High blood pressure (hypertension) remains one of the major public health problems worldwide, constituting the most important risk factor for cardiovascular morbidity and mortality, particularly for coronary heart disease, stroke, and chronic kidney disease. It is estimated that about 1.3 billion people suffer from hypertension, two-thirds of whom live in low- and middle-income countries (LMICs). Despite the availability of effective treatments, the proportion of diagnosed, treated, and properly controlled hypertensive patients remains low, especially in sub-Saharan Africa, where less than a quarter of hypertensive individuals are aware of their blood pressure status [1, 2, 3, 4].

In Senegal, the prevalence of hypertension has been estimated to be between 25% and 30% among adults, according to data from STEPS surveys and local studies. However, most cases remain undiagnosed or poorly controlled due to limited access to screening, the cost of care, lack of regular follow-up, and poor treatment adherence [5].

In the face of these challenges, community interventions such as screening campaigns, education, and awareness-raising play a crucial role in early detection, promoting health-friendly behaviors, and improving treatment adherence. These initiatives, often carried out in collaboration between healthcare facilities, local communities, and community organizations, help reach populations that are distant from the formal healthcare system. However, most community interventions are evaluated using post-intervention cross-sectional assessments, limiting the ability to quantify changes attributable to educational activities [6].

In this context, the GHPL Laboratory conducted a screening and awareness campaign on hypertension and cardiovascular risk factors in the municipality of Malicounda (Mbour health district, Senegal). This study aims to fill the gap in local data on the immediate effectiveness of this type of intervention.

The main objective of this work was to :

• Describe the epidemiological and clinical profile of the campaign participants ;
• Identify the independent determinants of hypertensive status in this sample ;
• Assess changes in knowledge, attitudes and perceptions before and after the intervention.

Methodology

Study design and setting

This was a quasi-experimental pre-post study without a control group. Participants were recruited among adults attending the campaign and were not sampled from the general population of Malicounda.

Population and sampling

The study included 291 adult participants (volunteers over 18 years old) who underwent screening and awareness activities. The sampling was based on convenience, including anyone who agreed to respond to the questionnaire. No formal sample size calculation was performed because the study included all eligible adults attending the campaign who consented to participate during the study period. Data were collected at two time points: before the educational session (pre-test) and immediately after the intervention (post-test).

Data collection and operational definitions of variables :

The data were collected using a structured questionnaire with :

• Socio-démography: age, sex, educational level.
• Clinic: blood pressure measurement and BMI calculation (weight/height²).
• Cardiovascular risk factors: medical history, smoking, dietary habits, stress, physical activity.
• KAP: Assessment of knowledge, attitudes (Likert scale for intention to change), and impact perceptions (Parts B to E of the questionnaire).

The questionnaire was specifically developed for this study by the research team in collaboration with members of the Department of Public Health and experienced professionals in public health and epidemiology. The content was developed according to the study objectives and covered sociodemographic characteristics, clinical characteristics and cardiovascular risk factors, as well as knowledge, attitudes, preventive intentions and perceptions related to hypertension. The questionnaire was reviewed by the research team and public health experts to assess the relevance, clarity and comprehensiveness of the items and their appropriateness to the local context. Any necessary modifications were made before field administration.

Assessment of knowledge, attitudes and perceptions

Knowledge, attitudes and perceptions related to hypertension and cardiovascular risk prevention were assessed using a structured questionnaire administered immediately before and immediately after the educational session. The questionnaire included several domains covering participants' knowledge of hypertension and its cardiovascular risk factors, attitudes and intentions toward preventive behaviours, and perceptions of the educational intervention.

Knowledge was assessed using a seven-item score. Each correct response was assigned one point, resulting in a total score ranging from 0 to 7, with higher scores indicating greater knowledge. Individual knowledge items addressed major hypertension risk factors, including salt intake, smoking, diabetes, stress and physical inactivity.

Attitudes and preventive intentions were assessed using Likert-scale questions addressing participants' willingness to adopt preventive behaviours, including regular blood pressure monitoring and adoption of a healthier diet.

Perceptions of the intervention were assessed using questions addressing participants' perceived improvement in their understanding of cardiovascular risk factors and preventive measures, as well as their intention to maintain preventive monitoring after the campaign.

The same questionnaire was administered before and immediately after the educational session, allowing comparison of paired responses. The assessment focused on immediate changes in knowledge, attitudes and perceptions and did not measure sustained behavioural change or long-term clinical outcomes.

Definition of hypertension: Systolic blood pressure of 140 mmHg or higher and/or diastolic blood pressure of 90 mmHg or higher, and/or a declared status of taking antihypertensive treatment. So we distingue three situations :

measured hypertension : SBP ≥140 and/or DBP ≥90 mmHg ;

known hypertension : self-reported previous diagnosis or current antihypertensive treatment ;

hypertension status : measured hypertension and/or known hypertension.

BMI (body mass index) calculated by dividing weight by the square of height. Its normal value is between 18.5 and 24.9. Globally : underweight <18.5 ; normal 18.5–24.9 ; overweight 25.0–29.9 ; obesity ≥30 kg/m² [1].

Statistical analysis

The data were analyzed using descriptive statistics (means with standard deviation, frequencies, and percentages).

• Bivariate analysis: Chi-squared test (χ²) or Fisher's exact test and Student's t-test to compare variables between hypertensive and non-hypertensive groups.
• Multivariate analysis: A multiple logistic regression was conducted to identify factors independently associated with hypertension (variables included: age, sex, diabetes, smoking). The significance threshold was set at (p < 0.05).
• McNemar's exact test was used to compare paired categorical variables, whereas paired Student's t-test was used to compare continuous variables.

Ethical Considerations

The study got approval from the health research ethics committee at Iba Der Thiam University of Thiès. Informed consent was obtained from all participants. Anonymity and data confidentiality were respected.

Results

Demographic and clinical characteristics

The sex ratio was 0.75 with a female predominance (57.0%).

Figure 1: Distribution of Respondents by Gender

291 participants included out of the 339 targeted by the campaign, average age 48,2 ± 10,1 years (table I).

Table I: Socio-demographic data of participants

Figure 2: Distribution by age group

Determinants of Hypertension: bivariate and multivariate analysis

Bivariate analysis revealed significant associations between hypertension and age over 50, diabetes, and smoking. After adjustment in multiple logistic regression, only two determinants retained an independent association.

The main risk factors identified by the participants were dominated by unhealthy eating and excessive salt intake (170 mentions). Age was cited by 155 people. Stress was frequently reported (149 mentions), followed by diabetes (147) and smoking (146), two major recognized risk factors. A family history of hypertension was mentioned by 144 respondents, indicating an awareness of the role of heredity. And the lack of regular physical activity appeared in 131 participants, reflecting notable sedentary behavior in the population studied (table II).

Table II: Participants' recognition of hypertension risk factors before and immediately after the awareness intervention

Advanced age and known diabetes are the strongest determinants of hypertension in this population. The effect of smoking loses its independence after adjustment for age and diabetes.

Table III: Independent determinants of hypertension