I get greener (with a little help from my patients). Patients as key drivers of greener peritoneal dialysis

Chronic kidney disease represents a growing global epidemic, affecting approximately 10% of the world's population, and is projected to become the fifth leading cause of years of life lost by 2040.1 There are currently about 3.8 million patients receiving dialysis worldwide, of whom approximately 89% are treated with hemodialysis (HD) and 11% with peritoneal dialysis (PD).2,3 Although HD is one of the most resource-intensive medical procedures due to its high consumption of energy and water, PD also accounts for a significant proportion of the carbon footprint of medical treatments.4 It has been reported that PD generates approximately 2000 to 3300 kg of carbon dioxide equivalents (CO2e) per patient per year depending on the modality—­automated or continuous ambulatory PD—whereas HD produces about 4800 kg of CO2e per patient per year.5,6 These figures may be lower when incremental dialysis is employed. Most of the ­environmental impact of PD arises from the production and ­disposal of plastic bags and PD solutions, as well as from the transportation of PD materials to patients' homes or of patients to hospitals for monthly consultations.5,6 Recycling programs for polyvinyl chloride (PVC) PD solution bags have been proposed as an option to reduce the carbon footprint of treatment and decrease waste generation.7 However, at present, such virtuous initiatives remain exceptions and require dedicated infrastructure, logistical organization, and patient collaboration. In this issue of the Journal, Trigo and colleagues report the results of a survey conducted among PD patients from two Portuguese centers regarding their recycling habits related to PD materials, and their opinions on other initiatives that may help to reduce the environmental impact of PD.8 The authors enrolled 90 patients, the vast majority of whom (84.4%) reported recycling at least one type of PD-related material. Most patients who engaged in recycling reported recycling cardboard and paper items (83.3%) and approximately two-thirds recycled plastic PD materials. A significant proportion (21.3%) reported recycling PD solution and drainage bags despite recommendations to the contrary; these materials are considered hazardous waste and unrecyclable in Portugal. Recycling habits were not associated with patient age, place of residence, or PD modality, but were mainly related to pre-existing recycling behaviors. Indeed, all patients who reported not being accustomed to household recycling also stated that they did not recycle PD materials. In addition, most patients expressed a preference for in-person consultations rather than telemedicine and reported satisfaction with the current frequency of home delivery of PD supplies, rejecting alternative delivery options that may reduce delivery-related emissions, including the possibility of collecting materials from centralized hubs. This manuscript highlights an important issue and provides food for thought. The transition toward greener PD cannot overlook the contribution of patients. Whilst it has been suggested that bioplastics could be used in the production of PD bags to incorporate circular economy principles and limit waste generation from PD, this would require substantial investment and commitment from manufacturers, as well as serious consideration of the ethical and agricultural implications of diverting land used for food production to instead producing materials for packaging.9 It is unlikely the current landscape of PD packaging will significantly change in the near future. For the time being, therefore, efforts to reduce the environmental impact of PD should leverage the third of the well-known principles for mitigating climate change: the “three Rs”—Reduce, Reuse, and Recycle. Recycling paper and cardboard represents the most easily actionable first step, as most individuals are already accustomed to doing so and dedicated collection systems and pathways are widely available. People are also familiar with plastic recycling, as collection of household plastic waste (for example, polyethylene terephthalate [PET] water bottles) for delivery to recycling facilities is commonplace. However, recycling of all types of plastic is not universally available. When it comes to PD bags, the situation is more complex as they are composed of different types of plastics. Indeed, in the Mexican experience, the PVC components needed to be manually separated from polypropylene components prior to delivery to the recycling facility.7 Whilst PVC is fully recyclable, as described earlier this is not widely available. Furthermore, some jurisdictions unfortunately consider PD solution and drain bags hazardous hospital waste, further limiting access to recycling (Table 1). This was the case for the PD patients in Portugal described in the study by Trigo and colleagues. This highlights the importance and difficulty of providing patient education about waste management specific to the geographic location and PD products used locally to not only improve rates of recycling but to also avoid inadvertent contamination of recycling streams. Unfortunately, Trigo and colleagues do not specify the likely outcome of the PVC PD solution and drain bags their patients mistakenly directed to recycling. Different peritoneal dialysis bag waste regulations across the world. Household waste Household waste for the most part Clinical waste collected by municipal/NHS services Often treated as healthcare waste returned to dialysis centers Often treated as healthcare waste, returned to dialysis centers Mixed practice Mixed practice Often biomedical waste under medical-waste rules Household waste after draining Usually considered hazardous biomedical waste Household waste after draining Often medical waste collection via dialysis programs Abbreviations: NHS, National Health System; PD, peritoneal dialysis; UAE, United Arab Emirates. It is also noteworthy that most patients expressed a preference for in-person consultations. This has important environmental implications, as each trip to the hospital is typically associated with greenhouse gas emissions unless it is undertaken on foot, by bicycle, or using electric vehicles powered by renewable energy. Since many patients have comorbidities that limit long-distance walking or cycling, or live far from the hospital, cars remain the most commonly used means of transportation. According to this study, telemedicine—although potentially associated with a lower carbon footprint—may still be perceived as inferior to in-person consultations by patients, particularly older individuals and in healthcare systems where telemedicine services are not yet sufficiently developed. Similarly, most patients were unwilling to modify the current system for PD supply procurement or the frequency of home deliveries. Although the benefits of centralized distribution hubs where patients collect their own PD supplies have yet to be clearly demonstrated, this raises questions about the level of importance that patients assign to the environmental impact of their treatments. While concerns about climate change should not be the sole driver of changes in medical practice at the expense of maintaining the highest standards of care, education represents a key strategy to inform patients about sustainable alternatives that are not clinically inferior.4 Education requires time and commitment, but the findings of this survey suggest that younger patients may be more receptive to receiving information and new data through digital channels. Starting with individuals of the younger generations—who are often more sensitive to environmental issues—may therefore represent an effective approach. Indeed, long-standing habits and inertia are among the main barriers to change. Future surveys building on the work of Trigo and colleagues exploring patient perspectives on barriers to the implementation of green initiatives in PD are crucial to increase the likelihood of successful outcomes. In summary, patient collaboration is essential for a smoother transition toward greener nephrology. Patients are among our most valuable allies while we await broader engagement from policymakers and industry to support and sustain this transition. Paraphrasing the Fab Four, we may become greener “with a little help from our patients”. MT: conceptualization; MT and JW: writing original draft, review and editing. None declared.