Published in PLOS One on 2026-08-05, this study is presented as an attributed evidence briefing. The excerpts below are the original researchers’ words, reproduced under their Creative Commons Attribution licence. Health Signal has selected the abstract and, where needed, opening background paragraphs; the complete methods, results, limitations and references remain in the linked paper.
Original authors: Benedicto T Mgala, Salome E Buluba, Aisha A Omar, Dickson A Mkoka, Redoy Ranjan, Mergan Naidoo
Source: PLOS One • DOI 10.1371/journal.pone.0355506
Read the complete primary study ↗ · Creative Commons Attribution licence
From the researchers
Abstract
Long-term warfarin therapy following prosthetic heart valve placement is essential for preventing valve-related thromboembolic complications. Due to its narrow therapeutic window, maintaining a therapeutic International Normalized Ratio (INR) requires strict adherence to healthcare medication, dietary recommendations, and regular monitoring. Despite receiving education at discharge, patients with prosthetic heart valves continue to demonstrate poor adherence to warfarin therapy. While previous quantitative studies have identified factors associated with non-adherence, little is known about patients’ day-to-day experiences and challenges with long-term warfarin use in low-resource settings.
This study explored day-to-day experiences and challenges encountered during long-term warfarin use among patients with prosthetic heart valves attending a National Cardiac Institute in Dar es Salaam, Tanzania.
An explorative qualitative study design using inductive content analysis was conducted among twelve (12) patients with prosthetic valves on long-term warfarin therapy, who were purposively recruited based on the principle of data saturation between April 2025 and June 2025 at a national cardiac institute. In-depth interviews were conducted using a semi-structured interview guide. Data were analyzed manually using a deductive-inductive content analysis approach.
Two main categories emerged from this study. The first category, adapting to life with long-term warfarin use, describes participants’ experiences of symptom relief and improved quality of life after surgery, alongside issues related to dietary restrictions, medication side effects, emotional distress, and reduced engagement in socio-economic activities. Participants perceived dietary recommendations as restrictive and reported difficulties with lifestyle modifications required during long-term warfarin therapy. The second category, navigating warfarin care within an unstructured continuum of care, reports participants’ struggles in maintaining therapeutic INR levels amid financial difficulties, inconsistent medication use, contradictory information from healthcare providers, and limited access to INR monitoring and warfarin services in peripheral regions. Some participants reported self-adjusting warfarin doses or missing follow-up appointments due to cost and accessibility barriers.
Although participants experienced clinical improvement post-surgery, they continued to face substantial challenges related to long-term warfarin use and access to anticoagulation care. Strengthening patient-centered education, improving continuity and consistency of anticoagulation counselling, decentralizing warfarin and INR monitoring services, and enhancing structured long-term follow-up systems may improve warfarin adherence and patient outcomes in low-resource settings.
Introduction
Valvular heart disease (VHD) is a leading global cause of cardiovascular symptoms and functional disability, contributing to an estimated 1.4 million deaths and over 10 million disability-adjusted life years annually [1–3]. While degenerative and functional VHD dominate in high-income countries, rheumatic heart disease (RHD) caused by rheumatic fever remains the primary form in low- and middle-income countries [4]. In 2019, the global prevalence of RHD was estimated at 40.5 million, with the highest burden among marginalized populations in sub-Saharan Africa (SSA) [2,4]. Rheumatic heart disease complicating to VHD remains highly prevalent in Tanzania, with pooled estimates around 9% and echocardiographic studies reporting subclinical valvular diseases in approximately 2–3% of school-aged children, highlighting a substantial disease burden [1,5,6].
Reading this evidence
Use the full paper to check the study design, participant selection, comparator and outcome definitions before drawing a practical conclusion. An association does not by itself show cause and effect. A reported performance measure needs its denominator and uncertainty. A finding from a particular facility, sample or time period should retain that scope when it is discussed elsewhere.
This briefing makes the source accessible within the wider research & evidence desk. It does not assess an individual patient or certify a product. When considering relevance to another health system, examine the original authors’ account of context and limitations, then seek local implementation evidence. The related reporting below provides other studies to read alongside this one; it is a topic connection, rather than a claim that their results are directly comparable.
© 2026 Benedicto T Mgala, Salome E Buluba, Aisha A Omar, Dickson A Mkoka, Redoy Ranjan, Mergan Naidoo. Excerpts reproduced under CC BY. Selection, formatting and contextual notes by Health Signal. The researchers are the authors of the source study, not members of Health Signal’s staff.
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