Diagnosis and Evaluation of Hypertension Control in Dakar: Role of Ambulatory Blood Pressure Measurement Volume 2 - Issue 5

Fatou Aw Leye ¹*, Bodian M¹, Akanni S¹, Bathily C Sarr SA¹, Mingou JS¹, Affangla A⁴, Diouf MT¹, Ndiaye M Diop CMBM¹, Ndiaye PN¹, Balde DW¹, Ngaïdé AA², Dioum M³, Leye M⁴, Ndiaye M B¹, Mbaye A³, Kane Ad⁵, Kane A⁶, Diao M¹ and Serigne Abdou BA¹

• ¹Cardiology Department, Teaching Hospital Aristide Le Dantec, Senegal
• ²Cardiology Department, General Hospital of Grand Yoff, Senegal
• ³Cardiology Department, National Teaching Hospital of Fann, Senegal
• ⁴Training and research unit of Thies, Sénégal
• ⁵Cardiology Department of regional hospital of Saint Louis, Senegal
• ⁶Cardiology Department of Dalal Jamm hospital, Dakar Senegal

Received: January 16, 2020;   Published: January 24, 2020

Corresponding author: Fatou Aw Leye, Cardiology service of the Aristide Le Dantec University Hospital Center, PO Box 6003 Dakar Etoile, Senegal

DOI: 10.32474/ACR.2020.02.000148

 

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Abstract

Introduction: Hypertension is a major public health problem in Sub-Saharan Africa. Current recommendations place particular emphasis on ambulatory measures compared to clinical ones for the diagnosis and monitoring of treated hypertensive patients. This is how we conducted this study which aims to assess the contribution of ambulatory blood pressure measurement (ABPM) in our practice.

Materials and methods: This was a descriptive cross-sectional study carried out at the cardiology department of the Aristide Le Dantec teaching hospital over a period of twelve (12) months (January 1, to December 31, 2018).

Results: We collected 122 patients during the study period, with a female predominance (M / F sex ratio = 0.69). The average age of the population was 53.22 ± 13.19 years.

The indication for ABPM was a therapeutic evaluation in 81 patients (66.40%), with a diagnostic aim of hypertension for 41 patients (33.60%) including 5 cases of Pregnancy-induced hypertension. ABPMs were normal in 30% of cases. The nycthemeral average was 140 ± 18.66 for systolic blood pressure and 84.02 ± 14.56 for diastolic blood pressure. Among the abnormal measures, we noted 45.90% of dipper subjects, and 41% of non-dippers. In the therapeutic evaluation, hypertension was controlled in 22 patients (27.2%) and uncontrolled in 59 cases (72.80%). In the diagnostic indication, hypertension was confirmed in 23 cases (63.9%) and a white coat hypertension was found in 13 cases (36.1%). Pregnancy-induced hypertension was confirmed in 3 out of 5 patients (60%).

Conclusion: This study showed the importance of ABPM as a diagnostic and therapeutic evaluation tool. Its rational use in our context would improve the care of hypertensive patients and thus prevent damage to target organs.

Keywords: Hypertension; ABPM; blood pressure control

Introduction

Hypertension is a common chronic disease representing a major public health problem. In 2000, it reached one out of four adults worldwide, ie a rate of 26.5%, with an evolution in prevalence which should reach 29% in 2025 [1]. In Africa, more than 40% of the adult population is affected, and this prevalence varies according to the country [2]. In Senegal, it affects one out of three Senegalese, ie 3 million Senegalese [3], with an estimated prevalence of 29% in people aged 18 to 69 years [4]. However, despite the seriousness of hypertension, correct treatment and good control of blood pressure figures significantly reduce the risk of cardiovascular complications. Compared to the blood pressure measurement at the medical office, the ambulatory blood pressure measurement for 24 hours reflects more accurately the patient’s blood pressure to which he is subjected in his real life conditions [5]. This examination is more correlated with the evaluation of the cardiovascular risk and the damage to the target organs than the clinical measurement and makes it possible to find certain phenomena such as hypertension called “white coat”, masked hypertension or anomalies of the circadian rhythm of blood pressure (BP). We therefore carried out a study, whose aim was to assess the contribution of ABPM in the diagnosis and evaluation of the level of control of hypertension, in the cardiology department of Aristide le Dantec Hospital.

Patients and Methods

We carried out a cross-sectional, descriptive study with data collection carried out over 12 months (January 1 to December 31, 2018) in the cardiology department of Aristide Le Dantec Hospital in Dakar. This study included all patients who benefited from an ABPM in the department, in the context of suspected hypertension or a therapeutic evaluation, and who consented to participate in the study. Invalid ABPMs (lasting less than 24 hours or less than 50 good measurements) were not included. The ABPMs were performed using a Meditech ABPM-05 brand device. Data collection and processing was carried out using HM5 software. Concerning the interpretation of the ABPM results, the reference values used are those of the meta-analysis by Staessen [6]:

a. A BP of more than 135/85 mmHg was considered as the limen for confirming the diagnosis of hypertension, for the daytime averages.

b. Hypertension was considered to be controlled for a BP <130/80 mm Hg over the entire 24-hour average.

We studied the type of systolic, diastolic or systolo-diastolic hypertension. We analyzed the nycthemeral profile for: diurnal, nocturnal or both. Finally, we looked for the existence of a night dip. Were classically defined as ‘non-dippers’, patients who did not show a decrease in day and night blood pressure of at least 10/5 mmHg or at least 10% [7]. In contrast, subjects with nighttime BP drop values greater than 20% can be considered « extreme dippers » [8].

Patients were said to be “dippers” when their nocturnal BP decreased by 10 to 20%. A lowering of more than 20% defined extreme dipper patients. Non-dipper patients had a decrease of less than 10% in their nocturnal systolic blood pressure. The dipper reversals had their nocturnal blood pressure figures higher than the daily figures. Pulse pressure was defined as the difference between systolic BP and diastolic BP [9]. In our study, we considered as high a pulsed pressure (PP) ≥60mmHg [9-11]: A white coat hypertension is defined by the presence of an hypertension during the consultation at the clinic that showed normal on the 24h ambulatory measurement [8]. Masked hypertension is defined by the presence of normal blood pressure figures in the clinic and a high BP in ambulatory care. It is the opposite phenomenon of the white coat HT. Resistant hypertension or refractory hypertension is defined as persistent hypertension despite optimal antihypertensive triple therapy including a diuretic [8]. The data collected were entered using a questionnaire developed by Sphinx plus 5 software.

Results

A total of 122 patients were recruited during the study period. The average age of the population was 53.22 ± 13.19 years with extremes of 25 and 85 years. The female sex predominated with a sex ratio M / F of 0.69. The majority of the population had hypertension ranging from 1 year to 10 years. In our study, 81 patients were taking antihypertensive therapy, the majority of them on dual therapy (58%). Physical inactivity (59.80%), menopause (68%) and diabetes (36.88%) were the most common risk factors (Table 1).

In the diagnostic indication for high blood pressure, ABPM was normal in 36.1% of cases. We found 13 profiles simulating a white coat HT, ie a rate of 36.1%. Among them were nine female patients. ABPM was requested in 66.4% of cases for a therapeutic evaluation (Table 2). In the context of this therapeutic evaluation, 27.2% of the patients were well controlled. Resistant hypertension was found in 7.37% of cases.

Table 2: Distribution of patients according to ABPM results.

SP : systolic pressure DP : diastolic pressure