Chronic kidney disease in hypertension under specialist care: the I-DEMAND study

Italy Developing Education and awareness on MicroAlbuminuria in patients with hyperteNsive Disease is an observational, cross-sectional, multicenter study aimed at determining prevalence and correlates of chronic kidney disease (CKD) among Italian hypertensive patients attending out-patient referral clinics. CKD was defined as glomerular filtration rate (GFR) less than 60 ml/min per 1.73 m (Modification of Diet in Renal Disease equation) or urine albumin to creatinine ratio of at least 2.5 mg/mmol in men and of at least 3.5 mg/mmol in women or both.

Among 3534 study patients (mean age 61 years, 54% male patients, 37% diabetic patients), the prevalence of microalbuminuria, reduced GFR, and CKD was 27, 26, and 42%, respectively. Only 11% of patients had concomitant microalbuminuria and reduced GFR. Sex, smoking, systolic blood pressure, glucose, and GFR were the independent predictors of albumin to creatinine ratio, whereas sex, age, history of cardiovascular diseases, uric acid, abdominal obesity, and albumin to creatinine ratio were more closely related to GFR. The presence of CKD was associated with older age, smoking, higher systolic and pulse pressure levels, impaired fasting glucose, hyperuricemia, and previous cardiovascular disease. Furthermore, CKD was not only associated with a greater use of renin-angiotensin system-inhibiting, lipid-lowering and antiplatelet drugs but also with inadequate blood pressure control.

Renal abnormalities are found in a significant number of hypertensive patients. CKD occurs more often in older patients and in those with associated metabolic risk factors or clinical conditions. These results suggest the need to improve awareness of the role of renal damage as a component of global risk and to develop appropriate therapeutic strategies to reduce morbidity and mortality in this specific subgroup of patients.