# Investigating the Risk Factors in Progression of HIV Disease Using an Illness-Death Multistate Model

## TL;DR

This study examines how risk factors affect the progression of HIV disease using a multistate model to track transitions between health states.

## Contribution

The study introduces a multistate model to analyze HIV progression, incorporating intermediate events and risk factors.

## Key findings

- Receiving ART significantly reduces the risk of transitioning from HIV to AIDS.
- TB co-infection increases the risk of transitioning from HIV to AIDS and from AIDS to death.
- Early diagnosis and adherence to treatment can reduce AIDS progression and mortality.

## Abstract

The trend of human immunodeficiency virus (HIV) disease progress is different for every patient. Some patients may experience events during the course of their disease that can affect disease progression and death. The main objective of the present study was to investigate the effect of risk factors in progression of HIV disease, taking into account intermediate events, using a multistate model.

A retrospective cohort study.

The current study used information from 673 HIV-infected adult patients registered at the Hamadan Provincial Health Center in Iran, between 1997 and 2023. A multistate framework was described to investigate the progression of HIV disease over time. Three states (HIV-infected, acquired immunodeficiency syndrome [AIDS], and death) and three possible transitions (from HIV to AIDS, from HIV to death, and from AIDS to death) were considered in this framework. An illness-death multistate model was applied to determine the effect of risk factors on these transitions.

The results revealed that receiving antiretroviral therapy (ART) significantly decreased the hazard of transition from HIV to AIDS, whereas older age, tuberculosis (TB) co-infection, and treatment with the final guideline intensified the hazard of the mentioned transition. Low education, older age, and unprotected sexual transmission increased the risk of transition from HIV to death, while receiving ART and treatment with the final guideline decreased the risk of this transition. Receiving ART, being employed, having a history of prison, and being treated with the final guideline could decrease the hazard of transition from AIDS to death, whereas TB co-infection increased the hazard of this transition.

Implementing strategies for early diagnosis, timely treatment, adherence to treatment, as well as screening and TB treatment, especially at younger ages, can be useful in reducing AIDS progression and mortality.