Common risk factors associated with acute myocardial infarction: Population-based studies with a focus on gender differences

Abstract: The overall aim of this thesis was to explore how the risk for AMI, and the associations between several of its risk factors, differs by gender. Information was collected from four Swedish cohorts: one patient cohort from Skara (1992-1993, n=1149) and three population-based cohorts, i.e. from Skara (1993-1994, n=1109), Vara (2001-2004, n=1811), and Skövde (2003-2005, n=1005). Participants were examined and filled out questionnaires regarding lifestyle and health. An interaction between gender and type 2 diabetes was found with regard to the risk of fatal AMI, showing that the impact of type 2 diabetes on AMI is greater in women than in men. Gender differences were also found in several AMI risk factors and in the associations between these risk factors: • Basal salivary cortisol was generally higher in women than in men (and in older subjects in general as compared to younger). • Low morning salivary cortisol and low diurnal variation of cortisol was associated with high waist-hip ratio solely in women. • Leisure time physical activity was negatively associated with insulin resistance and obesity in both men and women. However, the association with regard to insulin resistance and leisure time physical activity was stronger in women than in men. • Occupational physical activity was positively associated with insulin resistance and general and abdominal obesity in women only. • Factor analysis of AMI risk factors yielded three identical clusters in both genders: a “metabolic factor”, a “vitality factor”, and an “addiction factor”. However, these factors partly differed in their association with left ventricular hypertrophy, with significant associations with regard to the metabolic factor in both genders, and to the addiction factor in men. These findings show that gender differences with regard to AMI are present both in the risk of developing the disease and in how different risk factors for the disease interrelate. Thus, this thesis highlights the need for considering and addressing potential gender differences at all stages of preventive and interventional work aiming to reduce the burden of AMI.