Abstract:
OBJECTIVE: Hypertensive patients with CKD present an increased risk for cardiovascular mortality. Among the proteins synthesized and released from adipose tissue, resistin is a cytokine whose physiologic role has been the subject of much research and controversy. We and others have demonstrated that serum resistin levels are higher in patients with CKD and correlate directly with inflammatory markers, including TNF-α and hsCRP. Since inflammation has been consistently linked to atherosclerosis, death, and cardiovascular (CV) events, our goal was to investigate the interaction between resistin levels and long term all-cause and CV mortality in elderly non-obese and non-diabetic with hypertension.
DESIGN AND METHOD: We studied 80 patients (52 men/28 women) 70.9 ± 8.6 years of age with hypertension and CKD. Exclusion criteria was obesity and diabetes mellitus, active infection, acute illness, chronic inflammatory disease or cancer, and immunosuppresive, anti-inflammatory or anti-lipidemic drugs. Demographic data, clinical information and blood samples were collected prospectively. The patients were observed for 5 years.
RESULTS: During the follow-up 28 of 80 (35%) patients died: 16 (57%) deaths due to CV events and 12 (43%) of other causes. Patients who died were older and had higher DBP, compared to survivors, but had no differences in BMI, smoking, SBP and HR. Deceased patients had higher WBC, hsCRP, BUN, creatinine, cystatin C, phosphate, magnesium and potassium levels and lower eGFR, Hct/Hg, T3, T4, total cholesterol, LDL-C, albumin and sodium levels compared to survivors. No significant differences in platelet count, TNF-α, fibrinogen, oxLDL, ADMA, HgA1C and HOMA-index were revealed between the groups. eceased patients had significantly higher resistin levels than survivors at baseline (p = 0.025), but adiponectin, visfatin and leptin did not differ between the two groups. Five variables, namely resistin, sodium, cholesterol, T3 and WBC remained significantly associated with survival and were used in the multivariate Cox regression analysis, which revealed that only resisitin, cholesterol and WBC maintained their discriminatory ability, as independent predictors of mortality both by forward and backward stepwise analysis.
CONCLUSIONS: Elevated serum resistin was a significant independent biomarker of CV and all-cause mortality in elderly, non-diabetic CKD patients with hypertension.