Comparison with similar studies
According to this study, the overall prevalence of CKD among HAART naïve and experienced HIV patients was 119 (19.3%) with 95% C.I (16.2 to 22.4). This finding was found to be consistent with different studies conducted in Queen Elizabeth Hospital, the tertiary referral centre in Hong Kong, China (16.8%),51 Gondar (16.1%)31 and Jimma (18.2%).35 However, the prevalence of CKD in this study was lower as compared with different studies conducted in Nigeria (38%),52 Côte d’Ivoire (26%),53 Zambia (33.5%)54 and Kenya (25%).55 In contrast to this, the result was higher as compared with the report from Belgium (3.0%),56 Brazil (8.4%)57 and Ghana (10.8%).58 This discrepancy might be due to different populations, study designs, variation in sample size, a definition used to define CKD and use different estimating formulas of GFR may contribute to the differences observed.
In this study, the prevalence of CKD among HAART naïve HIV patients was (29.3%) with 95% CI (21.65 to 36.92). It is comparable to different studies conducted in Tanzania (25%),59 Blantyre, Malawi 23%60 and in different parts of Ethiopia; (31.1%) in Felege Hiwot Referral Hospital61 and 28.7% in Jimma University Specialised Hospital (JUSH).35 However, the prevalence of this study was higher than different studies conducted in other African countries; 20% in Uganda,62 8% in Lusaka, Zambia63 and 3% in Cameroon.64 This variation might be due to the difference in the study setting, inclusion and exclusion criteria of the study participants, sample size, the definition used to define CKD and formulas used to eGFR. For instance, in Kenya, participants with known sickle cell disease, acute infection, previously diagnosed diabetes, marked hypertension or renal disease were excluded, and in Lusaka, Zambia the renal function was calculated using Cockcroft Gault formula, and only patients initiated on tenofovir containing drugs were included.
The prevalence of CKD among HAART experienced HIV patients was 78 (16.4%) with 95% CI (13.1 to 19.7). This study was comparable with the study conducted in Ghana (14.5%).58 However, this study finding is higher as compared with studies reported in Tanzania (1.1%),65 Uganda (6%),62 in the University of Gondar Hospital, Ethiopia (11.7%),33 in JUSH, Ethiopia, (7.6%),35 in Felege Hiwot Referral Hospital, Ethiopia (12.1%).61 This wide variation could be attributed to the differences in the HAART regimen, and the method used to eGFR. For instance, in Tanzania, adjusted the Cockroft-Gault equation was used to calculate eGFRs, and may contribute to the differences observed. But in our study, eGFR was calculated using the CKD-EPI equation which is the most accurate for the staging of CKD at all levels of eGFR.17
The prevalence of CKD was significantly higher in naive study participants than HAART experienced study participants. This finding is supported by researches done in Nigeria,66 Jimma35 and Bahir Dar Ethiopia.61 The finding of lower CKD prevalence in HAART experienced study participants may be due to the improvement in renal function because of HAART drugs. In the current study, different predictors were found to be significantly associated with both CKD among HAART naïve and CKD among HAART experienced HIV patients.
The rural residency was found to be a strong predictor variable for both CKD among HAART naïve and CKD among HAART experienced HIV patients. This is supported by the study conducted in SSA,67 and other low-income and middle-income countries.68 This is due to the fact that the use of herbal medicines is commonly practiced in rural communities of both Africa and Asia which can also act as nephrotoxins, thus increasing the risk of CKD progression.69 Moreover, in low-income and middle-income countries, most populations are rural residing communities where awareness of CKD remains low and also recognising problems associated with CKD are ill-equipped particularly during the early asymptomatic stages of the disease.70 Worldwide, only one-third of people with CKD are diagnosed in rural communities and are more prone to develop different complications due to unavailability and unaffordability of health services like laboratory investigations and different treatments.71 Furthermore, this might be due to the burden of travelling long distances to access health services, costs of accommodation and perceived lack of education regarding their kidney disease and treatment options.72 Moreover, associated with the unavailability of health services in rural community, the low provision of drugs and poor adherence check-up will contribute for CKD to appear more common in rural community.
In this study, being anaemic was also significantly associated with both CKD among HAART naïve and CKD among HAART experienced HIV patients. Similarly, this finding was supported by the study conducted in Nigeria.52 Anaemia occurs commonly in CKD among HIV patients as the result of decreased production of erythropoietin which is responsible for the production of red blood cells73 either due to functional or absolute iron deficiencies.74 Moreover, anaemia in CKD among HIV patients has been associated with opportunistic infections and inflammation,75 micronutrient deficiencies, medication-induced and neoplastic diseases.76
Similarly, this study revealed that being hypertensive and advanced WHO clinical stage were also significantly associated with both CKD among HAART naïve and CKD among HAART experienced HIV patients, respectively. This finding was corroborated by studies conducted in Brazil57 and Nigeria.77 Previous study report by Ibrahim et al confirmed that the likelihood of developing kidney disease among hypertensive patients on HAART was almost fivefold,78 where hypertension inhibits the immune status of patients with HIV which in turn may increase in viral load and renal dysfunction.79 Similarly, patients with late-stage of HIV diagnosis were at risk of high viral load which in turn may affect the renal function.9
Consumption of drinking water per day below recommended amount was an important factor which determines CKD among HAART experienced HIV patients. Similarly, this finding was supported by a study conducted in Ontario, Canada.80 This is due to the fact that lower levels of water intake cause decreased urine output which may increase the supersaturation of calcium phosphate, calcium oxalate and uric acid, which finally increases the risk of stone formation and eventually predisposes to CKD.81
Obesity was also another factor significantly associated with CKD among HAART-experienced HIV patients. This finding was supported by a study conducted in China.82 This is explained by the fact that traditional risk factors like obesity, diabetes and hypertension are global contributing factors for CKD.83 This is because, in obese individuals, there is an increased metabolic demand of the increased body weight, resulting in glomerular hyperfiltration, hypertrophy and intraglomerular pressure, subsequently predisposed to CKD.84
Furthermore, having a family history of kidney disease was also another factor significantly associated with CKD among HAART naïve HIV patients. This finding was in line with the study in the Netherlands.85 This might be because of some hereditary kidney diseases like autosomal-dominant polycystic kidney disease which is caused by genetic changes of PKD1 gene located on chromosome 16 encoding membrane protein polycystin which is responsible for maintaining of renal epithelial differentiation and organisation, where this function is disrupted by mutations in PKD1 which probably leads to abnormal differentiation of tubular cells and cyst formation. Therefore, this mutated gene can be inherited by family members and causes enormous kidney problems.86 87
However, in this study, the current status of DM remains insignificant among HAART naïve, HAART experienced, and overall all HIV patients, the study conducted in Jordan revealed that being diabetic was the strong significant factor for CKD due to the reason that DM cause long-term microvascular and macrovascular complications, contributing to the increased morbidity of CKD.88 This discrepancy might be due to the reason that in this study, the total numbers of diabetic participants who developed CKD are very rare, and this could contribute for this variable to remain insignificant when adjusted. Moreover, since the average time of onset of kidney impairment in patients with diabetes is about 7–10 years, in this study, patients with diabetes might not be chronically ill for such duration of time. Furthermore, this discrepancy could also be due to the difference in; the follow-up time, severity of DM, the timing of initiation of treatment, treatment options, early recognition of risk factors and symptoms, and availability of health services.89
Statistically significant difference was observed in the mean value of GFR level between HAART naïve and HAART experienced HIV patients, where the mean value of GFR level among HAART experienced HIV patients exceeds the mean value of GFR level among HAART naïve HIV patients. This is due to the fact that the HAART regimen has a positive impact on the increment of GFR level. In contrast to this, the GFR level among HAART naïve was decreased. This might be explained by the fact that HAART naïve HIV patients are commonly at risk of advanced HIV disease where high viral load is common, and this will contribute to the decrement of GFR which turns to cause severe stage of CKD. As to the researchers’ knowledge, no comparative study was done to discuss.
Similarly, there was also a statistically significant difference in the mean value of Current CD4+ T-cell count (cells/mm3) between HAART naïve and HAART experienced HIV patients. This is due to the reason that HAART naïve patients are affected by the high viral load which depletes the level of CD4+ T-cell count.
This study was conducted in the three hospitals and increases the probability of generalisability of CKD among HIV patients. However, this study has its own limitation. First, since this study was the cross-sectional study, it did not show the cause and effect relationship of variables. Second, there will be lower risk prediction due to the reason that some biomarker like cystatin C was not tested to estimation of GFR. Third, there will be poor sensitivity and high false-discovery rates due to the reason that proteinuria was assessed using dipstick not the albumin-creatinine ratio. Therefore, this study results should be interpreted with caution.