
==== Front
Singapore Med J
Singapore Med J
SMJ
Singapore Med J
Singapore Medical Journal
0037-5675
2737-5935
Wolters Kluwer - Medknow India

34717303
SMJ-65-459
10.11622/smedj.2021181
Short Communication
Assessment and stratification of self-care profile of patients with essential hypertension
Wee Yi-Mei Sabrina MMed, FCFPS 12
Koh Yi Ling Eileen BSc 1
Tan Ngiap Chuan MMed, FCFPS 12
1 SingHealth Polyclinics, Singapore
2 SingHealth-Duke NUS Family Medicine Academic Clinical Programme, Singapore
Correspondence: Dr. Yi-Mei Sabrina Wee, Associate Consultant, SingHealth Polyclinics, 167 Jalan Bukit Merah, Connection One Tower 5, #15-10, 150167, Singapore. E-mail: sabrina.wee@singhealth.com.sg
8 2024
31 10 2021
65 8 459465
10 11 2019
30 8 2020
Copyright: © 2024 Singapore Medical Journal
2024
https://creativecommons.org/licenses/by-nc-sa/4.0/ This is an open access journal, and articles are distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 License, which allows others to remix, tweak, and build upon the work non-commercially, as long as appropriate credit is given and the new creations are licensed under the identical terms.
==== Body
pmcINTRODUCTION

Essential hypertension (EH) is prevalent in adults.[1] Optimising blood pressure (BP) control is associated with good health outcomes but requires regular multifaceted management.[2] The 7th Report of the Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure (JNC) recommends that patients with EH engage in the following self-care activities: medication adherence, weight reduction, Dietary Approaches to Stop Hypertension (DASH) diet, regular BP monitoring and physical activity (PA), moderate alcohol consumption and smoking cessation.[3] Commitment to these tasks requires motivation and behaviour change, and can be challenging for many individuals.

Adherence to self-care measures has been shown to result in improvement in outcomes of chronic diseases such as asthma, diabetes mellitus and arthritis.[4] The capability to adhere to self-care measures is reflected in self-efficacy or the belief in one’s ability to succeed in tasks. The level of self-efficacy can determine the ability, capacity and sustainability of efforts to modify one’s behaviour to reach a goal.[5] For patients with chronic conditions like EH, adherence to regular self-care measures is, therefore, influenced by motivation and behaviour adjustments. Assessing the self-care profile of patients with EH is essential to understand their level of self-efficacy, motivation and behaviour modifications in controlling their BP. This assessment can be conducted using questionnaire-based instruments.[6]

In Singapore, the prevalence of EH in Asian adults was 23.5% in 2010.[7] Essential hypertension was the second most common reason for attendances at the local polyclinics in 2016.[8] We postulated that these patients had variable self-care profiles, which were influenced by their demographic factors, self-efficacy, motivation and behaviour change. Our study aimed to determine the self-care profile of community-dwelling patients with EH, such as demographic factors, key self-care measures and BP control. The evaluation of patients’ self-care profile will enable us to identify those with lower self-care profile, whose deficiencies in their self-care behaviour can potentially be mitigated by targeted interventions.

METHODS

This was a cross-sectional study conducted in SingHealth Polyclinics-Bukit Merah, serving a population of 152,790 residents in the southern region of Singapore.[9] The study included patients aged ≥40 years who were diagnosed with EH and were on regular reviews by a doctor or nurse every 3–6 months at the study site. Patients were excluded if they were aged <40 years, had secondary causes of hypertension or disabilities that rendered them incapable of providing written consent. The study was approved by SingHealth Centralised Institutional Review Board (reference number: 2017/2197).

With no prior literature on self-care profile of local patients with EH, the value of 0.5 was adopted as the proportion of patients with low self-care profile to compute a maximum sample size. To ensure that the 95% confidence interval estimate of the proportion of patients with higher level of self-care profile would be within 5% of the true proportion, a sample size of 385 was needed, with inflation to 450 to account for 15% possible variance.

The study questionnaire collated data on socio-demography, body mass index (BMI), BP, diet, self-care activities, scores from the International Physical Activity Questionnaire[10] (IPAQ) to determine the intensity of PA, the five-item Medication Adherence Report Scale to assess medication adherence, and the Hypertension Self-Care Profile (HTN-SCP).[11]

The HTN-SCP is a locally validated disease-specific instrument that assesses three domains — Behaviour, Motivation and Self-efficacy — in the self-care profile of a patient with EH.[11121314] It reviews the patient’s perceptions, willingness and confidence in adhering to a self-care activity to achieve optimal BP control.

From April 2017 to June 2017, potential participants were screened and recruited at the waiting area outside the consultation rooms. They were provided information on the study and given time for clarification before giving informed consent. Upon enrolment, the participant was assisted by the investigator through the questionnaire. Each study participant received a SGD 5 supermarket voucher upon completion of the questionnaire.

The total HTN-SCP scores for each patient were computed using the sum of 60 items in the HTN-SCP instrument. Descriptive statistics were performed and reported as median (interquartile range) and percentages. Univariate analyses were conducted to determine the associations between continuous HTN-SCP scores and the outcomes (medication adherence, IPAQ, BP and dietary habits) using Mann–Whitney U, Kruskal–Wallis and Spearman’s correlation tests. The scores were also analysed in their three domains: Behaviour, Motivation and Self-efficacy. All factors in the univariable analysis with P ≤0.1 were included in multivariable linear regression for each score. A P value of <0.05 was considered statistically significant. All data analyses were conducted using IBM SPSS Statistics version 24.0 (IBM Corp, Armonk, NY, USA).

RESULTS

A total of 450 patients were recruited. Of these, 20 patients did not fit the eligibility criteria, two had duplicate data and seven had incomplete data. The remaining 421 patients were included in the analysis.

Table 1 presents the associations between the demographic and self-care profiles of the study population: 53% of the patients were aged <65 years, 70.6% were Chinese, 37.3% had up to primary education, 67% were married and half of the patients lived in a rental or small–medium-sized apartment. The majority (77.2%) were overweight (BMI >23 kg/m2).[15] Higher HTN-SCP scores were associated with minority ethnic groups, education, alcohol abstinence, moderate-to-high level of PA, medication adherence, regular monitoring of weight and home BP [Table 1]. On dividing the HTN-SCP scores arbitrarily into tertiles, 65.1% of the patients were found to have a high self-care profile.

Table 1 Self-care scores and their association with demographics.

Variable	n (%)	HTN-SCP scoresa	P	Behavioura	P	Motivationa	P	Self-efficacya	P	
Overall	421 (100.0)	192 (172–212.5)	–	59 (52–65)		68 (60–76)		65 (58–74)		
	
Age (yr)			0.237		0.026		0.886		0.178	
	
 ≥65	198 (47)	194 (172–214)		60 (53–66)		69 (60–76.3)		66 (58–74.3)		
	
 <65	223 (53)	190 (171–211)		58 (51–63)		68 (60–76)		65 (57–73)		
	
Gender			0.208		0.249		0.125		0.398	
	
 Male	208 (49.4)	189.5 (170–211.8)		59 (51–64.8)		67 (60–75)		65 (56–74)		
	
 Female	213 (50.6)	194 (175.5–213)		59 (53–65)		69 (61–77)		65 (59–74)		
	
Ethnic group			0.017		0.076		0.010		0.015	
	
 Chinese	293 (70.6)	188 (170–208.5)		58 (51–64.5)		67 (60–75)		64 (57–71)		
	
 Malay/Indian/others	122 (29.4)	200 (173–216.3)		61 (53.8–65)		71 (62–78)		68 (59.8–75.3)		
	
Body mass index (kg/m2)			0.701		0.316		0.638		0.630	
	
 <23	95 (22.8)	190 (172–213)		59 (53–65)		67 (60–76)		65 (59–74)		
	
 ≥23	322 (77.2)	192 (171–212)		59 (51–64)		69 (60–76)		65 (56.8–74)		
	
Education			<0.001		0.002		<0.001		<0.001	
	
 No formal education/primary	157 (37.3)	180 (165.5–202.5)		56 (50.5–62)		64 (57–72)		61 (54–70)		
	
 Secondary	170 (40.4)	199.5 (176.8–216)		60.5 (53–65)		72 (63–78)		67 (60–75)		
	
 Pre-U/diploma/university	94 (22.3)	193 (178.8–216.3)		60 (52.8–66.3)		71 (60.8–77)		67 (59–74)		
	
Employment status			0.128		0.026		0.702		0.009	
	
 Employed	209 (49.9)	190 (172–210)		58 (51–63.5)		69 (61.5–75.5)		64 (56–71.5)		
	
 Unemployed	210 (50.1)	194 (171.8–214)		59.5 (53–66)		67 (60–77)		68 (59–74)		
	
Marital status			0.312		0.120		0.654		0.409	
	
 Married	282 (67)	194 (172–213)		59 (53–65)		69 (60–76)		66 (57.8–74)		
	
 Single/divorced/separated/widowed	139 (33)	190 (169–210)		57 (50–65)		68 (60–76)		64 (58–72)		
	
Housing type			0.189		0.099		0.183		0.440	
	
 Rental apartment/small to medium public apartment	211 (50.1)	191 (168–211)		58 (51–64)		67 (59–75)		65 (56–74)		
	
 Large public apartment	184 (43.7)	194 (176–213.8)		60 (53–66)		70 (60.3–77)		66 (58–74)		
	
 Private/landed house	26 (6.2)	196 (177.8–210)		59 (52.5–63.3)		71 (59.8–78.3)		65.5 (62.5–71.3)		
	
Current smoker			0.064		0.003		0.369		0.152	
	
 Yes	50 (11.9)	185 (156.8–210.3)		54 (47–62.3)		66 (58.8–75.3)		63 (50–74)		
	
 No	370 (88.1)	193 (172.8–213)		59 (53–65)		69 (60–76)		65 (58–74)		
	
Consume alcohol			0.032		0.009		0.208		0.054	
	
 Yes	54 (12.8)	184 (171.8–199.5)		56 (49.8–61.3)		66 (61–74)		63.5 (55–68.3)		
	
 No	367 (87.2)	194 (172–214)		59 (53–65)		69 (60–77)		66 (58–74)		
	
Consume alcohol			0.099		0.031		0.450		0.143	
	
 >7 units per week	12 (2.9)	186 (172–206.5)		55.5 (49.3–64.3)		66 (58.8–73.8)		65.5 (58–70.3)		
	
 Social drinker	42 (10.0)	184 (171–199.5)		56 (49.5–61)		66 (61.8–74.3)		63 (54.8–68.3)		
	
 Non-drinker	367 (87.2)	194 (172–214)		59 (53–65)		69 (60–77)		66 (58–74)		
	
IPAQ categorical score			0.003		0.078		<0.001		0.015	
	
 Low	71 (17.3)	180 (163–203)		56 (51–63)		63 (57–69)		61 (55–70)		
	
 Moderate/high	339 (82.7)	195 (175–213)		59 (53–65)		70 (61–77)		66 (59–74)		
	
Medication adherenceb			0.009		0.005		0.030		0.018	
	
 Poor adherence	194 (46.9)	188.5 (170–209)		58 (50–63)		67 (60–75)		64 (56–71.3)		
	
 Adherence	220 (53.1)	195.5 (173–216.8)		59 (53–66)		69 (60.3–78)		66 (59–75)		
	
Monitor your weight regularly			<0.001		<0.001		0.034		0.001	
	
 Yes	157 (37.3)	199 (177–218)		61 (55.5–67)		72 (61–77)		68 (59–75)		
	
 No	264 (62.7)	188 (168–208.8)		58 (50–63)		67 (60–75)		64 (56–71)		
	
Use of blood pressure (BP) machine at home			0.002		<0.001		0.036		0.028	
	
 Yes	220 (52.3)	196 (176–217)		61 (54–67)		70 (60–77)		66 (58–74)		
	
 No	201 (47.7)	188 (168–208.5)		57 (49.5–62)		66 (60–74.5)		65 (56–72.5)		
	
Frequency of recording your BP			0.009		<0.001		0.029		0.123	
	
 None	201 (47.7)	188 (168–208.5)		57 (49.5–62)		66 (60–74.5)		65 (56–72.5)		
	
 Regular (at least once a day)	150 (35.6)	196 (175–217.3)		61 (54.8–67)		68.5 (60–77)		66 (58–74.3)		
	
 Often (at least once a week)	58 (13.8)	199 (177.8–219.3)		62 (53–67)		74 (63–78)		67.5 (60–74.8)		
	
 Seldom (at least once a month)	12 (2.9)	194.5 (166.5–202.8)		57.5 (52.3–61.3)		69.5 (58.3–75.3)		66 (55.8–70)		
	
BP controlc			0.906		0.663		0.786		0.762	
	
 Not well controlled	107 (25.4)	192 (169–213)		59 (51–65)		69 (60–76)		65 (56–74)		
	
 Well controlled	314 (74.6)	192.5 (172–212)		59 (52.8–65)		68 (60–76)		65 (58–74)		
	
Mean SBP	132.8 (15)	–	–	–	–	–	–	–	–	
	
Mean DBP	69.2 (9.6)	–	–	–	–	–	–	–	–	
	
Median SBP	131 (124–140)	–	–	–	–	–	–	–	–	
	
Median DBP	68 (62–76)	–	–	–	–	–	–	–	–	
	
Levels of self-care behaviour										
	
 Low/medium (60–<180)	147 (34.9)	–	–	–	–	–	–	–	–	
	
 High (180–<240)	274 (65.1)	–	–	–	–	–	–	–	–	
aData presented as median (interquartile range). bPoor medication adherence based on five-item Medication Adherence Report Scale (MARS-5) score <25. cAccording to Ministry of Health, Singapore. MOH clinical practice guidelines 1/2017. Available from: https://www.moh.gov.sg/docs/librariesprovider4/guidelines/cpg_hypertension-booklet---nov-2017.pdf. [Last accessed on 2018 Aug 09]. HTN-SCT: Hypertension Self-Care Profile, IPAQ: International Physical Activity Questionnaire

Regarding the respective domains, higher median scores in the Behaviour domain were associated with older age group (≥65 years), higher education, unemployment, non-smoking, lower quantum of alcohol intake, medication adherence, and frequent home BP and weight monitoring. Minority ethnicity, higher education, moderate/high PA, regular weight monitoring and medication adherence were associated with higher median scores in the “Self-efficacy” and “Motivation” domains. Unemployment and frequent home BP monitoring were separately associated with higher score in the “Self-efficacy” and “Motivation” domains, respectively.

Awareness of healthy diet, willingness to modify diet to control BP and avoidance of food perceived to be bad for BP were associated with higher HTN-SCP scores [see Supplemental Digital Appendix]. Table 2 shows the association between HTN-SCP scores and levels of education, PA (IPAQ scores), willingness to modify diet to control BP and weight, selection of low-salt products and healthier food options using linear regression analysis. Higher HTN-SCP scores were associated with lower BMI and median systolic BP (SBP) and diastolic BP (DBP) as compared to medium and lower HTN-SCP scores [Table 3].

Table 2 Factors associating HTN-SCP scores using linear regression.

Factor	Beta (95% CI)	P	
Ethnic group			
	
 Chinese	Reference	–	
	
 Malay/Indian/others	2 (–3.1 to 7.1)	0.434	
	
Education			
	
 Pre-U/diploma/university	Reference	–	
	
 No formal education/primary	–6.5 (–12.6 to –0.4)	0.036	
	
 Secondary	1.9 (–3.9 to 7.8)	0.518	
	
Current smoker			
	
 No	Reference	–	
	
 Yes	3 (–4.1 to 10.1)	0.409	
	
Consume alcohol			
	
 Yes	Reference	–	
	
 No	5.6 (–1 to 12.1)	0.094	
	
IPAQ categorical score			
	
 Moderate/high	Reference	–	
	
 Low	–7.3 (–13.1 to –1.5)	0.014	
	
Medication adherence			
	
 Poor adherence	Reference	–	
	
 Adherence	2.4 (–1.9 to 6.8)	0.274	
	
Monitor weight regularly			
	
 No	Reference	–	
	
 Yes	1.1 (–3.6 to 5.8)	0.655	
	
Use BP machine at home			
	
 No	Reference	–	
	
 Yes	2.6 (–2 to 7.2)	0.271	
	
Perception of healthy diet			
	
Do you know how your diet should be like?			
	
 No	Reference	–	
	
 Yes	0.8 (–5.7 to 7.3)	0.812	
	
I am willing to change my diet to control my BP.			
	
 No/not sure	Reference	–	
	
 Yes	7.2 (1.1 to 13.3)	0.021	
	
I avoid food that I know is bad for my BP.			
	
 No/not sure	Reference	–	
	
 Yes	5.1 (–2.4 to 12.6)	0.182	
	
Modification of dietary habit			
	
Do you manage your diet to try to keep your weight at an optimal level?			
	
 No	Reference	–	
	
 Yes	13.6 (8.8 to 18.5)	<0.001	
	
Do you actively ask for less salt in your meals?			
	
 No	Reference	–	
	
 Yes	1.2 (–3.5 to 5.9)	0.607	
	
I take supper frequently.			
	
 No	Reference	–	
	
 Yes	–0.4 (–5.9 to 5)	0.873	
	
Choice of food option			
	
Do you choose baked, steamed or grilled options when available rather than fried foods?			
	
 No	Reference	–	
	
 Yes	2.6 (–1.9 to 7.1)	0.265	
	
Do you regularly eat processed meats such as ham, bacon or smoked/salted fish?			
	
 No	Reference	–	
	
 Yes	–5.5 (–13.5 to 2.4)	0.169	
	
Are you likely to choose a product that has low sodium content on the label?			
	
 No	Reference	–	
	
 Yes	12.2 (7.3 to 17)	<0.001	
	
Do you actively choose a healthier option when you eat?			
	
 No/not sure	Reference	–	
	
 Yes	16.8 (8.9 to 24.7)	<0.001	
BP: blood pressure, CI: confidence interval, HTN-SCT: Hypertension Self-Care Profile, IPAQ: International Physical Activity Questionnaire

Table 3 Association of body mass index and blood pressure with subgroup of scores.

Variable	Median (IQR)/n (%)	P	
	
Low score (60–<120)	Medium score (120–<180)	High score (180–<240)	
Body mass index (kg/m2)	32.8 (31.7–34.3)	26.1 (23.1–28.9)	27 (23.6–29.6)	0.005	
	
SBP (mm Hg)	144 (138.5–158)	129 (120.5–139)	132 (124–140)	0.010	
	
DBP (mm Hg)	84 (74–93.5)	66 (61–76.5)	68 (62–76)	0.018	
	
Ethnic group				0.077	
	
 Chinese	2 (0.7)	108 (36.9)	183 (62.5)		
	
 Malay/Indian/Others	3 (2.5)	34 (27.9)	85 (69.7)		
DBP: diastolic blood pressure, IQR: interquartile range, SBP: systolic blood pressure

DISCUSSION

The study revealed self-care profiles in a multiethnic Asian population with EH. Higher HTN-SCP scores were associated with home BP monitoring [Table 1]. Glynn et al.[16] reported that self-monitoring of BP was associated with a moderate reduction of SBP and DBP. Our results revealed that patients with higher HTN-SCP scores had lower median SBP and DBP [Table 3] and were more likely to attain the goal of hypertension treatment.

Those with higher level of education seemed to have higher self-care profile. Better educated patients have better access to health-related information, which can raise their level of awareness of relevant self-care measures to support their BP control.[17] In contrast, there was no association between length of education (cut-off at 6 years) and self-care behaviour in a study on rural Chinese patients with EH in China.[18] The urban setting and multiethnicity of the population, and the curriculum and quality of education could have contributed to the difference in educational background of the two study populations.

Health literacy alone is unlikely to significantly transform self-care behaviour. The awareness of health-promoting measures in Iranian patients with EH did not translate to better lifestyle behaviour.[19] Self-care is influenced by beliefs, motivation and self-efficacy, which underpin the architecture of the HTN-SCP instrument used in this study. This provides a conceptual framework to assess the willingness, confidence and practice of self-care measures by patients with EH.

The HTN-SCP scores stratify the study population based on their execution of self-care measures. Higher HTN-SCP scores were associated with alcohol abstinence, moderate-to-high level of PA, medication adherence, not smoking and proactive dietary measures to control weight and BP. This is reflected in the dietary control and monitoring of weight at home.

Dividing the HTN-SCP scores into tertiles revealed that about one-third (34.9%) of the study population was stratified into low-to-moderate self-care profile categories. The scores seemed to be able to discriminate the JNC-recommended self-care measures for patients with EH. This provides an opportunity to identify deficiencies in self-care behaviour, which may potentially be mitigated by targeted interventions.

The study has several strengths. The HTN-SCP scores showed significant correlations with key self-management measures and BP measurements. It is a feasible method to provide healthcare providers with insight into the key constructs of self-care profile of their patients with EH. It also provides a potential platform for comparison of self-care profiles across different populations.

The results allude to a more efficient utility of healthcare resources in managing patients with EH. The self-care profile can be used to develop personalised care plan based on patients’ behaviour. Those with high self-care profile can be co-managed with other professionals such as nurse practitioners or via telehealth consultations, in between face-to-face reviews by physicians. This approach frees up physician time and resources to manage and motivate patients with lower self-care profile. A multidisciplinary care team can work together to raise patients’ level of self-efficacy and self-care capacity. The HTN-SCP scores can potentially be used by the healthcare team to reassess the progress of their self-care profiles.

There are several limitations in this study. Random sampling would have averted selection bias of potential subjects, but implementation was not feasible due to the large number of daily attendances at the study site. Self-reporting of medication adherence and levels of PA using instruments is subjected to recall bias, but alternative data capture was unavailable to the investigators. The HTN-SCP tool was also not designed to cater to ethnicity-related differences in self-care profile of the study population. Finally, the DASH diet adapted for Asians has yet to be validated in the local setting.

Financial support and sponsorship

The study was supported by seed funding from the SHP Research Support Programme (SHP-SEED39-2016[8]).

Conflicts of interest

There are no conflicts of interest.

Supplemental digital content

Appendix at http://links.lww.com/SGMJ/A129

Acknowledgement

We would like to thank the nursing students from Ngee Ann Polytechnic, Singapore, the staff and patients from SingHealth Polyclinics (SHP)-Bukit Merah who contributed to the study, and the research department at SHP for their invaluable help.

APPENDIX

Association between HTNSCP scores and dietary habits

Diet	Total HTNSCP Score, Median (IQR)	P- value	Behaviour, Median (IQR)	P- value	Motivation, Median (IQR)	P- value	Self-efficacy, Median (IQR)	P- value	
Perception of healthy diet								
Awareness of healthy diet	<0.001		0.002		<0.001		<0.001	
Yes	195 (176-214)		59 (53-65)		69 (61-77)		66 (59-74)		
No	177 (158.3- 193.8)		54 (49.8-61.3)		62 (56-71)		59 (52.8-67)		
I am willing to change my diet to control my blood pressure	<0.001		<0.001		<0.001		<0.001	
Yes	195 (176-214)		60 (53-65)		70 (62-77)		66 (59-74)		
No/ Not Sure	176 (150-196.8)		53 (46.3-60)		60.5 (52-71)		59 (50-68)		
I avoid food that I know is bad for my blood pressure	<0.001		<0.001		<0.001		<0.001	
Yes	197 (177-214)		60 (54-65.3)		71 (62-77)		67 (59-75)		
No/ Not Sure	166 (145-183)		49 (46-55)		60 (50-68)		54 (48-64)		
Modification of dietary habit								
Do you keep a food diary?	0.163		0.093		0.173		0.208	
Yes	206 (174.5- 230.3)		64.5 (52-72.3)		72 (63.8-78.5)		68.5 (61.3-79.3)		
No	192 (171.8- 212.3)		59 (52-65)		68 (60-76)		65 (58-74)		
Do you manage your diet to try to keep your weight at an optimal level?	<0.001		<0.001		<0.001		<0.001	
Yes	200 (180-218)		61 (55-66)		72 (63-78)		68 (60-76)		
No	176 (155.5-197)		54 (48-60.5)		63 (56-71)		60 (51.5-66.5)		
Do you regularly eat prepacked meals? For example, ready meals or canned	0.213		0.484		0.506		0.043	
soups								
Yes	183.5 (162.3- 213.8)		56.5 (50.3-65)		64.5 (60-78.8)		61.5 (52.3-71.8)		
No	194 (172-212)		59 (52.5-65)		69 (60-76)		66 (58-74)		
Do you skip meals frequently?	0.486		0.009		0.504		0.737	
Yes	191 (172-209.5)		57 (50-63)		71 (61.5-75.5)		65 (59-72.5)		
No	194 (171-213.8)		60 (53-65)		67 (60-77)		65 (57-74)		
Do you actively ask for less salt in your meals?	<0.001		<0.001		0.007		<0.001	
Yes	199 (177-220)		61.5 (54.3-67)		70 (62-77)		67 (60-76)		
No	188 (166-208)		57 (50-62)		67 (59-75)		64 (55-70)		
Do You Snack?		0.958		0.293		0.242		0.856	
Yes	194 (173.5-211)		59 (51-64)		70 (62-75.5)		65 (59-73)		
No	188 (171-216.8)		59 (53-66.8)		65.5 (60-76.8)		65 (56-74)		
I take supper frequently	0.025		0.001		0.238		0.034	
No	194 (173-213)		60 (53-65)		69 (60-76)		66 (58.8-74)		
Yes	185 (164-203)		55 (48-62)		68 (58-75)		63 (53-71)		
Choice of food option								
Do you choose baked, steamed or								
grilled options when available rather	0.036		0.869		0.001		0.034	
than fried foods?									
Yes	194.5 (177-213)		59 (53-65)		71 (63-77)		66 (59-74)		
No	188 (168-211)		59 (51-65)		65 (59-75)		64 (55.5-73)		
Do you base your main meals around								
starchy food? For example, potatoes, pasta, rice or bread	0.819		0.706		0.833		0.744	
Yes	192.5 (172- 212.8)		59 (53-65)		69 (60-76)		65 (58-74)		
No	191 (175-213)		59 (51-65)		67 (61-76)		66 (59-73)		
Do you regularly include legumes in your diet? For example, beans and lentils	0.139		0.055		0.276		0.182	
Yes	194 (175-214)		59 (54-65)		68.5 (61-77)		66 (59-74)		
No	190 (168-210)		58 (50.5-64)		68 (60-75.5)		65 (56-73)		
Do you regularly eat processed meats such as ham, bacon or smoked/salted fish	0.008		0.034		0.099		0.001	
Yes	178 (160-188)		54 (48-62)		65 (60-70)		59 (52-66)		
No	194 (172-213)		59 (53-65)		69 (60-76)		66 (58-74)		
Are you likely to choose a product that has low sodium content on the label?	<0.001		<0.001		<0.001		<0.001	
Yes	202 (180-220)		62 (57-68)		72 (63-78)		69 (62-76)		
No	180 (160-196)		54 (48-60)		64 (56-73)		60 (53-68)		
Do you actively choose a healthier option when you eat?	<0.001		<0.001		<0.001		<0.001	
Yes	196 (177-214)		60 (54-65)		71 (62-77)		66 (60-75)		
No/ Not Sure	156 (143-179)		49 (44-54)		56 (50-64)		53 (46-61)
==== Refs
REFERENCES

1 World Health Organization. Global status report on non-communicable diseases 2014 Available from: http://apps.who.int/iris/bitstream/handle/10665/148114/9789241564854_eng.pdf;jsessionid=AD71DCEF5FE7AB3C4200853356D07D95?sequence=1 [Last accessed on 2018 Aug 09]
2 World Health Organization. A global brief on hypertension Available from: http://apps.who.int/iris/bitstream/handle/10665/79059/WHO_DCO_WHD_2013.2_eng.pdf?sequence=1 [Last accessed on 2018 Aug 09]
3 Chobanian AV Bakris GL Black HR Cushman WC Green LA Izzo JL Jr The seventh report of the Joint National Committee on prevention, detection, evaluation, and treatment of high blood pressure: The JNC 7 report JAMA 2003 289 2560 72 12748199
4 Bodenheimer T Lorig K Holman H Grumbach K Patient self-management of chronic disease in primary care JAMA 2002 288 2469 75 12435261
5 Bandura A Self-efficacy: Toward a unifying theory of behavioural change Psychol Rev 1977 84 191 215 847061
6 Lua YH Hong LY Bong HS Yeo JLS Tsang MLP Ong KZ A narrative review of the evaluations and selection of instruments which assess self-efficacy amongst patients with essential hypertension Proc Singapore Healthc 2016 25 98 104
7 Chua LAV National Health Survey 2010 Statistics Singapore Newsletter, March 2010 Available from: https://www.singstat.gov.sg/-/media/files/publications/society/ssnmar10-pg25-27.pdf [Last accessed on 2018 Aug 09]
8 Ministry of Health, Singapore. Top 4 conditions of polyclinic attendances Available from: https://www.moh.gov.sg/resources-statistics/singapore-health-facts/top-4-conditions-of-polyclinic-attendances [Last accessed on 2018 Aug 09]
9 Department of Statistics, Singapore. Population Trends 2017 Available from: https://www.singstat.gov.sg/-/media/files/publications/population/population2017.pdf [Last accessed on 2018 Aug 09]
10 Craig CL Marshall AL Sjöström M Bauman AE Booth ML Ainsworth BE International physical activity questionnaire: 12-country reliability and validity Med Sci Sports Exerc 2003 35 1381 95 12900694
11 Koh YL Lua YH Hong L Bong HSS Yeo LSJ Tsang LPM Using a web-based approach to assess test-retest reliability of the “hypertension self-care profile” tool in an Asian population: A validation study Medicine (Baltimore) 2016 95 e2955 26945410
12 Han HR Lee H Commodore-Mensah Y Kim M Development and validation of the hypertension self-care profile: A practical tool to measure hypertension self-care J Cardiovasc Nurs 2014 29 E11 20 24088621
13 Seow KC Yusoff DM Koh YLE Tan NC What is the test-retest reliability of the Malay version of the Hypertension Self-Care Profile self-efficacy assessment tool? A validation study in primary care BMJ Open 2017 7 e016152
14 Ngoh SHA Lim WLH Koh YLE Tan NC Test–retest reliability of the Mandarin versions of the Hypertension Self-Care Profile instrument Medicine (Baltimore) 2017 96 e8568 29137076
15 WHO Expert Consultation Appropriate body-mass index for Asian populations and its implications for policy and intervention strategies Lancet 2004 363 157 63 14726171
16 Glynn LG Murphy AW Smith SM Schroeder K Fahey T Interventions used to improve control of blood pressure in patients with hypertension Cochrane Database Syst Rev 2010 CD005182. doi: 10.1002/14651858. CD005182.pub4
17 Di Chiara Scaglione A Corrao S Argano C Pinto A Scaglione R Association between low education and higher global cardiovascular risk J Clin Hypertens (Greenwich) 2015 17 332 7 25703272
18 Hu H Li G Arao T Prevalence rates of self-care behaviours and related factors in a rural hypertension population: A questionnaire survey Int J Hypertens 2013 2013 526949
19 Akbarpour S Khalili D Zeraati H Mansournia MA Ramezankhani A Fotouhi A Healthy lifestyle behaviors and control of hypertension among adult hypertensive patients Sci Rep 2018 8 8508 29855520
