Table 2.

Distribution of key findings.

AUTHOR	OUTCOME AND MEASUREMENT	KEY DETERMINANTS OF HYPERTENSION CONTROL	KEY FINDINGS
Maginga et al., 2015	Medication adherence: MMAS-4 Knowledge: Self-developed pretested questionnaire	Good knowledge (OR = 2.50, 95% CI, 1.00–6.10, p = 0.047) Attitudes (OR = 2.70, 95% CI, 1.00–7.10, p = 0.004) Practices (OR = 5.40, 95% CI, 2.30–13.0, p < 0.001)	Patients (47.7%) had controlled hypertension. Obesity and higher medication costs were associated with decreased control. There was high adherence (56.0%) to medication. Participants had moderate scores for knowledge (41.0%), attitudes (45.3%), and practices (49.3%).
Berhe et al., 2017	Medication adherence: MMAS Other determinants: Self-developed questionnaire	Treatment at general hospitals (OR = 1.89, 95% CI 1.26–2.83) Previously uncontrolled BP (OR = 0.30, 95% CI 0.21–0.43) Treatment regimens with diuretics (OR = 0.68, 95% CI 0.50–0.94) Age (OR = 0.99, 95% CI = 0.98–1.00)	BP was controlled in 37.0%, and treatment was intensified for 23.0% of patients with uncontrolled BP. The antihypertensive medication adherence rate (MMAS ≥ 7) was 40.0% and 57.0% for the lower cutoff (MMAS ≥ 6).
Labata et al., 2019	Hypertension self-care practices: Adapted H-SCALE questionnaire	Normal weight (AOR = 1.82, 95% CI = 1.07–3.09) a predictor of medication usage Good self-efficacy (AOR = 2.58, 95% CI 1.47–0.52) a predictor of a low-salt diet Female predictor physical activity (AOR = 0.51, 95% CI 0.30–0.88) and nonsmoking (AOR = 3.62, 95% CI 1.21–10.85)	61.9%, 30.5%, 44.9%, 88.3%, 93.5%, and 56.9% were adherent to medication, low-salt diet, physical activity, alcohol abstinence, nonsmoking, and weight management, respectively. Adequate knowledge of hypertension was 2.58 times more likely, and females were less likely to adhere to physical activity.
Niriayo et al., 2019	Self-care behaviors: H-SCALE Beliefs about medication: Belief about medicine questionnaire (BMQ)	Rural resident (AOR = 0.45, 95% CI: 0.21–0.97) Comorbidity (AOR = 0.16, 95% CI 0.08–0.31) Negative medication belief (AOR = 0.25, 95% CI 0.14–0.46)	Antihypertensive medications adherent (48.2%) and recommended physical activity (44.9%) Female (AOR = 1.97, 95% CI 1.03–3.75) and lack of knowledge on self-care (AOR = 0.07, 95% CI 0.03–0.16) were associated with alcohol abstinence and a low-salt diet.
Berhe et al., 2020	Adherence to self-care activities: H-SCALE	Age ≥ 50 years (AOR = 2.33, 95% CI 1.25, 4.35) Nonadherence to antihypertensive medication (AOR = 1.82, 95% CI 1.08–3.04) Nonadherence to physical exercise (AOR = 1.79, 95% CI 1.13–2.83) Nonadherence to low-salt diet (AOR = 1.98, 95% CI 1.18–3.31) Nonadherence to weight management (AOR = 2.06, 95% CI 1.31–3.23)	Prevalence of uncontrolled hypertension was found to be 48.6%. 26.1%, 59.1%, 73.9%, and 38.6% of hypertensive patients were nonadherent to medication, physical exercise, low-salt diet, and weight management, respectively.
Gebremichael et al., 2019	Self-care practice: H-SCALE Knowledge: Hypertension evaluation of lifestyle and management (HELM) scale	Sex (AOR = 2.25, 95% CI 1.09–4.65) Age (AOR = 3.26, 95% CI 1.03–10.35) Educational status (AOR = 4.20, 95% CI 1.30–13.55) Disease duration (AOR = 3.12, 95% CI 1.20–8.10) BP status (AOR = 2.72, 95% CI 1.25–5.92) Knowledge (AOR = 6.19, 95% CI 2.90–13.21)	Good self-care practice was only found among 20.3% of patients. Adherence to not smoking, antihypertensive medication, alcohol abstinence, dietary management, physical exercise, and weight management was found to be 99.1%, 74.1%, 67.2%, 63.1%, 49.4%, and 40.6%, respectively.
Okai et al., 2020	Blood pressure control: Pretested self-developed questionnaire with expert opinion	Sex (AOR = 3.53, 95% CI 1.73–7.25) Educational at junior high school (AOR = 3.52, 95% CI 1.72–7.22) Senior and junior high school (AOR = 2.64, 95% CI 1.40–6.66 and AOR = 3.06, 95% CI 1.03–6.67) Comorbidity (AOR = 2.41, 95% CI 1.32– 4.42) Increased pill burden (AOR = 0.27, 95% CI 0.10–0.73) Length of diagnosis of 2–5 years (AOR = 0.32, 95% CI 0.18–0.57)	No comorbidities (18.0%) had achieved hypertension control. Dyslipidemia (8.9%) had controlled hypertension (p < 0.006). Taking a higher number of antihypertensive pills per day was also associated with a reduced likelihood of attaining hypertension control. Most patients reported forgetfulness, side effects of medication, and high pill burden as reasons for missing their medications.
Herskind et al., 2019	Medication adherence: Medication possession ratio	Patients were most likely to cite transportation (81.0%), financial burden (69.0%), and schedule conflicts with work or other prior commitments (25.0%) as barriers to care.	Forgetfulness (12.0%) and lack of symptoms (9.0%) were challenges that patients reported facing in attending follow-up appointments. Home visits (13.0%), outreach (13.0%), and phone or mobile reminders (12.0%) were strategies to improve adherence.
Adidja et al., 2018	Medication adherence: MMAS	Forgetfulness (AOR = 7.90, 95% CI 3.00–20.80) Multiple daily doses (AOR = 2.50, 95% CI 1.20–5.60) Financial constraints (AOR = 2.80, 95% CI 1.10–6.90) Adverse drug effects (AOR = 7.60, 95% CI 1.70–33.0)	Participants (67.7%) were nonadherent to medications. BP was controlled in only 21.3% of participants and was better in those who were adherent to medication (47.5%, p < 0.010).
Gebrezgi et al., 2017	Facilitators and barriers to self-care: Self-developed interview guide and focus group discussion guide		Individual factors: economic barriers, stress, nonadherence to medications due to the use of traditional remedies, and difficulties and misconceptions about following physical activity guidelines influenced self-care. Individual knowledge, family, and government support were important factors to the patient’s success in the personal hypertension management.
Ware et al., 2019	Predictors of hypertension prevalence and management: World Health Survey (WHS, 2002–2004; 70 countries)	Waist-to height ratio > 0.5 and diabetes comorbidity were the most significant predictors of hypertension presence, awareness, and treatment. Women and individuals reporting lower salt use were more likely to be aware of and treated for hypertension.	Older age, larger waist-to-height ratio, lower levels of education, and diabetes comorbidity were also predictive of individuals with hypertension being aware of their status. Older age, female sex, larger waist-to-height ratio, diabetes comorbidity, lower levels of education, and not adding salt to food at the table were predictive of current antihypertensive medication use.
Mohamed et al., 2018	World Health Organization’s STEPs survey methodology tool	Among those aware, only 26.9% were on treatment, and 51.7% among those on treatment had achieved blood pressure control. Factors associated with hypertension were older age, higher BMI, and harmful use of alcohol.	The overall age-standardized prevalence for hypertension was 24.5%. Only 15.6% were aware of their elevated blood pressure. Factors associated with awareness were older age (p = 0.013) and being male (p < 0.001).
Adeniyi et al., 2016	Uncontrolled hypertension: Self-developed questionnaire	Unemployed status (p < 0.001) Excessive alcohol intake (p = 0.007) Consumption of a Western-type diet (p < 0.001)	Independent determinants of uncontrolled hypertension were unemployment, current excessive drinker of alcohol and adherence to Western-type diet.

Legends: AOR = adjusted odds rations; BMI = body mass index; BMQ = belief about medicine questionnaire; CI = confidence interval; HELM = hypertension evaluation of lifestyle and management; MMAS = Morisky Medication Adherence Scale; WHS = World Health Survey.