Abstract
Background
Hypertension (HTN) is a major public health issue in Sri Lanka, influenced by genetic predisposition and lifestyle factors. Despite high general literacy, gaps in health literacy and suboptimal HTN management persist. Understanding knowledge, attitudes, and practices (KAP) in HTN is crucial for developing targeted public health interventions to improve awareness and management.
Methods
A cross-sectional online survey was conducted among Sri Lankan adults from February to September 2024. Participants were recruited via social media, and data were collected using a structured questionnaire assessing socio-demographic characteristics, knowledge of HTN, attitudes toward prevention and treatment, and health-related practices. Knowledge scores were analysed using descriptive statistics, chi-square tests, ANOVA, and regression models.
Results
A total of 2,013 participants were included, with 47% diagnosed with HTN. The mean knowledge score was 57 ± 20%, with 36% of respondents scoring below 50%. Awareness of risk factors varied—while 78% recognized excessive salt intake, only 40% identified alcohol consumption as a risk factor. Knowledge of HTN consequences was uneven; 87% identified heart disease, but only 31% recognized eye disease as a complication. Urban residents and those with higher education and income had significantly better knowledge scores, while misconceptions about HTN, such as water intake being a risk factor (21%), were prevalent. Attitudes toward HTN management were generally positive, with 81% recognizing the importance of treatment adherence, though only 48% acknowledged weight loss as a preventive measure. Regular blood pressure monitoring was reported by 81%, with individuals diagnosed with HTN being 7.3 times more likely to check their BP regularly (OR: 7.28, 95% CI: 4.67–11.35, p < 0.001). Salt reduction practices were influenced by socioeconomic factors, with urban residents being 2.2 times more likely to add salt (OR: 2.21, 95% CI: 1.56–3.12, p < 0.001).
Conclusion
Despite Sri Lanka’s high general literacy, significant gaps exist in HTN knowledge and practices. Public health strategies should focus on improving health literacy, addressing misconceptions, and promoting behavioural change through targeted interventions, particularly among socioeconomically disadvantaged populations.
Supplementary Information
The online version contains supplementary material available at 10.1186/s12889-025-23592-5.
Keywords: Hypertension, Health literacy, Sri Lanka, Public health, Hypertension management
Background
Hypertension (HTN), recognized as chronically elevated blood pressure (BP), is a widespread global health issue, causing significant morbidity and mortality [1]. Its impact extends beyond observed prevalence, with profound effects on an individual’s quality of life and productivity, together with a significant strain on healthcare systems globally [1]. The World Health Organization estimates that 10 million annual deaths are attributable to elevated BP, more than any other risk to health, highlighting its global burden [2]. Uncontrolled elevated BP serves as a precursor to various other debilitating health conditions, including cardiovascular diseases and chronic kidney disease [3]. Furthermore, cognitive decline has been linked with HTN, underscoring concerns about its impact on mental well-being [4]. Low- and middle-income countries bear a disproportionate burden of HTN, primarily due to lifestyle factors, with South Asians facing a particularly high risk, due to super-imposed genetic predisposition [5].
High prevalence of undiagnosed HTN [6], sub-optimal treatment due to therapeutic inertia [7] and non-adherence to treatment [8] are other challenges faced globally in the HTN care cascade. Lack of understanding among individuals regarding the importance of maintaining normal levels of BP and/or the adverse consequences of untreated or poorly managed HTN, combined with poor knowledge about medications, their proper use, potential adverse effects, and the overall benefits of adherence to prescribed treatment regimens, are significant contributors to suboptimal HTN management [9]. Health literacy plays a crucial role in enabling individuals to comprehend medical advice, follow treatment plans, and make informed decisions about their health, especially in the management of chronic conditions such as HTN [10]. Health literacy interventions, such as mobile health applications delivering educational interventions have demonstrated effectiveness on improving adherence to medications and control BP in those with HTN [11]. Therefore, it is evident that the knowledge of and attitudes to HTN in a population are key determinants of health outcomes, particularly in improving adherence to treatment, achieving optimal BP control, and reducing cardiovascular consequences of HTN. Hence, it is essential to assess and understand the knowledge of and attitudes to HTN at the population level.
Sri Lanka is a middle-income nation in the South Asian region, home to a population of 21 million, that is experiencing a steady increase in the prevalence of HTN, especially in urban areas [12, 13]. A recent cohort study from a tertiary care hospital in Sri Lanka identified a high prevalence of uncontrolled hypertension and cardiovascular morbidity [14]. Sri Lanka is recognized for its high general literacy rate, which is among the highest in South Asia, often exceeding 90% in the overall population and being as high as 99% among the Sri Lankan youth. However, despite the high general literacy, health literacy (the ability to understand, access, and use health information for informed decision-making) remains a significant challenge in Sri Lanka. For instance, a study among school teachers in the Colombo Education Zone found that 32.5% had ‘limited’ health literacy, highlighting a significant gap despite overall educational attainment [15]. The poor health literacy in Sri Lanka, despite its high general literacy rate, is likely to have significant implications for managing chronic conditions like HTN.
Understanding the knowledge of, attitudes to, and practices (KAP) in HTN among the Sri Lankan population will be crucial for designing effective public health interventions. Carefully planned KAP surveys provide valuable insights into misconceptions and barriers to behavioural change [16, 17]. It is important that such surveys capture a wider audience representative of the country’s population, being not limited to single health-care settings or populations. Given the widespread prevalence of HTN in Sri Lanka, an online survey method can offer extensive reach and scalability, to identify important factors related to gaps in KAP in the population. Therefore, the present study aims to assess KAP in HTN among both people with self-reported hypertension and the general normotensive population in Sri Lanka, including understanding of its causes, risk factors, and potential consequences.
Methods
Study design and participants
A cross-sectional online survey was conducted to assess KAP related to HTN among Sri Lankan adults. Data collection was carried out through an online questionnaire hosted on Google Forms. (Supplementary File 1) The study population comprised adults aged 18 years or older who were Sri Lankan citizens residing in Sri Lanka at the time of the survey and included self-reported hypertensive and normotensive individuals. Participants were recruited over an eight-month study period (February to September 2024) through convenience sampling, where participants were selected based on their availability and willingness to participate, with survey links shared online as described below under recruitment of participants. Convenience sampling was deemed the most pragmatic choice in this online survey as it enabled efficient and cost-effective data collection. Ethical approval for the study was obtained from the Ethics Review Committee, Faculty of Medicine, University of Colombo (EC-23–047). To ensure anonymity and confidentiality, personal details, including email addresses, were not collected. Electronic informed consent was obtained prior to survey completion, and responses were securely stored on the Google platform, with access only available to the investigators. A minimum sample size of 2000 was deemed adequate for the online KAP survey, to ensure precise and reliable estimates of the population’s knowledge, attitudes, and practices. Additionally, it is sufficient to supports subgroup analyses by demographic factors, captures the heterogeneity of responses, and accounts for the typically low response rates in online surveys.
Recruitment of participants
Multiple strategies were used to recruit participants. The survey link was shared through social media networks, including WhatsApp, Facebook, Twitter, and Instagram, and through the professional contacts of research team members. Social media groups representing diverse professional and interest backgrounds were strategically targeted to enhance representativeness. Participants were encouraged to share the survey link within their social media networks and WhatsApp groups. All participants received a link to hypertension-related health education material upon completion of the survey. The survey was shared until the required sample size was fulfilled.
Study instrument and definitions
The self-administered questionnaire was made available in English, Sinhala, and Tamil, allowing participants to select their preferred language. It took approximately 10–15 min to complete. Face validity was confirmed by two independent clinicians, who reviewed the content and scoring accuracy. A pilot study involving 10 randomly selected individuals was conducted to test question clarity, scoring reliability, and the need for any language revisions in the Sinhala and Tamil versions to improve understandability before the survey. The questionnaire included four sections. Section 1 contained socio-demographic information, while Sect. 2 evaluated healthy behaviour/practices related to BP, such as salt intake and physical activity. Practices were assessed prior to knowledge and attitudes to prevent response bias. The amount of alcohol consumed per week was classified as non-drinking (abstention), occasional/drinking only in social situations, or regular drinker. Amount of activity was classified as very little activity, only chores, regular (at least 150 min per day) of either low, moderate or heavy intensity activity. Corresponding examples were given for each level of activity as reference. Section 3 evaluated knowledge of HTN, and included an open-ended question on normal BP, and questions regarding risk-factors for HTN and consequences of uncontrolled HTN. (Supplementary File 2) The final section looked at attitudes to HTN, which were measured using a five-point Likert scale, addressing views on controlling salt intake, the importance of fruit and vegetables in the diet, weight management, regular BP checks, physical exercise, and the likelihood of serious complications from poor HTN management.
Data analysis
Data were analysed using SPSS software (version 25). Categorical variables were presented as frequencies and percentages, while continuous variables were summarized using mean and standard deviation (SD). Knowledge scores were quantified using specific criteria and described in detail in Supplementary File 1. Accordingly, the maximum knowledge score was 28 points, expressed as a percentage in the analysis. The associations between these scores and participant demographics were tested using bivariate and multivariate analyses.
Associations between the score for knowledge of HTN and participant characteristics were tested using chi-square analyses, with subgroup analyses by sex. Spearman’s correlation was employed to examine associations between age, and knowledge scores, while one-way analysis of variance (ANOVA) tests with post-hoc analyses were done to compare knowledge scores across multiple categories. Significant variables from the bivariate analyses were included in linear regression models to identify predictors of HTN knowledge. Analyses were conducted separately for hypertensive and normotensive participants. Linear regression was also employed to examine predictors of key HTN-related practices, specifically regular BP monitoring and the addition of excess salt to food. Model fit and significance were assessed using the Hosmer-Lemeshow and Omnibus tests respectively. Variables were entered using the Backward Wald method to develop final models including only significant predictors. The Nagelkerke-R² statistic was calculated to indicate the model’s explanatory power, and odds ratios (OR) were derived from the exponentiated B coefficients for each predictor. In all analyses a p value < 0.05 was considered significant.
Results
Characteristics of the study population
We analysed data from a total of 2013 respondents. As presented in Table 1, the gender distribution was balanced, with men comprising 48.8% (n = 983). The mean age was 47.7±13.1 years (Men: 48.0±13.4 years; Women: 47.3±12.8 years). Almost half (46.8%; n = 943) of the participants were diagnosed with HTN (Men: 54.2% [n = 511]; Women: 45.8% [n = 432]), with a noTable 69.6% of the total population (n = 1401) reporting a family history of HTN. A substantial majority (73.9%) lived outside Colombo district, Sri Lanka’s commercial capital. Other socio-demographic characteristics are summarised in Table 1. Few noteworthy disparities existed between men and women: women were more likely to be unemployed (41.8% vs. 31.9%), although a larger proportion of women had attained a diploma or degree-level education compared to men.
Table 1.
Sociodemographic features of the study population
| Number (%) | |||
|---|---|---|---|
| All (n=2013) | Men (n=983) | Women (n=1030) | |
| District | |||
| Colombo | 526 (26.1) | 232 (23.6) | 294 (28.5) |
| Outside Colombo | 1487 (73.9) | 751 (76.4) | 736 (71.5) |
| Urban/Rural | |||
| Urban | 1002 (49.8) | 465 (47.3) | 537 (52.1) |
| Rural | 1011 (50.2) | 518 (52.7) | 493 (47.9) |
| Marital status | |||
| Unmarried | 495 (24.6) | 224 (22.8) | 271 (26.3) |
| Married | 1518 (75.4) | 759 (77.2) | 759 (73.7) |
| Education | |||
| None | 6 (0.3) | 3 (0.3) | 3 (0.3) |
| Primary | 23 (1.1) | 5 (0.5) | 18 (1.7) |
| G.C.E. Ordinary Level (Secondary) | 251 (12.5) | 145 (14.8) | 106 (10.3) |
| G.C.E. Advanced Level (Secondary) | 826 (41.0) | 418 (42.5) | 408 (39.6) |
| Diploma/ degree or higher (Tertiary) | 907 (45.1) | 412 (41.9) | 495 (48.1) |
| Employment status | |||
| Employed | 1268 (63.0) | 669 (68.1) | 599 (58.2) |
| Unemployed | 745 (37.0) | 314 (31.9) | 431 (41.8) |
| Ethnicity | |||
| Sinhala | 1809 (89.9) | 872 (88.7) | 937 (91.0) |
| Tamil | 90 (4.5) | 59 (6.0) | 31 (3.0) |
| Moor | 94 (4.7) | 44 (4.5) | 50 (4.9) |
| Other (Malay, Burgher) | 20 (1.0) | 8 (0.8) | 12 (1.2) |
| Monthly income | |||
| <LKR50,000 (USD 167) | 644 (32.0) | 317 (32.2) | 327 (31.7) |
| ≥LKR50,000 | 1369 (68.0) | 666 (67.8) | 703 (68.3) |
Knowledge of hypertension
Among respondents, the mean knowledge score was 57.3±20.1% (range: −5.2 to 100.0). The scores were higher among women (58.0±20.0%) than men (56.5±20.2%) (p = 0.079). When considering individual domains evaluated under knowledge, the mean risk factor knowledge score was 46.9±25.7% (range: −10.0 to 90.0), while the mean score for knowledge about the consequences of HTN was 46.4±26.8% (range: −25.0 to 100). As shown in Table 2, the most recognized risk factor was excess salt intake (77.6%, n = 1562), while only 39.9% (n = 803) identified excess alcohol consumption as a risk factor. Misconceptions existed as well; for example, 21.1% (n = 425) mistakenly believed water intake to be a risk factor. Heart disease (87.4%, n = 1759) and stroke (76.4%, n = 1200) were well-recognized consequences, whereas only 30.8% (n = 621) identified eye disease as an outcome of untreated HTN. Although a majority (91.5%) acknowledged HTN as a condition requiring treatment, only 51.9% (n = 1044) knew the correct normal BP value, which was only marginally higher in individuals with HTN (54.5%, n = 514).
Table 2.
Knowledge, attitudes and practices related to hypertension
| Number (%) | |||
|---|---|---|---|
| All (n=2013) | Men (n=983) | Women (n=1030) | |
| Knowledge of the normal BP value | 1044 (51.9) | 475 (48.3) | 569 (55.2) |
| Knowledge of risk factors | |||
| Excess salt intake | 1562 (77.6) | 729 (74.2) | 833 (80.9) |
| Excess alcohol use | 803 (39.9) | 408 (41.5) | 395 (38.3) |
| Excess water intake (misconception) | 425 (21.1) | 206 (21.0) | 219 (21.3) |
| Knowledge of consequences | |||
| Heart disease | 1759 (87.4) | 860 (87.5) | 899 (87.3) |
| Stroke | 1200 (76.4) | 569 (71.2) | 631 (81.7) |
| Eye disease | 621 (30.8) | 306 (31.1) | 315 (30.6) |
| Renal failure | 788 (39.1) | 395 (40.2) | 393 (38.2) |
| Attitudes | |||
| Importance of weight loss | 968 (48.1) | 432 (43.9) | 536 (52.0) |
| Importance of fruit/vegetable intake | 1316 (65.4) | 603 (61.3) | 713 (69.2) |
| Importance of treatment adherence | 1630 (81.0) | 785 (79.9) | 845 (82.0) |
| Practices | |||
| Regular BP checking | 1624 (80.7) | 813 (82.7) | 811 (78.7) |
| Adds excess salt to meals | 258 (12.8) | 129 (13.1) | 129 (12.5) |
| Regular smoking habits present | 141 (7.0) | 116 (11.8) | 25 (2.4) |
| Alcohol consumption | |||
| Not consuming | 1493 (74.2) | 600 (61.0) | 893 (86.7) |
| Social (occasional) drinking | 342 (17.0) | 240 (24.4) | 102 (9.9) |
| Regular | 178 (8.8) | 143 (14.5) | 35 (3.4) |
| Level of activity | |||
| Very little and irregular | 478 (23.7) | 201 (20.4) | 277 (26.9) |
| House chores only | 912 (45.3) | 410 (41.7) | 502 (48.7) |
| Regular low intensity | 219 (10.9) | 113 (11.5) | 106 (10.3) |
| Regular moderate intensity | 305 (15.2) | 186 (18.9) | 119 (11.6) |
| Regular high intensity | 99 (4.9) | 73 (7.4) | 26 (2.5) |
| Source of information about HTN | |||
| Internet | 344 (17.1) | 191 (19.4) | 153 (14.9) |
| From doctor or other health care professional | 576 (28.6) | 306 (31.1) | 270 (26.2) |
| Friend / Colleague | 38 (1.9) | 20 (2.0) | 18 (1.8) |
| Not interested in more information | 1093 (54.3) | 486 (49.4) | 607 (58.9) |
BP Blood Pressure, HTN Hypertension
The factors associated with HTN knowledge are outlined in Table 3. While women showed higher mean knowledge scores, sex was not significantly linked with HTN knowledge. Factors that were significantly associated with knowledge included higher level of education, higher income and presence of family history of HTN (Table 3). In addition, those who had better knowledge were more likely to check BP regularly, be aware of their blood pressure, have no/occasional alcohol consumption, frequently engage in physical activity and be a non/occasional smoker (Table 3). Additionally, knowledge scores were not significantly different between those with and without HTN.
Table 3.
Univariate analysis of factors associated with knowledge on hypertension
| Variable | All (n=2013) | Men (n=983) | Women (n=1030) | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Mean | Mean Differences (95% CI) |
p value | Mean | Mean Differences (95% CI) |
p value | Mean | Mean Differences (95% CI) |
p value | |
| Income | <0.001 | <0.001 | < 0.001 | ||||||
| < LKR 50,000 | 52.839 | -6.525 | 52.062 | -6.508 | 53.592 | -6.525 | |||
| ≥ LKR 50,000 | 59.364 | (-8.388 - -4.662) | 58.569 | (-.9.180 - -3.835) | 60.117 | (-9.125 - -3.925) | |||
| Educational Level | <0.001 | <0.001 | <0.001 | ||||||
| None/School Only | 53.647 | -6.765 | 53.432 | -4.882 | 53.872 | -8.230 | |||
| Degree or above | 60.412 | (-8.625 - -4.905) | 58.315 | (-7.607 - -2.157) | 62.102 | (-10.780 - -5.680) | |||
| Employment Status | 0.751 | 0.79 | 0.149 | ||||||
| Unemployed | 57.462 | 0.295 | 58.119 | 2.421 | 56.984 | -1.826 | |||
| Employed | 57.168 | (-1.526– 2.116) | 55.697 | (-0.284– 5.127) | 58.810 | (-4.306– 0.654) | |||
| Marital Status | 0.101 | 0.040 | 0.822 | ||||||
| Single | 58.565 | 1.709 | 58.907 | 3.155 | 58.281 | 0.320 | |||
| Married | 56.857 | (-0.332– 3.748) | 55.752 | (1.532– 6.161) | 57.962 | (-2.461– 3.101 | |||
| Diagnosed with HTN | 0.201 | 0.824 | 0.180 | ||||||
| Yes | 57.814 | 1.148 | 56.620 | 0.287 | 58.757 | 1.696 | |||
| No | 56.667 | (-0.613– 2.909) | 56.333 | (-2.242– 2.816) | 57.061 | (-0.783– 4.156) | |||
| Family History of HTN | <0.001 | <0.001 | 0.120 | ||||||
| Yes | 58.686 | -4.664 | 58.767 | -6.560 | 58.619 | -2.212 | |||
| No | 54.042 | (-6.545 - -2.743) | 52.206 | (-9.177 - -3.943) | 56.407 | (-5.003– 0.580) | |||
| Regular BP Checking | <0.001 | <0.001 | 0.007 | ||||||
| Yes | 58.311 | -5.351 | 57.697 | -7.090 | 58.926 | -4.140 | |||
| No | 52.960 | (-7.565 - -3.137) | 50.607 | (-10.402 - -3.779) | 54.786 | (-7.122 - -1.158) | |||
| Awareness of normal BP | <0.001 | <0.001 | <0.001 | ||||||
| Yes | 64.493 | -14.991 | 63.697 | -13.983 | 65.158 | -15.890 | |||
| No | 49.502 | (-16.624 - -13.359) | 49.714 | (-16.354 - -11.611) | 49.267 | (-18.153 - -13.628) | |||
| Alcohol Use | <0.001 | <0.001 | 0.382 | ||||||
| Regular | 51.292 | 6.565 | 50.352 | 7.161 | 55.134 | 3.014 | |||
| None/Occasional | 57.857 | (3.482– 9.648) | 57.512 | (3.065– 10.716) | 58.148 | (-3.743– 9.770) | |||
| Tobacco Use | <0.001 | 0.003 | 0.022 | ||||||
| Regular | 50.841 | 6.920 | 51.239 | 5.932 | 48.995 | 9.276 | |||
| None | 57.761 | (3.489– 10.352) | 57.171 | (1.987– 9.831) | 58.271 | (1.338– 17.213) | |||
| Activity Level | 0.010 | 0.085 | 0.018 | ||||||
| Inadequate | 58.996 | -2.490 | 57.891 | -2.286 | 60.634 | -3.422 | |||
| Adequate | 56.506 | (-4.389– 0.592) | 55.606 | (-4.887– 0.316) | 57.212 | (-6.267– -0.579) | |||
BP Blood Pressure, HTN Hypertension
Table 4 depicts the linear regression models consisting of significant correlates of HTN knowledge for hypertensive and normotensive individuals separately. Among respondents with HTN (n = 849), several factors were significantly associated with knowledge. The regression model for hypertensives identified higher level of income, awareness of blood pressure levels, regular blood pressure checks, family history of hypertension, normal or less salt income, none/occasional alcohol use and none/occasional tobacco use to be significantly associated with higher knowledge scores explaining 55% of the variance in knowledge score (R = 0.742 and R2 = 0.550). Amongst normotensive participants, the model identified higher level of income, family history of hypertension, higher educational level, awareness of blood pressure values, and regular blood pressure checks to be significantly associated with higher knowledge scores. Moreover, no/occasional tobacco use appeared in the final model despite not being statistically significant. The overall model was able to explain 38.3% of the variance (R = 0.619, R2 = 0.383).
Table 4.
Multivariate linear regression analysis of factors associated with knowledge about hypertension vs. normotensives
| Exp (B) | 95% CI | p-value | |
|---|---|---|---|
| Among respondents with hypertension* | |||
| Monthly income (> LKR50,000) | 3.573 | 1.702–5.445 | < 0.001 |
| Family history of HTN | 3.670 | 1.534–5.806 | < 0.001 |
| Regular alcohol consumption | −2.971 | −5.818– −0.128 | 0.041 |
| Regular BP checking | 8.090 | 2.931–13.249 | 0.002 |
| Awareness about normal BP values | 14.003 | 12.191–15.816 | < 0.001 |
| Non-smoker | 12.762 | 10.758–14.766 | < 0.001 |
| Normal Salt Intake | 15.467 | 13.305–17.630 | < 0.001 |
| Among respondents without hypertension** | |||
| Monthly income (> LKR50,000) | 3.179 | 0.082–6.277 | 0.044 |
| Higher educational level | 3.791 | 1.197–6.386 | 0.004 |
| Family history of HTN | 3.333 | 0.691–5.976 | 0.014 |
| Non-smoker | 3.879 | −0.553–8.310 | 0.086 |
| Regular BP checking | 6.002 | 2.960–9.045 | < 0.001 |
| Awareness about normal BP values | 21.515 | 18.966–24.063 | < 0.001 |
*Constant = 21.010, Nagelkerke-R2 = 0.550, p < 0.001; ** Constant = 114.249, Nagelkerke-R2 = 0.383, p < 0.001
Attitudes to and practices in hypertension
In general, respondents exhibited positive attitudes to HTN prevention and management, with 81.0% (n = 1630) understanding the significance of treatment adherence, though fewer (48.1%, n = 968) recognized the role of weight loss in preventing HTN/controlling BP (Table 2). BP checking was high among participants, with 80.7% (n = 1624) having checked their BP at least once in the past year. Only 12.8% (n = 258) reported adding extra salt to meals, and 7.0% (n = 141) smoked regularly, while 74.2% (n = 1493) abstained from alcohol consumption (Table 2).
In a binary-logistic regression analysis for regular BP checking, individuals diagnosed with hypertension were over seven times more likely to engage in this practice (OR: 7.28, 95%CI: 4.67–11.35, p < 0.001). Similarly, knowledge of stroke as a consequence of HTN (OR: 2.02, 95%CI: 1.32–3.08, p = 0.001) and having a family history of HTN (OR: 1.85, 95%CI: 1.29–2.64, p = 0.001) were positively associated with regular BP checks. Conversely, not knowing the normal BP value (OR: 0.48, 95%CI: 0.33–0.70, p < 0.001) was negatively associated. Better knowledge of consequences of HTN also increased the likelihood of regular BP checks (OR: 1.57, 95%CI: 1.05–2.35, p = 0.029). The model explained 28.8% of the variance (Nagelkerke R² = 0.288). A similar binary-logistic regression model for excessive salt consumption explained 15.3% of the variance (Nagelkerke R² = 0.153). In this model, living in an urban area was a significant positive predictor (OR: 2.21, 95%CI: 1.56–3.12, p < 0.001). However, knowledge of stroke as a consequence of HTN (OR: 0.61, 95%CI: 0.42–0.89, p = 0.01) reduced the likelihood of this practice (Table 5).
Table 5.
Factors associated with practices related to hypertension
| Exp (B) | 95% CI | p-value | |
|---|---|---|---|
| Regular blood pressure (BP) checkinga | |||
| Lives outside the Colombo district | 1.58 | 1.08–2.64 | 0.017 |
| Unmarried | 0.48 | 0.33–0.70 | < 0.001 |
| Knows the normal BP value | 2.01 | 1.39–2.91 | < 0.001 |
| Knowledge of HTN consequences | 1.57 | 1.05–2.35 | 0.029 |
| Knowledge of stroke as a consequence | 2.02 | 1.32–3.08 | 0.001 |
| Family history of HTN | 1.85 | 1.29–2.64 | 0.001 |
| Does not acknowledge HTN as a condition requiring long-term treatment | 0.51 | 0.32–0.82 | 0.006 |
| Diagnosed with HTN | 7.28 | 4.67–11.35 | < 0.001 |
| Excessive salt consumptionb | |||
| Women | 0.71 | 0.51–0.98 | 0.039 |
| Living in an urban area | 2.21 | 1.56–3.12 | < 0.001 |
| Knowledge of stroke as a consequence | 0.61 | 0.42–0.89 | 0.01 |
| Does not acknowledge HTN as a condition | 2.33 | 1.48–3.68 | < 0.001 |
| Education level (Diploma/degree) | 1.63 | 1.16–2.30 | 0.005 |
| Interested in further information on HTN | 0.54 | 0.38–0.75 | < 0.001 |
BP Blood Pressure, HTN Hypertension
aConstant = −0.129, Nagelkerke-R2 = 0.288
bConstant= − 1.578, Nagelkerke-R2 = 0.153
Discussion
HTN is an important public health challenge, especially in low- and middle-income countries like Sri Lanka [5], where genetic predisposition in combination with lifestyle factors, socioeconomic disparities [18], and suboptimal health literacy are likely to exacerbate its prevalence and outcomes. This KAP survey provides valuable insights related to HTN in a large cohort representative of the Sri Lankan population, shedding light on critical gaps and opportunities for intervention. The findings underscore the complex interplay of socioeconomic, educational, and behavioural factors in influencing health outcomes and provide a foundation for targeted public health strategies. The study population closely reflects the socio-demographic characteristics of the general Sri Lankan population, with the gender distribution being nearly equal (men: 48.8%, women: 51.2%), consistent with national statistics [19].
Our results show a mean knowledge score of 57.3±20.1% (range: −5.2 to 100.0), being not significantly different between those with and without HTN, with a significant proportion demonstrating a knowledge score < 50.0% (36.3% of all respondents and 36.8% of people with HTN), despite Sri Lanka’s high general literacy rate. This finding aligns with evidence suggesting that general literacy does not necessarily translate to health literacy [20], an important factor particularly in the management of chronic conditions like HTN [21]. While no completely relatable literature was identified, given the differences in questionnaires used, a limited number of KAP studies on hypertension in Sri Lanka are available. Most existing studies, such as those by Pirasath et al. [22, 23], and Ralapanawa et al. [24] were conducted in hospital-based populations and demonstrated relatively higher knowledge levels. Similar findings have also been observed in regional countries like India [25] and Pakistan [26]. This is consistent with our interpretation that patients receiving care in tertiary settings benefit from structured health education. In contrast, our online survey, which reached a broader and more diverse demographic, including normotensive individuals, demonstrates lower knowledge scores, possibly reflecting community-wide gaps in health literacy. The significant percentage of participants with a low knowledge score among those with HTN implies a lack of understanding of the disease, its risks, and the importance of treatment adherence. This can lead to uncontrolled BP, increased risk of complications, and poor self-care practices. Furthermore, it also reflects broader systemic issues, including failures in the healthcare system and deficiencies in education. Healthcare providers may not be communicating critical information in a way that people can understand or act upon, highlighting gaps in counselling and community outreach [27].
We also identified key knowledge gaps in the present study population, including poor knowledge about risk factors, both in people with and without HTN. Also, knowledge of consequences like eye disease (30.8%) and kidney disease (39.1%) was poor in both groups. This is important in the background where hypertension together with diabetes is the leading cause of chronic kidney disease in the Sri Lanka population [28]. However, the high awareness of heart disease (87.4%) and stroke (76.4%) as consequences of uncontrolled HTN suggests that public health campaigns have been somewhat effective in highlighting severe cardiovascular risks but have not sufficiently addressed less overt complications. In contrast, we also identified the presence of misconceptions in the study population. For example, misconceptions about water intake and its role in HTN was a notable finding. In a country where complementary and alternative medicine use is common for chronic non-communicable conditions such as HTN, where traditional medicinal practices are not as stringently regulated [29], and where the health literacy of the population is low [15], misconceptions regarding a condition, its risk factors, consequences and management raise significant concerns. This highlights the urgent need for targeted health education initiatives to dispel such myths and promote evidence-based practices in HTN management. Similar findings have been observed in other developing counties; for example a qualitative study in Ghana revealed several unscientific misconceptions and beliefs about hypertension, which could influence their disease management and control decisions [30]. Another study in Kenya identified that 21% of respondents were of the opinion that they will achieve a permanent cure only from alternative medical practitioners and will consider using alternative medicine in future for hypertension [31]. These consistent findings across countries with similar socio-economic backgrounds point to systemic gaps in community health education that transcend healthcare systems or geographies.
The study finding that individuals, including those with HTN, had poor knowledge about BP values, highlights a significant barrier to effective HTN management. This lack of awareness can result in inadequate self-monitoring, poor risk perception, and reduced adherence to treatment regimens. Sufficient knowledge about BP targets is important to empower individuals to take proactive steps in managing HTN. Individuals who understand their target BP values are more likely to adhere to medication and make necessary lifestyle changes, resulting in better BP control and long-term outcomes [32]. Therefore, addressing this knowledge gap through targeted educational programmes, patient-provider communication, and digital tools could substantially improve HTN control and reduce the risk of complications such as stroke. Our analysis also revealed that higher levels of education were a significant determinant of better knowledge. Respondents with higher levels of education were more likely to demonstrate better levels of knowledge and vice versa. Added to that is the higher knowledge scores association with increased level of income. These findings reflect the critical role of socioeconomic status in shaping health literacy and access to information. Studies have shown individuals with lower socio-economic status exhibit reduced health literacy, which can adversely affect their health behaviours and disease outcomes [33]. Low health literacy in those with lower socioeconomic status has been shown to be associated with inadequate BP control [34]. We also identified that urban residents had higher knowledge levels than their rural counterparts. Previous studies in other countries have also revealed that urban adults had higher rates of HTN awareness and treatment than their rural counterparts, attributed to better healthcare infrastructure and educational resources in urban area [35]. These findings highlight the necessity for tailored public health strategies to improve HTN knowledge in populations with poor socio-economic status and in rural communities, thereby reducing health inequities that exist between these populations.
Attitudes to HTN can significantly influence behaviours related to its prevention and management [36]. Previous studies have shown that individuals who believed they had control over their health outcomes were more likely to engage in preventative behaviours in relation to HTN [37]. In the present cohort attitudes toward HTN management varied, with positive attitudes towards the importance of treatment adherence (81.0%) and regular BP monitoring (80.7%). Also, behavioural and attitudinal barriers, such as not acknowledging HTN as a chronic condition requiring treatment, were significant negative predictors of health practices, such as lower BP monitoring rates and higher salt consumption. In addition, our results highlight a likely interplay between attitudes and knowledge. Among people with HTN, respondents with better knowledge were more likely to exhibit positive attitudes toward treatment adherence and among individuals without HTN those with better knowledge were more likely to have a positive attitude towards weight loss. Therefore, integrating knowledge enhancement into attitude-focused interventions would be important to ensure sustainable behavioural change.
The study revealed that regular BP monitoring and having a family history of HTN were significantly associated with knowledge of HTN, especially its consequences such as stroke. Among hypertensive respondents, those diagnosed with HTN were over seven times more likely to monitor their BP regularly. This finding highlights the impact of personal and familial experience with the condition in driving proactive health practices. The study highlights several behavioural barriers to effective HTN management, including misconceptions about HTN as a chronic condition and poor attitudes toward key modifiable factors like weight loss and salt reduction. Addressing these barriers requires a multifaceted approach that combines education, community engagement, and policy-level interventions. For example, integrating HTN education into existing healthcare delivery frameworks, such as primary care visits and community health programmes, could enhance awareness and foster positive attitudes. Digital health tools, such as mobile apps tailored to the Sri Lankan population, could play a pivotal role in bridging the knowledge gap. These tools could provide accessible, culturally relevant information on HTN prevention and management, enabling individuals to make informed health decisions.
This study is one of the few large-scale surveys on HTN knowledge, attitudes and practices in Sri Lanka, leveraging an online platform to reach a diverse population. The robust sample size (n = 2013) enhances the generalisability of the findings. However, several limitations are noted. The reliance on self-reported data may introduce reporting bias. Another key limitation of this study is the potential selection bias introduced by the online survey methodology, which may have disproportionately reached individuals with better socioeconomic status and higher digital literacy. Since the survey was disseminated via social media platforms and professional networks, individuals from lower-income or digitally disadvantaged backgrounds may have been underrepresented. To mitigate this bias, we employed multiple strategies, including targeting diverse social media groups beyond professional circles and encouraging participants to share the survey within their own networks. Despite these efforts, and the ways in which our subjects were representative (including gender, urban-rural and geographical distribution), the possibility of overrepresentation of certain socioeconomic groups remains, which should be considered when interpreting the findings. In addition, although disseminated widely via social media across Sri Lanka, we used a non-probabilistic convenience sampling method and thus the study cannot be considered nationally representative. While participants were from all provinces, certain socioeconomic groups may be overrepresented due to the online nature of the survey. Future studies could also employ mixed-method approaches, such as incorporating offline recruitment strategies with focus group discussions and in-depth interviews, to improve representativeness. Furthermore, information on the place of follow-up for hypertension (e.g., primary or tertiary care) and prior hospital admissions related to hypertension-related complications such as stroke were not collected in this study. Therefore, we were unable to analyse how these factors may have influenced or correlated with participants. We recommend future studies consider incorporating clinical follow-up data to better contextualize knowledge levels with real-world healthcare interactions and outcomes. Another limitation is that alcohol consumption was assessed solely based on volume (mL/day) without accounting for the type of alcoholic beverage consumed. While different types of alcohol vary in ethanol concentration, potentially leading to variability in actual intake, this approach was considered the most reasonable for the Sri Lankan population, where standard alcohol units may not be well understood.
Conclusions
This study highlights critical gaps in the knowledge, attitude and practices related to HTN among Sri Lankans, driven by socioeconomic, educational, and behavioural factors. The findings underscore the need for targeted public health interventions to address knowledge gaps and behavioural barriers to HTN management. Addressing misconceptions and emphasizing modifiable risk factors are important. In addition, there is a need to expand health education and healthcare services to rural communities and those with poor socioeconomic status to address disparities in knowledge and practices. Furthermore, integrating health literacy programmes into national health strategies will be crucial to ensure sustainable improvements in HTN management outcomes.
Supplementary Information
Acknowledgements
None.
Previous presentations
None.
Authors’ contributions
PR, PW, MM, SL, TP, MS and DJW conceptualized and designed the research. PR, PW, MM, and DJW drafted the manuscript. All authors reviewed and approved the final version of the manuscript.
Funding
None.
Data availability
Data can be provided upon a reasonable request from the corresponding author.
Declarations
Ethics approval and consent to participate
Ethical approval for the study was obtained from the Ethics Review Committee, Faculty of Medicine, University of Colombo (EC-23-047). Consent was obtained prior to survey completion. The study adhered to the Declaration of Helsinki.
Consent for publication
All authors unanimously provide consent for publication.
Competing interests
The authors declare no competing interests.
Footnotes
Publisher’s Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
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Data Availability Statement
Data can be provided upon a reasonable request from the corresponding author.