IJCS | Volume 33, Nº2, March / April 2020

128 Araújo & Aras Junior Therapeutic adherence and resistant hypertension Int J Cardiovasc Sci. 2020; 33(2):121-130 Original Article follow-up. 5,10 All of these variables were analyzed. However, there was no statistical significance for any of them as contributors to poor adherence, possibly because it is a cohort population with high cardiovascular risk and poorly diversified ethnic profile. The number of medications used may also have an impact on the degree of therapeutic adherence, 5,10 which was confirmed in this study, since the group with poor adherence used a significantly higher number of antihypertensive drugs. It is important to consider this finding when making prescriptions, as the use of tablets with drug combinations may be an effective strategy to improve adherence. In addition, emphasizing the need to change lifestyle, consider switching the drug class or increasing the dose of some drug already used—always considering the risk of developing adverse effects when increasing the dose — may be better for therapeutic adherence than just adding more drugs to the patient’s prescription. There is evidence that poor therapeutic adherence is one of the main obstacles to pressure control. 3,4,10,12 Therefore, patients with greater adherence tend to have lower pressure levels and greater BP reductions. 11,12 In this sample, it was found that, regardless of the degree of adherence, most individuals did not have good BP control, with no statistical difference between the groups. Even so, an expected trend can be identified in the groups: of the individuals with controlled BP, most are part of the group that has good adherence, whereas of the individuals with uncontrolled BP, most are part of the group with poor adherence. The absence of BP control in a large part of the population with poor adherence is expected. 3,4,10 However, in the group with good adherence, poor BP control was not expected. This can be explained by the low sensitivity of the Morisky test — only 43.6% — which, despite being the most used method in Brazil to quantify adherence to antihypertensive therapy, facilitating the comparison between studies, may not be the ideal one. 4,10 Thus, considering that patients with poor BP control have lower chances of having good therapeutic adherence, 12 patients classified by Morisky test as having good adherence could possibly have poor adherence. Therefore, Morisky test cannot be considered efficient to relate BP control to the patients’ posture as for taking their medications. 12 In addition, the high rate of poor BP control in the group with good adherence can also be explained by the fact that it is a group of individuals already very severe, so the pathophysiology of the disease itself makes it difficult to control BP levels even in those patients who follow the therapeutic scheme appropriately. Thus, it remains controversial in this population whether the adequate use of medications is as determining for the control of BP in severe patients as it would be for patients with nonresistant SAH. Not only is adherence important for controlling BP levels, but also the use of appropriate therapy – to the extent that, when inappropriate, it is indicative of pseudoresistance. In this sample, most of the patients used the combination of thiazide diuretic + ACE/ARB + CCB, but a considerable percentage did not use this combination, which is worrying, as they are patients with severe SAH seen at a reference clinic. Correct diagnosis of RH requires verification of adherence to treatment, 11 since poor adherence with uncontrolled BP will lead to unnecessary tests and modifications of prescription. 10 Despite the difficulty of controlling all causes of pseudoresistance to exclude cases of apparent RH 2 , the presence of pseudoresistance can be estimated. In this sample, patients with pseudoresistant SAH were identified from the evaluation of therapeutic adherence by the Morisky test, the therapeutic regimen used and ABPM. An estimated 28% of pseudoresistance in an outpatient clinic specialized in severe hypertension raises some questions about the way these patients are being monitored and the criteria for staying in a tertiary care service. Therefore, considering the results found, adherence to antihypertensive therapy can be increased by instructing patients on the importance of taking medications — ensuring that they have understood it —and by drawing strategies with the patients and their family to help them remember to take the medications properly. In addition, investigating possible adverse effects and discomfort with the use of medications is critical in order to, if necessary, change the drug or make dose adjustments to prevent the patient from discontinuing the medication on their own. Prescription of combined drugs in a single tablet also appears to be an effective strategy to improve adherence, as well as the judgment of the need to introduce another drug into the prescription, as this may compromise adherence to the entire prescription. The lack of data on pill counts or evaluation of serum levels of drugs brings a limitation to data analysis, especially considering that the Morisky test presents a sensitivity of only 40.3% for the evaluation of therapeutic adherence. Within the sample, no cases