Health literacy is defined as the knowledge, skills, motivation, and ability to identify, understand, evaluate, and use health information in decision-making in care, disease prevention, and health promotion contexts to maintain or improve quality of life [1] . According to the World Health Organization (WHO) [2] , it encompasses the knowledge, motivation, and skills of a subject that enable him or her to access, understand, evaluate, and apply health information in order to form an opinion, make decisions in daily life for his or her health, prevent diseases, and promote his or her health to maintain or improve one’s quality of life throughout life.

Health literacy is recognized as a determinant of public health, a factor in effective population health management, individually and collectively, by empowering patients and strengthening their sense of self-efficacy [2 ] - [4] . It includes three dimensions: functional health literacy, communicative or interactive health literacy, and critical health literacy [5] . Indeed, functional health literacy refers to the search for and understanding of health information, which essentially refers to the general literacy of the subjects, i.e., their knowledge and skills in the fields of reading, writing, speaking, arithmetic, or computer skills. Communicative or interactive literacy involves interaction with the health care system and all health professionals: these are the skills needed to extract, understand, and distinguish health information from different sources and apply new information to changing circumstances. Finally, critical health literacy consists of making a judgment and evaluating the relevance of information obtained from different sources, then using it in a way that modifies one’s environment and situations that may impact one’s health [6] .

A low level of health literacy has negative consequences on individual and population health: higher incidence of risky behaviours, including a sedentary lifestyle, alcohol and tobacco consumption, an unbalanced diet, or risky sexual behaviours; the occurrence of chronic pathologies and decompensations with the need for emergency hospitalizations; erratic medical follow-up; poor medical understanding, etc. [7] . This finding is more pronounced in the elderly due to a decrease in faculties associated with aging [8] . A European study [3] reported that nearly half of adults do not have a sufficient level of health literacy to be fully independent, even though it has been shown that a poor level of health literacy is associated with the early development of chronic pathologies (diabetes, cancer, cardiovascular disease, etc.) [9] - [11] , which are more common in the elderly.

Palliative care is one of the main areas of treatment for these chronic pathologies with the aim of improving the quality of life of patients. They consist of caring for people suffering from life-threatening incurable diseases by relieving pain, symptoms of discomfort, and their suffering, and supporting them and their loved ones in difficult times, all this, in a holistic approach to care (physical, psychological, social, spiritual, etc.) [12] . Given that the participation of patients in health decision-making, especially in a palliative context, with the aim of becoming an actor in one’s own care plan, is one of the major axes of contemporary medicine [2] - [4] , it is essential to ensure their level of health literacy so that they are able to understand, evaluate and use health information on the different trajectories of care, dying and dying [13] .

In the context of palliative care, adequate patient health literacy helps to understand the care options and treatments available, promotes better communication with caregivers and allows care focused on the patient’s needs and expectations, hence the interest of this study, the objective of which was to analyze the health literacy profiles of patients followed at the Palliative Care Unit (PCU) of the National Hospital Center Hubert Koutoukou Maga University (CNHU-HKM) from Cotonou, Benin. The results could serve as a basis for strategies to improve communication and therapeutic education of palliative patients in their particular context.

The study revealed that more than 3/4 (76%) of respondents have a reliable general level of health literacy regardless of the dimensions (average total health literacy score ≤ 4) ( Table 2 ), which illustrates a certain informational vulnerability in this specific context of palliative care, while limited knowledge of health is consequently limited, posing a threat to health care outcomes, improved population health, and health equity [17] . Also, according to some authors [18] - [21] , in clinical departments (such as that of the Palliative Care Unit of the CNHU-HKM in Cotonou/Benin, the setting of the study), low health literacy is perceived as a risk factor for poor health and imperfect application of care advice. Better still, in public and community health, health literacy is seen as a personal and population asset that offers greater autonomy and allows for better control over health decision-making, thereby improving individual empowerment and action on the social determinants of health. In fact, health literacy is increasingly seen as a determinant of health [22] and high levels of health literacy can support a wide range of health-promoting actions, including personal behaviour change, health-promoting social actions, and influencing others to make good choices for their health [17] . Better still, Van Den Broucke and Renwart [23] believe that health literacy could act as a mediator of social inequalities and health behaviours.

The lowest average health literacy score was observed in functional health literacy (1.83 ± 1.51) ( Table 3 ), which may reflect significant difficulties in understanding health-related written or digital media. This corroborates the results of the work of Ishikawa et al. [24] , who showed that patients with chronic diseases (as is most often the case in palliative care, the specific context of the study) often have limited skills to understand written health materials. For Sorenson et al. [3] , functional health literacy remains the most fragile in contexts of vulnerability or low socio-educational level.

The mean critical health literacy score (1.94 ± 1.61) ( Table 3 ) was also low, showing a limited ability of the palliative patients surveyed to assess, filter, or question health information, which could impede their informed decision-making. According to Adegoke et al. [25] , critical health literacy is the weakest of the three components of health literacy. McCaffery et al. [26] evolve in the same paradigm as Adegoke et al. [25] , noting that critical health literacy remains difficult to develop, even in literate patients, because it requires increased reflective skills and cognitive autonomy. In contrast, communicative or interactive health literacy has a higher average score (2.88 ± 1.02) ( Table 3 ), indicating that respondents are relatively more comfortable in verbal or collaborative exchanges on health issues. This confirms the ideas of Paashche-Orlow et al. [27] , who believe that some patients, although they have reading difficulties, manage to compensate for their shortcomings partially through interactions with caregivers.

The results of the study showed a potential interdependence between the different dimensions of health literacy through a consistency in the proportions of low (≤4) and high (>4) scores observed ( Figure 2 ). This could be explained by the fact that since the assessment of health literacy begins with functional health literacy and that this is the foundation of basic skills in reading, comprehension and use of medical information, it is plausible that limitations at this level may hinder the development of the other two dimensions of health literacy (communicative or interactive health literacy and critical health literacy). This hypothesis fits perfectly with the study’s frame of reference, Nutbeam’s theory [6] that health literacy moves in hierarchical steps from basic understanding to critical engagement.

Palliative care patients under 60 years of age had significantly higher mean health literacy scores than those aged 60 years and older, highlighting a statistically significant influence of age (less than 60 years) on health literacy (p-values all less than 0.05 for all three dimensions of health literacy assessed) ( Table 6 ). These results highlight the influence of age on the understanding, interaction, and evaluation of health information, which confirms the observations made by Dignard [28] , who points out that age has a significant impact on health literacy, with a general trend towards a decline in health literacy skills with advancing age. Sorensen et al. [3] follow the same paradigm as Dignard [28] in finding that nearly half of adults do not have a sufficient level of health literacy to be fully independent. Better still, those particularly at risk of low health literacy are the elderly due to a decrease in faculties associated with aging [8] . A publication by the Institut National de Santé Publique du Québec (INSPQ) [29] reported that in Quebec, more than 60% of adults do not have a sufficient level of literacy to take adequate care of their health, and that this percentage is higher among the elderly.

The study notes that school-educated palliative patients have significantly higher average health literacy scores than those who are not in school ( Table 7 ), showing a statistically significant influence of educational attainment on health literacy scores (p-values all less than 0.05 for all three dimensions of health literacy assessed). These results are consistent with those of Sorenson et al. [3] , who show that education is one of the most powerful determinants of health literacy. An INSPQ study [29] reported that people with a low level of education were up to three times more likely to have insufficient health literacy.

In the study, the majority (72%) of the palliative patients surveyed expressed themselves in their mother tongues (Fon, Goun, Mina), which reflects the sociolinguistic reality of Benin ( Table 1 ). However, respondents who expressed themselves in French obtained average health literacy scores that were significantly higher than those who expressed themselves in national languages ( Table 9 ), which shows that the language of communication significantly influences health literacy scores (p-values all less than 0.001 for all three dimensions of health literacy assessed). The use of French, the dominant language in institutional and health communication media in French-speaking Africa, seems to confer a significant advantage in terms of health literacy. This finding corroborates the results of the study by Dray et al. [30] , which have shown that language barriers are a major barrier to accessing care and understanding health messages among immigrant or Francophone populations. For these authors [30] , health literacy is severely compromised when information materials are not adapted to the language or cultural context of patients. All this calls for linguistic adaptation strategies, particularly for audiences speaking in national languages, in order to guarantee equitable access to information in a multilingual context. The INSPQ [29] also recommends that culture, values, beliefs, and mother tongue be taken into consideration to ensure that the messages and formats of written material reach the target audience.

The study showed that the variable “sex” did not show a statistically significant influence on health literacy scores for any dimension (p > 0.05) ( Table 8 ). This lack of effect contrasts with the work of other authors such as Lechevallier [8] , who tells us that sex is not always a discriminating factor, especially when it is adjusted for other variables such as age, level of education, or mother tongue. On the other hand, a publication by the INSPQ [29] indicates that gender can influence informational preferences, search behaviours and the ability to understand certain media, particularly in relation to social roles. Finally, it was noted that the majority of respondents (16/25) were shopkeepers (44%) and housewives (20%). According to Clouston et al. [31] , people in manual or low-skilled occupations (manual workers, commercial employees, housewives) (such as these respondents) have significantly lower health literacy scores than managers or intellectual professions.

In sum, sociodemographic variables such as age, level of education, and language of communication have statistically significant influences on the health literacy of the palliative patients surveyed. These results are consistent with those obtained by Boumendil [32] , who highlights a heterogeneity in health literacy skills and a sensitivity to sociodemographic determinants (age, level of education, clinical experience) that significantly influence the scores obtained by the respondents. The verbatims illustrating the influence of the level of education, age, and language of communication on the various dimensions of health literacy (Tables V, VII, and X) extended and illustrated the statistical trends observed through the statistical tests carried out. This qualitative approach gives a human depth to the numerical results (quantitative analysis) by showing how skills are concretely translated into the way patients experience their relationship with medical information. It should therefore be stressed that this complementary approach does not modify the quantitative aspect of the study in any way: it is indeed an illustrative approach.

The evaluation of the level of health literacy of patients followed in the USP of the CNHU-HKM in Cotonou proved essential to understand the potential obstacles to therapeutic communication and the co-construction of end-of-life decisions. This study provided a nuanced picture of respondents’ health literacy profiles, revealing overall low to moderate scores with a predominance of difficulties in functional health literacy and critical health literacy, while interactive health literacy remained relatively preserved. The statistical analysis revealed a significant influence of age, level of education, and language of communication on the observed health literacy scores. Younger patients (under 60 years of age), those with a higher level of education, and those who speak French had higher health literacy scores with p-values of less than 0.01, respectively, for each of the dimensions tested.

These results show that health literacy, far from being a universal achievement, is dependent on structural, cultural, and linguistic inequalities. Health literacy is also considered a tool for intervention in prevention and health promotion, a tool to help public policies that have several fields of action: improving health communication, creating environments that are more open to people with lower skills, understanding the obstacles and factors to improve the population’s literacy levels, understand the links between health literacy and health inequalities [33] [34] . According to Van den Broucke [34] , improving the level of health literacy is a major public health issue if the population is to be able to take care of its health in the best possible way.

The results of the study call for an adaptation of information materials, educational approaches, and professional practices to the realities of patients in a palliative context. Beyond the simple diagnosis, this research highlights the urgency of developing contextualized, sustainable, and culturally appropriate interventions to promote better understanding and dignified support until the end of life. As an example, the design of a user welcome booklet for the USP of the CNHH-HKM of Cotonou translated into one of the most widely used mother tongues in Benin such as “Fon” and presenting the structure, its mode of operation, the rights and duties of caregivers, as well as the creation of a user welcome and information corner within the USP and animated in the main mother tongues of Benin, could improve the quality of the caregiver-patient/caregiver relationship of palliative patients. Indeed, according to Malaboeuf [35] , there are four levels of caregiver-patient relationship which are established in ascending order, namely:

The study also opens the way to future research focused on strengthening health literacy as a lever for autonomy and social justice at the end of the life course.

It should be noted that the study has a significant methodological limitation, that of the sample size (n = 25), but this does not affect the scientific quality of the results obtained. Indeed, this sample size reflects the operational characteristics of Palliative Care Units, which generally do not have many patients. It is therefore less linked to a methodological choice than to a structural and ethical constraint inherent to the reality of the palliative field. In the sampling process, not only patients hospitalized at the time of the survey were included, but also those followed on an outpatient basis, particularly for chemotherapy or morphine. This methodological choice is therefore part of an exploratory and contextualized logic aimed at covering the entire target population accessible to the USP of the CNHU-HKM in Cotonou, the framework of the study. Although this approach does not allow us to claim national representativeness, it constitutes a solid basis that has made it possible to produce localized quantitative data and shed light on a poorly documented issue, and offers a first structured empirical basis for identifying significant trends and laying the groundwork for future research on a larger scale.