This study demonstrates older age and female sex to be independent predictors of impaired renal function in HIV-1 infected patients commencing HAART in Nigeria. This finding is at variance with that reported by the Development of Antiretroviral Therapy (DART) Trial group;14
they reported a younger age, male sex and a lower systolic blood pressure (BP) to be predictors of reduced renal function at initiation of ART in their cohort. This difference could be as a result of the differences in characteristics between the study populations, as the DART trial recruited over 3000 participants from three centers in two East African countries. The DART trial patients also had more severe immune deficiency than our patients (mean CD4 cells of 86 cells/mm3
and 146 cells/mm3
, respectively), though the age and sex distribution of both study populations were similar (37 years in DART as against 38.8 years in our cohort; 65% of DART patients were females and 60% were females in our cohort). Renal function is known to decline with age. Hence, this finding is consistent with what is expected and reported widely. However, unlike in other similar studies, we did not find an association between CD4 counts, viral load, HCV infection and reduced eGFR.1,6,13
This difference could be explained in part by the difference in study design, as one of these studies used MDRD equation to estimate the eGFR. Also, the patients in that study were already on HAART.13
These studies and others have shown that CD4 counts of <200 cells/μL were predictive of impaired renal function and that HIV patients with this severe immune deficiency were more likely to develop CKD, particularly if the viral load was >100,000 copies/mL and were not on HAART.14
This study also showed that 23.8% of the patients had reduced renal function. This is higher than what was reported by the DART trial group.15
They reported that 7% of their participants had mild reduction of eGFR (<60 mL/min) at initiation of HAART. This may suggest that our patients had more severe renal impairment at the time of initiation of HAART. However, in a recent study from this center, Chukwuonye et al
. reported that 50% of HIV-infected patients had mild reduction in eGFR.16
This is higher than what we have reported, although the fact that they used creatinine clearance to estimate the GFR could be a contributory factor. Other studies in Kenya and Uganda have also reported a mild reduction in eGFR of patients at initiation of HAART.17,18
It is important that HIV-infected patients with impaired renal function be identified before initiation of therapy as the eGFR will determine the dosing of their antiretroviral medications. Also, early initiation of ART should be instituted for these patients in line with the new WHO guidelines for initiation of ART.
There is a need for further studies to investigate renal function in HIV-infected individuals, the impact of ART on renal disease as well as to evaluate how well creatinine-based equations estimate renal function in HIV-1 infected individuals in Africa.
This study is limited by the fact that only a single measurement of serum creatinine was done, hence spurious results were not excluded. Also, the fact that the study is a retrospective study is another limitation. In addition, there was no assessment for proteinuria; however, this was the standard of care in the center as at the time of this study.
We therefore conclude that older age and female sex are independently associated with a higher likelihood of having lower GFRs at initiation of HAART among our study population. This study highlights the need for an increased awareness of CKD in HIV-positive individuals among clinicians in order to identify those patients at risk for renal disease and implement potentially preventative and therapeutic strategies.