Voxel-based morphometry has been used in the study of alterations in brain structure in type 1 diabetes mellitus patients. These changes are associated with clinical indices. The age at onset, pathogenesis, and treatment of type 1 diabetes mellitus are different from those for type 2 diabetes mellitus. Thus, type 1 and type 2 diabetes mellitus may have different impacts on brain structure. Only a few studies of the alterations in brain structure in type 2 diabetes mellitus patients using voxel-based morphometry have been conducted, with inconsistent results. We detected subtle changes in the brain structure of 23 cases of type 2 diabetes mellitus, and demonstrated that there was no signiifcant difference between the total volume of gray and white matter of the brain of type 2 diabetes mellitus patients and that in controls. Regional atrophy of gray matter mainly occurred in the right temporal and left occipital cortex, while regional atrophy of white matter involved the right temporal lobe and the right cerebellar hemisphere. The ankle-brachial index in patients with type 2 diabetes mellitus strongly correlated with the volume of brain regions in the default mode network. The ankle-brachial index, followed by the level of glycosylated hemoglobin, most strongly correlated with the volume of gray matter in the right temporal lobe. These data suggest that voxel-based morphometry could detect small structural changes in patients with type 2 diabetes mellitus. Early macrovascular atherosclerosis may play a crucial role in subtle brain atro-phy in type 2 diabetes mellitus patients, with chronic hyperglycemia playing a lesser role.

Purpose　To review evidence-based management of nephropathy in patients with type 2 diabetes.Data sources　A literature search (MEDLINE 1966 to 2000) was performed using the key word “diabetic nephropathy". Relevant book chapters were also reviewed.Study selection　Well-controlled, prospective landmark studies and expert review articles on diabetic nephropathy were selected.Data extraction　Data and conclusions from the selected articles that provide solid evidence to the optimal management of diabetic nephropathy were extracted and interpreted in light of our clinical research experience with many thousands of Hong Kong Chinese patients.Results　Hypertension, long diabetes duration, poor glycaemic control and central obesity are the most important risk factors. Microalbuminuria is a practical marker to predict overt nephropathy in type 2 diabetic patients. Risk factor modification, renal function monitoring and combined therapies are the current integrated approaches to manage patients with diabetic kidney disease. Optimal glycaemic control is the mainstay of treatment but effective antihypertensive therapy is also key to delaying the progression of diabetic nephropathy. Angiotensin-converting enzyme inhibitors and angiotensin Ⅱ receptor antagonists have important renoprotective actions independent of their blood pressure lowering actions. Conclusions　Diabetic nephropathy is the leading cause of end-stage renal disease worldwide. Monitoring renal function and screening for microalbuminuria will allow the identification of patients with nephropathy at a very early stage for intervention. Tight glycaemic control and aggressive antihypertensive treatment as well as the use of renin-angiotensin system inhibitors should substantially delay the progression of nephropathy.