Unbalanced risk factors, could compromise the effectiveness of physical training in patients with intermittent claudication?

AIM: The correction of atherosclerotic risk factors is the unavoidable assumption to assure the maximal effectiveness and duration of the results of any therapeutic intervention (pharmacological and surgical) for the treatment of intermittent claudication. Aim of this study has been to verify if the presence/absence of risk factors and the degree of their correction could compromise the responsiveness of claudicant patients to the supervised physical training. METHODS: Initial (IDC), absolute (ACD) claudication distance, and recovery time (RT) have been measured by maximal treadmill exercise in 74 claudicants. The measurements have been repeated after 18 days of supervised physical training consisting of a daily walk reaching either a distance goal of 1-2 km or a time goal of at least 30 min. The working load of each single training session has been tailored at 60-70% of the ACD measured by a non-maximal treadmill exercise. The patients' cohort has been stratified in 7 groups and 18 sub-groups (no smokers, smokers in the past, still smokers, no-diabetics, well balanced and unbalanced diabetes, absent, well balanced and unbalanced hypercholesterolemia, normal weight, over weight and light obesity, hypertensive and no-hypertensive, with and without previous myocardial infarction and TIAs or stroke). The mean and standard error of ICD, ACD and RT before and after 18 days of physical training have been calculated and compared with Student's t test in each group and sub-group. On the data before and after training of ICD, ACD and RT of each group of risk factors the multivariate analysis of the variance has been carried out by analysis of variance (ANOVA). All the analyses were considered significant when the P value was less than 0.05. RESULTS: ICD values increased from 55.12 to 121.86 m, ACD from 103.16 to 191.58 m, RT reduced from 204.04 to 87.46 s, confirming the relevant (P<0.0001) effectiveness of supervised physical training on the walking capacity of claudicant patients. The comparison between the deltas (value after minus value before) of each sub-group did not show any significant difference. The multivariate ANOVA of before and after ICD ACD and RT of each risk factor groups showed values relevantly lesser than 0.05, indicating that risk factors did not influence the result of physical training. CONCLUSIONS: The supervised physical training is confirmed as an effective tool for the treatment of claudicant patient. We did not find any significant difference in the response to the programme related with the presence, absence or balance degree of risk factors, and we conclude that physical training effectiveness is independent from the their presence, absence or balance degree. This statement is very important because highlights the physical training as the only therapeutic tool for peripheral arterial disease (PAD) independent from the results of the risk factors' treatment.

Effectiveness and costs of a short-course supervised training program in claudicants: proposal for a shared protocol with aerobic working load.

AIM: The purpose of this study was to assess the costs and effectiveness of a short-course physical training program, consisting of an aerobic protocol with clearly defined working loads in each single training session, in patients with intermittent claudication (IC). METHODS: Initial (ICD), absolute (ACD) claudication distance, and recovery time (RT) have been measured by maximal treadmill exercise in 74 claudicants. Ankle brachial index (ABI) has been measured too. Measurements have been repeated after 18 days of supervised physical training consisting of a daily walk reaching either a distance goal of 1-2 km or a time goal of at least 30 min. The working load of each single training session has been tailored at 60-70% of the ACD measured by a non-maximal treadmill exercise. RESULTS: ICD increased from 56.2 (+/- standard deviation/+/- standard error: 35.3/4.1) to 123.9 (66.5/7.7); ACD increased from 104.8 (49.8/5.8) to 195.1 (81.7/9.5) and RT reduced from 201.2 (98.3/11.4) to 85.8 (43.6/5.1), with P<0.0001 for all parameters. We analyzed separately patients with moderate (M-CL) and severe (S-CL) claudication, and found significant improvements in both groups. The Ds (post-training value minus pretraining value) were: ICD 89.6 (59.9/10.9) in M-CL and 50.2 (29.9/4.6) in S-CL; ACD 102.8 (66.8/11.6) in M-CL and 80.1 (41.5/6.4) in S-CL; RT -98.7 (86.9/15.1) in M-CL and -128.5 (88.1/13.7) in S-CL, with P<0.0001 for all parameters. The differences between M-CL and S-CL were significant only for ICD (P=0.0003) and ACD (P<0.05). ABI showed an increasing trend, which was statistically significant (P<0.001), but clinically irrelevant. The protocol cost was 4179 Euro (average cost 46.30 Euro to walk one additional meter). CONCLUSION: Supervised physical training is confirmed to be an effective tool for the treatment of IC, and the proposed short-course protocol gave the same improvements as the longer ones while reducing the costs. The proposed procedure for tailoring the working load of a single session identifies clearly the working load, near maximal pain but avoiding the risk of inflammatory activation.

Acute impairment of the endothelial function by maximal treadmill exercise in patients with intermittent claudication, and its improvement after supervised physical training.

AIM: The aim of this study was to determine the effects of maximal exercise and of physical training on endothelial function (EF) of patients with intermittent claudication (IC). METHODS: EF, assessed by ultrasonography of the brachial artery, has been measured in 22 male patients with IC before (pre-exercise EF) and after (postexercise EF) maximal treadmill test. Absolute claudication distance (ACD) and ankle brachial index (ABI) have been measured too. The measurements have been repeated after 18 days (3 times weekly, for 6 weeks) of supervised physical training. RESULTS: Before training, the pre-exercise EF was 7.6+/-2.94 and postexercise EF 5.28+/-3.3 (-33.2%) (P<0.01). After training, the pre-exercise EF was 10.3+/-4.04, whilst postexercise EF was 7.79+/-2.56 (-18.97%) (P<0.01). The differences between the pre-exercise value before and after training and between the postexercise value before and after training were significant (P<0.01). ACD and ABI after training increased respectively from 93.95 to 166.55 m and from 0.67 to 0.71 (P<0.001). CONCLUSIONS: Endothelial dysfunction takes a relevant part in the pathophysiology of IC, with 2/3 of the patients showing an EF lower than the pathological cut-off. Maximal exercise worsens the EF, according to the trend associated with the acute inflammatory response. All these features suggest that physical activity in IC should not utilize the maximal working load, in order to avoid the high inflammatory activation and the acute complications of atherosclerotic plaque. The supervised physical training, besides confirming itself as the most effective means to increase the walking ability, also proved to be able to improve the EF of these patients, as described about other diseases. It is probable that moderate hemodynamic stress reduces the levels of the inflammatory markers and increases the flow-mediated vasodilation through an ischemic preconditioning. The increased walking ability, associated with the improvement of EF could improve the heavy systemic outcome of claudicant patients, as it has been demonstrated in patients with coronary heart disease. Further prospective survival studies on cardiovascular outcomes of trained claudicant patients are needed.