The results indicated improvements in various aspects related to the students' knowledge of PH, both in their subjective perception (sense of learning from the sessions; sense of interconnection with the environment and the importance of its practical application) and when objectively measuring how many diseases they could relate to PH. The perception of the impact that environmental changes, such as climate change, have on patients' health; concern about climate change; and the importance for students in health professions of learning about PH did not show significant changes, possibly due to their high prior concern. The secondary analysis, which showed that students whose responses were in the first quartile experienced statistically significant gains in all items, supports this hypothesis. It indicates that those with the least awareness of the connections between environmental changes and health were able to significantly enhance this understanding through the educational intervention.
This aspect resembles the responses about these items from healthcare professionals in at least one other study that evaluated healthcare workers who voluntarily undertook a PH course. In that study, the vast majority believed that environmental changes, such as climate shifts, would affect their patients' health; slightly less than a third felt alarmed, and about two-thirds were concerned about climate change. Almost all believed that PH was an important or very important topic for health students to learn [7].
The qualitative data indicate that, in general, students recognized the relevance of these educational sessions because they addressed this very current and pertinent topic for life in society and expanded one's perspective when facing a patient. Some students displayed limited openness to what was being introduced for teaching, citing that environmental education was already imparted during their school years or seeing no connection with medicine. However, although environmental education and traditional sustainability approaches have been on the rise in both formal and informal educational settings in recent years, PH introduces distinct novel elements. PH emphasizes the connection to human health, addresses climate changes, and adopts a systemic viewpoint on the complexity of relationships, also integrating the issue of inequity.
The innovative methodology was appreciated by the majority of students, but the multitude of diverse methods in a brief period made it dense, and certain specific aspects faced criticism. A common request from both groups was for more in-depth exploration and additional time to understand the content. The provided references encompassed accessible materials such as quick videos, podcasts, and interactive websites, in addition to more comprehensive sources such as scientific articles. However, it appears that students did not have ample time to explore most of these options.
There was no significant difference in learning outcomes between Class 1 and Class 2, even though Class 2 demonstrated a significantly greater understanding of the relationship between cardiovascular diseases and depression with PH. This likely occurred because Class 2 was exposed to a lecture, which was a suggestion from Class 1. In turn, Class 2 proposed that this should be a recorded lesson to be viewed at home or should be delivered in person, allowing for more interaction and discussion. Even though the classes had slightly different instructional approaches, both were effective.
The close-ended question, "How interconnected do you feel with the environment?", although in some ways alluding to the unreal division between humanity and nature, showed a statistically significant increase after the intervention. This indicates that the "IWN" activities contributed to feelings of interconnection. However, we did not explore to what extent this reflects a commitment to environmental protection, as another study did with healthcare professionals. In that study, over half of the participants described themselves as connected to the environment, slightly less than half felt interconnected and committed to protection, very few were indifferent, and almost none were disinterested [7].
Concerning their personal lives, students indicated that the approach effectively stimulated more thoughtful reflections on their habits, with some considering more collective actions. One student expressed that such lessons can add to students' anxiety about environmental degradation, termed eco-anxiety, something that should be anticipated and addressed when discussing this topic. Some students conveyed feelings of helplessness; others felt a sense of urgency and a call to action to address these issues. However, in general, the educational intervention did not seem to significantly alter the level of concern about climate change, which was already high before the sessions.
Eco-anxiety is a reasonable and functional response and should be channeled to generate momentum, rather than paralysis or mental health pathologies [15]. It is essential to highlight positive experiences and emphasize that every action now, in any field of knowledge and potential intervention, matters, driving collective movement and fostering hope [16]. This should be done without losing our ability to appreciate beauty and to approach transformative tasks at a non-debilitating pace [17]. Perhaps one way to understand the Anthropocene is to treat it as an immense rite of passage, which, while painful and unfair, will result in mature adults accountable for their actions [18].
Regarding the impact on students' professional lives, the objective inquiry about the importance of physicians incorporating PH into their practice saw a significant increase before and after the intervention. Numerous comments were made about the broadened perspective on the health-disease process, which offers the potential to contemplate new protective guidelines against risk factors and co-benefits. This also includes reducing the environmental footprint of the healthcare system and making broader, scientifically-backed health recommendations in society. Compared to another study, when healthcare professionals were questioned about the applicability of PH in their field, many responded affirmatively, some believed its application was partial, and very few felt it was not applicable [7]. To truly assess the personal and professional impacts, this study has limited evaluative capacity, as a prolonged period of observation would be required to gauge the actual repercussions.
One teacher noted that the students did not see themselves as active protagonists for PH, suggesting the addition of a question to the portfolio: “In what actions could you, as a student, engage to promote the health of individuals, such as your interviewed patient?”. In subsequent sessions with a following class, there was also a suggestion that the students develop an intervention project based on the studied case. Regarding this research's assessment, we recognized that we could have evaluated whether the students felt encouraged to initiate change while still in their student roles. To our knowledge, one student mentioned considering the establishment of a University Planetary Health Club or League.
The curriculum is a battleground for knowledge and is contextualized in its time. Increasingly, there is an emerging need to introduce medical students to a perspective termed as "planetary health lenses" [19]. In 2022, a working group affiliated with the World Health Organization made a call to those involved in health education to ensure that graduates can identify, prevent, and respond to the impacts of climate change and environmental degradation on health [20]. This statement resonates with the stance of various national and international entities on the subject [6, 21, 22, 23]. Overall, the interventions were effective within the available class time; however, it became abundantly clear to the researcher that the topic of planetary health would be better understood if given more time for content assimilation, exploration, and debate on its nuances and complexities, reflection on the domain of “IWN”, and for students to become familiar with more examples of creating momentum and system change. This would allow them to see themselves as protagonists and envision creative possibilities for intervention [24].
Globally, there is advocacy for the transversal insertion of this content throughout the course [22, 25], and there is a pressing need to take on the challenge of coordinating such an implementation, possibly coupled with the need to train various professors on the subject. However, we believe it is crucial that in some subject - be it integrative, public health, clinical, or solely focused on planetary health - the topic is addressed comprehensively. This approach ensures that students grasp its full scope [26] and complexity [27], as was done in this activity.
This study contributes to the field of planetary health education, as it qualitatively and quantitatively assessed the first known Brazilian didactic materials on planetary health and elaborates on the challenges and nuances of teaching planetary health to medical students. As a result of the sessions, it is also worth noting that the course teachers began to adopt this planetary health module and included a question for all interviews/portfolios conducted in the course: "Relate aspects of the interviewed patient and the studied disease to Planetary Health."
The limitations of this study are that it was conducted at only one university and there isn't a validated objective questionnaire about learning in planetary health available in the scientific literature. However, this study adds to the literature by reflecting on the successes and challenges related to the utilized questionnaire, which will serve as a basis for the development of enhanced ones in the future. Future educational interventions on planetary health should consider allocating more time for teaching this subject to students, focusing on listening to and dialoguing more with students, exploring the domain of "movement building and system change" more thoroughly, and considering interviewing real patients in a Primary Health Care context, where the "minute for the planet" individual approach [28] and community approaches can be explored more closely to their territory. Future studies should also consider assessing how students perceive themselves as agents of change in their current role as students.