Uncontrolled hypertension increases the risk of stroke
According to a study published in the European Heart Journal, patients with hypertension who do not take their antihypertensive medication when they should have an increased risk to stroke and of dying than those who take their medication correctly. It is known that the main risk factor for stroke is uncontrolled high blood pressure and also that reducing hypertension decreases both the risk of ischemic stroke and hemorrhagic stroke.
The study was conducted by scientists from Finland and University College London, UK and involved the analysis of 73 527 patients with hypertension. It was showed that patients who did not adhere to treatment had a 4-fold increased risk to die from stroke in the second year after the first prescription of medication and 3 times higher risk in the tenth year, compared with patients taking antihypertensive treatment correctly. It was also shown that patients who died of stroke had a 5.7-fold higher risk than adherent patients. Also, patients who did not got the medication correctly were more likely to be hospitalized after stroke (risk was 2.7 times higher than in patients who adhered to treatment).
Dr Kimmo Herttua, a senior fellow in the Population Research Unit at the University of Helsinki, Finland, and first author of the study, said the study underscores how important it is to take the antihypertensive drugs in order to minimize the risk of serious complications such are fatal and non-fatal stroke. He added that non-adherent patients had a higher risk even 10 years before to suffer from a stroke and that there is a dose-response relationship.
The researchers could find out if patients were adherent to treatment by tracking the number of prescriptions issued for them every year. Those who were taking the treatment correctly more than 80% of the time were declared adherents while non-adherents patients were divided into two categories: intermediate adherence (adherence 30-80%) and low adherence (less than 30%). Dr Herttua said they also took into account the fact that patient adherence can change over time and that every year they analyzed the association between treatment adherence and fatal stroke and non-fatal. The study also took into account the classes of antihypertensive drugs. It was found that among patients taking drugs that affect the renin-angiotensin system (such as converting enzyme inhibitors) combined with diuretics or beta-blockers, those who were non-adherent had a 7.5 times higher risk of death and a 4-fold increased risk of hospitalization compared with patients who took the medication correctly.