The results of this study has shown that in the current era of HAART in Nigeria, majority of the hospitalised HIV-infected patients are heterosexuals of young productive age and that most of the newly diagnosed HIV-infected patients as well as patients receiving ART are hospitalised on account of AIDS-defining illnesses characterised by severe immunosuppression and anaemia. These findings possibly reflect late HIV diagnosis and delay in initiation of HAART. It is worrisome that even with the provision of free ARV drugs in many parts of Sub-Saharan African many HIV/AIDS patients from this region still suffer from advanced HIV-related diseases [16
], whereas in the developed world, morbidity is mainly due to HIV-unrelated diseases [17
]. To facilitate early HIV diagnosis and early initiation of HAART, all stakeholders in the region must make concerted effort to expand and implement voluntary counselling and testing as well as the provider-initiated testing and counselling, even as new strategies are developed to detect early infection for prompt initiation of HAART, when necessary.
Although the morbidity and mortality of HIV/AIDS in Nigeria are known to predominantly affect females [1
], our study revealed that more males than females were admitted and died of HIV/AIDS. Higher hospitalisation of males than females has also been reported in other hospital-based studies of HIV-infected and noninfected populations from northern Nigeria [2
]. In our environment, the family economic power rest with the men and it is likely than women is underrepresented because very sick women either never get to the hospital or die before decisions are made to take them to the hospital. We cannot tell if the observed male preponderance in some aetiological diagnoses was also due to these reasons. It is also not clear why our newly diagnosed HIV-infected patients without ART experience were younger that the patients receiving ART, but it may probably be due to the time lag between HIV diagnosis and initiation of ART. However, in agreement with other studies [2
], our male patients were older than the females irrespective of ART status. This finding has been attributed to earlier sexual maturity in females and, therefore, earlier risk of acquisition of HIV infection in females than males [22
In studied participants, we observed a variety of HIV-related and unrelated manifestations, but tuberculosis, followed by sepsis and chronic diarrhoea, were the most common causes of morbidity in both groups of patients. This spectrum of clinical presentations is similar to that reported in an earlier study of hospitalised HIV/AIDS patients in our region in the pre-HAART era [23
], as well as studies from other parts of Nigeria [2
] and other resource-limited settings [25
] in the HAART era. In view of the heightened risk of TB coinfection in HIV-infected patients, there is a critical need to foster and strengthen TB/HIV collaborative services in Nigeria, like in many other Sub-Saharan countries where both infections are endemic. Consistent with other studies [27
], Kaposi's sarcoma (KS) was the most common malignancy and cerebral toxoplasmosis was the most common cerebral mass lesion in our patients, although aetiological causes for some cases of focal deficits could not be established. Toxoplasmosis and HHV8 infection, the causative agent for KS, are both endemic in Nigeria [29
], and in our region, HHV8 infection have been shown to be more prevalent in HIV-infected patients than HIV negative individuals [31
]. Consequently, government and other stakeholders in Nigeria ought to develop locally suitable and comprehensive preventive and management guidelines for these endemic infections, especially in HIV-infected patients.
Possibly reflecting the benefits of HAART in reducing rates of hospitalisation [32
], only few of our hospitalised patients were receiving ART. The majority of these patients were admitted for AIDS-defining illnesses due to ART treatment failure as well as for direct ART-related complications such as IRIS and drug toxicities. AZT-induced severe anaemia requiring blood transfusions was the most common reason for admission. Hence, patient on this drug ought to be closely monitored for anaemia as well as for other related ART adverse reactions such as lactic acidosis, peripheral neuropathy, and lipodystrophy which have been reported among outpatients in our region [9
]. As efforts are made to scale up HAART to reach more than 500,000 individuals with advanced HIV in Nigeria who are currently not receiving HAART [1
], stakeholders in Nigeria must begin to recognise and tackle challenges such as ARV drug resistance and poor ART adherence known to fuel ART treatment failure, even as future studies investigate the risk factors for IRIS and ARV drug toxicities in adult Nigerians.
Although some differences in study design exist, the overall mortality rate of 31.8% observed in our study population is comparable to the mortality rates of 26 to 40% reported in other studies of hospitalised HIV/AIDS patients during the HAART era from Nigeria [2
] and other resource-limited settings [21
]. Like in our study, late presentation and advanced HIV as reflected in low CD4 cell counts were factors implicated for the reported high mortality rates in these studies. Although not reaching statistical significance, possibly due to small sample size, the median duration of HAART before death in our ART-experienced patients was 3 months as compared to 10 months for those that survived. This finding is in agreement with other studies that have shown that mortality is highest in the first 3 months of HAART [35
In our patients, PCV was found to be independently associated with mortality with a six-fold risk of mortality in patients with severe anaemia. This finding corroborates studies from other developing countries [35
], as well as developed countries where anaemia was also found to be an independent predictor of mortality in HIV/AIDS patients [38
]. Anaemia is marker of progressive HIV disease as it is a prominent feature of most opportunistic infections complicating HIV-disease, including TB [39
]. In the setting of HIV/AIDS, anaemia may result from micronutrient deficiencies, immunological myelosuppression, impaired erythropoietin production, and blood loss from intestinal opportunistic disease, among other causes [39
]. Since assessment of PCV is simple and rapid, routine screening for anaemia in resource poor settings can be a cost-effective tool for identifying high-risk HIV/AIDS patients for closer followup and targeted interventions.
There are limitations to our study. First, since the study was retrospectively designed, detailed clinical and laboratory variables were not available for all patients. However, we believe the missing data did not significantly affect the major outcomes of the study since our findings were comparable to those within and outside Nigeria. Data quality can be improved by future prospective studies from Nigeria to clarify the independent associations, if any, between variables such as CD4 and platelet counts, and mortality of hospitalised HIV/AIDS patients in Nigeria, as shown by studies from other parts of Africa [35
Second, we could not confirm the causes of deaths in most patients because of lack of permissions for autopsies. However, the listed causes of death were standardized and further validated during mortality reviews. The aetiological causes of sepsis could also not be confirmed by positive blood cultures possibly because most patients often practise self-medication or receive antibiotics elsewhere before hospitalisation, making cultures negative. However, culture of microorganisms such as mycobacteria and other atypical microorganisms reported to cause sepsis in HIV-infected patients [40
] are not routinely done in our centre due to resource constraints. Third, since serial viral loads were not available for most patients on HAART, it is plausible that some cases of virological failure without concomitant clinical failure would have been missed. Furthermore, in the absence of reliable records, it was impossible to decide from patient's retrospective records if poor ART adherence contributed in any way to treatment failure. Lastly, given that outcome measure for our study depended on the survival status as at last contact with our patient in the hospital, we cannot exclude an underrepresentation of mortality rate as some DAMA patients might have died outside our hospital.