Patients with both HIV and diabetes have an increased risk of albuminuria

Michael Carter
Published: 17 October 2011

HIV-positive individuals with diabetes have a significantly higher prevalence of albuminuria than patients living with either disease alone, US investigators report in PLoS One.

Over a third of patients with HIV and type-2 diabetes had albuminuria (albumin in urine), an important marker of kidney disease. Diabetes, higher HIV viral load and treatment with the antiretroviral drug abacavir (Ziagen, also in the combination pills Kivexa and Trizivir) all had a significant relationship with albuminuria.

Thanks to effective antiretroviral therapy, the prognosis of many HIV-positive patients has improved dramatically. However, kidney disease is an increasingly important cause of serious illness and death in these patients. The exact reasons are unclear, but may include traditional risk factors, the inflammatory effects of HIV, and treatment with some antiretroviral drugs.

The prevalence of type-2 diabetes, another risk factor for kidney disease, is also increasing in HIV-positive patients. Although it is well known that both HIV and diabetes can cause renal dysfunction, little is known about kidney disease in HIV-positive individuals living with diabetes.

Albuminuria is a recognised marker of kidney damage, which is also associated with an increased risk of cardiovascular disease. Research suggests that between 9% and 11% of HIV-positive patients have microalbuminuria (small levels of albumin in their urine), and the prevalence of microalbuminuria in individuals with type-2 diabetes is as high as 25%.

Given the association of both HIV and diabetes with microalbuminuria, investigators designed a cross-sectional study assessing the prevalence of albuminuria in a cohort of patients with HIV and type-2 diabetes, as compared to control populations of HIV-positive patients without diabetes, and diabetic patients without HIV.

The study included 73 patients with both HIV and diabetes, 82 individuals with HIV alone, and 61 HIV-negative patients with type-2 diabetes.

Patients with diabetes (with and without HIV) were older, had higher body mass index, and were more likely to be African American than the HIV-positive patients without diabetes.

Comparison of the patients with HIV showed that those with diabetes were more likely to be antiretroviral naïve (16% vs. 1%; p = 0.0006); less likely to be currently using HIV therapy (77% vs. 94%; p = 0.002); and less likely to have an undetectable viral load (56% vs. 81%; p = 0.0007), than patients without diabetes.

Albuminuria was defined as a urinary albumin/creatinine ratio above 30 mg/g. The condition was present in 34% of patients with HIV and diabetes, compared to 13% of those with HIV alone, and 16% of HIV-negative diabetic controls (p = 0.005).

After adjusting for factors known to increase the risk of kidney dysfunction such as age, race, and body mass index, the investigators found that infection with HIV (p = 0.02) and diabetes (p = 0.03) remained significantly associated with an increased risk of albuminuria.

“Though albuminuria is considered an important complication of both diabetes and HIV, our study is the first to report on the prevalence of albuminuria among individuals affected by both disease,” write the investigators. “We found that HIV and diabetes have additive effects in regards to early kidney dysfunction.”

Analysis was then restricted to patients with HIV. The investigators found that the urinary albumin/creatinine ratio had a significant correlation with viral load (p = 0.0005).

“Active HIV infection may contribute to a broad spectrum of kidney injury,” suggest the authors. “Alternatively, viremia may be marker of medication non-adherence which itself may play a role in albuminuria in individuals with HIV and diabetes.”

There was a higher prevalence of albuminuria among patients taking an antiretroviral regimen containing abacavir compared to individuals taking an alternative drug (37% vs. 19%; p = 0.03). Further analysis showed that patients with albuminuria had greater cumulative exposure to abacavir (30 vs. 11 months; p = 0.01).

The association between the increased risk of albuminuria and higher viral load and cumulative exposure to abacavir remained significant after results were adjusted to take into account potential confounders (p = 0.002 and p = 0.001 respectively).

Further adjustment was also made to take account of total years of antiretroviral therapy, but nevertheless both a diagnosis of diabetes (p = 0.003) and abacavir therapy (p = 0.002) remained significantly associated with albuminuria.

No other antiretroviral drug was associated with albuminuria.

“We found that the prevalence of albuminuria in individuals with HIV and diabetes was two fold greater than that of individuals with either disease alone,” conclude the investigators. They call for further studies “on the persistence, progression and management of albuminuria in this unique and at-risk population.”

Reference

Kim PS et al. Increased prevalence of albuminuria in HIV-infected adults with diabetes. Plos One 6(9): e24610, doi.10.1037/journal.pone.0024610, 2011 (click here for the open-access article).