Attività
Physical Activity, Obesity and Health
Cardiovascular risk factors and inflammation in obesity and overweight patients: effects of physical activity
Dario Giugliano,
Cattedra e Divisione di Malattie del Metabolismo, Centro di Eccellenza Cardiovascolare, Seconda Università di Napoli
Modern society has brought with it profound changes in lifestyle and an increased incidence of athrosclerotic
vascular disease. Body weights are on the rise, diets are becoming less healthy, and people are becoming increasingly sedentary,
resulting in elevations of blood pressure and metabolic alterations that increase atherothrombotic risk. In fact, obesity, insulin
resistance and diabetes are becoming a public health problem of epidemic proportions. The “metabolic syndrome” (also
referred as “syndrome X” or the “insulin resistance syndrome”) has emerged as an important cluster of risk
factors for athrosclerotic disease. Common features are central (abdominal) obesity, insulin resistance, hypertension, and dyslipidemia
(high triglycerides, low high-density lipoprotein cholesterol, and small atherogenic low-density lipoprotein particles). Insulin
resistance is thought to be a key feature, as there are interesting parallels between the metabolic syndrome and type 2 diabetes.
Abdominal obesity is associated with insulin resistance and hypertension; hypertension is frequently associated with insulin
resistance and other features of the metabolic syndrome.
All the parameters included in the diagnosis of the metabolic syndrome are associated with elevated levels of C-reactive protein
(CRP), an easily measured inflammatory biomarker that has been proven to be a strong, independent predictor of both incident
diabetes and incident cardiovascular disease. Moreover, obesity, insulin resistance and diabetes are associated with a proinflammatory
state, which in turn is associated with increased cardiovascular risk. In the apparently health women who participated in the
Women’s Health Study those with the metabolic syndrome had significantly worse cardiovascular event-free survival than
did those without the metabolic syndrome. Recent evidence from the Finnish Diabetes Prevention Study and US Diabetes Prevention
Program suggests that even modest lifestyle interventions can have a major impact in decreasing the risk for diabetes in glucose-intolerant
individuals. Physical activity, weight loss and diet favourably affect components of the metabolic syndrome at least in relatively
short term. Although proper management of the individual abnormalities of this syndrome can reduce morbidity and mortality,
it is likely that a more integrated strategy provides better outcomes. We have also shown that a long-term (2 years) multidisciplinary
program aimed to reduce body weight through lifestyle changes in obese women was associated with reduction of insulin resistance
and increased adiponectin concentrations. Because adiponectin possesses anti-inflammatory properties and improves glucose tolerance,
hypoadiponectinemia may contribute to the low-grade inflammation and the insulin resistance that characterize human obesity.
Thus, the increased cardiovascular risk of obese persons may be seen as the result, at least in part, of increased inflammatory
stimuli and decreased anti-inflammatory mechanisms.
