At a primary health centre in Ndola, Zambia, only 41.4% of 237 hypertensive patients achieved adequate adherence to antihypertensive medication, measured via the modified Hill-Bone Compliance Scale. Multivariable logistic regression identified age ≥51 years (AOR 2.89–3.24), secondary or tertiary education (AOR 2.84–3.56), and monthly income ≥1,000 Kwacha (AOR 2.21–5.89) as protective factors, while medication side effects (AOR 0.36), regimen complexity (AOR 0.34), and comorbidities (AOR 0.51) significantly undermined adherence. Structural barriers compounded the picture: 38.4% experienced drug stock-outs, and nearly half received under five minutes of counselling per visit.
These findings land within a well-documented sub-Saharan adherence crisis — regional non-adherence estimates range 45–65% — but the granularity here on health-system failures is notable. The counselling-time data particularly stands out: five minutes or less is inadequate for any chronic disease education, and this structural deficit is modifiable through task-shifting and group-based care models proven effective in similar low-resource settings. The strong income gradient reinforces that hypertension control in low-income countries is as much an economic problem as a pharmacological one. Practically, these results argue for simplified fixed-dose combination regimens, community drug distribution, and SMS-based reminders — all tested interventions that could address the forgetting and running-out-of-pills barriers cited most frequently. Important limitations include the cross-sectional design, single-site recruitment, and self-report bias. As a preprint not yet peer-reviewed, these findings should be treated as hypothesis-generating until independent validation confirms them.