• Renal Disease
• Hypertensive Disease
• Diabetes Mellitus
• Diabetes & Kidney Disease
• Diabetes & Endocrinology Clinical Trials

The current worldwide prevalence of diabetes is estimated to be 366 million. One-third of these cases progress to nephropathy, a major cause of cardiovascular disease (CVD) and end-stage renal disease (ESRD). Progression through stages of nephropathy has not been well described in a large, well-characterized, population-based study. Suma Vupputuri, PhD, The Center for Health Research, Kaiser Permanente Georgia, Atlanta, Georgia, USA, described the prevalence, incidence, and progression of nephropathy and identified demographic and clinical characteristics that are associated with progression in a US population-based sample.

A total of 11,562 members of a managed care organization (Kaiser Permanente), aged 18 years and older, with hypertension and type 2 diabetes, a urine-to-albumin creatinine ratio (UACR) measurement during 2001–2003, and at least one follow-up UACR, were independently assessed for different stages of nephropathy. Three baseline stages of nephropathy were defined: normal albumin (<30 μm/mg), microalbuminuria (30–299 μm/mg), and macroalbuminuria (≥300 μm/mg). Records through 2008 were searched for individuals who showed progression from baseline to a higher stage of nephropathy, including ESRD. Progression was defined as the first UACR value that was recorded in a stage that was higher than baseline. Incidence was calculated as the number of new cases over the sum of the person-time of the at-risk population. Independent predictors of time to progression were assessed using Cox regression.

At baseline, 59% of subjects had normal albumin (n=6853), 30% had microalbuminuria (n=3492), and 11% had macroalbuminuria (n=1217). The incidence of nephropathy progression (per 1000 person-years) was 94.6, 44.1, and 6.7 for normal albumin, microalbuminuria, and macroalbuminuria, respectively. Table 1 shows the number of patients who progressed to higher stages of nephropathy.

Predictors of progression of nephropathy included age (per 5 years), race (Caucasian), diabetes duration (per year), systolic and diastolic blood pressure (per 5 mm Hg), HbA1C (per 1%), body mass index (per 5 kg/m²), estimated glomerular filtration rate (per 10 mL/min/1.73m²), use of ACE inhibitors/ARBs, CVD, and active heart failure.

Although the ability to extend the results of this study to a broader population may be limited by the study sample (ie, only patients with diabetes and hypertension who had health insurance were included), Dr. Vupputuri concluded that in one of the first studies to examine the progression of nephropathy in a US population-based sample of adults with diabetes and hypertension, the lifetime risk of nephropathy and its progression may be greater than previously reported. Developing strategies to slow and/or prevent the progression of nephropathy may reduce the burden of disease.

• © 2010 MD Conference Express