Renal resistive index and parathyroid hormone relationship with renal function in nondiabetic patients.
BACKGROUND
The renal resistive index (RRI) reflects intrarenal vascular resistance and stiffness, which are associated with chronic kidney disease. The links connecting renal function, intrarenal arterial resistance, and parathyroid hormone (PTH) with hypertension and metabolic factors remain elusive. The aim of this study is to investigate the possible relationship of RRI with glomerular filtration rate, PTH, hypertension, obesity (body mass index and waist-to-hip ratio), bioelectrical impedance analysis in body composition assessment, serum lipids, and insulin resistance assessed by homoeostasis model insulin resistance index.


METHODS
This study was carried out on 387 (246 women, 141 men) nondiabetic patients, between >25 and <75 years, referred to an Internal Medicine Clinic and Day Hospital for essential hypertension, overweightness-obesity, and/or dyslipidemia. Lower salt/lower calorie Mediterranean diet, physical activity increase, smoking withdrawal, and lifestyle counseling, provided by a health psychologist support, were prescribed.


RESULTS
Higher hypertension risk, present in 42.5% of the overall group of eligible patients (164/387), is associated with high PTH and high RRI, along with greater renal insufficiency, insulin resistance, and obesity. There is a straight linear relationship of RRI to PTH (0.202; p=0.009) in arterial hypertension, which is not observed in normal blood pressure patients. By gender-adjusted multiple linear regression analysis, it was found that fat mass, waist-to-hip ratio, and PTH account significantly for 62.3% of the variance to RRI in hypertensive patients.


CONCLUSIONS
Increased arterial stiffness and intrarenal arterial resistance are associated with higher PTH in arterial hypertension; obesity (defined by greater fat mass and waist-to-hip ratio) and PTH are the independent conditions that account significantly for higher RRI.
Dipartimento di Medicina Interna, Istituto di Medicina Interna e Terapia Medica, Facoltà di Medicina e Chirurgia, Università di Catania, Catania, Italy. guglielmotrovato@unict.it
Guglielmo M
GM
Trovato
Giuseppe Fabio
GF
Martines
Francesca M
FM
Trovato
Clara
C
Pirri
Patrizia
P
Pace
Daniela
D
Catalano
D000328:Adult; D000368:Aged; D015992:Body Mass Index; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D006973:Hypertension / Q000150:complications; D007333:Insulin Resistance; D007668:Kidney / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications* / Q000503:physiopathology; D010281:Parathyroid Hormone / Q000097:blood*; D051436:Renal Insufficiency, Chronic / Q000209:etiology*; D014463:Ultrasonography; D014655:Vascular Resistance / Q000502:physiology*; D059289:Vascular Stiffness / Q000502:physiology*; D049629:Waist-Hip Ratio
D010281:Parathyroid Hormone