Justine L. Vasco

Introduction: Cardiovascular diseases remain a major cause of morbidity and mortality in sub-Saharan Africa; however, little is known about inpatient cardiovascular medicine utilisation in Tanzania. This study quantified cardiovascular medicine utilisation patterns at a national cardiac referral centre using the standardised WHO ATC/DDD methodology. Methods: A retrospective longitudinal pharmacoepidemiological study was conducted using inpatient prescription data from the Jakaya Kikwete Cardiac Institute (JKCI) for the fiscal years 2016/2017 to 2021/2022. Non-medicinal items and topical formulations were excluded from the analyses. Utilisation was expressed as Defined Daily Doses (DDD) per 100 bed-days using the WHO ATC/DDD methodology. Descriptive statistics and non-parametric tests were performed using SPSS version 26. Results: Of the 290,591 prescription records screened, 224,290 were eligible following the exclusion of 64,781 non-medicinal items and 1,520 topical agents. Cardiovascular medicines (ATC class C) accounted for 99,634 (44.4%) of all prescriptions, followed by alimentary tract and metabolism agents (18.1%). The prescribing volumes increased annually and peaked in 2021/2022. Furosemide (C03CA01), spironolactone (C03DA01) and paracetamol (N02BE01) were the three most frequently prescribed medicines. The 12 most commonly used medicines represented approximately half of all the prescriptions. Conclusion: Cardiovascular medicines accounted for nearly half of all inpatient prescriptions, reflecting the substantial clinical demand and disease burden associated with cardiovascular conditions. Utilisation was dominated by loop and potassium-sparing diuretics, highlighting their central role in inpatient cardiac care. Routine surveillance using ATC/DDD metrics should be institutionalised to guide procurement, prescribing audits, and patient safety monitoring. Trial registration number Not applicable. What is already known on this topic: The incidence of cardiovascular diseases is increasing globally, with increasing medicine use in both high-and low-income settings. Evidence of inpatient cardiovascular medicine consumption in sub-Saharan Africa is limited to a few studies. Previous pharmacoepidemiological studies from SSA have mainly focused on antibiotics rather than medicines for chronic noncommunicable diseases. What this study adds”: This is the first longitudinal analysis of inpatient cardiovascular medicine use in Tanzania based on ATC/DDD. Nearly half of all inpatient prescriptions at the national cardiac referral centre were cardiovascular agents, predominantly diuretics. These findings establish a baseline for stewardship, informed procurement decisions, and future national monitoring efforts.

Background: Cardiovascular diseases are among the leading causes of morbidity and mortality worldwide. Routine quantification of cardiovascular medicine utilisation is essential for stewardship, formulary decision-making and procurement planning. Objective: To describe outpatient utilisation of cardiovascular medicines at the Jakaya Kikwete Cardiac Institute (JKCI) using ATC/DDD methodology. Methods: This was a retrospective longitudinal analysis of outpatient prescriptions (2017/2018-2021/2022). Medicines were classified according to the ATC system and quantified as Defined Daily Doses (DDD) per 100 outpatient days. The analyses progressed hierarchically from ATC levels 1 to 5. DU metrics (DU50/DU90) were used to assess the concentration. Monthly utilisation was examined using Seasonal Trend decomposition using Loess (STL). Statistical analyses were performed using SPSS (version 26). Results: Across the study period, the cumulative utilisation of cardiovascular medicines totalled 360.55 DDD per 100 outpatient days. Annual intensity peaked in 2018/2019 (82.92 DDD per 100 outpatient-days), was the second-highest in 2020/2021 (82.39), and was lowest in 2017/2018 (55.68). At ATC level 5, amlodipine (C08CA01), candesartan (C09CA06) and clonidine (C02AC01) were the principal contributors. The DU50 segment comprised five molecules (amlodipine, candesartan, clonidine, furosemide, and atorvastatin), whereas DU90 ranked 18th, indicating concentrated utilisation within a small number of agents. The STL showed a gradual secular rise with no statistically significant month-specific seasonality. Conclusion: Outpatient cardiovascular medicine utilisation at JKCI was concentrated within a narrow set of anti-hypertensive agents, with a cumulative burden of 360.55 DDD per 100 outpatient-days and a fiscal-year peak in 2018/2019. Institutionalising routine outpatient DDD surveillance may support stewardship, rational prescribing, and more equitable access to high-impact cardiovascular medicines in Tanzania.