Evaluation of Blood Pressure Control and Associated Factors among Patients with Hypertension in Iraq: A Prospective Cross-sectional Study.

BACKGROUND: Uncontrolled blood pressure (BP) is a major contributor to cardiovascular disease-related morbidity and mortality. However, evidence regarding the rate and factors associated with uncontrolled BP in Iraq is scarce. The objectives of this study were a) to assess the magnitude of and factors associated with patient BP control and b) to investigate the patient-level prescribing patterns of antihypertensive medications, in a large Iraqi hospital.
MATERIALS AND METHODS: A prospective, cross-sectional study was conducted in the primary care centers of Al-Yarmouk Hospital in Baghdad, Iraq, between April 2018 and August 2018. Eligible patients answered standard survey questions and had their BP measured. Controlled BP was defined as <130/80mm Hg for patients with diabetes and/or chronic kidney disease and <140/90mm Hg for other populations.
RESULTS: During the study period, 300 patients were included; of which, 67.3% were female. The average age was 57.6 (9.2) years (range, 25-79 years). Among the 300 patients included, only 38.7% had controlled BP. In univariate analysis, poorly controlled BP was not associated with education, employment, smoking, comorbid conditions excluding diabetes, and therapeutic regimen used. In contrast, the strongest predictors of uncontrolled BP were age <60 years, male sex, and diabetes mellitus. The majority were prescribed monotherapy (53.0%), followed by dual therapy (38.7%), and triple therapy (8.3%). Angiotensin II receptor blockers or angiotensin-converting enzyme inhibitors were the most commonly prescribed medications at 74.7%, followed by beta-blockers at 29.3%, calcium channel blockers at 28.0%, and diuretics at 23.0%.
CONCLUSION: BP control was suboptimal. Effective feasible strategies should be implemented to increase BP control in Iraq to reduce hypertension-related complications.

Introduction

Hypertension is defined as a systolic blood pressure (BP) ≥140mm Hg or diastolic BP ≥90mm Hg and is a major independent risk factor for cardiovascular disease burden.[1] For every 20 or 10mm Hg increase in systolic BP or diastolic BP, respectively, from 115/75mm Hg, the mortality risk from cardiovascular disease and stroke is doubled.[2] This makes hypertension the most significant modifiable risk factor for cardiovascular, cerebrovascular, and renal disease.[123]

Improvements in mortality are related to lowering BP regardless of the antihypertensive medication selected.[4] Guidelines set different BP goals for patients based on their cardiovascular risk and concomitant conditions.[1] For example, the treatment target for a patient with certain comorbidities such as diabetes mellitus and chronic kidney disease (CKD) should be <130/80mm Hg; for all other patients with hypertension, the goal should be <140/90mm Hg.[12]

Medical therapy along with non-pharmacologic treatment should be started as soon as possible to achieve treatment goals and avoid complications.[12] Effectiveness of antihypertensive medications has been quantified in several large-scale studies.[56] First-line medications include angiotensin-converting enzyme inhibitors/angiotensin II receptor blockers (ACEIs/ARBs), calcium channel blockers, and diuretics.[12] Beta-blockers, another commonly prescribed medications, are reserved either for patients with compelling indications (e.g., heart failure, ischemic heart disease, and atrial fibrillation) or as an add-on therapy when first-line agents fail to achieve the BP goal in patients with severe or treatment-refractory hypertension.[12] There is evidence that BP control is poor when using monotherapy and that a minimum of two agents is usually required to reach target BP in the majority of patients.[27]

Despite advances in hypertension diagnosis and therapy, it has been previously reported that 30% of patients were unaware of their condition, 54% remained untreated, and only 34% achieved BP control.[1] Given the adverse clinical outcomes associated with poorly controlled hypertension, timely management and proper treatment intensification through regular follow-up are prudent to improve prognosis.[78] It is evident that achieving target BP for newly diagnosed patients with hypertension within 6 months of diagnosis appears to contribute to overall cardiovascular risk reduction possibly through the prevention of end organ damage.[89]

The prevalence of hypertension in adults in Iraq is known to be approximately 44%.[10] Indeed, studies describing hypertension treatment and outcomes in Iraq are limited. One study, however, showed that BP was only controlled in 48.2% of patients with diabetes.[11] Little is known about other cohorts and also about the factors that are associated with poor BP control. Uncontrolled hypertension may represent a major public health concern in Iraq but policy makers have limited epidemiological evidence needed to understand and tackle the problem. It is acknowledged that a solid evidence base to aid strategic planning and policy development in Iraq is currently missing.[12]

The aim of this study was to determine the level of BP control, associated factors, and the prescription pattern in a sample of Iraqi patients with hypertension, who were attending primary care centers in Al-Yarmouk Hospital in Baghdad, Iraq.

Materials and Methods

Ethical approval

This study was approved by the ethics committee of the College of Pharmacy, University of Mustansiriyah, and the study protocol was also approved by the Ministry of Health (reference number, 33418).

Study design and setting

This prospective cross-sectional study was conducted between April 2018 and August 2018 in Al-Yarmouk Hospital, a large publicly funded teaching hospital in Baghdad.

Inclusion and exclusion criteria

Participants were identified at outpatient clinics via convenience sampling. Any adult patient with hypertension attending primary care clinics for any reason, between April 2018 and August 2018, were eligible for the study. The presence of hypertension was adjudicated by asking patients to self-report on their medical history. Patients with severe mental illness, cancer, or who were aged >80 years were excluded from the study. In addition, patients who had stopped taking antihypertensive medications for more than 1 month, those with gestational hypertension, those newly diagnosed (<6 months), and those who did not know the names of their medications were also excluded. All study participants signed written consent to voluntarily participate in the study.

Data collection

The first author collected the data during biweekly visits to the hospital between April 2018 and August 2018. Data were collected by asking patients to answer questions in a structured questionnaire form developed by the researchers and which included age, gender, smoking status, education level, employment status, past medical history, duration of hypertension, and medication details (drug, dose, and frequency of dosing), Appendix A. BP was measured in all patients, using an electronic device (Rossmax Swiss Model: MG 150F; Rossmax Swiss GmbH, Berneck, Switzerland). Three readings were taken and average systolic and diastolic readings were subsequently calculated. Height, weight, and body mass index (BMI) were also measured in the nutrition clinic of the hospital. A calibrated stadiometer was used to measure patient height to the nearest 0.5cm, whereas a scale balanced to the nearest 0.5kg was used to measure patient weight while dressed in light clothing. This nutrition clinic does not operate on Thursdays, and BMI data were consequently not collected for all patients. All data were anonymously collected to protect patient confidentiality.

End points

The primary end point of the study was to assess the proportion of patients in which appropriate BP control was achieved, defined as an average BP reading of >130/80mm Hg for patients with diabetes and CKD and >140/90mm Hg for all other populations. The secondary end points were the factors associated with BP control and the prescribing pattern of antihypertensive medications.

Statistical analysis

In addition to descriptive statistics, a chi-square test (nominal data) and t-test (continuous data) were used to determine whether an association between patients’ demographic and other clinical characteristics and BP control was present. Binary logistic regression was then used to identify predictors independently associated with poor BP control. Variables with a P value <0.2 were entered as covariates into the regression analysis. Data were then analyzed using the Statistical Package for the Social Sciences (SPSS) software version 21.0 (INM Corp, Chicago, IL), and the P value was set at <0.05 to describe statistical significance.

Results

During the study period, 300 patients were recruited; of which, 202 (67.3%) were females. The average age was 57.6 years (range, 25–79 years). Among the 223 participants for whom BMI data were available, the majority were clinically obese (BMI > 30kg/m2, 139 patients, 62.3%). Only 27 patients (9%) were current smokers and 52 (17.3%) were currently employed. The average duration of hypertension was 8.9 (±7.7) years. Most patients (124, 41.3%) had ≥ two comorbidities; these included ischemic heart disease (44 patients, 14.7%), diabetes mellitus (105 patients, 35%), and dyslipidemia (173, patients, 57.7%) [Table 1].

Table 1

Comparison of demographic and clinical characteristics between patients with controlled versus uncontrolled blood pressure

Characteristics	Total	Uncontrolled	Controlled	P value
	n= 300 (%)	n = 184 (%)	n = 116 (%)
Sex				0.006
Female	202 (67.3)	113 (61.4)	89 (76.7)
Male	98 (32.7)	71 (38.6)	27 (23.3)
Age <60 years	173 (57.7)	116 (63.0)	57 (49.1)	0.015
Age ≥60 years	127 (42.3)	68 (37.0)	59 (50.9)
BMIa	31.7 (6.5)	32.4 (5.5)	31.8 (5.3)	0.428
Smoking status				0.966
Smoker	27 (9.0)	16 (8.7)	11 (9.5)
Ex-smoker	51 (17.0)	31 (16.8)	20 (17.2)
Nonsmoker	222 (74.0)	137 (74.5)	85 (73.3)
Education				0.785
Primary/no formal education	174 (58.0)	104 (56.5)	70 (60.3)
Middle/secondary school	40 (13.3)	26 (14.1)	14 (12.1)
Postsecondary	86 (28.7)	54 (29.3)	32 (27.6)
Employment status
Employed	52 (17.3)	32 (17.4)	20 (17.2)	0.973
Retired	50 (16.7)	33 (17.9)	17 (14.7)	0.458
Hypertension duration (SD), years	8.9 (7.7)	8.9 (8.0)	8.8 (7.3)	0.849
Medical history
Stroke	14 (4.7)	10 (5.4)	4 (3.4)	0.427
Acute coronary syndrome	18 (6.0)	8 (4.3)	10 (8.6)	0.129
Ischemic heart disease	44 (14.7)	25 (13.6)	19 (16.4)	0.506
Diabetes mellitus	105 (35)	84 (45.7)	21 (18.1)	<0.001
Diabetes duration (SD), years	7.9 (6.4)	8.2 (6.6)	6.9 (5.3)	0.340
Dyslipidemia	173 (57.7)	102 (55.4)	71 (61.2)	0.324
CKD	6 (2.0)	6 (3.3)	0 (0.0)	0.085
Rheumatoid arthritis	14 (4.7)	8 (4.3)	6 (5.2)	0.742
Thyroid diseases	14 (4.7)	7 (3.8)	7 (6.0)	0.372
Number of hypertension medications				0.456
1	159 (53.0)	102 (55.4)	57 (49.1)
2	116 (38.7)	66 (35.9)	50 (43.1)
3	25 (8.3)	16 (8.7)	9 (7.8)
Fixed-dose combination	78 (26.0)	48 (26.1)	30 (25.9)	0.966
Hypertension medication
ACEI/ARB	224 (74.7)	138 (75.0)	86 (74.1)	0.867
Beta-blocker	88 (29.3)	53 (28.8)	35 (30.2)	0.800
Calcium channel blocker	84 (28.0)	51 (27.7)	33 (28.4)	0.891
Diuretic	69 (23.0)	39 (21.2)	30 (25.9)	0.350

SD = standard deviation

aBMI available for 223/300 patients (73.7%)

Mean systolic BP was 139.7mm Hg (±22.9) and mean diastolic BP was 84.5mm Hg (±15.3). Only 116 patients (38.7%) had controlled BP. A more detailed breakdown of the various categories of hypertension included in the study is shown in Table 2, based on the classification criteria developed by the European Society of Hypertension and the European Society of Cardiology guidelines.[13]

Table 2

Level of blood pressure control for the study cohort

Hypertension severity	Definition	Total	No diabetes or CKD	Diabetic and/or CKD
		n =300 (%)	n = 192 (%)	n = 108 (%)
Normal	SBP <130mm Hg and DBP <80mm Hg	78 (26.0)	56 (29.2)	22 (20.4)
Mildly elevated	SBP = 130–139mm Hg and/or DBP = 80–89mm Hg	63 (21.0)	38 (18.8)	25 (23.1)
Stage 1	SBP = 140–159mm Hg and/or DBP = 90–99mm Hg	100 (33.3)	61 (31.8)	39 (36.1)
Stage 2	SBP = 160–179mm Hg and/or DBP = 100–109mm Hg	35 (11.7)	25 (13.0)	10 (9.3)
Stage 3	SBP ≥180mm Hg and/or DBP ≥110mm Hg	24 (8.0)	12 (6.3)	12 (11.1)

SBP = systolic blood pressure, DBP = diastolic blood pressure

In univariate analysis, age, sex, and diabetes mellitus were associated with BP control. In contrast, no statistically significant difference was observed between those with controlled and uncontrolled BP in education, employment, smoking status, other comorbid conditions excluding diabetes, and therapeutic regimen used [Table 1].

Binary logistic regression was performed and the results indicated that the male patients and younger patients (age <60 years) were twice as likely to have uncontrolled BP. Patients with diabetes mellitus were more than three times as likely to have uncontrolled BP [Table 3].

Table 3

Independent predictors related to uncontrolled blood pressure

Variable	Odd ratio	95% Confidence interval	P value
Diabetes mellitus	3.793	2.154–6.679	<0.001
Age <60 years	2.361	1.394–3.999	0.001
Male sex	1.993	1.149–3.458	0.014
Acute coronary syndrome	0.391	0.136–1.120	0.080
CKD	-	-	0.999

Most patients were prescribed monotherapy (159 patients, 53.0%), whereas 116 patients (38.7%) were prescribed dual therapy and 25 patients (8.3%) received triple therapy. Overall, ACEIs or ARBs were the most commonly prescribed medications (224 patients, 74.7%), followed by beta-blockers (88 patients, 29.3%), calcium channel blockers (84 patients, 28.0%), and diuretics (69 patients, 23.0%), predominantly as a combination low-dose therapy [Table 1].

The most commonly prescribed combination was diuretics + ACEI/ARB (49 patients, 16.3%), followed by a calcium channel blocker + ACEI/ARB (34 patients, 11.3%), and a beta-blocker + ACEI/ARB (25 patients, 8.3%). Table 4 provides a description of mono, dual, and triple antihypertensive therapy by pharmacological class.

Table 4

Combinations of mono, dual, and triple antihypertensive therapy by class

Pharmacotherapy	ACEI or ARB	Calcium channel blockers	Diuretics	Beta-blockers	Patients, n = 300 (%)
Monotherapy (n = 159)	X				91 (30.3)
		X			24 (8.0)
		X			3 (1.0)
				X	41 (13.7)
Dual therapy (n = 116)	X	X			34 (11.3)
	X		X		49 (16.3)
	X			X	25 (8.3)
		X		X	8 (2.7)
Triple therapy (n = 25)	X	X	X		10 (3.3)
	X	X		X	8 (2.7)
	X		X	X	6 (2.0)
	X		Xa		1 (0.3)

aPatient on two separate diuretics (thiazide and potassium-sparing diuretic)

The most commonly prescribed medications in both mono- and combination therapy were valsartan (ARB) (94 patients, 31.3%), followed by amlodipine (calcium channel blocker) (83 patients, 27.7%), hydrochlorothiazide (thiazide diuretic) (65 patients, 21.7%), lisinopril (ACEI) (35 patients, 11.7%), and bisoprolol (beta-blocker) (29 patients, 9.7%).

Discussion

To the best of our knowledge, this observational study is one of the first to describe hypertension control in detail in a large Iraqi cohort of patients. It also sheds light on the predictors of BP control and characterizes the current treatment pattern of antihypertensive medications. Only 38.7% of the study population achieved BP control. Most patients (53.0%) were prescribed monotherapy, whereas 38.7% received dual therapy and only 8.3% received triple therapy. Male sex, age <60 years, and diabetes mellitus were the strongest independent predictors of poor BP control. The most commonly prescribed medication class was ACEIs/ARBs, followed by beta-blockers and calcium channel blockers, whereas diuretics were the least prescribed.

Similar to other studies, the majority of this hypertensive cohort were women.[1415] The reasons for this are unknown but it has been reported that women have a higher rate of hypertension awareness and health-seeking behavior in contrast to men.[16] Conversely, men are known to engage less with proactive health care, and as hypertension is usually asymptomatic, they are consequently more likely to have uncontrolled BP.[17] Similarly, there was an association between BP control and sex, with men identified as being more likely to have uncontrolled BP than women.

The rate of BP control in this study was 38.7%. This proportion was lower than the finding of a previous Iraqi study that included only patients with diabetes and found 48.2% had controlled BP.[11] This rate was better than the 17.1% reported in a study carried out in Morocco and was comparable to the 37.0%, 39.0%, and 45.3% figures reported in studies conducted in Ethiopia, Europe, and Sudan, respectively.[14151819] However, BP control was lower in this study than that has been reported in the studies conducted in developed countries such as the US (64.0%) and Canada (66.0%).[2021] Disparities encountered in the findings of these studies were related to the difference in the thresholds used to define BP control, in addition to the differences in the study populations, and health-care systems.

Various factors have been associated with poor BP control including those related to the health-care system, the prescriber, and the patient (including socioeconomic state, education, and treatment adherence).[15] No association was found between education, employment, BMI, or the therapeutic regimen used and BP control. In this study, the main factors associated with poor BP control were male sex, age <60 years, and diabetes mellitus. Elderly patients often have more established multi-morbidity and hence greater experience with medications and/or more engagement with health-care professionals compared to younger patients.[1722] In contrast, younger patients are often committed to full-time jobs and as such they have relatively limited opportunities to seek health care.[17] Both of these factors may influence patient adherence. Diabetes as an independent predictor of poor BP control has been extensively reported in the literature, and ultimately such patients are a high-risk subgroup with a significantly increased risk of both macrovascular and microvascular complications and therefore these patients require strict blood pressure management.[172324]

In this study, 53.0% of patients were treated with monotherapy and 47.0% of patients were treated with polytherapy, levels that were similar to those found by a comparable study conducted in Jordan.[25] According to guideline recommendations, if the average dose of first-line antihypertensive medication is inadequate in achieving BP control, use of low doses of combination antihypertensive medications appears to be an attractive strategy to effectively control BP, reduce or prevent end organ damage, and reduce the likelihood of side effects compared to use of high-dose monotherapy.[12] Guidelines recommend dual therapy as the initial first-line therapy for patients who are unlikely to achieve BP target with monotherapy alone (i.e., patients with an elevation of 20mm Hg in systolic BP and 10mm Hg in diastolic BP).[2] Patients who fail to achieve the target BP level after 6–8 weeks of regular treatment with dual therapy would require stepping up to triple therapy.[26] No statistically significant relationship was observed between the number of medication used and BP control in this study.

The most commonly prescribed antihypertensive medications were ACEIs/ARBs, a prescribing pattern that has been reported in several other studies.[252728] Besides being first-line medications, it has been shown that ACEI/ARB therapy helps to delay or prevent the progression of CKD, and guidelines accordingly emphasize this approach as a compelling indication for patients with CKD or diabetes mellitus without contraindications.[12] More than one-third of this study population were diabetic and this could explain the high trend of ACE/ARB use.

Despite the wide availability of safe and effective treatment, BP control remains suboptimal in many countries.[171819] Adherence may play a significant role, as some patients may only take their antihypertensive medications when they experience certain symptoms.[29] Alternatively, patients may opt to stop their medication on experiencing initial side effects such as increased urination with diuretics.[30] The asymptomatic nature of the illness, which is often called a silent killer, requires additional efforts to increase medication adherence and decrease the proportion of patients with uncontrolled hypertension. Further work is needed to characterize medication adherence in Iraqi patients with hypertension. Other areas for interventions in Iraq may include proactive medication reviews, increasing patient knowledge regarding hypertension, and the need for regular medical therapy.[31] Pharmacists are increasingly seen as a mechanism to improve these factors in hypertension.[32]

Strengths and Limitations

To the best of our knowledge, this is the first study to comprehensively address the prescribing pattern of antihypertensive medications and BP control in a large Iraqi university hospital. However, our results should be interpreted in light of several limitations. No information is available for concomitant medications (e.g., over the counter nonsteroidal anti-inflammatory drugs), which could affect BP control.[33] Furthermore, guidelines recommend that BP be measured on at least two occasions; however, this study only recorded BP during one visit.[2] No information was collected with regard to long-term medication adherence. The study was also conducted only in one hospital, and it may consequently be difficult to generalize the findings.

Conclusion

The study findings indicated that BP control is suboptimal with only 38.7% of patients achieving the target BP. Male sex, age <60 years, and diabetes mellitus were found to increase the risk of poor BP control. Currently, monotherapy, rather than dual or triple therapy, is the most common treatment strategy. ACEIs/ARBs are the most commonly prescribed antihypertensive drug class. Commendable efforts are warranted to increase BP control in Iraq with the objective of ultimately decreasing the risk of cardiovascular events, renal failure, and overall mortality.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

Age:	Weight (kg):	Height (cm):
Gender	Male:	Female:
Smoking status
Current smoker
Ex-smoker
Nonsmoker
Education
No formal education, primary
Middle, secondary
Postsecondary
Employment
Employed
Retired
Past medical history
1. Dyslipidemia	Yes:	No:
2. Diabetes mellitus	Yes:	No:
Duration of diabetes (years):
Last HA1c recent reading if available:
3. COPD	Yes:	No:
4. Stroke	Yes:	No:
5. MI or UA	Yes:	No:
6. HF	Yes:	No:
7. IHD (stable angina)	Yes:	No:
8. Rheumatoid arthritis	Yes:	No:
9. CKD (stage 4 or 5)	Yes:	No:
10. Atrial fibrillation	Yes:	No:
11. Asthma	Yes:	No:
12. Other:
Duration of hypertension (years)
Blood Pressure reading 1:	SBP1:	DBP1:
Blood Pressure reading 2:	SBP2:	DBP2:
Blood Pressure reading 3:	SBP3:	DBP3:
Medication	Dose	Frequency of dosing
1.
2.
3.
4.
5.

SBP = systolic blood pressure, DBP = Diastolic blood pressure, HA1c = hemoglobin A1c, COPD = Chronic Obstructive Pulmonary Disease, MI = myocardial infarction, UA = unstable angina, HF = heart failure, IHD = ischemic heart disease