Regular exercise and SCORE risk in obese type 2 diabetic patients Autor: Milan Tatić Mentor: Prof. dr Slobodan Antić

Introduction Physical activity has been regarded as benefitial since classical Greek civilization. Its therapeutic properties in diabetes were recognized in the early 20th century, and starting from Joslin et al., regular exercise has been convincingly demonstrated to provide many valuable health benefits in type 2 diabetic patients. It was observed not only to improve glycoregulation, but also to favorably modify other components of the metabolic syndrome, such as hypertension, dyslipidemia and central obesity.

Aim Investigate:

The Systematic Coronary Risk Evaluation (SCORE) model was chosen as a tool in this study for its numerous adventages compared to several similar models. It is derived from a large dataset of prospective European studies and predicts fatal atherosclerotic cardiovascular events over a ten year period. The risk estimation is based on gender, age, smoking, systolic blood pressure and either total cholesterol or the cholesterol/HDL ratio. The treshold for high risk based on fatal cardiovascular events is defined as ≥ 5%, instead of the previous ≥ 20% using a composite coronary endpoint. It not only offers the possibility to calculate the relative risk, but provides the possibility to project the risk to age 60, which may be of particular importance for significantly younger adults with unhealthy risk profile

Subjects and methodes

Procedures A detailed medical evaluation was performed at baseline, including an exercise stress test to assess cardiorespiratory fitness and help identify, if present, abnormal heart rate, abnormal blood pressure responses and previously undiagnosed ischemic heart disease.

Aerobic exercise programme was conducted following previously published guidelines and lasted for six months. The supervised programme consisted of at least 3-5 sessions of continuous and moderate aerobic exercise per week, of the average duration for minutes and at the workload corresponding to 50-75% of maximal heart rate. Intensity, duration and number of sessions were gradually increased uring the follow-up period.

Each session began with a warm-up period, which consisted of 5-10 minutes of lower aerobic activity and 5-10 minutes of stretching, and ended with a cool-down period of 5-10 minutes of less intense activity. The main part of each session consisted of minutes of brisk walking at the beginning of the programme, its duration gradually increased for 5-10 minutes each week until the desired duration of minutes has been attained.

Outcome measures Physical activity index Cardiovascular profile Oxidative stress-defense parameters

Statistical analyses Data were analyzed using statistical software Jandel SigmaStat® for Windows Version 2.0. Student`s T-test and non-parametric Mann-Whitney Rank Sum Test were used when appropriate and data were expressed as means ± SD or medians with range in parentheses. Parameters were correlated using simple linear regression test. A P value of less than 0.05 was considered statistically significant

The level of average daily physical activities, as estimated using Physical activity index, progresivelly increased during the study period non only in the whole diabetic group, but both in low-risk and high-risk subjects (P<0.001), and was followed with reduced SCORE risk, significant, however, only in high-risk subgroup from baseline to 3 and 6 months (P<0.01) Results Physical activity index and SCORE risk

Cardiovascular profile Regular exercise markedly reduced the majority of examined cardiovascular risk factors during the study period not only in all diabetics, but in both diabetic subgroups as well, i.e. both in low-risk and high-risk patients. However, the benefits of exercise on the majority of examined parameters became more evident in low-risk subgroup, compared to high-risk subgroup from baseline to 3 months.

Oxidative stress - defense parameters Significant improvement in oxidative defense was observed not only in all diabetics, but in both low-risk and high-risk diabetic subgroups as well, as demonstrated for significantly higher glutathione (P<0.01 and P<0.001, respectively) and markedly lower (P<0.001 and P<0.05, respectively) plasma malondialdehyde from baseline to 6 months, as well for significantly higher (P<0.01) catalase in low-risk subgroup and markedly higher sulphydryl groups in high-risk subgroup (P<0.05).

Oxidative stress - defense parameters Glutathione was significantly (P<0.05) lower in SCORE ≥ 5% subgroup at baseline, but the difference was not significant after 6 months of exercise. At baseline, however, it significantly correlated with physical activity index within both SCORE < 5% (P<0.001, R=0.95) and SCORE ≥ 5% (P<0.001, R=0.99) diabetic subgroups.

Discussion The aim of the present study was to investigate the effects of aerobic exercise programme Brisk walking has been already recognized as the prefered mode of aerobic exercise, at least untill the physical fitness got improved and the patient became familiar with the sensations associated with aerobic training. It was also concidered the most appropriate tool to perform regular exercise in group, and the most safe aerobic activity in order to prevent potential metabolic complications and orthopedic injuries. Significant increase in average daily physical activities, expressed as Physical activity index, was observed during the whole study period in previously sedentary, but motivated, type 2 diabetics, therefore clearly suggesting the importance of supervised nature of exercising, at least in the early stages of the programme.

Conclusion Regular and structured programme of moderate aerobic physical activity, prescribed following previously published guidelines and performed under supervision, is appropriate and benefitial in improving overall cardiovascular risk factors profile and reducing oxidative stress in previously sedentary, obese type 2 diabetic patients, who are highly motivated to become physically active.

THANKS FOR YOUR ATTENTION!!!