Renal function in a cohort of HIV-infected patients initiating antiretroviral therapy in an outpatient setting in Ethiopia

Aim To evaluate the prevalence and associated factors of abnormal renal function among Ethiopian HIV-infected patients at baseline prior to initiation of antiretroviral therapy (ART) and during follow-up. Methods We conducted a retrospective observational cohort study of HIV infected patients who initiated ART at the outpatient ART clinic of Mehal Meda Hospital of North Shewa, Ethiopia from January 2012 to August 2018. Demographic and clinical data were abstracted from the medical records of patients. Renal function was assessed by estimated glomerular filtration rate (eGFR) calculated using the Modification of Diet in Renal Disease (MDRD) equation. Univariate and multivariate analysis were conducted to determine the factors associated with abnormal renal function at baseline and during follow-up. Results Among 353 patients, 70 (19.8%) had baseline eGFR <60 ml/min/1.73m2 and 102 (28.9%) had eGFR = 60–89.9 ml/min/1.73m2. Factors associated with baseline renal impairment (eGFR <60 ml/min/1.73m2) included female sex (AOR = 3.52, CI 1.75–7.09), CD4 count < 200 cells/mm3 (AOR = 2.75, CI 1.40–5.42), BMI < 25 Kg/m2 (AOR = 3.04, CI 1.15–8.92), low hemoglobin (AOR = 2.19, CI 1.16–4.09) and high total cholesterol (AOR = 3.15, CI 1.68–5.92). After a median of 3.0 years of ART, the mean eGFR declined from 112.9 ± 81.2 ml/min/1.73m2 at baseline to 93.9 ± 60.6 ml/min/1.73m2 (P < 0.001). The prevalence of renal impairment increased from 19.8% at baseline to 22.1% during follow-up. Of 181 patients with baseline normal renal function, 49.7% experienced some degree of renal impairment. Older age (AOR = 3.85, 95% CI 2.03–7.31), female sex (AOR = 4.18, 95% CI 2.08–8.40), low baseline CD4 (AOR = 2.41, 95% CI 1.24–4.69), low current CD4 count (AOR = 2.32, 95% CI 1.15–4.68), high BMI (AOR = 2.91, 95% CI 1.49–5.71), and low hemoglobin (AOR = 3.38, 95% CI 2.00–7.46) were the factors associated with renal impairment during follow-up. Conclusion Impaired renal function was common in HIV-infected patients initiating ART in an outpatient setting in Ethiopia, and there appears to be a high prevalence of renal impairment after a median ART follow-up of 3 years. There is a need for assessment of renal function at baseline before ART initiation and regular monitoring of renal function for patients with HIV during follow-up.


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Although the incidence of HIV-associated renal impairment has decreased in the recent ART 92 period, the proportion of renal impairment has increased due to increasing burden of comorbid 93 renal impairment risk factors such as diabetes and hypertension in this aging population (12-14).

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The increase in the incidence of renal impairment could also be related to the long-term exposure 95 to potentially nephrotoxic antiretrovirals, such as tenofovir, ritonavir-boosted atazanavir, and    and percentages, and continuous variables were summarized by mean ± standard deviation (SD).

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Univariate analyses to assess factors associated with renal impairment at baseline and during 137 follow-up were tested using Chi-square test and student's t-test, where appropriate. Variables that 138 were found to be significant in univariate analysis (P < 0.25) were included in the multivariate  Twenty-seven (7.6%) patients had a history of diabetes or hypertension at baseline.    The proportion of patients with eGFR = 60-89.9 ml/min/1.73m 2 increased by 10.2% after ART.

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Our findings are comparable to some of the studies in the region regarding the prevalence of renal 222 impairment at baseline prior to ART initiation using the same definition with MDRD formula 223 (21,27). Other studies showed highly variable prevalence according to the racial distribution, impairment (eGFR < 60 ml/min/1.73 m 2 ) of 3.0%, 3.3%, 5% and 24%, respectively at baseline 227 before ART initiation using the same MDRD formula for eGFR. These findings were concerning 228 given reports that impaired renal function at baseline is an independent predictor of death and renal 229 disease progression in HIV-infected patients (4,5).

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Our study documented risk factors for renal impairment (eGFR < 60 ml/min/1.73 m 2 ) in patients 231 with HIV at the baseline prior to ART initiation that are similar to those identified by previous 232 studies including female sex, low CD4 count, low BMI, and low hemoglobin (21,29,(31)(32)(33)(34). In 233 this study, older age at baseline was also significantly associated with increased risk of renal 234 impairment before initiating ART in univariate analyses, but did not obtain statistical significance 235 in multivariate analysis. Multiple previous studies in cohorts of HIV-positive subjects initiating 236 ART reported older age as a strong risk factor of impaired renal function at treatment initiation 237 (21,29,30,(32)(33)(34). Interestingly in our study we found higher total cholesterol associated with  The present study also revealed a decline in mean eGFR after ART initiation, from a mean eGFR 259 of 112.9 ± 81.2 ml/min/1.73 m 2 at baseline to 93.9 ± 60.6 ml/min/1.73 m 2 after a median ART infected patients on ART. Similar to the South African study, a high BMI has been identified as a 285 risk factor for renal impairment in our patients after ART initiation (31).

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Lower baseline CD4 count has also been identified as risk factors for renal impairment after ART 287 initiation. This is consistent with findings from related studies, which reported that lower baseline 288 CD4 count may have an additive effect on renal impairment risk in HIV infected patients after 289 ART initiation (21,29,40,43). We found no significant differences in renal impairment among First, this is an observational cohort study and not a randomized clinical trial. Second, some 306 clinical indicators of renal health or treatment (e.g. proteinuria and viral loads) were not available 307 in our database and are not included in this cohort. Third, although subjects in this analysis were 308 exposed to multiple ART regimens, the effects of specific ART regimens on renal function was