Renal Impairment In Elderly Patients - Brief Article

Nutrition Research Newsletter, August, 2001 by P.A. Ellis, H.S. Cairns

Late referral of renal disease to the nephrologist is associated with increased morbidity and morality, and decreased psychological and social well-being of the patients once commenced on renal replacement therapy. One cause of late referral is a result of missed opportunities for screening in high-risk groups or overlooked biochemical results. Recent audit data suggest that existing guidelines on screening for renal disease in hypertensive and diabetic populations are frequently not followed, and when they are, action is not always taken. The present study provides some data as to the likely prevalence of renal impairment among a population of individuals at high risk of renal disease. A two-phase cross-sectional and screening study was performed to ascertain the prevalence of, and feasibility for screening for, renal impairment among individuals at high risk of renal disease in two General Practices in Southeast London.

The electronic databases of the practices were reviewed to identify all patients between 50 and 75 years of age known to have hypertension or diabetes. These patients were considered to be at high risk of developing renal disease, while being young enough to be referred and accepted for nephrological care and, where necessary, renal replacement therapy. Results of the most recent serum creatinine test and urine strip test for proteinuria were collected from the database. All patients without a serum creatinine result recorded in the last year were identified, and were invited by a letter to attend for screening. Clean-catch urine samples were strip-tested for the presence of protein and glucose.

The initial interrogation of the databases revealed 997 individuals between the ages of 50 and 75 years with a history of either diabetes, hypertension, or both, out of a total population this age of 5113. There were 632 available creatinine results, and invitations to be screened were sent out to 365 individuals. In total, 189 individuals attended for screening (52.5% of the hypertensives, 33.3% of the diabetics, and 71.4% of the individuals with both diseases that had been invited). The mean age of the cohort was 63.6 years, and 53% were female. Aggregate data on serum creatinines estimates, the prevalence of renal impairment in the hypertensives, diabetic, and both disease populations at 6.1%, 12.6% and 16.9%, respectively. Proteinuria was most common in those patients with diabetes, and least common in those with hypertension. Proteinuria was present in 7.9% of the hypertensives, 29.2% of the diabetics, and 20% of the individuals with both diseases.

The present study has demonstrated the relatively high prevalence of early renal disease in a high-risk population, and the relative ease and acceptability of screening. Early detection and treatment of some renal diseases (especially those associated with diabetes and hypertension) may permit the retardation, or even prevention, of the progression of renal disease. Therefore, early identification of these diseases may have important quality of life implications.

P.A. Ellis, H.S. Cairns. Renal impairment in elderly patients with hypertension and diabetes. Q J Med 94:261-265 (June 2001) [Correspondence: P.A. Ellis, Renal Administration, King's College Hospital (Dulwich), East Dulwich Grove, London SE22 8PT].