#2869 Arterial hypertension: do self-care and knowledge of the disease matter?
Authors: Roxo Maria Inês , Guerra Maria Manuel , Pepe Bruno , Birne Rita , Branco Patrícia , Dickson Jorge , Gaspar Augusta 
Published: May 2024

Abstract

Background and Aims
Arterial hypertension (HTN) is the main risk factor for cardiovascular disease, which is in turn the leading cause of mortality worldwide. An adequate blood pressure (BP) control depends not only on biological factors, but also on individual behaviour and health literacy. In this area, there is scarce evidence on the potential impact of the level of knowledge and self-care related to the disease. This study aims to measure and characterise these variables in a population of hypertensive patients.

Method
We developed a retrospective, multi-centre study among patients with HTN, with follow-up at the hospital (at the Nephrology Department) or in primary care. The patients were randomly selected by convenience sampling, between November 2022 and December 2023. With their informed consent, we collected demographical and clinical variables, and applied the Portuguese version of the Self-Care of Hypertension Inventory (SC-HI) and Hypertension Knowledge Test (HKT) questionnaires. The statistical analysis was performed using Microsoft Excel and SPSS. The study is still ongoing; we hereby present a preliminary analysis.

Results
To date, we have collected data from 75 patients; 48% were female, with a median age of 69 (IQR 23). The follow-up was carried out at the hospital in 63% (n = 47) of the patients. 54.6% (n = 41) were retired and 66.7% (n = 50) had finished high school or higher education. Most patients (94.7%) had at least one comorbidity; the most common were dyslipidaemia (57.3%), obesity (33.3%), chronic kidney disease (20%) and diabetes (16%). 25 patients (33.3%) met the criteria for polypharmacy and 69.3% had been diagnosed for over 10 years. The median score at HKT was 16 (IQR 3), out of a maximum of 21, and the median score at SC-HI was 65 (IQR 16), out of a maximum of 92. There were 4.3% of invalid answers, which were scored as zero for the final calculations. Using the Spearman correlation test, we found no significant association between the scores (p = 0.061). When analysing subgroups (Figs 1 and 2), the polymedicated patients scored higher on SC-HI but lower on HKT. Those with controlled BP scored lower on both scores. Patients with Hypertension-Mediated Organ Damage (HMOD) scored higher on SC-HI but lower on HKT, while the contrary happened in those with a more long-standing diagnosis.

Conclusion
We must start by recognising that this is only a preliminary and mainly descriptive analysis of the sample, whose size is not yet representative. Moreover, the complexity of the questionnaires might have influenced the results, as seen by the non-negligible percentage of invalid responses. Taking these limitations into account, some considerations should still be made. Firstly, the median scores show that we still have a long way to go to increase health literacy, especially if we consider the relatively high level of education of the sample. The percentage of patients with comorbidities and polymedicated is also worthy of mention. The results suggest that these complex patients are forced to take more attitudes towards self-care, but do not necessarily know more about their disease; the same happens in patients with HMOD. On the other hand, those with a more long-standing diagnosis seem to know more but not necessarily be more self-cautious. These results, together with the absence of association between the scores, suggest that we must educate patients both on the appropriate self-care and the rationale behind it (and not solely on one of them), in order to maintain lasting positive behaviours. Surprisingly, patients whose BP was controlled were actually less self-conscious and informed—they could possibly have less complex disease, as there are many confounding factors that influence BP control for which the results were not corrected. In conclusion, this study reinforces the complexity of this topic and the need to invest in its understanding; the completion of this investigation, as well as the development of further studies and better tools to evaluate self-care and knowledge, are undoubtedly necessary.