Original Articles
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https://doi.org/10.4081/hls.2026.14227

Linear mixed models for evaluating CD4+ count progression and its predictors: a four-year longitudinal study at Yekatit 12 Referral Hospital, Ethiopia

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Received: 6 August 2025
Accepted: 23 September 2026
Published: 23 October 2026
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ART, CD4+, longitudinal data, missing data, linear mixed model, missing at random

Authors

Kebadu Tadesse Cherie
kebadu.tadesse@dmu.edu.et
Department of Statistics, Debre Markos University, Debre Markos, Ethiopia.

Despite significant improvement in the use of antiretroviral therapy, HIV/AIDS remains to be one of the major public health challenges in Sub-Saharan African countries including Ethiopia. The main objective of the study was to identify factors associated with progression of CD4+ cell counts of HIV patients on ART. A longitudinal data was extracted from SMARTCARE of patients on ART from September 2009 to January 2016 in Yekatit 12 referral Hospital. The data was analyzed using linear mixed model taking correlation between CD4+ counts of patients into account. We included 217 patients of whom 65% were females and only 51.61% of patients were followed until the last follow up time. The missingness in the data was handled using direct likelihood and multiple imputation approaches. Results from the two methods were found to be comparable. Thus, baseline WHO clinical stage, time on treatment and the interaction effects of sex, age, baseline CD4+ count and regimen class with time were found significantly associated with progression of CD4+ count. We concluded that HIV/AIDS patients should be put on ART at early stages despite their baseline CD4+ cell count and treatments should be taken continuously to improve the progression of CD4+ count.

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Ethics Approval

Ethical clearance and approval for this study were obtained from the Institutional Review Board (IRB) of the College of Natural and Computational Sciences, Addis Ababa University. Following this, a formal letter of support and administrative permission were granted by the Yekatit 12 Hospital Medical Case Team. To ensure patient confidentiality, all data were extracted from the ART clinic registries by trained data clerks using anonymized abstraction forms. The research team did not have access to any personal identifiers or original patient medical cards. The study was conducted in accordance with the Declaration of Helsinki and the national guidelines for research involving secondary clinical data.

Supporting Agencies

This work was supported by Addis Ababa University under grant GSR/1172/07.

Data Availability Statement

The anonymized data used to produce results reported in this manuscript could be obtained from the corresponding author Mr. Kebadu Tadesse Cherie (Email: kebadu.tadesse@dmu.edu.et).

How to Cite



Linear mixed models for evaluating CD4+ count progression and its predictors: a four-year longitudinal study at Yekatit 12 Referral Hospital, Ethiopia. (2026). Healthcare in Low-Resource Settings. https://doi.org/10.4081/hls.2026.14227
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