Hypertension is one of the most significant modifiable risk factors for cardiovascular diseases (CVDs) worldwide [1], with increasing pervasiveness in low- and middle-income countries [2]. Currently, high blood pressure (BP) has been reported to cause 7.5 million deaths, which account for approximately 12.8% of the total deaths occurring globally [3]. Of these CVD deaths, 53% are due to complications of hypertension. High BP is called the “silent killer” because often, it has no warning symptoms or signs, and many people do not know that they have it [4]. Factors attributed to the increased prevalence of hypertension include population growth; aging population; and behavioral risk factors such as smoking, low-quality diet, harmful alcohol consumption, less physical activity, and overweight or obesity [5].

A review of community-based interventions for CVD implemented in low- and middle-income countries recommends that patient education can have a positive effect on treatment adherence and BP control among individuals with hypertension [6]. The literature provides ample information on health education programs to support self-management for individuals with hypertension living in high-income countries [7]. However, information on the impact of the best possible education programs for individual with hypertension in low-resource countries is not available [8]. To fill the gap, in this study, we provide periodic health education aimed at increasing awareness on the relationship between BP level and salt intake, and knowledge about behavioral changes related to hypertension for positively influencing patients’ perceptions of hypertension and their adherence to treatment remedies [9].

However, the current status of the knowledge, attitudes, and perceptions of hypertension among participants indicates the significance of awareness buildup with respect to various features of hypertension, basic changes in lifestyle, and detailing of procedures in improving health education. Moreover, participants’ knowledge about hypertension and the benefits of lifestyle modifications by all means is important for successful management of hypertension [10]. Nevertheless, lifestyle changes are not effectively accomplished. Hence, a combination of health education, knowledge of behavioral changes, and periodic use of mobile health (mHealth) technology could be provided in a patient-centered manner [11], as adherence to treatment is likely to increase when participants have positive attitudes toward controlling hypertension. Subsequently, well-structured educational interventions along with active participation of the patients are vital to increasing the knowledge, self-monitoring, and control of hypertension.

To expand awareness of the target population, innovative techniques are introduced in this study. One is regular BP checkup by the use of a Portable Health Clinic system (developed by Kyushu University, Japan, and Grameen Communications, Bangladesh) during home visits by community health workers (CHWs), in light of the fact that a routine health checkup system at the community level is yet to be established in Bangladesh, particularly in its rural areas. For example, medical personnel such as community nurses, during their field visits, may routinely check the BP of hypertensive individuals, who do not have any BP self-checking facility at home.

The second extraordinary contraptions are used to measure food and urine salinity to alert the participants. The third strategy is the persuasive motivating approach and social capacity building using mHealth technology for behavioral change.

We hypothesize that awareness development and knowledge acquisition can enhance behavioral change, and periodical mobile phone–based SMS intervention will be significantly beneficial in modifying lifestyle changes among hypertensive individuals. Thus, this approach could minimize the hypertension status of participants as well as its complications.

The objectives of this study are to develop awareness and enhance knowledge through health education, the use of mHealth technology, and change in lifestyle behaviors among hypertensive individuals in a rural community of Bangladesh.

This is a single-center, randomized (1:1), open-label, parallel-group study, conducted in a rural community of Mirzapur, Bangladesh. The intervention period was 5 months for each individual, and the total study duration was 12 months.

Individuals with hypertension living in the study site were identified as follows. One group of individuals were identified from a tertiary-level health facility (Kumudini Hospital, Mirzapur, Bangladesh). The principal investigator and CHWs visited the tertiary facility and checked the database records as well as the registered notebook including current remedies from the facility and collected household contact information (ie, home address and phone number) with the permission of the hospital authorities. Afterwards, CHWs visited homes of the participants and obtained their consent to participate in this study. The other group of individuals were identified from the neighborhood rural communities arbitrarily by CHWs reviewing the registered clinician’s prescriptions and current remedies by household visits, and obtained their consent for the study.

A purposive sampling method was followed for enrolling study participants who met the eligibility criteria and were willing to participate voluntarily in the study.

Participants who met the following criteria were eligible for enrollment into the study:

Individuals of either sex who have hypertension and are aged 35 years or above, have 1-5 years of schooling, reside within a radius of 3 miles from the Kumudini Women’s Medical College and Hospital, are likely to stay in the community for the ensuing 5 months, have a personal cell phone or access to a shared phone, are open and can exchange their views freely, are willing to participate in the study, and consented to comply with the health education and periodic text messages for the entire study period.

Individuals with mental illnesses or serious comorbidities such as progressive diabetes, chronic pulmonary disease, malignancy, and pulmonary tuberculosis that might cause periodic absence were excluded from this study.

A randomization schedule was prepared following the permuted block randomization technique using a block size of 4 based on a computer-generated series of numbers. An experienced researcher (third party) who was not involved with the study generated the random allocation by sequence and distributed that in serially numbered sealed opaque envelopes, which are kept in locked file cabinets in a site away from the trial’s location. Sealed envelopes containing group assignment were given to the eight CHWs who were involved in participants’ enrollment under the guidance of a principal investigator.

Enrollment took place during morning hours for 6 consecutive days (except Friday) in a week, and the principal investigator of the study was present at the site every day to ensure compliance with the study protocol. Once eligibility for randomization was determined, written informed consent was obtained. CHWs opened the envelope in the presence of participants. Participants were allocated to either of the groups, after enrollment, CHWs collected their demographic information and performed physical examination of the participants.

Sample size calculation was based on the behavioral changes of study participants. In this study, investigators compared two interventions (health education with and without text messaging). Investigators expected the compliance of the intervention group to be higher than that of the control group. We assumed that the proportion of patients in compliance is at most 10%-12% better in health education with text messaging group.

The sample size was calculated with a two-tailed 5% significance level and a power of 80%, with a 95% CI (1–α) to detect varying differences in the effectiveness of the two intervention groups. Adherence rates were assumed to differ by 10%-12%, that is, rates of 90% in the study group and 78%-80% in the control group, with a presumption that 6% of the participants would be lost during the follow-up (for example, if the intervention group adherence rate is 10% higher than that of the control group, then the difference will be 90%–80%=10%; if the intervention group adherence rate is 11% higher than that of the control group, then the difference will be 90%–79%=11%). The sample size for each group was estimated to be between 153 and 210 participants. Thus, considering the largest calculated sample size, the study finally had a sample size of 210 in each group.

Once the participants were made aware of the importance of lifestyle changes and obtained knowledge about lifestyle modification, they could change their lifestyles. Thus, increased awareness and knowledge was measured by the actual behavior change in them. Following the lifestyle change, their BP level was expected to decrease, the risk for complications would be reduced, and their quality of life would be improved. Therefore, we set the following end points.

As a secondary outcome, the feasibility of utilizing mobile phones in hypertensive individuals using field-testing questionnaires was checked by the researcher-developed questionnaire.

Researchers have strongly recommended economic evaluation of health promotion interventions such as health education and mHealth technology [13]. For this purpose, all costs were classified according to major activities or resources. Costs were derived from two phases of the intervention named start-up costs and implementation costs, which are directly related to the study. Total costs were considered as the summation of capital and recurrent cost items for each phase [14].

At baseline, a standardized pretested questionnaire was administered to obtain information on the sociodemographic profile such as age; gender; religion; financial dependency; educational qualification; occupation; monthly family income and expense; type of housing; possessions of household land and properties; type of family; marital status of the respondent; living arrangements; health status; health care–seeking behavior; family history; hypertension-related information; hospitalization history; food consumption practices; lifestyle behavior such as tobacco use; alcohol consumption; food habits; the level of physical activity; and mHealth-relevant information.

Nutritional status assessments such as height, weight, mid-upper arm circumference, hip circumference, and waist circumference were measured by CHWs. BP, random blood sugar, urinary protein and glucose, and salinity of food and urine were measured using the standard procedure starting from the enrollment day till the end of the follow-up. Follow-up visits and physical examinations were performed at households, at Kumudini Hospital, or in the nearest HFWC.

All participants were explicitly informed about the objectives, importance, and risks and benefits of the research before recruitment. Participation was completely voluntary, and written informed consent was obtained from all participants.

This study was approved by the Bangladesh Medical Research Council (BMRC; Registration No. 06025072017), with Clinical Trial Registration No. NCT03614104 and UMIN Registration No. R000033736. This study was conducted in accordance with the Declaration of Helsinki and the Ethical Guidelines for Clinical Studies of the Ministry of Health, Labor and Welfare of Japan. Enrollment of participants started in August 2018, and collection of follow-up data was completed at the end of July 2019.

In 5% of the study participants, the quality control team independently checked data collected on the same day using a field-tested methodology. Errors detected were corrected immediately at the field site. Later on, scoring was completed for each question of the repeated interview (eg, 1=same, 2=different but possible, 3=different and not possible, 4=impossible to judge, and 0=not applicable). The sum of all the scores was divided by the total number of questions/variables asked. The ideal score was 1 or a score as close to 1 as possible. If the score exceeded 1.5, the CHW responsible for the interview was questioned regarding the differences. The findings of the quality control team were considered for necessary corrections if any major discrepancies were found.

The intend-to-treat analysis was used to compare the outcomes of the intervention and control groups. To ensure comparability of randomized samples, all baseline indicators at the time of registration were analyzed. The data will be expressed as the mean±standard deviation or median (minimum-maximum) and cross tabulation (with the range or percentage with 95% CI where appropriate) for continuous variables and as frequencies and percentages for discrete variables. The differences in continuous variables between the groups were examined using the t-test or Mann-Whitney U test. The differences in categorical variables between groups were examined using χ² test. For primary and secondary endpoint analyses, Mann-Whitney U test was performed to assess the changes in health behaviors at baseline, and analysis of covariate was performed to assess the changes in health behaviors at baseline and 5 months after the follow-up. Analysis of covariance was used to check the correlation between a dependent variable and the covariate independent variables and to remove the variability from the dependent variable that can be accounted for by the covariates. A multivariate regression analysis was then performed to evaluate the simultaneous effects of various exposure variables after adjusting for any confounding variables. Data were analyzed using the statistical software packages SPSS for Windows version 25.0 (IBM Corp) and Epi Info version 7.0 (Centers for Disease Control and Prevention). Values of P<.05 are considered statistically significant.

This paper describes the protocol for a randomized control trial that aims to develop awareness, enhance knowledge, and make behavioral changes using health education and mHealth technology among individuals with hypertension in a rural community of Bangladesh. To our knowledge, this is the first study conducted in Bangladesh to measure the impacts of mobile phone SMS as a tool for reducing the burden of hypertension. One of the most significant barriers to effective treatment of hypertension is the lack of awareness and education about hypertension, its complications, and the optimal way to treat hypertension, which can be addressed by mobile phone interventions for knowledge generation as well as awareness and behavior change communications.

In this study, we sent SMSs to participants through mobile phones (two-way communication). As the SMS is written in Bengali using Bangla alphabets, we assume that it will not be very difficult for the participants to read and understand, as the ability to read the SMS messages has been considered in the inclusion criteria. Using SMS as a tool for health education, health information and lifestyle messages can be easily disseminated by persons with minimum technical knowledge and skills.

Moreover, in our study, we have used the following three unique devices to improve the self-management skills of individuals with hypertension.

Because of purposive sampling, this study does not represent hypertensive individuals of a rural community as a whole. To check the feasibility and reliability of urine and food salinity results, it is better to compare them with laboratory data, which cannot be evaluated in this study. CHWs were consented not to share the random allocation status of hypertensive individuals with the family members as well as their neighbors during the study period. However, chances of disclosure, although small, cannot be ruled out. Moreover, data contamination due to neighborhood as well as family members and obtaining consent from CHWs to not disclose the data may be other limitations of the study.

This study was conducted in rural Mirzapur, Bangladesh. This study aimed to determine the effectiveness of SMS-based interventions for health promotion and to determine whether it will be well accepted by beneficiaries. The results of the study indicated that SMS is an effective method for building awareness toward the prevention and control of hypertension and its consequences in a rural population of Bangladesh [21-23].