Ground work of a program for primary prevention of cardiovascular diseases

Background: Primary prevention represents the best treatment for CV diseases, in particular among high-risk patients. High levels of cardiorespiratory fitness were associated with an increase of the proven risk factors1 and a lower risk of having carotid atherosclerosis 2. Moreover, among community dwelling, middle aged adults, a higher daily step count at 5 year follow-up than at baseline was associated with better insulin sensitivity. This effect seems to be largely mediated through lower adiposity, and time spent sedentary predicts higher levels of fasting insulin independent of the amount of time spent at moderate/vigorous intensity activity levels3,4. However, even among younger patients, reduction of CV-risk with physical activity, diet and other non-pharmacologic approaches is frequently underestimated. We started a project of in-hospital physical activity program for primary prevention among high-risk patients. Aims: To evaluate if a 3-months in-hospital course of physical activity can improve metabolic and vascular parameters in high-risk patients. Methods: We enrolled 24 consecutive, high-risk patients with no history of prior acute vascular events, defined as acute coronary syndromes, prior stroke/TIA and peripheral artery disease. For each patient we evaluated full history and drugs used. Each patients underwent to a complete evaluation before physical activity with treadmill stress-test, resting echocardiography, FMD, supra-aortic trunks with intima-media thickness (IMT) evaluation, fasting glucose/ insulin (HOMA index) and total cholesterol, LDL, HDL and triglyceride dosage. Patients with positive stress test were excluded from the training. After a three-months training (three times a week for an hour), we evaluated again the patients with the same tests done at enrollment. T-test for repeated measures and Wilcoxon’s sign rank test were used to assess differences among patients. Results: At baseline, patients had a mean age of 56 years, with a M:F ratio of 2:1, a mean weight of 100.5 kg (±4.70). 16.7% of the sample had smoke attitude, 83.3% were hypertensive, 58.3% had familial history of CV pathologies, 87.5% were diabetics. Mean BMI was estimated at 34.5 (±1.48) g/m2 with a mean Framingham risk score of 12% (13% corrected). Mean of HOMA index was 9.43 (±2.28); mean FMD was estimated at 12% (±2%); mean indexed left ventricle mass was estimated at 108 g/sqm (±7.4 g/sqm). At this moment, only 5 patients have completed 3-months course and are suitable for analysis. With paired-samples t-test we observed a significative reduction of BMI (2.6%, p\0.05), IMT (18%, p\0.05), HOMA-index (37%, p\0.05) and left ventricle mass (16.5%, p\0.05). We also observed a significative increase in vascular reactivity, as assessed with FMD (117%, p\0.05). Framingham risk score index decreased of 50% (p\0.05). Discussion: An in-hospital primary prevention can allow a safe reduction of CV risk among high-risk, obese patients. We observed a reduction of global risk, as assessed with Framingham risk-score index, insulin resistance, endogenous NO production, carotid atherosclerosis and slight reversal of cardiac hypertrophy. These data represent a ground work to extend the program on larger cohorts. Conclusions: Primary prevention for CV diseases is based on reduction of modifiable risk factors, reducing individual risk. In addition to drugs, it is very important to change lifestyle. This highlights the importance of reducing sedentary time in order to improve metabolic health, possibly in addition to the benefits associated with a physically active lifestyle.