Modeling multistage transition probability in blood pressure progression stages among hypertensive patients, southern Ethiopia: A retrospective cohort study

Introduction: Hypertension is the primary cause of cardiovascular death and a major contributor to heart attack, stroke, chronic heart disease, and kidney failure. The aim of this study was to estimate multistage transition probability and identify associated risk factors among hypertensive patients. Methods: A total of 210 patients who underwent hypertension treatment follow-up at Hawassa University Comprehensive Specialized Hospital (HU-CSH) were included in the study. The multistate Markov model is used to estimate transition probability, transition intensity between disease stages, and mean time spent in each BP progression stage. We used the proportional hazards regression model to estimate effects of different covariates on transition intensity within and between BP progression stages. Results: Among the total study participants, 56.7% were female and 43.3% were male; of these, 66.2% were urban and 33.8% were rural residents. The transition probability from stage 1 to stage 2 was 0.151, from stage 2 to stage 3 was 0.128, and from stage 3 to stage 4 was 0.205. Stage 3 had the shortest estimated mean sojourn time. Old-aged (30+) patients had 3.19 times (19%) more risk of transitioning from stage 2 (grade 1 hypertension) to stage 3 (grade 2 hypertension) compared to patients below 30 years of age. Conclusion: Patients who were in stage 3 (grade 2 hypertension) had a higher risk of progressing to stage 4 (grade 3 hypertension). A family history of hypertension, older age (30+), male sex, urban residence, history of previous hypertension and diabetes were major risk factors of hypertension and increased BP.