IS ANTIHYPERTENSIVE TREATMENT PROTECTIVE IN ELDERLY FRAIL PATIENTS? EVIDENCE FROM AN ITALIAN REAL-WORLD POPULATION

Abstract

Objective: Randomized clinical trials have shown a protective effect of the antihypertensive therapy on cardiovascular outcomes and all-cause death extending to elderly patients. Evidence is limited in frail old patients with a short life expectancy who have normally been excluded from trials. Aim of our study was to assess whether adherence to antihypertensive drugs is accompanied by a reduced risk of death and cardiovascular events in frail vs non-frail elderly individuals based on different life expectancies. Design and method: We identified from the Lombardy database the 1,183,201 residents aged >=65 years who had >=3 prescriptions of antihypertensive drugs between 2007–2009. A nested case-control design was applied. Cases were the cohort members who died or had hospital admission for cardiovascular events until 2012. Logistic regression was used to model the association between adherence with antihypertensive treatment and outcome risk. The analysis was separately performed in four clinical categories, i.e. patients with a good, medium, poor, and very poor clinical status, as assessed by a score prognostic index (MCS) based on 34 weighted cardiovascular and non-cardiovascular morbidities that has been shown to be a more sensitive predictor of death and hospitalization in the Italian population than other largely used scores. From the good to the very poor clinical status, the 6-year death probability increased from 12 to 58%. Results: Compared with patients with very low adherence to antihypertensive treatment, those with high adherence exhibited a lower risk of all-cause mortality in each clinical status. The reduction in risk was 52%, 49%, 43% and 34% in the good, medium, poor and very poor clinical categories, respectively. Adherence to antihypertensive drug treatment was also associated with hospitalization for cardiovascular diseases among patients with a good or medium clinical status. In contrast, there was no evidence that drug adherence affected the risk of cardiovascular disease in patients with a poor or very poor clinical status. Conclusions: Adherence to antihypertensive treatment reduced the risk of death in frail elderly patients. This was not the case for the risk of cardiovascular hospitalization. More studies are needed to understand the reason for this discrepancy.