Awareness, treatment, control of hypertension and utilization of health care services following screening in the North-central region of Burkina Faso

Introduction In Africa, a non-urban area is affected by hypertension. But in Burkina Faso, no study on factors associated with awareness, treatment and control of hypertension has not yet been published. The objectives of this report are to: (i) identify the factors associated with awareness, treatment, and control of hypertension in the adult population of Kaya health and demographic surveillance system (Kaya HDSS) and (ii) estimate health care services utilization by participant newly screened as hypertensive. Methods A screening survey for hypertension was conducted on 1481 adults in Kaya HDSS in late 2012. Hypertensive individuals provided information relating to “awareness”, “treatment” and “control” of their hypertension. After approximately two months, unaware hypertensive individuals were interviewed to know whether they had sought treatment. Results During the screening survey, 123 individuals (9.4%) were identified as having hypertension. Among them, 33 (26.8%, 95% CI: 18.9-34.8) were aware of their condition, 25 (75.8%, 95% CI: 60.3-91.2) of them were receiving medication. Among those receiving treatment, 15 (60.0%, 95% CI: 39.4-80.6) had their blood pressure controlled. Semi-urban residence, presence of chronic diseases and physical inactivity were significantly associated with awareness of hypertension. Seventy two of the 90 participants who were classified as unaware were interviewed two months later. Out of them, 37 individuals had consulted a health worker and 28 received a diagnosis of hypertension. Conclusion Awareness was low but treatment and control of those who knew they were hypertensive were relatively high. These results could be used to improve management of hypertension in Burkina Faso.


Introduction
Of the 57 million estimated deaths in 2008, cardiovascular diseases were responsible for 17 million deaths, of these, 80% occurred in low and middle-income countries [1]. Hypertension is recognized as a major risk factor of cardiovascular disease [2]. In 2010 it was identified as the primary risk factor for global burden of disease, with 7% of global disability-adjusted life years (DALYs) [3]. Nearly a quarter of the world´s adult population had hypertension in 2000 and an increase of 60% was forecast for 2025. At the same time, in sub-Saharan Africa (SSA) a faster increase was projected [4]. This increasing trend was confirmed by another study, estimating 75 million people with hypertension in SSA in 2008 and 125 million in 2025 [5].
In addition to this projected increase, levels of awareness, treatment and control of hypertension are low in Africa countries.
Prevalence in urban areas of Burkina Faso has been estimated to be over 20% [11,12]. We have recently reported a prevalence of 9.4% in the rural and semi-urban areas of Kaya health and demographic surveillance system (Kaya HDSS) [13]. However, estimates of awareness, treatment and control of hypertension are not yet available. Thus, we conducted this investigation to: (i) identify the factors associated with awareness, treatment, and control of hypertension in the adult population of the rural and semi-urban area of the Kaya HDSS; and (ii) estimate health care services utilization by participant newly screened as hypertensive. We anticipate that information from this two-stage study would contribute to strengthen the detection and control of this impending epidemic of hypertension in developing countries. More detailed description of the site was described elsewhere [14].

Methods
The list of households at the Kaya HDSS provided a sampling frame for a rural and a semi-urban stratum. In each household, one adult (aged 18 years and over) was randomly selected and invited to participate.
Information on sex, age, place of residence, marital status, education, and occupation were gathered. Relevant behavioral pattern were queried using the World Health Organization stepwise approach to chronic disease risk factor surveillance (STEPS) instrument for non-communicable disease risk factors [15]. The question "Do you currently smoke tobacco products such as cigarettes, cigars or pipe" was asked. When the answer was negative, a second question "In the past, did you smoke daily" was asked to identify ex-smokers. Smokers and ex-smokers were combined into one group because number of ex-smokers was small.
For alcohol, the question "Have you ever consumed alcoholic beverages such as beer, wine, liquor, local beer" was asked. For physical activities, the participants were asked whether they had intensive activities (activities that required a substantial increase in breathing or heart rate for at least 10 minutes) or moderate activities (activity that required moderate increase in breathing or heart rate for at least 10 minutes) in their current occupation.
Further, the participants were asked whether they took part in other strenuous activities or moderate activities in their leisure time.
Participants who had strenuous or moderate activities were classified as "having vigorous physical activity"; otherwise as "having non-vigorous physical activity".
For chronic conditions, the participants were asked whether they had ever been informed by a health professional that they had a chronic disease such as diabetes mellitus, cancer, AIDS, heart problems, or asthma. Family history of hypertension was assessed by asking the participants whether one of their relatives including grandparents, father, mother, brother or sister had hypertension.
The experience of Blood Pressure (BP) measurement was assessed by asking the question "Is a doctor or health worker has already measured your BP" In case of an affirmative answer, a second question" When was the last measure of your blood pressure" was asked. Weight was measured using a digital scale, with participants lightly dressed and after removal of shoes and pocket contents.
Height was measured with participants in standing position without shoes, using a wooden stadiometer. BMI was computed by dividing the weight (kg) with the square of the height (m 2 ) and participants Page number not for citation purposes 3 were considered "underweight" when their BMI is below 18.5; "normal weight" when BMI is above or equal to 18.5 and below 25; "overweight" when BMI is above or equal 25 and below 30; and "obese" when BMI is above or equal to 30 [16].
Blood pressure (BP) was measured on one occasion at home by were asked to show their drug boxes to the interviewer and drugs were recorded. Control: a treated hypertensive individuals who had a systolic blood pressure < 140 mm Hg and diastolic blood pressure < 90 mm Hg was considered having the hypertension "controlled".
Non-pharmacological treatments were defined as behavioral advice received from a health care professional for management of hypertension [18]. Participants were asked if they received advice to reduce salt consumption, weight loss, smoking cessation and to reduce alcohol consumption as well as to increase physical activities.
Use of traditional medicine to treat hypertension also was ascertained.

Second stage, follow up interviews
Participants of the follow up interview were hypertensive individuals who were unaware of their hypertension in the first stage. They were advised to seek professional health care for further hypertensive management. After approximately six weeks to two months, interviewers returned to the home of this new hypertensive and conducted an interview using a structured questionnaire.
Participants were asked if they had since seen a health professional.
If not, they were asked about the reasons for not doing so. If they had done so, they were asked about the frequency they had blood pressure taken and if hypertension was confirmed, the prescribed

Statistical analysis
Proportions of hypertensive participants who were aware of their status, were receiving pharmacological treatment and whose hypertension was controlled were calculated. Chi-square tests were used to compare the proportions of hypertensive participants who were aware of their condition by selected characteristics. Logistic regression analyses were used to compute odds ratios with 95% confidence intervals for selected factors potentially associated with awareness. A significance level of P < .05 was used. For the followup study, proportions of people with confirmed diagnosis and prescribed antihypertensive medication were estimated. All statistical analyses were performed using IBM SPSS 20 for Windows.

Ethics
The study was approved by the Ethics Committee of Health

Research at the University of Montreal in Canada and the Ethics
Committee on Health Research in Burkina Faso. All participants were free to participate and a written informed consent was obtained.

Results
As the first stage survey, 1481 participants have been screened. were not. Figure 1 shows the proportion of hypertensive received medication prescription (Figure 2).

Discussion
Our results show that in the North-Central region of Burkina Faso, BP measuring was not common. The proportion of adults who had never measured their BP (2 out of 5 adults) is high and comparable to that found among adults (54%) in Northern Angola [9].
Ignorance of the population and inaccessibility of health services could explain that situation and one of its consequences will be a low awareness of hypertension. Accordingly, in this region of Burkina Faso, awareness of hypertension was low and comparable to some countries in West Africa [19] and elsewhere in African countries [9,20]. Awareness hardly exceeds 40% in sub-Saharan Africa [6,10]. In developed countries, detection is higher; on the average 49% for men and 62% for women [21].
The low awareness in African countries results from a combination of lack of knowledge about hypertension, lack of availability of primary care and missed opportunities for diagnosis in primary care [22,23]. In this study only 37% of our participants had knowledge about hypertension, similar levels of ignorance were reported in Ouagadougou [11] and Nigeria [23]. Lack of primary health care including blood pressure screening has been found elsewhere in Africa [9]. Because hypertension is mostly asymptomatic, it is usually not detected without actively seeking attention.  [8,19]. This is probably due to better equipment and better access to health services in semi-urban areas compared to rural areas.  [7]. Result of treatment of other studies were between 13.9% and 52% of those who were aware [8,9,19,20]. In our study, the fact that 75% of those who were aware were on treatment could be explained by their additionally poor health status. The proportion of aware hypertensive that was not on drug treatment was rather significant (25%). The proportion of treated hypertensive patients with controlled blood pressure in this study was higher (60%) than that found in other African countries [6,25,26].
Calcium channel blocker (CCB) was the most widely used anti hypertension medicine in monotherapy as found in Cote d'Ivoire [27]. This was in line with European society of hypertension and The follow-up results showed a low utilization of health care.
Despite our advice, nearly half did not seek medical attention. This low attendance of health facilities has been previously recognized in Tanzania [22]. It could indicate ignorance or more likely, a lack of resources. In Burkina Faso, public health insurance is not available and patients must pay for care out of their pockets. Lack of transportation and time because of work and home duties may also discourage people from obtaining further medical attention.

Strengths and limitations
To our knowledge, a study on the awareness, treatment and control has not yet been published on the semi-urban and rural population of Burkina Faso; the present study is the first of its kind and results are based on a randomly selected sample which was representative of the population. Also this is the first study that shows the results of follow up of newly screened hypertensive in West Africa. This study has limitations. The sample size is small and we had insufficient statistical power to analyze factors associated with treatment and control among those who were aware of their condition.

Conclusion
In