Implications of Albuminuria on Kidney Disease Progression

Albuminuria is recognized in all hypertension guideline statements as a cardiovascular risk factor and indicator of kidney disease. Recent data also demonstrate a strong association between the presence of microalbuminuria and elevations in C-reactive protein. Thus, the increased membrane permeability that generates microalbuminuria may be secondary to an inflammatory process. Progression from microalbuminuria (>30 and < or =300 mg albumin/g creatinine) to macroalbuminuria (>300 mg albumin/g creatinine) indicates a worsening of vascular disease and the presence of kidney disease. Recent outcome trials of kidney disease progression have demonstrated the best results among those with reductions in albuminuria in concert with blood pressure (BP) reduction. Thus, use antihypertensive agents that not only lower BP but also lower or normalize albuminuria levels. All recent guideline statements support the use of agents that block the renin-angiotensin-aldosterone system as part of a regimen to achieve the BP goal. Further lowering of albuminuria may be achieved by adding either a nondihydropyridine calcium antagonist such as verapamil or diltiazem, or aldosterone receptor blockers. Use of an angiotensin receptor blocker added to an angiotensin-converting enzyme inhibitor or vice versa can further lower albuminuria by an additional 30%-40%, which is not true of the additional lowering of BP.