2.1. Patients and settings

Thirteen chronic HD patients (eight males and five females) undergoing dialysis at a hospital ward in Denmark were included in the study. Patients who were unstable (medically or psychologically), pregnant women or patients with a hemoglobin level lower than 6 mmol/L were not considered suitable for inclusion. Additionally, patients with unstable vascular access and those who were not stable on dialysis for at least 3 months were excluded. One of the participants was excluded due to technical issues, leaving 12 HD patients in the study. All the study subjects were Caucasian, and their median age was 70.5 (57–89) years. Eight of the patients were dialyzed using an arteriovenous fistula, and four patients used a catheter for vascular access. The patients had undergone maintenance HD for a median of 48 (6–144) months before the study began. The demographic characteristics are summarized in Table 1.

Demographic characteristics (n = 12).

Abbreviations: HD, hemodialysis, SD, standard deviation.