Diabetic nephropathy risk factors

Contrast-induced nephropathy has been defined as an increase in serum creatinine of at least 25% or an absolute increase in serum creatinine of at least 0.5 mg/dL within 48 to 72 hours of iodinated contrast administration and is associated with significant morbidity and mortality (75). Important risk factors include diabetes mellitus, chronic renal insufficiency, administration of large volumes of high osmolar contrast agents, and intravascular volume depletion. Numerous pharmacologic preventive measures have been studied, but consistent benefits have not been demonstrated. In a recent large retrospective study, preprocedural statin therapy was independently associated with a lower risk of contrast nephropathy and nephropathy requiring dialysis (76). 

Shcherbak NS, Shutskaya ZV, Sheidina AM, Larionova VI, Schwartz El. 1999. Methylenetetrahy-drofolate reductase gene polymorphism as a risk factor for diabetic nephropathy in IDDM patients. Mol Genet Metab 68 375-378. 

T. Koschinsky, C. J. He, T. Mitsuhashi, R. Bucala, C. Liu, C. Buenting, K. Heitmann, and H. Vlassara, Orally absorbed reactive glycation products (glycotoxins) an environmental risk factor in diabetic nephropathy, Proc. Natl. Acad. Sci. USA, 1997, 94, 6474-6479. 

The overall risk of developing diabetic nephropathy varies between about 10% of people with type 2 diabetes (diabetes of late onset) to about 30% of people with type 1 diabetes (diabetes of early onset). There are many factors, some known and others not, that affect the individual risk of developing diabetic nephropathy. Some of the factors that are known to increase the likelihood of getting diabetic nephropathy include ... 

Life expectancy is reduced by 5-10 years in Type-II diabetes compared with the non-diabetic population. The mortality risk, however, is not related to the duration of the disease (Nathan et al., 1986) but to the additional presence of other risk factors. In patients over the age of 75 at the time of diagnosis, mortality from diabetes is similar to that of age-matched non-diabetics. Coronary heart disease is the main cause of death in 58% of all Type-II diabetics (WHO, 1985b), followed by cerebrovascular accidents in 12%. Nephropathy is the cause of death in only 3%. 

Ravid M, Brosh D, Ravid Safran D, Levy Z, Rachmani R. Main risk factors for nephropathy in type 2 diabetes mellitus are plasma cholesterol levels, mean blood pressure, and hyperglycemia. Ann Intern Med 1998 158 998-1004. 

Although not a quantitative measure of renal function, urinary microalbuminuria has been identified as an early marker of renal disease in patients with diabetic nephropathy and numerous other conditions, such as hypertension and obesity. Patients with microalbuminuria (30 to 300 mg/day) on at least two occasions or overt albuminuria (>300 mg/day) should begin to receive pharmacotherapy. For children, microalbuminuria is considered present if albumin excretion exceeds 0.36 mg/kg per day, and overt albuminuria has been defined as an excretion rate that exceeds 4 mg/kg per day. The urinary albumin creatinine ratio is also an accurate predictor of 24-hour proteinuria, a marker of renal disease. Guidelines for monitoring indicate that a urine albumin creatinine ratio of >30 mg/g places the patient at increased risk of developing diabetic nephropathy and is an indication for the initiation of pharmacotherapeutic intervention. Microalbuminuria has also been suggested as a risk factor for renal dysfunction among patients with essential hypertension. ... 

Nephrotoxicity induced by radiographic contrast media is the third leading cause of hospital-acquired acute renal failure.The incidence rises from <2% in patients with low risk to 40% to 50% in high-risk patients such as those with pre-existent renal insufficiency or diabetes melhtus. " " The risk of contrast nephropathy increases as the number of risk factors increases, and diabetic patients with renal insufficiency have the greatest risk." " ... 

Ehe-existent kidney disease, particularly diabetic nephropathy with renal insufficiency, is the major risk factor. Conditions associated with decreased renal blood flow, including congestive heart failure and dehydration, also confer risk. The presence of multiple myeloma has been considered a relative contraindication for contrast use, but the risk appears to be associated with concomitant dehydration, renal insufficiency, or hypercalcemia rather than the diagnosis itself. Both... 

Goals of therapy in diabetes mellitus are directed at reducing symptoms of hyperglycemia, reducing the onset and progression of retinopathy, nephropathy, and neuropathy complications, intensive therapy for associated cardiovascular risk factors, and improving quality and quantity of life. 

In recent years microalbuminuria has received considerable attention due to the fact that it is a risk factor for the development of diabetic nephropathy and increased cardiovascular mortality in insulin-dependent diabetes mellitus (IDDM), and cardiovascular death in hypertension and noninsulin-dependent diabetes mellitus (NIDDM). 

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