Predictors of mortality in insulin dependent diabetes: 10 year observational follow up study

• Published in: BMJ 1996-09, Vol.313 (7060), p.779-784
• Main Authors: Rossing, Peter, Hougaard, Philip, Borch-Johnsen, Knut, Parving, Hans-Henrik
• Format: Article
• Language: English
• Subjects: Adult; Age of Onset; Aged; Albumins; Albuminuria - mortality; Cardiovascular Diseases - mortality; Cause of Death; Denmark; Denmark - epidemiology; Diabetes; Diabetes complications; Diabetes Mellitus, Type 1 - mortality; Diabetic nephropathies; Diabetic Nephropathies - mortality; Excretion; Female; Follow-Up Studies; Followup studies; Health risk assessment; Humans; Hypertension; Insulin; Insulin dependent diabetics; Male; Medical research; Middle Aged; Mortality; Predictors; Prognosis; Risk Factors; Survival Analysis; Survival Rate; Type 1 diabetes mellitus; Type 2 diabetes mellitus
• ISSN: 0959-8138; 0959-8146; 0959-535X; 1468-5833; 1756-1833
• DOI: 10.1136/bmj.313.7060.779

AbstractObjective: To evaluate the prognostic significance of microalbuminuria and overt diabetic nephropathy and other putative risk factors for cardiovascular and all cause mortality in insulin dependent diabetes.Design: Ten year observational follow up study.Setting: Outpatient diabetic clinic in a tertiary referral centre.Subjects: All 939 adults with insulin dependent diabetes (duration of diabetes five years or more) attending the clinic in 1984; 593 had normal urinary albumin excretion (/=300 mg/24 h).Main outcome measure: All cause and cardiovascular mortality.Results: Fifteen per cent of patients (90/593) with normoalbuminuria, 25% (45/181) with microalbuminuria, and 44% (72/165) with overt nephropathy at baseline died during follow up. Cox multiple regression analysis identified the following significant predictors of all cause mortality: male sex (relative risk 2.03; 95% confidence interval 1.37 to 3.02), age (1.07; 1.06 to 1.08), height (0.96; 0.94 to 0.98), smoking (1.51; 1.09 to 2.08), social class V versus social class IV (1.70; 1.25 to 2.31), log10 urinary albumin excretion (1.45; 1.18 to 1.77), hypertension (1.63; 1.18 to 2.25), log10 serum creatinine concentration (8.96; 3.34 to 24.08), and haemoglobin A1c concentration (1.11; 1.03 to 1.20). Age, smoking, microalbuminuria, overt nephropathy, and hypertension were significant predictors of cardiovascular mortality. Mortality in patients with microalbuminuria was only slightly increased compared with that in patients with normoalbuminuria. Median survival time after the onset of overt diabetic nephropathy was 13.9 years (95% confidence interval 11.8 to 17.2 years).Conclusions: Abnormally increased urinary albumin excretion and other potentially modifiable risk factors such as hypertension, smoking, poor glycaemic control, and social class predict increased mortality in insulin dependent diabetes. Microalbuminuria by itself confers only a small increase in mortality. The prognosis of patients with overt diabetic nephropathy has improved, probably owing to effective antihypertensive treatment.Key messagesMicroalbuminuria predicts increased mortality due to progression to overt nephropathyMicroalbuminuria by itself confers only a small increase in mortality after age 50The prognosis in patients with insulin dependent diabetes complicated by nephropathy has improved, probably owing to treatment with an