blood glucose management, diabetes prevention, gestational diabetes, and safe and effective practices for PA with diabetes-related complications.

Relationship between leg muscle capillary density and peak hyperemic blood flow with endurance capacity in peripheral artery disease

The aim of this study was to determine if skeletal muscle capillary density is lower in patients with peripheral artery disease (PAD) and if capillary density relates to functional limitations. PAD patients with intermittent claudication (IC) have a decreased exercise tolerance due to exercise-induced muscle ischemia. Despite the apparent role diminished arterial flow has in this population, the degree of walking pain and functional limitation is not entirely explained by altered hemodynamics of the affected limbs. We hypothesized that skeletal muscle capillary density is lower in PAD and is related to the functional impairment observed in this population. Sixty-four patients with PAD and 56 controls underwent cardiopulmonary exercise testing and a gastrocnemius muscle biopsy. A subset of these patients (48 PAD and 47 controls) underwent peak hyperemic flow testing via plethysmography. Capillary density in PAD patients was lower compared with controls (P < 0.001). After adjustment for several baseline demographic imbalances the model relating capillary density to peak oxygen consumption (Vo(2)) remained significant (P < 0.001). In PAD subjects, capillary density correlated with peak Vo(2), peak walking time (PWT), and claudication onset time (COT). Peak hyperemic blood flow related to peak Vo(2) in both PAD and control subjects. PAD is associated with lower capillary density, and capillary density is related to the functional impairment as defined by a reduced peak Vo(2), PWT, and COT. These findings suggest that alterations in microcirculation may contribute to functional impairment capacity in PAD.

Assessment of functional status and quality of life in claudication

BACKGROUND

Treadmill walking is commonly used to evaluate walking impairment and efficacy of treatment for intermittent claudication (IC) in clinical and research settings. Although this is an important measure, it does not provide information about how patients perceive the effects of their treatments on more global measures of health-related quality of life (HRQOL).

METHODS

PubMed/Medline was searched to find publications about the most commonly used questionnaires to assess functional status and/or general and disease-specific HRQOL in patients with peripheral artery disease (PAD) who experience IC. Inclusion criteria for questionnaires were based on existence of a body of literature in symptomatic PAD.

RESULTS

Six general questionnaires and seven disease-specific questionnaires are included, with details about the number of domains covered and how each tool is scored. The Medical Outcomes Study Short Form 36-item questionnaire and Walking Impairment Questionnaire are currently the most used general and disease-specific questionnaires at baseline and after treatment for IC, respectively.

CONCLUSIONS

The use of tools that assess functional status and HRQOL has importance in both the clinical and research areas to assess treatment efficacy from the patient's perspective. Therefore, assessing HRQOL in addition to treadmill-measured walking ability provides insight as to the effects of treatments on patient outcomes and may help guide therapy.

Activity patterns of obese adults with type 2 diabetes in the look AHEAD study

PURPOSE

This study describes baseline physical activity (PA) patterns of individuals with type 2 diabetes mellitus (T2DM) enrolled in the multicenter Look AHEAD Study using an objective measure of PA (accelerometry).

METHODS

A total of 2240 participants (age = 59.0 ± 6.8 yr and body mass index (BMI) = 36.5 ± 6.0 kg·m−²) with T2DM provided data for this substudy. Participants were instructed to wear an accelerometer during waking hours for 7 d. Accelerometry data were analyzed to identify periods meeting the criteria of ≥3 MET·min−¹ for Q10 min(moderate- to vigorous-intensity PA (MVPA)) and ≥6 MET·min−¹ for ≥10 min (vigorous-intensity PA (VPA)). Self-reported PA was also assessed with a questionnaire. Accelerometry and self-reported PA data were compared across categories of BMI, sex, race, age, fitness, diabetes medication usage, and history of cardiovascular disease.

RESULTS

Self-reported PA was lower at higher levels of BMI, was higher in males, was lowest for African-American/black, and was positively associated with fitness. Multivariate analyses for accelerometer-measured MVPA and VPA showed that more PA bouts per day, minutes per bout, METs per minute, and MET-minutes were associated with higher fitness. For MVPA, bouts per day were higher in men, and METs per minute were higher in women. For VPA, bouts per day was positively associated with increasing age and differed by race/ethnicity. METs per minute were significantly lower at higher levels of BMI and in women. Diabetes medication usage and history of cardiovascular disease were not associated with patterns of PA examined.

CONCLUSIONS

Results provide information on factors that contribute to PA patterns in adults with T2DM when PA is assessed using both objective and subjective measures. These data may inform interventions to improve PA in adults with T2DM

Exercise and type 2 diabetes: the American College of Sports Medicine and the American Diabetes Association: joint position statement

Although physical activity (PA) is a key element in the prevention and management of type 2 diabetes, many with this chronic disease do not become or remain regularly active. High-quality studies establishing the importance of exercise and fitness in diabetes were lacking until recently, but it is now well established that participation in regular PA improves blood glucose control and can prevent or delay type 2 diabetes, along with positively affecting lipids, blood pressure, cardiovascular events, mortality, and quality of life. Structured interventions combining PA and modest weight loss have been shown to lower type 2 diabetes risk by up to 58% in high-risk populations. Most benefits of PA on diabetes management are realized through acute and chronic improvements in insulin action, accomplished with both aerobic and resistance training. The benefits of physical training are discussed, along with recommendations for varying activities, PA-associated blood glucose management, diabetes prevention, gestational diabetes mellitus, and safe and effective practices for PA with diabetes-related complications.

Diabetes and cancer: a consensus report

Epidemiologic evidence suggests that cancer incidence is associated with diabetes as well as certain diabetes risk factors and treatments. This consensus statement of experts assembled jointly by the American Diabetes Association and the American Cancer Society reviews the state of science concerning 1) the association between diabetes and cancer incidence or prognosis; 2) risk factors common to both diabetes and cancer; 3) possible biologic links between diabetes and cancer risk; and 4) whether diabetes treatments influence the risk of cancer or cancer prognosis. In addition, key unanswered questions for future research are posed.

Diabetes and cancer: a consensus report

Epidemiologic evidence suggests that cancer incidence is associated with diabetes as well as certain diabetes risk factors and diabetes treatments. This consensus statement of experts assembled jointly by the American Diabetes Association and the American Cancer Society reviews the state of science concerning 1) the association between diabetes and cancer incidence or prognosis, 2) risk factors common to both diabetes and cancer, 3) possible biologic links between diabetes and cancer risk, and 4) whether diabetes treatments influence risk of cancer or cancer prognosis. In addition, key unanswered questions for future research are posed.