Prevalence of newly diagnosed hypertension in patients presenting with stroke at the medical emergency Department of Rwanda Military Referral and Teaching Hospital: a five-years retrospective study (2020–2025)

Abstract

Background

Hypertension is a leading modifiable risk factor for stroke, especially in low- and middle-income countries. In Rwanda, stroke remains a significant public health concern; however, local data on the epidemiological profile of hypertension among stroke patients are limited. This study aimed to assess the prevalence and characteristics of newly diagnosed hypertension in patients presenting with stroke at the Medical Emergency Department of the Rwanda Military Referral and Teaching Hospital.

Methods

This retrospective study reviewed the records of 227 stroke patients admitted from June 2020 to May 2025 at RMRTH. Data on demographics, hypertension status, adherence, stroke type, and admission blood pressure were collected. The Analyses used SPSS version 27 with descriptive statistics, 95% CIs, and subgroup comparisons by hypertension status, age, and sex.

Results

The median age of the patients was 65 years, and 66.1% were male. Ischemic stroke was the predominant subtype, accounting for 58.1% of cases. Hypertension was highly prevalent: 59.0% had a prior diagnosis, 23.3% were newly diagnosed upon admission, and only 17.6% had no hypertension. Among patients with known hypertension, 93.2% reported poor adherence to antihypertensive medication. The mean admission blood pressure was highest in patients with newly diagnosed hypertension (166/100 mmHg), followed closely by those with known hypertension (163/99 mmHg), while normotensive patients had lower mean values (128/82 mmHg). Poor medication adherence was associated with a significantly higher mean blood pressure (165/100 mmHg) compared with good adherence (144/90 mmHg). Additionally, males had a slightly higher mean blood pressure than females (161/96 mmHg vs. 151/97 mmHg, respectively).

Conclusion

This study reveals a substantial burden of both diagnosed and undiagnosed hypertension among patients presenting with stroke in Rwanda. The high prevalence of poor adherence to antihypertensive therapy and elevated blood pressures at presentation suggest a critical need for enhanced community-based hypertension screening and timely linkage to care. Tailored interventions targeting early detection and improved medication adherence could significantly reduce stroke incidence and improve outcome.

Background

Stroke is a neurological disorder characterized by an acute disruption of cerebral blood flow to specific regions of the brain, resulting in focal or global neurological deficits due to ischemic or haemorrhagic injury [1]. The increasing burden of morbidity and mortality is significantly associated with stroke worldwide. Hypertension is clinically defined as a sustained elevation of systolic blood pressure (BP) to 140 mmHg or higher or a diastolic BP to 90 mmHg or higher, based on standardized blood pressure measurements. Hypertension is a well-established modifiable risk factor for stroke, with the incidence and severity of cerebrovascular events showing a direct correlation with the degree of elevated blood pressure [1, 2]. Another study revealed that elevated blood pressure is responsible for nearly two-thirds of all stroke cases, with the majority resulting from undiagnosed, untreated, or poorly managed hypertension [3]. Stroke-related mortality increase in direct proportion to elevated blood pressure levels. Among hypertensive individuals, cerebrovascular complications more strongly associated with systolic blood pressure than with diastolic blood pressure [4]. Stroke is the second leading cause of death globally, accounting for approximately 11.8% of all death and each year, approximately five million people—primarily in developed countries—die as a result of stroke [2]. Hypertensive individuals often exhibit inadequate blood pressure control despite the availability of antihypertensive medications [5]. Furthermore, hypertension frequently remains undiagnosed during its early stages and may persist for extended periods, becoming clinically apparent only when serious complications develop [6]. In developing countries, the prevalence of hypertension is estimated at 20%, with approximately 14.4% of cases remaining undiagnosed, indicating a significant burden of asymptomatic or subclinical hypertension [7, 8]. The risk of stroke can be reduced by up to 38% through effective management and prevention of hypertension [9].

Despite a few studies from neighbouring countries, there are currently no published data from Rwanda quantifying the burden of hypertension among patients presenting with acute stroke. At Rwanda Military Referral and Teaching Hospital (RMRTH), acute stroke is a common emergency, yet the clinical patterns and prevalence of hypertension in these patients remain poorly characterized. This lack of epidemiological insight hinders effective planning, timely intervention, and evidence-based policy development. Community-based screening in Rwanda revealed a surprisingly high prevalence of newly diagnosed hypertension—18.7% in rural and younger populations, and 15% in the Ndera sector [10]. Early identification and effective management of hypertension, a major cardiovascular risk factor, play a critical role in reducing the burden of stroke. Therefore, the current study aimed to determine the epidemiology of hypertension among patients admitted with acute stroke at the Rwanda Military Referral and Teaching Hospital.

Method

Aim of the study

To determine the prevalence of newly diagnosed hypertension in Patients Presenting with Stroke at the Medical Emergency Department of Rwanda Military Referral and Teaching Hospital.

Study design

This was a quantitative, retrospective, descriptive cohort study of adult patients aged 18 years and above who presented to the emergency department at RMRTH with stroke from the 1st of June 2020 to the 30th of May 2025.

Study protocol

Ethical approval for this study was obtained from the Institutional Review Board (IRB) of the Rwanda Military Referral and Teaching Hospital prior to commencement. Given that this was a retrospective chart review, informed consent could not be obtained from individual patients. A waiver of consent was therefore formally requested through a research proposal to the Institutional Review Board (IRB).

Inclusion criteria

• All patients aged 18 years and above presented with acute stroke, confirmed by brain computed tomography (CT) imaging, irrespective of prior hypertension history.

Exclusion criteria

• Incomplete or missing medical records that limited adequate data extraction.

• Pregnant patients, owing to the unique physiological changes, aetiologies, and clinical management of hypertension during pregnancy.

• Patients with a history of trauma preceding the onset of stroke symptoms.

This study was a retrospective descriptive review of all patients admitted with a diagnosis of stroke to the Emergency Department of Rwanda Military Referral and Teaching Hospital (RMRTH) between June 2020 and May 2025. Eligible cases were identified through admission and discharge registries, and corresponding electronic records were retrieved through the Open Clinic System, with paper charts consulted where necessary. All available stroke records were screened using predefined inclusion and exclusion criteria. A substantial number of potential cases were excluded because of incomplete or missing clinical information, absent blood pressure measurements, incomplete triage documentation, or missing imaging reports. In addition, a notable proportion of patients were counter-referred to district hospitals for conservative management immediately after initial evaluation when their initial presentation did not indicate the need for surgical intervention or thrombolytic therapy; complete clinical records for these cases were unavailable. As all eligible cases during the study period were included, a prior sample size calculation or power analysis was not applicable.

Stroke diagnosis was primarily based on non-contrast CT brain imaging, as MRI was not routinely available during the study period and radiologist adjudication was not systematically documented. Stroke was defined using AHA/ASA (2019) criteria. Transient ischemic attack (TIA) was defined as a transient episode of neurological dysfunction resulting from focal cerebral, spinal cord, or retinal ischemia, in the absence of acute changes on CT imaging. Hypertension status was determined using documented blood pressure measurements recorded during hospital admission. Newly diagnosed hypertension was defined as persistently elevated blood pressure (≥ 140/90 mmHg) documented on at least three separate measurements, obtained at a minimum of 15-minute intervals, to minimize misclassification related to acute stress, intercurrent illness, or the white-coat effect.

Medication adherence was assessed using information extracted from clinician-documented entries in the Open Clinic System and paper charts. These entries reflected patient-reported adherence obtained during routine clinical assessments and, where available, supporting information such as medication refill history, prior outpatient blood pressure trends, or transfer notes from referring district hospitals. Some patients were also being routinely followed at RMRTH for hypertension, providing longitudinal data on adherence and blood pressure control.

No validated adherence tools were available for retrospective assessment. The data collection was completed using a structured form to record demographics, age, history of hypertension, medication adherence, admission blood pressure, and type of stroke. Descriptive statistics were calculated. Continuous variables are presented as mean ± standard deviation, and categorical variables as counts and percentages.

Study setting

This study was conducted at the Rwanda Military Referral and Teaching Hospital (RMRTH), a tertiary-level healthcare institution located in the Kicukiro District of Kigali, the capital city of Rwanda. As one of the leading referral centers in the country, RMRTH operates within a multidisciplinary and teaching-oriented framework, providing both specialized and general medical services. The hospital serves a dual population of military personnel and civilians, with its catchment area primarily including Kigali city and the Eastern Province. Owing to its strategic location and comprehensive range of services, RMRTH functions as a critical referral point for complex medical emergencies, including acute stroke cases. RMRTH has a capacity of approximately 500 inpatient beds and is equipped with diagnostic and treatment facilities that support the management of neurological emergencies. The hospital includes dedicated departments for internal medicine, surgery, neurology, radiology, and critical care.

Measurements

Vital signs, including blood pressure, were measured at triage for all patients presenting to the emergency department (ED), as part of routine clinical care. Blood pressure was assessed via a calibrated digital monitor (Philips SureSigns VS2+), which is standard equipment in the ED triage area.

Data analysis

SPSS version 27 was used for data analysis. Categorical variables such as sex, history of hypertension, adherence to antihypertensive drugs and type of stroke were calculated and expressed in terms of frequency and percentage. Numerical variables such as age (years) and blood pressure are presented as the means and standard deviation. Continuous variables are presented as mean ± standard deviation, and categorical variables as counts and percentages.

Results

Patient demographics and clinical characteristics

A total of 227 stroke patients were enrolled, with a median age of 65 years (range 21–100), and a mode of 84 years, indicating a predominance of elderly patients (Table 1). Males accounted for 66.1% of the cases, whereas females represented 33.9%. The mean age was slightly greater in males (66.9 years) than in females (64.3 years).

Table 1.

Descriptive statistics for age, systolic BP, and diastolic BP

Parameter	Age (years)	Systolic BP (mmHg)	Diastolic BP (mmHg)
Mean	65.98	157.90	96.59
Median	65.00	156.00	96.00
Mode	84.00	150.00	90.00
Standard Deviation	17.93	32.86	21.18
Range	79.00	188.00	150.00
Minimum	21.00	78.00	40.00
Maximum	100.00	266.00	190.00

Hypertension prevalence and blood pressure profiles

Overall, 82.3% of patients had hypertension. Of these, 59.0% had a previously known diagnosis based on self-reported history documented in their medical records, while 23.3% were newly identified during admission using repeated blood pressure measurements. Only 17.6% had no documented hypertension. Blood pressure at admission was markedly elevated in most patients. Over half (58.2%) had a systolic blood pressure (SBP) above 150 mmHg, including 26.9% with severe hypertension (> 180 mmHg). Only 3.5% presented with SBP ≤ 100 mmHg. Diastolic blood pressure (DBP) was moderately elevated (71–100 mmHg) in 52.0% of patients, with 34.8% having a DBP between 101 and 130 mmHg, and 5.7% exhibiting severe diastolic hypertension (> 130 mmHg) (Fig. 1A and B).

Fig. 1.

A. Frequency distribution of systolic blood pressure categories. B. Frequency distribution of diastolic blood pressure categories

Males had a higher mean SBP (161.1 mmHg) than females did (151.7 mmHg), whereas females had a slightly higher mean DBP (97.5 mmHg vs. 96.1 mmHg in males). The mean SBP and DBP across all patients were 157.9 mmHg and 96.6 mmHg, respectively.

Stroke subtypes and blood pressure association

Ischaemic stroke was the most common subtype (58.1%), followed by haemorrhagic stroke (37.0%) and transient ischaemic attack (4.8%). Patients with ischemic stroke were older on average (mean 68.3 years) than those with haemorrhagic stroke (61.5 years) or TIA (71.8 years) (Table 2).

Table 2.

Age distribution by type of stroke in the study population

Type of Stroke	N	Mean Age (years)	Standard Deviation
Ischemic stroke	132	68.31	17.80
Haemorrhagic stroke	84	61.54	17.44
Transient ischemic attack	11	71.81	17.93
Total	227	65.98	17.93

Haemorrhagic stroke patients presented with significantly greater mean SBP (174.3 mmHg) and DBP (104.5 mmHg) than did ischemic stroke patients (SBP 147.7 mmHg, DBP 91.7 mmHg) and TIA patients (SBP 155.4 mmHg, DBP 94.8 mmHg).

Medication adherence and hypertension control

Among patients with known hypertension (n = 134), documented self-reported poor adherence was common (93.2% of those with an adherence entry), with only 6.7% reporting good adherence, noting that this was based on routine clinical documentation rather than validated adherence instruments. Across the entire study, 55.1% of patients had a poor adherence, while 40.5% had either newly diagnosed hypertension or no prior hypertension treatment (Fig. 2).

Fig. 2.

Frequency distribution of medication adherence

Behavioural risk factors

One-third of patients (33.0%) had a history of smoking, and 59.5% reported alcohol consumption. Both factors contribute to stroke risk and poor blood pressure control.

Stroke recurrence

Recurrent stroke was documented in 8.4% of patients, while 91.6% experienced a first-ever stroke.

Age and hypertension status

Patients with existing hypertension were older (mean 68.8 years) than were those with newly diagnosed hypertension (60.2 years) or no hypertension (64.0 years). The study population had a mean age of 66.0 years (SD = 17.9), with ages ranging across all adult decades. Patients with existing hypertension were older on average (mean = 68.9 ± 15.8 years) than were those with newly diagnosed hypertension (mean = 60.2 ± 20.1 years) and those without hypertension (mean = 64.0 ± 20.0 years) (Table 3).

Table 3.

Descriptive statistics for age by hypertension status

Hypertension Status	N	Mean Age (years)	Standard Deviation
New hypertension	53	60.24	20.10
Existing hypertension	134	68.85	15.76
No hypertension	40	63.97	20.01
Total	227	65.98	17.93

Figure 3 illustrates the age distribution of the participants, with the highest frequency observed in the > 80 years’ age group, followed by the 51–60 and 61–70 years’ age categories.

Fig. 3.

Frequency distribution of age categories

Discussion

The current study investigated the prevalence of newly diagnosed hypertension among stroke patients who presented to the emergency department. Overall, 82.3% of patients had hypertension. Overall, hypertension was identified in 82.3% of stroke patients, with 59.0% (134 patients) having a prior diagnosis and 23.3% (52 patients) being newly diagnosed at the time of stroke presentation. The remaining 17.6% had no indication of hypertension. When stratified by hypertension status, 72% of hypertensive stroke cases occurred in patients with previously known hypertension, whereas 28% were among those newly diagnosed.

Stroke was defined as a sudden onset of a neurological deficit caused by brain infarction (ischemic stroke) or hemorrhage (haemorrhagic stroke), regardless of symptom duration, with evidence of tissue injury [11]. A transient ischemic attack (TIA) is defined as a transient episode of neurologic dysfunction due to focal brain, spinal cord, or retinal ischemia without acute infarction or tissue injury [12]. Stroke is more common in men, accounting for approximately 60% of cases, whereas in women it represent approximately 40% cases [13].

A previous study highlighted nonmodifiable risk factors including age, sex, and ethnicity, whereas modifiable risk factors included hypertension (65%), diabetes mellitus (36.3%), dyslipidemia (32.7%), smoking (32%), and obesity (18%) [14].Ischaemic stroke can be prevented through proper control of blood pressure and blood sugar, the use of antiplatelet and lipid-lowering medications, and the adoption of healthy lifestyle habits. Additionally, the overall incidence of stroke can be reduced by addressing controllable risk factors, as fixed factors such as age and genetics cannot be altered [15, 16].

Hypertension remains a dominant modifiable risk factor for stroke, and undiagnosed hypertension represents a growing public health burden, particularly in low- and middle-income countries. In Ethiopia, the pooled prevalence of undiagnosed hypertension varies between 15.4% and 28.8%, as demonstrated in systematic reviews, meta-analyses, and cross-sectional studies [17, 18].

Stroke risk increases proportionally with both systolic and diastolic blood pressure across all age groups and in both sexes, with systolic pressure having the greatest impact. A 10 mmHg increase in systolic blood pressure and diastolic values exceeding 110 mmHg has been linked to a 25% greater risk of stroke, whereas a 10 mmHg reduction in systolic pressure is associated with a 41% lower risk of stroke [19, 20].Factors contributing to uncontrolled hypertension may include resistant hypertension, adverse drug effects, inadequate medical care, and poor adherence to therapy [21, 22].

Patients with newly identified hypertension presented higher average blood pressure levels (167/101 mmHg), than did those with previously diagnosed hypertension (160/98 mmHg) and normotensive individuals (132/84 mmHg). Additionally, the average age at first stroke is approximately 73 years, with men experiencing strokes at a mean age of 65 years and women at approximately 73 years [23].

Ischaemic stroke has emerged as the most common subtype, accounting for approximately 87% of all stroke cases, whereas haemorrhagic strokes—including intracerebral and subarachnoid haemorrhages—comprised the remaining 13% [24]. The mean systolic blood pressure at admission varied by stroke subtype, with ischemic stroke patients having an average systolic blood pressure of 154 mmHg. In contrast, those with haemorrhagic stroke had a higher average of 176 mmHg [25].TIA comprises approximately 5–15% of all cerebrovascular events, although it is likely underdiagnosed in many regions [26]. TIA represents a large proportion of minor cerebrovascular events and is associated with a high short-term risk of stroke (up to 12% within 1 year) [27]. The prevalence of transient ischaemic attacks (TIAs) is not consistently quantified in many studies, particularly in low- and middle-income countries, where they are often underdiagnosed owing to limited access to neuroimaging and specialist evaluation. The prevalence of undiagnosed hypertension among otherwise healthy individuals ranges between 4.8% and 8% according to other epidemiological studies [28–30].

Limitations

This study relied on retrospective medical records, which inherently depend on the completeness and accuracy of routine clinical documentation. Many records were incomplete or missing essential clinical, imaging, or triage data, thereby introducing selection bias and resulting in the exclusion of numerous potential cases. Additionally, a significant proportion of patients were counter-referred to district hospitals shortly after triage, meaning that subsequent diagnostic evaluations, treatments, and outcomes occurred outside the study facility, and their full clinical information was unavailable for extraction. Collectively, these factors reduced the final sample size and may limit the generalizability of the findings to other healthcare settings or populations.

Stroke diagnoses were based primarily on CT imaging using non-contrast protocols, without MRI availability or formal radiologist adjudication, which increases the likelihood that small ischemic lesions, early ischemic changes, or transient ischemic attacks were missed or misclassified. Medication adherence assessment was limited to clinician-documented information in medical records, which may not accurately reflect true patient adherence, and no validated adherence tools were available for retrospective use. Lifestyle factors such as smoking and alcohol use were inconsistently documented, limiting the ability to control for these potential confounders in the analysis. As all eligible cases during the five-year period were included, a prospective sample size calculation was not applicable, and the study may therefore have limited statistical power for certain subgroup or exploratory analyses.

Conclusion

The primary aim of this study was to determine the prevalence of newly diagnosed hypertension among patients presenting with stroke at a tertiary referral hospital in Rwanda. Our findings show that 23.3% of stroke patients had previously undiagnosed hypertension, suggesting a notable burden of unrecognized hypertension within this hospital-based population. Ischemic stroke was the most common subtype (58.1%), while hemorrhagic stroke was observed at a proportion higher than that reported in many international studies. Males were more affected, and hemorrhagic stroke patients had the highest admission blood pressure values. These results underscore the potential value of strengthening hypertension screening and control efforts to support stroke risk reduction and potentially improve outcomes.

Given Rwanda’s rapidly evolving healthcare capacity, including expanded MRI availability, future prospective, multicenter studies are recommended. Such studies should incorporate standardized hypertension assessment protocols, validated medication adherence tools, and advanced imaging to enhance diagnostic accuracy, facilitate broader stroke surveillance, and better inform targeted prevention strategies.

Abbreviations

IRB

instructional review board

RMRTH

Rwanda military referral and teaching hospital

SBP

systolic blood pressure

DBP

diastolic blood pressure

TIA

transient ischaemic attack

Authors’ contributions

A.I.M, O.U, I.N: Conceptualization, Project administration, Writing-review and DesigningA.I.M, O.U, I.N, F.M: Reviewed and edited the first draftManuscript writing: A.I.M, O.U, I.N, F.MO.U: Reviewed and edited the second draftA.I.M: Reviewed and edited the third draftO.U: Revised, Reviewed and edited the final draftFinal approval of manuscript: A.I.M, O.U, I.N, F.MA.I.M was responsible for data collection and investigation. F.M performed the formal analysis and contributed to the development of methodology. All authors were involved in drafting the manuscript, critically revising it for important intellectual content, and approved the final version of the manuscript.

Funding

We have not received any financial support for this manuscript.

Data availability

The datasets used and/or analysed during the current study are available from the corresponding author upon reasonable request.

Declarations

Ethics approval and consent to participate

Ethical approval for this study was obtained from the Institutional Review Board of the Rwanda Military Referral and Teaching Hospital (RMRTH-IRB), reference number 215/RMRTH/COMDT/2025, prior to the initiation of the study. As this was a retrospective chart review, obtaining informed consent from individual patients was not feasible. A formal request for waiver of consent was submitted and granted by the Institutional Review Board of the Rwanda Military Referral and Teaching Hospital. This waiver was approved in accordance with national research ethics guidelines and the ethical principles outlined in the 1964 Helsinki Declaration and its later amendments.

Consent for publication

Not Applicable.

Competing interests

The authors declare no competing interests.