1. Introduction
About 67% of deaths in the world (38 million) occur due to non-communicable chronic diseases (NCDs). A World Health Organization (WHO) projection presents the number of NCD deaths increasing each year, with an increase of three million more deaths every four years [
1,
2]. Among the NCDs, cardiovascular diseases (CVDs) stand out, which are responsible for 17.9 million annual deaths worldwide. Systemic arterial hypertension is of great importance among CVDs, as it is highly prevalent in the world population and can be considered an aggravating factor for other CVDs [
3,
4].
Hypertension affects approximately 45–67% of elderly individuals and 2–12% of children and adolescents worldwide. The prevalence in adult individuals is estimated at approximately 19–42.5% in emerging countries. Its severity is related to the impairment of target organs, such as kidneys, heart, and brain [
1,
3,
5]. According to the WHO, hypertension is considered the main risk factor for the occurrence of other diseases of the circulatory system [
2], as it is known that an increase of 10 mmHg in systolic blood pressure is capable of increasing by 25% the risk of developing CVDs, representing a risk association equal to 1.2 in observational studies [
6,
7].
Health technologies characterized as services capable of managing treatment preventively become contributory to the management of hypertensive patients with the promise of producing results of better effectiveness in blood pressure control and cardiovascular risk reduction [
8,
9]. Pharmaceutical care (PC) is a model of professional practice that constitutes a set of actions and services performed by the pharmaceutical professional, which considers the biopsychosocial sphere of the individual, family, and community, working along with the health team, focusing on the prevention and resolution of problems of health, further to the promotion, protection, damage prevention, and recovery of health, including not only the clinical assistance dimension but also the technical pedagogical dimension of health work. In this model of practice, the pharmacist assumes responsibility for managing people’s healthcare, which must be shared with the health team and the actions agreed upon with the patient/family [
10,
11,
12].
PC works on adherence to medication, lifestyle changes, dietary sodium restriction, moderation of alcohol consumption, a balanced diet, weight reduction, regular physical activity, and smoking cessation, which are important changeable factors in the management of hypertension. In this way, PC develops a service capable of modifying those factors and providing care that improves the effectiveness and safety of the treatment—medication therapy management (MTM). Thus, MTM-PC is a health technology that is very important in enabling the aid of hypertension management regarding classic treatment with calcium channel blockers (CCB), angiotensin converting enzyme inhibitors (ACE inhibitors or ACE-I), angiotensin receptor blockers (ARBs), and diuretics, and is also related to treatment with new drugs [
9,
10].
The PC results related to MTM show that there is a positive clinical impact on the reduction in blood pressure and cardiovascular risk, but the impact of different models, as well as their results regarding the scenario in which it is inserted, are unknown in the literature [
13,
14]. Furthermore, in health management and planning, decision-making based on the highest possible degree of evidence is necessary [
15,
16,
17]. Even if the PC produces good results for the treatment of hypertension, it is necessary to evaluate the existing MTM-PC models, their characteristics and the influence of the scenarios for their insertion in order to define a profile adjustable for each reality that generates results with greater precision, in order to incorporate this service as a feasible health technology for different realities of healthcare systems [
8,
18].
Decision-making processes in health are carried out either in a subjective way, which is more related to the previous conceptualizations of the decision maker and their subjectivity, or in a systematized way, which is more rational and is revealed to culminate in the most effective process. In the latter, it is essential to observe the sources of information as well as the origins of the results that will support decision-making [
19]. The greater the robustness of the analysis on the source of information for decision-making, the greater the assertiveness of the decision. In addition, the highest degree of evidence must be considered. In view of the classifications of epidemiological studies, the satisfactory degree of evidence for assertive decision-making in health is at the top of Chiappelli’s pyramid, such as systematic review studies with meta-analysis. In this sense, a systematic review with meta-analysis and, mainly, meta-regression is capable of assigning better precision in the results to answer the review question and also to distinguish itself from other reviews. There are some reviews on this theme, but they are poor at describing different services and models of MTM-PC, as well as summarizing the characteristics of those models compared to their results [
15].
This study was reasoned on the hypothesis that PC is a health technology to be incorporated into health systems to improve effectiveness in reducing blood pressure and cardiovascular risk in hypertensive patients, and its effects may differ and be measured in different models of MTM. In this context, the aim of this study was to generate evidence for the treatment effect on blood pressure and cardiovascular risk from different models of MTM by PC for hypertensive patients in the context of primary healthcare.
2. Results
The initial search yielded 8142 records of which 89 articles underwent full-text evaluation, and 41 articles were selected and 48 were excluded (
Table S1). Their selection was consistent with the researchers’ agreement [Kappa = 0.86; 95% CI, 0.66–1.0; (
p < 0.001)]. It is noteworthy that in the search carried out in the grey literature, no study was found that met the inclusion criteria and mastery of the review after reading the full text (
Figure 1).
According to the 41 studies eligible for this systematic review, it was possible to report that the countries with more published studies within this theme are the USA with 17 (41.5%) and Brazil, 5 (12.2%). Among these studies, 25 (61.0%) are randomized controlled trials (RCTs); 3 (7.3%) are clinical trials without randomization; 10 (24.4%) represent clinical trials defined as quasi-experimental; 3 (7.3%) are observational studies; and 32 studies (78.1%) present sample calculation or at least report the number of patients eligible for the study. The mean duration of the studies is 18 ± 16.5 months and, 24 (58.5%), 9 (21.9%), and 15 (36.6%) studies feature randomization, blinding, and patient allocation concealment, respectively. The total number of patients in the intervention group is 4195 and in the control group 4978, with respective follow-up losses of 1338 and 913 (
Table 1).
The quality of the studies was assessed and discriminated by the classification of Downs and Black [
61]. The highest score achieved is 96.3 and the lowest is 22.2. The percentage of studies classified as having high evidence is 19.5% and with flawed evidence is 29.3% (
Table 2).
In the qualitative evaluation of the MTM models from PC, it was possible to measure the mean of 10.0 ± 10.7 months of follow-up and a median of 6 months, with a minimum and maximum of 2–24 months. The mean of consultations is 7.7 ± 4.9 and the consultation time is 29.0 ± 8.0 min. The clinical scenario consists of 19 (44.2%) services developed in community pharmacies, 17 (39.5%) in healthcare facilities, and 7 (16.3%) in outpatient clinics. The most prevalent MTM models are those based on methods developed by the clinician themselves, an own model, 27 (65.9%); followed by the pharmacotherapy workup method 7 (17.1%); Dáder 5 (12.2%); and SOAP 1 (2.4%). Most MTM models have an educational/patient empowerment character, 34 (82.9%), and are structured with multidisciplinary support, even if it is just a pharmacist/physician, 26 (63.4%) (
Table 3).
According to the total of 9173 patients, a profile could be defined whereby the mean age is 61.6 ± 6.6 and 61.9 ± 5.5 years for the intervention and control groups, respectively. In addition, there is a higher prevalence of male patients, with high education, and white skin color for both groups (
Table 4).
The number of patients with diabetes; smokers; and alcoholics is992 (30.6%) and 1236 (33.8%); 491 (21.2%) and 473 (22.1%); and 257 (19.5%) and 263 (21.7%) for the intervention and control/exposure groups, respectively. Most patients are level 1 and 2 obese, totaling 1740 (60.0%) in the intervention group, and 1424 (57.2%) in the control group. Among the previous history of diseases associated with hypertension, ischemic heart disease has the highest prevalence, with 227 (17.8%) and 255 (20.1%) patients for the intervention and control groups, respectively. It is noteworthy that out of the nine studies that evaluate the quality of life, 88% of them show that there was an improvement in the quality of life of hypertensive patients followed-up by the MTM-PC, which was measured by standard instruments to assess the quality of life. It is highlighted that the mean increase in the score of quality-of-life was 13.4 ± 10.7% (
p = 0.047) (
Table 5).
The proportion of pressure control profile is 1673 (38.1%) and 2350 (63.3%) patients at the end of follow-up when compared the group with conventional care and the group with MTM by PC, respectively. The proportion of patients with total cholesterol, HDL, LDL, and triglycerides at satisfactory levels for both groups is 172 (32.7%) and 314 (59.6%) (
p = 0.001); 200 (37.9%) and 206 (39.2%), (
p = 0.650); 236 (44.9%) and 341 (64.8%), (
p = 0.001); and 240 (45.5%) and 290 (55.0%), (
p = 0.002), respectively (
Table 5).
Regardless of the study design, there is a reduction in blood pressure when comparing the control/exposure and intervention groups. However, neither the study by Tobari et al. [
59], a randomized clinical trial, or Erickson et al. [
54], an observational study, have any evidence of improvement in blood pressure and the study by Robinson et al. [
57], a non-randomized clinical trial, shows evidence of difference only for systolic pressure. Mean reductions in systolic (SBP) and diastolic blood pressure (DBP) are 6.8 and 3.7 for randomized clinical trials, 17.3 and 10.2 for non-randomized clinical trials, and 3.9 and 0.6 for observational studies, respectively (
Table 6).
The randomized clinical trial studies with quality assessed as good-to-high evidence were selected to be included in the meta-analysis. The treatment effect of MTM-PC was analyzed firstly for blood pressure. The mean reduction in blood pressure in the intervention group compared to the control group is −7.71 (95% CI, −10.93 to −4.48) and −3.66 (95% CI, −5.51 to −1.80) (
p < 0.001) for SBP and DBP, respectively. It is important to consider the random model for the results due to the high heterogeneity between the studies, which is 81% and 77% (
Figure 2).
Due to the heterogeneity between the studies, a sub-analysis was performed based on the group of different variables: study quality score (0–100% according to the level of evidence); clinical setting (where the PC was developed, pharmacy, facilities, clinic); method for developing the MTM (own, Dáder, PW, SOAP). It is likely that if we removed the studies by Vivian et al. [
46] and Skowron et al. [
42], heterogeneity between studies may decrease, although in this case, the
p-value is 0.0994. The same situation is represented for the other subgroup analyses, whose
p-value is 0.6143 and 0.9916, for the clinical scenarios and the method, respectively. The results are shown in
Figure 3,
Figure 4 and
Figure 5.
The funnel graph shows that there is considerable accuracy in the results of the studies and it also shows that there is no publication bias influencing the results,
p-value = 0.8539 (
Figure 6).
Relative risk was analyzed for cardiovascular risk over ten years, as measured by the ASCVD risk scale. It was only possible to calculate the risk in three studies. The results show that there is a reduction in the cardiovascular risk of hypertensive patients when there is MTM by PC for hypertensive patients. In this sense, the PC works as a protective factor when analyzed both by the fixed model and by the random model, relative risk (RR) = 0.561 (95% CI 0.422–0.742) and RR = 0.570 (95% CI 0.431–0.750). Although the studies can be considered homogeneous, I² = 0%, it makes no sense to state this possibility, due to the smaller number of studies for the calculation of “
n” in the I² formula (
Figure 7).
The funnel plot for analysis of cardiovascular risk shows that there is a lower possibility of publication bias; although there are few studies for this analysis, the tendency would be to increase the RR. However, there is no asymmetry to support a bias,
p = 0.4949. It is noteworthy that more than 50% of the studies show good accuracy, greater than 30% (
Figure 8).
Data meta-regression was performed, as the quality scores of the studies may be associated with their results regarding cardiovascular risk over ten years. It is not possible to achieve a level of good evidence due to the number of studies, but meta-regression may suggest that the higher the study quality, the lower the protective impact of PC on cardiovascular risk,
p = 0.2532 (
Figure 9).
3. Discussion
The selection of studies for the review has a satisfactory agreement between the two researchers, classified as almost perfect, which shows that the review is consistent with its protocol regarding the robustness of the methods used for the inclusion of studies [
62]. The quality evaluation of the included studies shows that the clinical trial studies have better scores than the observational studies in general, 70.7%, and the greatest number of studies included in the review have a score above 60 (0–100). The mean quality score is 70.8 ± 19.3 for randomized clinical trials, 52.7 ± 15.3 for non-randomized clinical trials, and 51.8 ± 19.3 for observational studies. However, studies with higher chances of bias, classified as poor or flawed evidence (51.2%), surpass the total number of studies with good and high evidence (48.8%). It is noteworthy that the better the quality of the study, the greater the chances of having better accuracy of the results, and this could be verified in this review, in which the types of studies with a higher level of evidence present positive results from MTM-PC [
15,
63].
Pharmaceutical interventions in the MTM process, either alone or in collaboration with other health professionals, are recognized to improve blood pressure control. However, pharmaceutical interventions can have a magnitude of differential effects on blood pressure ranging from very large, modest, to no effect. This fact can be determined by the heterogeneity of the MTM-PC models and in the methods of the study that evaluate that model [
64]. It is noteworthy that this review shows that most MTM-PC models are developed by the pharmacist or clinical group, the own model grounded at default methods, maybe because they are better adapted to each reality.
Additionally, when analysing those studies that present poor results for blood pressure control compared to the others in this review, we find that there is no interference. In this case, it is noted that the studies by Bajorek et al. [
48] and Modé et al. [
55] present results in which MTM does not promote improvement in blood pressure values. The quality of studies that show improvement in blood pressure values was compared with the quality of these two studies. The adjusted value of the Mann–Whitney test, w = 7.00 (
p= 0.036), shows that the quality of these two studies, measured by the Downs and Black [
61] instrument, is lower than the other studies that show improvement in arterial blood pressure values.
It is noteworthy that there is evidence for homogeneity between the groups compared in this review regarding sociodemographic characteristics, as well as for the variables that cannot be modified by the intervention of the studies (staging of the degree of hypertension, presence of diabetes, smoking, alcoholism, obesity, body mass index, abdominal circumference, and history of diseases). Homogeneity between groups is an important factor for comparing them and obtaining the measure of the clinical effect of an intervention, which gives greater accuracy to the results of this review [
65].
In addition, there is better pressure control of patients in MTM by PC, of which 25.2% more have blood pressure control and improvement in lipid profiles compared to the group with conventional health care. The importance of controlling blood pressure and improving the lipid profile directly infers in the management of hypertensive patients, both clinical regarding the reduction in cardiovascular risk, and managerial for improving the profile care in the sense to pass from emergency to a preventive scope and, consequently, to promote changes in the pharmacotherapy [
60].
The meta-analysis of this study shows an RR less than 1 [0.56; 0.42–0.74, 95% CI] for the cardiovascular risk over ten years, which represents a protective character for hypertensives regarding the CP treatment effect [
66]. The measure of effect is able to show the efficacy of MTM by PC equal to 44.0% (26.0–58.0, 95% CI), an important result when compared to other preventive interventions [
67]. It is like that this result may have a strong association with pharmaceutical interventions related to drug-related problems, which have an impact on the effectiveness and safety of pharmacological treatment, with a consequence of improved adherence and lifestyle [
68,
69].
In addition, there is evidence for a mean reduction in systolic and diastolic pressures. These results are relevant, as a decrease of 5.7 mmHg is capable of reducing the absolute risk of acute myocardial infarction related to ischemic heart disease, stroke, and heart failure by 3.7 years, by 2.00%, 2.40%, and 2.20%, respectively. This study shows a reduction between 4.48 to 10.93 mmHg in systolic pressure and 1.80 to 5.51 mmHg in diastolic pressure. Consequently, it can impact on the absolute risk reduction over ten years, reaching 8.74% for health complications from hypertension and 1.13% for the reduction of morbidities associated with hypertension [
70].
The subgroups’ analysis for quality of the studies, the clinical setting, and the follow-up models contribute to these results. The differences in the clinical scenario show that the community pharmacy presents a higher impact on blood pressure reduction, but these subgroups have the study of Bajorek et al. [
48], which presents negative results for blood pressure. It could influence the confidence interval for this group. However, the other scenarios have evidence for reducing blood pressure. Although there are some differences among the models of MTM-PC on blood pressure, all models are shown to be efficient. There is evidence for own models to be able to cause the better mean difference in blood pressure, −7.60 [IC 95%, −12.62; −2.58] and −3.26 [IC 95%, −6.66; −0.13], followed by SOAP −6.89 [IC 95%, −11.23; −2.54] and −3.09 [IC 95%, −5.37; −0.80]. Additionally, the PW model has a good balance for reducing systolic and diastolic pressure, PW −7.43 [IC 95%, −11.34; 3.53] and −4.11 [IC 95%, −6.02; −2.21]. The Dáder model has a confidence interval passing by one, which means that it can have no good results for blood pressure, despite it presenting a better range for reducing blood pressure −8.51 [IC 95%, −18.95; 1.92] and −4.01 [IC 95%, −6.05; −1.96].
The results show that these subgroups do not influence the discrepancies in results between studies for blood pressure control, (
p-value > 0.05). Thus, it is noted that the hypothesis that the different models of MTM by PC can influence, in a positive or negative result, does not apply [
64]. Therefore, it is possible that MTM-PC models, which are not standard to the existing philosophy of PC and that are not adapted to the regional reality, cultural, and epidemiological characteristics, and to the needs of the health systems, are capable of providing discrepant and even ineffective results for reducing arterial blood pressure [
71].
The result of the clinical impact of PC can have repercussions on the health system as a whole, since primary health care is recommended to be resolutive and preventive to improve the efficiency of the system. In this sense, it is noteworthy that MTM by PC is able to reduce hospital readmissions of hypertensive patients by an average of 30 days [
72]. It is known that as the level of complexity of care increases, the cost per patient for the health system also increases. In this way, PC may be able to optimize resources and save costs in health systems, with the ability to improve the patient’s quality of life, as evidenced in the results of this review [
73].
It is noteworthy that the results of this meta-analysis refer to hypertensive patients undergoing preventive care and follow-up in primary health care. Thus, the profile of the MTM models by PC can be delineated with the average number of eight consultations, with an average duration of 30 min among all consultations, with the first consultation taking the longest time from around 40 min to 1 h and 50 min, with a mean of ten months and median of six months of patient follow-up. In a direct cost analysis, it is shown that optimizing resources tends to be more cost-effective in six months of follow-up of patients with MTM by PC [
70], which can cost USD 75 to increase in a unit the blood pressure control of hypertensive patients [
74]. In the cost-effectiveness analysis of the MTM by PC for hypertensive patients, it is shown that the initial investment in the service is rewarded in outcomes and in return on investment even after three years of patient discharge, presenting the cost of USD 128.03 for improving by one unit the blood pressure of hypertensive patients [
75].
In addition, it is highlighted in the profile of the MTM models developed in PC that community pharmacies and primary health units are the most prevalent scenarios for their insertion in the scope of primary health care. Additionally, added to the results of the MTM profile developed in the PC in this review, the important role of health education and the insertion of other PC services in its development in an interdisciplinary and collaborative way with other clinicians is highlighted, such as through pharmacotherapy review, medication reconciliation, therapeutic medication monitoring, and health condition management [
71].
This study had some limitations. Several included studies had incomplete data for the cardiovascular risk calculating, and this fact made it difficult to measure the cardiovascular risk for different models and scenarios. If we tried to estimate the cardiovascular risk for different MTM-PC models and scenarios, we would need to perform another review, which certainly would completely change the aim of this review and not evaluate the influence of different models of MTM-PC and other important characteristics of their effects, since there are different instruments to calculate the cardiovascular risk, which must be considered when the calculation is ready in the study, and also there are different diseases that are applied to cardiovascular risk for their management [
76,
77].
The most important models for MTM-PC in this theme are identified in the included studies, but there are other models such as therapeutic outcomes monitoring (TOM), OLD CARTS, and others that are not identified. Actually, these methods are unhabitual by PC, and they are not very well incorporated into the clinical practice [
71]. Consequently, it would not impact on the evidence level of the MTM-PC on hypertension management.
In fact, it is possible to refer to the fact that the MTM-PC can be an adjuvant health technology to new antihypertensive therapies when in the market clinical phase, most likely due to carrying out nonpharmacological lifestyle interventions along with antihypertensive drug therapies [
78]. Consequently, it can aid to improve the numbers of poor blood pressure control, which are alarming, as only 10% on average have their blood pressure controlled in low-income and middle-income countries [
79].
5. Conclusions
Most of the studies included in this review have a quality score above 60% and almost half have a good-to-high evidence rating for the results. Among the MTM-PC models analyzed in this systematic review, most are from the USA. Own models, reasoned on standard models, emerge as the most prevalent. Sequentially, from the profile obtained from the MTM by the PC, it was noted that the average time for monitoring hypertensive patients is ten months, with an average of eight 30 min consultations, with the exception of the first consultation being longer, being approximately one hour and 30 min. It is not possible to calculate the average number of patients to be consulted by the pharmacist in the month because many models originate from epidemiological studies and do not refer to the feasibility regarding the capacity of consultation.
There is evidence for the mean reduction in blood pressure and also for better blood pressure control, consequently, there is a reduction in cardiovascular risk over ten years associated with the improvement in quality of life of hypertensive patients assisted in the MTM by PC, which can work as a protective factor to hypertension, presenting a good efficiency to avoid incidence of CVDs in hypertensive patients. Thus, the community pharmacy setting is important for the better reach of MTM-PC impact, but the ambulatory setting has better evidence for reducing blood pressure. Regarding different models, the own model of MTM-PC has the better impact and PW is the most balanced for reducing blood pressure. However, it is highlighted that further exploration is needed.