On the transition from a nurse-led hypertension clinic to hypertension control in primary care: identifying barriers to and factors acting against continuous hypertension control

Abstract

Many hypertensive patients are not treated to target and hence do not benefit fully from the blood pressure-related improvements in cardiovascular health. Hypertensive patients who had primarily been treated to a target goal in a nurse-led hypertension clinic were re-examined to evaluate whether their target goal blood pressure was maintained after their discharge from the hypertension clinic for further control in primary care, and to evaluate potential barriers to and factors acting against continuous hypertension control. The median observation time was 3.6 years (range 3 months to 7.9 years). Only 45.2% of the patients were well controlled at the time of re-examination. No patient-related factors (age, body mass index, gender, attitudes towards medication) predicted the outcome. Two factors were significant in the reduction in continuous hypertension control: the cooperation between the patient and health personnel and the shared commitment towards the target goal were discontinued; and many patients did not make control visits to the general practitioner’s office. In conclusion, maintained strict control of hypertension requires both continued close collaboration between the patient and health personnel, with an emphasis on treatment goals, and systematic control visits.

Keywords:

• Nurse-led clinic
• hypertension control
• treatment goals
• primary care

Introduction

Hypertension treatment is initiated to prevent cardiovascular and renal complications, and it is important to reach and maintain low blood pressure (BP) values in order to lower cardiovascular and renal complications.[1,2] The benefit of BP lowering is greater in well-controlled hypertensives than in hypertensives who are not treated to a target value. However, many hypertensives do not achieve their target goal.[3–8] The Holbaek Hypertension Clinic presented data showing that 95% of high-risk patients reached the target BP value (<140 mmHg) in systolic blood pressure (SBP).[9] Results from other nurse-led hypertension clinics using pharmacological as well as non-pharmacological intervention reported that the nurse-led hypertension clinics are effective in managing the early phase of hypertension treatment where the target goal is reached.[10–12] Results from some nurse-led clinics report that the clinics are also effective in long-term control of hypertension.[13] However, after completing treatment in a nurse-led hypertension clinic most patients are followed in primary care settings.

The aim of this study was to re-examine patients who initially were treated to a very high rate of hypertension control in Holbaek Hypertension Clinic [9] and thereafter discharged to primary care. The re-examination was performed investigate the long-term control of hypertension, and barriers to and factors acting against continuous hypertension control.

Methods

Patients

Over a period of 8 years (2004–2012), 294 patients with hypertension and high or very high risk-factor levels were treated in Holbaek Hypertension Clinic. During a total period of 9 years (2004–2013), 23 of the patients died (8%). After completing treatment in the hypertension clinic, the remaining 271 hypertensives were all controlled in primary care, and after a median of 3.2 years (range 0.2–7.9 years) they were invited by letter to a re-examination in the hypertension clinic. Of these, 117 (43%) accepted the invitation, answered the questionnaires and underwent the examination programme. At the initial admission to the hypertension clinic, their BP (mean ± SD) was 168.6 ± 26.0/93.9 ± 15.6 mmHg. At the time of discharge from the hypertension clinic, the mean SBP was 134.2 mmHg and 95% were well controlled.[9]

Nurse-led clinic

Difficult-to-treat patients were referred to the hypertension unit and initially seen by a senior consultant. Thereafter, nurses administered a treatment algorithm and an educational effort aimed at providing information on healthy lifestyles and awareness of adequate hypertension control.[9] The patients were encouraged to take an active part in BP measurement and treatment. All patients were thoroughly instructed in measurement techniques and observed while measuring in order to check for measurement mistakes. Home BP readings were discussed at the following visit to the hypertension clinic to give the patients feedback on their home BP measurements. All possible side-effects of the medicine were evaluated and, if necessary, the patients were treated with alternatives according to the standard list of medicine. Whenever possible, the cheapest medicine was chosen. The patients were instructed in the target value, and that an SBP of 140 mmHg or higher elicited consideration for the next step in the treatment algorithm. Thus, the patients were encouraged to take an active role in BP measurement and treatment in close cooperation with the nurses to achieve the target goal. Having reached the target goal, the patients were discharged from the hypertension clinics, and they were recommended lifelong hypertension control at the general practitioner’s (GP’s) office; the GP also refills prescriptions when they run out. The GPs have full access to all electronic material from the hypertension clinic. The patients are not called for regular control in primary care automatically but must take the first initiative themselves.

Blood pressure measurements and other procedures at re-examination

The re-examination of the patients included three different BP measurement methods: (i) an ambulatory (24 h) BP measurement (Boso TM 2430, Jungingen, Germany); (ii) triple BP measurements on a fully automatic device (WatchBP Office, Widnau, Switzerland) with the nurse present during BP measurement; and (iii) three BP values measured with the same device, but with the patient alone in the room.[14] It was decided by randomization whether the first clinical BP measurement was performed by method (ii) or (iii). BPs are presented as the average value of three measurements with appropriate cuffs according to arm circumference. BPs measured on the arm with the highest average SBP were used in the statistical evaluation. All BPs were measured with the patient in the sitting position after 5 min rest. Ambulatory BP measurements were performed during usual daily activities.

Height and weight were measured and the body mass index (BMI) was calculated. Waist circumference was measured. Blood tests were analysed for cholesterol, creatinine, blood sugar, haemoglobin and electrolytes. Morning spot urine was analysed for albumin–creatinine ratio.

Questionnaires

A questionnaire was completed at the time of the interview. The patients answered questions on lifestyle, medication, attitudes towards medication, adverse effects, self-estimated compliance, self-reported health, education, income, knowledge of hypertension, the latest BP measured by a physician and the physician’s evaluation of the last BP. The patients picked an answer from a number of options in the questionnaires.

Statistics

Data are presented as proportions, median values or mean values ± SD. Simple linear regression models were used to evaluate any time-dependent differences in SBP. Differences in frequencies were tested by chi-squared tests.

Values of p < 0.05 in two-sided tests were considered significant. All analyses were performed with SAS software (SAS System for Windows, release 9.1; SAS Institute, Cary, NC, USA).

Results

The patients’ characteristics at re-examination are given in Table 1. At re-examination, 45.2% of the patients had clinic SBP below 140 mmHg. There were no significant differences between patients with successful control and patients with uncontrolled hypertension when comparing age, risk factors, gender, income, education, number of medicaments, adverse effects, self-reported compliance, attitude towards pharmacological treatment and knowledge of hypertension.

Table 1. Descriptive data at re-examination.

	n	Mean %	SD
Age (years)	117	64.7	10.96
Men (%)	117	58.1
SBP (mmHg)	117	142.4	15.6
Ambulatory SBP in daytime (mmHg)	32	142.1	15.70
SBP < 140 mmHg (%)	117	45.3
BMI (kg/m^2)	102	28.0	4.27
Non-smokers (%)	116	77.6
Less than 30 min exercise per day (%)	114	78.5
Diabetes^a (%)	117	29.9
Total cholesterol (mmol/l)	105	4.9	1.0
Low or no education^b (%)	117	86.2
School: ≤ 10 years (%)	117	87
Stroke (%)	116	12.1
IHD (%)	117	14.5
Alcohol (0–6 drinks a week) (%)	112	86
Microalbuminuria^c (%)	92	9.8
Diabetic nephropathy^d (%)	117	1.7

a Self-reported and/or blood sugar levels > 11.1 mmol/l;

b no education or technical training;

c urine–albumin/creatinine index ≥ 30 U;

d p-creatinine ≥ 150 mmol/l and diabetes.

SBP, systolic blood pressure; BMI, body mass index; IHD, ischaemic heart disease.

There was no linear association between the length of the observation time (interval between last examination in the hypertension clinic and re-examination) and SBP.

The patients were asked to report the last BP measured in primary care. A large proportion (30.8%) did not know the answer or had no BP measurement in the observation time (3.6 years; range 3 months to 7.9 years). The success rate was low both in the group that was not measured and in the group with SBP above the target goal at the latest visit to the GP (Table 2).

Table 2. Patients reported the last blood pressure (BP) measured to be ≥ 140 mmHg or < 140 mmHg, or they did not answer or did not know the answer.

	BP at re-examination
	≥ 140 mmHg (n = 64)	< 140 mmHg (n = 53)
< 140 mmHg at the last visit to general practitioner	24	32
≥ 140 mmHg at the last visit to general practitioner	19	6
Not known or no answer	21	15

Chi-squared p = 0.02.

The patients were asked to report whether the examining physician was satisfied with the last BP measured in primary care. In total, 55 (47%) of the patients reported that the measured BP was regarded as satisfactory. The success rate was low in the group that reported that the physician not satisfied and in the group that did not know the answer or had no follow-up visit (Table 3).

Table 3. Patients reported the last blood pressure (BP) measured to be satisfactory to the physician or unsatisfactory, or they did not answer or did not know the answer.

	BP at re-examination
	≥ 140 mmHg (n = 64)	< 140 mmHg (n = 53)
Satisfied	24	31
Not satisfied	13	4
Not known or no answer	27	18

Chi-squared p = 0.04.

Only 35 of the patients accepted the 24 h BP measurement.

Discussion

The percentage of pharmacologically treated hypertensives below the target goal declined from 95% to 45.2% after a median observation period of 3.2 years (range 3 months–7.9 years). The large fall in the number of well-controlled hypertensives signifies that the transition from a specialized nurse-led hypertension clinic to control in primary care is a barrier to continuous hypertension control in a group of difficult-to-treat hypertensives. However, the percentage of well-controlled patients in the present study is high compared to recent Danish data showing a control rate of 26–29%.[4,15] Some countries have set up goals for hypertension control. Based on weak, but steady improvements, the US Department of Health and Human Services launched Healthy People 2010, with a goal of 50% for hypertension control rate, along with goals for decreasing hypertension prevalence, lowering salt intake and improving awareness among patients with hypertension.[16] Except for prioritizing hypertension control, the US Department of Health gave no directives as to how the goals are to be reached. However, identifying barriers to and factors acting against hypertension control is an obvious first step. The factors and barriers are usually subdivided into issues related to the patients’ low adherence to treatment, the physicians’ inertia and deficiencies in the healthcare systems.

Theoretically, BP may increase during the study period for at least two reasons: first, SBP increases with increasing age, and there may be a need to increase the hypertension treatment;[9] and secondly, patients may eventually forget about BP and the importance of hypertension control, and BP may increase owing to progressive non-adherence to treatment.

However, there was no sign of BP or hypertension treatment increasing with the length of observation time. The lack of association between SBP and observation time may indicate that some patients continue to be successfully treated and some drop out of control immediately after completing the sessions at the hypertension clinic. The dropout problem has been discussed by other authors.[17] The present paper shows that an important barrier to successful hypertension treatment is a lack of continued systematic control. About 31% of the patients were not controlled at all. It is not known how many patients have no follow-up on a national or global scale, but the high percentage in the present study may reflect a similar percentage on a national scale. The lack of systematic control has been discussed by other authors, but as yet without solutions.[18,19]

No lifestyle or patient-related factors, such as age, gender or BMI, predicted the outcome of this study with high-risk patients. Other authors have reported a tendency towards a worse outcome in patients with many risk factors,[8,20] differences between the two genders [21] and a trend with increasing age.[4] The non-concordance may be explained by the fact that the present study includes only high-risk patients, whereas other studies covered a broad scale of risks in hypertensives.[8,20]

Primary-care physicians are well educated, but some authors claim that physician behaviour – “doctor’s inertia” – is the major cause of poor hypertension control.[22] That statement is supported by the present result showing that many patients had BP values above the target without appropriate action being taken (Table 2).

In the hypertension clinic, nurses and patients were focused on the treatment goals, in close collaboration. In the present study, the two questions: “Was your physician satisfied with the measured blood pressure?” and “Was the last measured systolic blood pressure below 140 mmHg?” were used as indicators for the interaction between physicians and patients. The results showed that a large proportion had no BP measurements or did not collaborate with a health professional in BP control. Thus, the present results show that a continued shared commitment between health professionals and patients in the pursuit of target BP is of the utmost importance. Our finding is in line with other results pointing out that patient knowledge, awareness and self-management behaviour affect hypertension control.[8,23–25]

Two different measurement methods were used in this study. The use of ambulatory BP measurement has its limitations [15] and the patients in this study demonstrated that there were barriers to its use in practice. The method, as it is used today, may be too inconvenient and/or too time consuming for the patients’ repeated use.

Study limitations

There was a very high degree of quality in measurement technique, notwithstanding the possibility of misclassification when patients are evaluated on a dichotomous scale and their BP is close to the cut-off value at 140 mmHg. This problem is caused by BP variability.

The sample size is limited. The small number of patients was compensated for by a very careful measurement technique. The phenomenon of regression towards the mean should be considered, as there were two measurements for each patient.

Conclusion

The transition from control in a hypertension clinic to control in primary care reduces continuous hypertension control as a result of at least two important issues: (i) there is a lack of systematic control; and (ii) the very important shared commitment between health personnel and patients in the pursuit of target BP is discontinued.

What is known about this topic

Most patients who start antihypertensive treatment in hypertension clinics are discharged to further control in primary care when they reach their target value.

Epidemiological surveys show that many hypertensive patients are not treated to the target value.

What this study adds

The well-controlled proportion of the population declined from 95% to 45.3% after a median observation time of 3.2 years after discharge from a hypertension clinic.

Many patients had no control measurement of BP in the observation time.

The transition from a hypertension clinic to control in primary care puts an end to a very dedicated commitment between the health professionals and the patients towards the target goal.

Disclosure statement

No potential conflict of interest was reported by the authors.