Objective: The aim of this study was to describe the effect of intensified antihypertensive therapy based on a structured teaching and treatment programme on the prognosis of hypertensive type 1 (insulin-dependent) diabetic patients with kidney disease.
Design: The study was a controlled, prospective, parallel, 10-year follow-up trial.
Patients and interventions: A sequential sample of 91 hypertensive type 1 diabetic patients with overt diabetic nephropathy was prospectively followed for 10 years. Forty-five patients (intensified antihypertensive therapy; IT group) participated in an intensified antihypertensive therapy programme and 46 patients received routine antihypertensive treatment as provided by family physicians, consultants and local hospitals (routine antihypertensive therapy; RT group).
Outcome measures: The main endpoint was death; secondary endpoints were renal replacement therapy, blindness and amputation.
Results: Blood pressure was reduced in the IT group and increased in the RT group. During the follow-up period, 29 patients died, seven in the IT group and 22 in the RT group. The survival curves were significantly different (P = 0.0008). The main causes of death were cardiac. In a multiple Cox proportional hazards model, allocation to the IT group reduced the mortality risk [relative risk (RR) = 0.213; 95% confidence interval 0.089–0.509, P = 0.0005], while age (P = 0.0039) and mean blood pressure (P = 0.0113) increased this risk. In multiple Cox or multiple logistic regression models, the risks of dialysis (RR = 0.269, 95% confidence interval 0.110–0.656, P = 0.0039), blindness (odds ratio = 0.158, 95% confidence interval 0.037–0.684, P = 0.0136), and amputation (RR = 0.181, 95% confidence interval 0.047–0.703, P = 0.0135) were significantly lower in the IT group compared with the RT group (log rank P = 0.0008).
Conclusion: We conclude that intensified antihypertensive treatment, based on a hypertension teaching and treatment programme, reduces long-term morbidity and mortality in patients with diabetic nephropathy.
1Department of Metabolic Diseases and Nutrition (WHO-Collaborating Centre for Diabetes), Heinrich-Heine-University of Düsseldorf, Germany.
2Correspondence and requests for reprints to Peter T. Sawicki, Department of Metabolic Diseases and Nutrition, Heinrich-Heine-University of Düsseldorf, PO Box 101007, D-40001 Düsseldorf, Germany. Tel: +49 211 81 17836; fax: +49 211 81 18772 e-mail: firstname.lastname@example.org
Received 28 October 1998 Revised 22 June 1999 Accepted 23 June 1999