[Urinary albumin excretion by patients with type 2 diabetes mellitus. Effect of blood pressure and metabolic regulation].
BACKGROUND
There is still controversy as to whether increased urinary albumin excretion (UAE) in patients with type 2 diabetes mellitus may have similar pathognomonic relevance as in type 1 diabetes and whether improved metabolic control may beneficially influence increased UAE in type 2 diabetic patients to the same extent as in type 1 diabetic patients.


METHODS
In a cross-sectional study in 234 patients with type 2 diabetes (age, 64 +/- 1 years, known duration of diabetes, 14 +/- 1 years) UAE, haemoglobin A1, blood pressure, cholesterol, triglyceride and creatinine levels were measured and signs of retinopathy were evaluated. Results were compared with the findings in 247 patients with type 1 diabetes (age, 39 +/- 1 years, duration of diabetes, 15 +/- 1 years). In a longitudinal study, UAE, haemoglobin A1, blood pressure, cholesterol, triglyceride and creatinine levels were measured in 41 patients with type 2 diabetes and secondary failure of oral hypoglycemic treatment (age, 62 +/- 1 years, known duration of diabetes, 11 +/- 1 years) before and after 2-year insulin treatment.


RESULTS
In the cross-sectional study, 39% of the type 2 diabetic patients had increased UAE, 27% had microalbuminuria, in contrast to 21% and 14%, respectively, of the type 1 diabetic patients (p < 0.01). In type 2 diabetes, macroalbuminuria was detected after an average of 15 +/- 2 years in contrast to 25 +/- 2 years in type 1 diabetes (p < 0.01). In comparison to macroalbuminuric type 1 diabetic patients, macroalbuminuric type 2 diabetes patients exhibited a lower prevalence of renal insufficiency (30 vs. 53%, p < 0.05) as well as of retinopathy (59 vs. 88%, p < 0.05), but a higher prevalence of hypertension (93 vs. 65%, p < 0.05) as well as of hyperlipidaemia (p < 0.01). There was a significant relation between UAE and haemoglobin A1 in patients with type 1 diabetes (p < 0.01) which could not be demonstrated in type 2 diabetic patients. In the longitudinal study, UAE fell from 86 +/- 28 to 51 +/- 16 mg/24 hours (p < 0.05) and the prevalence of UAE of more than 30 mg/24 hours decreased from 45 to 25% (p < 0.05) after 2-year insulin treatment, while blood pressure remained constant and haemoglobin A1 fell from 12.3 +/- 0.4 to 8.8 +/- 0.3% (p < 0.01). In comparison to patients with normal or normalized UAE after 2 years, patients with persistently elevated UAE had more advanced kidney disease (p < 0.05), more pronounced insulin resistance and a higher prevalence of calculated mean arterial blood pressure above 103 mm Hg and of haemoglobin A1 higher than 9% (normal, < 7%) in the course of the study (p < 0.05).


CONCLUSIONS
In patients with both type 2 and type 1 diabetes mellitus, increased UAE is a marker for the nephropathy-related sequelae of long-term hyperglycaemia. In type 2 diabetic patients, however, the frequently pre-existing hypertension as well as other disease mechanism of the "metabolic syndrome" ("syndrome X") may additionally determine course and progression of diabetic kidney disease.
Jungmann
E
E
Medizinische Klinik, Klinikum der Johann-Wolf-gang-Goethe-Universität Frankfurt am Main.
Carlberg
C
C
Schallmayer
M
M
Schumm-Draeger
P M
PM
D000368:Aged; D000419:Albuminuria / Q000188:drug therapy / Q000503:physiopathology*; D001786:Blood Glucose / Q000378:metabolism*; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology*; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy / Q000503:physiopathology*; D003928:Diabetic Nephropathies / Q000188:drug therapy / Q000503:physiopathology*; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use; D007328:Insulin / Q000627:therapeutic use; D007333:Insulin Resistance / Q000502:physiology; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged
D001786:Blood Glucose; D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D007328:Insulin
Albuminausscheidung im Urin bei Patienten mit Typ-2-Diabetes mellitus. Einfluss von Blutdruck- und Stoffwechseleinstellung.