**5. Conclusion**

Uremia occurs due to retention of a variety of substances with different properties. Historically, we have had one marker, urea, to describe the total uremic environment in dialysis patients. There is a need to follow a wider spectrum of uremic toxins that are more strongly linked to morbidity and survival than urea alone. Our ambition with this research, using combined optical methods, is to be able to monitor several important uremic toxins online in the future. Patients will benefit from more patientcentred, integrated and cost-efficient care, as feedback for clinicians helps to improve and personalize the treatment quality, minimizing costly adverse effects. Feedback to patients helps to integrate patients into their own treatment, increasing patients' compliance and well-being.
