To disclose risk factors of incident aortic stenosis (AS) and progression of established AS. A prospective cohort study. The Tromsø Study, a population based health survey. Over a 14 years span we performed three repeated echocardiographic examinations (1994, 2001 and 2008) of a random sample of initially 3,243 participants. Data from the only hospital serving this population were included in the follow up. Throughout the study 132 participants were diagnosed with incident AS, defined as mean aortic valve gradient ≥15 mmHg. Cox proportional hazards regression disclosed age (HR 1.11, 95 %CI 1.08-1.14), systolic blood pressure (BP) (HR 1.01, 95 % CI 1.00-1.02), active smoking (HR 1.71, 95 % CI 1.09-2.67), and waist circumference (HR 1.02, 95 % CI 1.00-1.03) as independent predictors of incident AS. Analysis of risk factors for progression of AS disclosed a higher mean aortic gradient at first measurement (p = 0.015), weight (p = 0.015), a low haemoglobin (Hgb) (p = 0.030) and high density lipoprotein (HDL) (p = 0.032) as significant independent predictors. Age, systolic BP, smoking and waist circumference were independent predictors of incident AS, whereas cholesterol was not. Mean aortic gradient at first measurement, weight, an elevated HDL and low Hgb increase the progression rate of the disease. Our data indicate that calcific aortic valve disease is a distinct pathophysiological process, with age, smoking and "wear and tear" of the valve being major contributors to the disease development.