Correlations between serum inflammatory markers and comorbidities in patients with end-stage renal disease

Chronic inflammatory processes are common in patients with renal disease, especially those with end-stage renal disease (ESRD), in whom inflammatory markers have been shown to increase with renal function deterioration. ESRD is usually accompanied by other chronic diseases such as hypertension and diabetes. The relationships between ESRD comorbidities and serum levels of inflammatory markers have not yet been fully understood. The aim of this study was to assess serum levels of inflammatory markers in different ESRD cohorts and to investigate the correlations between these inflammatory markers and disease comorbidities.

A total of 147 patients were grouped according to their comorbid conditions: diabetic only, hypertensive only, diabetic and hypertensive, and neither diabetic nor hypertensive. Serum levels of C-reactive protein (CRP), tumour necrosis factor-alpha (TNF-α), and interleukin-1-beta (IL-1β) were investigated in different ESRD cohorts by enzyme-linked immunosorbent assay.

Serum CRP and TNF-α levels were high in diabetic patients (p = 0.0001), hypertensive patients (p = 0.0001), and those who had both diseases (p = 0.0001), when compared to ESRD patients without these comorbidities. There was no significant change in serum IL-1β levels between patients with diabetes mellitus and/or hypertension compared to patients who did not have these diseases.

Our results showed that, in ESRD patients, CRP and TNF-α seem to be largely affected by patients' comorbidities, unlike IL-1β, which might be affected more by the dialysis process even in the absence of comorbidities.