Doctors’ views and strategies to improve patients’ adherence to medication

Non-communicable diseases (NCDs) are the leading causes of death across the world [1, 2], these including cardiovascular disease, cancer, chronic respiratory diseases, and diabetes. This fact represents a great threat to socioeconomic development given that more than 70% of all deaths globally and 80% of deaths in lowand middle-income countries are attributed to NCDs [2]. In 2013, the World Health Organization (WHO) adopted a target of 25% reduction in mortality from NCDs by 2025 [2]. In the European Union, approximately 550,000 people die prematurely each year from NCDs [3], while in Greece, 38% of deaths are attributed to diseases of the circulatory system, 25% to cancer, 20% to respiratory diseases, and 1.85% to diabetes [4]. Morbidity and mortality from these diseases can be avoided by a healthier lifestyle, disease prevention, and medication adherence. The 2018 OECD report [5] states that the health system’s resilience, more efficient spending policies, and long-term sustainability can be supported by adopting better strategies aiming at improvements in medication adherence. Cardiovascular diseases (CVDs) are the main type of NCDs, including heart disease, stroke, hypertension, congestive heart failure, and arteriosclerosis, most of them being associated with metabolic syndrome [6]. Despite the existence/implementation of effective therapies, cardiovascular outcomes still remain suboptimal [7–9]. Previous studies [10–17] have documented the relationship between insulin resistance and CVDs, taking into consideration other confounding factors such as body mass index [18–20], smoking, hypertension, high-density lipoprotein (HDL), and low-density lipoprotein (LDL) cholesterol. The 10-year financial crisis and the current COVID-19 pandemic have had a significant impact on the functioning of the health systems, highlighting the need for more effective and efficient management, at the same time ensuring equity and access to new therapies [21]. Adherence is an important factor in the effectiveness of long-term therapy and is defined by the WHO as “the extent to which a person’s behavior-taking medication, following a diet, and/or executing lifestyle changes corresponds with agreed recommendations from a health care provider” [22, 23]. According to Kravitz et al. [24], non-adherence to medication for cardiovascular diseases has been estimated to be higher than 60%. Self-assessed adherence in patients with coronary heart disease is less than 40% for the combination of aspirin, β-inhibitor, and a lipid-lowering agent in both short-term and cohort studies [25]. According to the Ascertaining Barriers for Compliance (ABC) Project, nonadherence in Greece is as high as 50% [26]. The period that follows immediately after discharge from the hospital is one linked to a high risk of medication non-adherence. Nearly one out of four patients is partially or completely non-adherent to treatment received after discharge from the hospital [27]. Concerning hypertensive patients who take just one medication as prescribed, 50% will stop taking antihypertensive medications within 6–12 months and only about 40% will continue statin treatment for 2 years for acute coronary heart disease [25, 28]. Medication adherence obviously greatly affects the effectiveness of treatment and, consequently, health outcomes, and patients’ quality of life [29]. Early non-adherence to treatment leads to a significant reduction in life expectancy by 1 year after hospitalization in myocardial infarction [27]. Secondary non-adherence (non-adherence to instructions or non-adherence to the prescription) has been shown to lead to increased mortality and hospitalization rates, plus additional costs [30–33]. * John Yfantopoulos yfantopoulos@gmail.com