Doctoral defence: Sirje Sammul “Prevalence and risk factors of arterial hypertension and cardiovascular mortality: 13-year longitudinal study among 35- and 55-year-old adults in Estonia and Sweden”

On 14 June at 14:00 Sirje Sammul will defend her doctoral thesis “Prevalence and risk factors of arterial hypertension and cardiovascular mortality: 13-year longitudinal study among 35- and 55-year-old adults in Estonia and Sweden” for obtaining the degree of Doctor of Philosophy (in Medicine).

Supervisors:
Associate Professor Kersti Pärna, University of Tartu
Tenured Full Professor Margus Viigimaa, Tallinn University of Technology

Opponent: 
Associate Professor in epidemiology Axel C. Carlsson, Karolinska Institute (Sweden)

Summary
Arterial hypertension is a widespread disease that significantly increases the risk of cardiovascular morbidity and mortality. Early detection and a reduction of risk factors are important in the prognosis of arterial hypertension. 

The doctoral thesis investigated the prevalence of arterial hypertension and cardiovascular mortality   their risk factors among 35- and 55-year-old cohorts in 13-year follow-up study with two waves in Estonia and Sweden.  From risk factors, the focus was on psychosocial factors, personality traits, lifestyle factors, and health indicators.

The results of the study showed that the prevalence of arterial hypertension was significantly higher in Estonia than in Sweden after 13-year follow-up period. Significantly higher depressive mood and influence of negative stressful life events, but lower total quality of life prevailed in 35- and 55-year-old cohorts in Estonia and Sweden in both study waves. Compared to 55-year-old cohort without diagnosis of arterial hypertension, influence of negative stressful life events was significantly higher, but mastery significantly lower among 55-year-old adults with a diagnosis of arterial hypertension in Estonia, but not in Sweden. In total, nearly half of Estonian and Swedish men in the 55-year-old cohort died due to cardiovascular diseases, of them two thirds due to ischaemic heart disease during the 13-year follow-up period. Current smoking and higher plasma levels of interleukin-6 were main predictors of cardiovascular mortality. In Estonian study, several psychosocial and lifestyle factors, and health indicators showed independent association with arterial hypertension, but in the final regression model, only obesity predicted risk for arterial hypertension in 55-year-old cohort.

The results of the doctoral thesis can be applied in the prevention and reduction of arterial hypertension morbidity and cardiovascular mortality in Estonia. Interventions should be comprehensive, where in addition to lifestyle factors, psychosocial factors and personality traits should be screened early.