SLEEP DEFICIENCY AS A RISK FACTOR FOR HYPERTENSION: A SYSTEMATIC REVIEW

Abdelrahman Mohamed Ahmed Abukanna^1*, Basil Falah Ayed Alanazi², Sulaiman Turki Arfaj Alanazi², Essa Abdulrhman Mater ALHarbi³, Thamer Mohammed Matrud Alanazi⁴  

ABSTRACT

The importance of sleep to one's physical, mental, and emotional health cannot be overstated. In addition to contributing to neurological and psychological issues, a lack of sleep has also been shown to negatively affect the cardiovascular system, according to research in the literature. Heart disease (CVD) risk factors such as hypertension, obesity, diabetes, and dyslipidemia have been linked to decreased sleep quantity and quality. We searched PubMed, Web of Science, Science Direct, EBSCO, and the Cochrane library. Using Rayyan QCRI, study papers were first screened by title and abstract before a full-text analysis was done. Results: This review covered a total of 8 research, with participants ranging in age and sex. More than half were male. In all included studies, the hypertension prevalence was obtained and then studied concerning sex and age group. Different methods of measuring sleep duration were used in the included studies, but they are all valid. The key finding of the majority of the research under consideration is that adolescents with short sleep duration had elevated blood pressure. Long periods of sleep may be linked to high blood pressure, although the evidence does not make this connection evident.

Keywords: Sleeping, Sleep deprivation, Blood pressure, Short sleep duration, Night sleeping, Hypertension and  hypertensive

Introduction

Despite advancements in knowledge, care, and management of the condition, the prevalence of hypertension has grown during the last ten years [1]. Leading causes of cardiovascular disease, stroke, renal damage, and disability include hypertension [2]. Significant health and financial advantages come from early identification, timely treatment, and improved control of hypertension. There are many risk factors responsible for hypertension in adults and adolescents. These factors include the integration and accumulation of genetic and environmental factors [3].

Some of the current strategies being considered to reduce the risk of hypertension include maintaining a healthy body weight (BMI = 18.5-24.9 kg/m2) and waist circumference (102 cm for men and 88 cm for women), addressing behavioral risk factors like an unhealthy diet, harmful alcohol use, lack of exercise, and smoking, adhering to a diet including more fruit and vegetables, low-fat dairy products, and limiting sodium intake from all sources.

Our lives are essentially one-third taken up by the physiological process of sleep. Due to the accelerated pace of modern life, the average nightly sleep duration has decreased considerably. Sleep deprivation has long been associated with neurocognitive impairment, physical strength, skill attenuation, and increased impaired judgment [4, 5]. However, excessive long sleep may also lead to health injury. Several studies have reported an association between sleep duration and chronic conditions, including type 2 diabetes, obesity, atherosclerosis, and hypertension [6, 7]. Numerous studies have revealed a link between the length of sleep and hypertension. The first research to demonstrate that the relationship between sleep length and hypertension followed a U-shaped curve found that sleep duration of 7 or >8 h was related to an elevated risk of hypertension [8].

The correlation between sleep disturbances and blood pressure readings is significant since high blood pressure may be a cardiovascular risk factor that may be modified. Long-term exposure to brief sleep intervals may contribute to the development and maintaining cardiovascular and vascular effects of hypertension consequences [9]. both heart rate and blood pressure exhibit an everyday trend, with sleep having a low-level reading. With the commencement of sleep, blood pressure progressively drops and then stays low until the waking moment, when it abruptly rises [10]. Therefore, sleeping less each night would result in higher average 24-hour blood pressure and heart rate. prolonged contact with heightened activity of the sympathetic nervous system and awakening pressures both physical and psychological would also follow from shorter sleep lengths. It has been demonstrated that increased stress increases salt intake while decreasing renal salt-fluid excretion. 11 Short sleep durations and increased total 24-hour hemodynamic load over time may cause anatomical changes, including the remodeling of the left ventricle and arteries, that eventually reset the entire circulatory system to function at a raised pressure equilibrium. Through extended exposure to heightened 24-hour blood pressure and heart rate, elevated sympathetic nervous system activity, awake physical and psychological stresses, and increased salt retention, habitually short sleep durations may contribute to the development and maintenance of hypertension. Numerous studies have already demonstrated that, in children, adolescents, and adults, the length of sleep is a significant risk factor for developing hypertension and other cardiometabolic illnesses [11-13]. However, several in-depth investigations using objective sleep measurement techniques, such as polysomnography, found no link between senior people's high blood pressure and their short sleep duration [14-16]. In this systematic review study, we discuss the previously reported relation between hypertension and sleeping duration in previously published studies in the database. 

Objectives

To examine the epidemiological data supporting the link between teenage blood pressure and sleep duration.

Materials and Methods

The established procedures were followed in conducting this systematic review (Preferred Reporting Items for Systematic Reviews and Meta-Analyses, PRISMA).

Study Design

This was a thorough analysis and meta-analysis.

Study Duration

Between July and August of 2022, the study was carried out.

Study Condition

This evaluation examines the published works that have been written about the relationship between short-time sleeping and hypertension among adults and adolescents and how sleeping deprivation can be a major risk factor for hypertension.

Search Strategy

To find the relevant literature, a thorough literature search was done in five main databases, including PubMed, Web of Science, Science Direct, EBSCO, and Cochrane Library. Our search was restricted to the English language, and it was customized as needed for each database. The following keywords, which were converted into Mesh terms in PubMed, were used to identify the appropriate studies; " sleeping, sleep deprivation, blood pressure, short sleep duration, night sleeping, hypertension, and hypertensive." The "OR" and "AND" Boolean operators were combined with the pertinent keywords. English, full-text publications, publicly accessible papers, and human trials were all included in the search results.

Selection Criteria

Studies meeting the following criteria were included in our review:

• Cohort and retrospective cohort studies, as well as research methods that provide qualitative or quantitative information regarding the relation between short-duration sleeping and hypertension.

The following was listed as an exclusion criterion:

• Studies not carried out in English.
• Studies are not available for free.

Data Extraction

To identify the duplicate components of the search strategy results, we employed Rayyan (QCRI) [11]. By filtering the combined search results according to a set of inclusion/exclusion criteria, the researchers assessed the adequacy of the titles and abstracts. The reviewers evaluated each paper's entire text which satisfied the inclusion requirements. The authors engaged ins discussion to settle any disagreements. A form for data extraction was made to include the qualified. The study titles, authors, year, population, participant count, gender, incidence, paralytic ileus risk variables, and main findings were all retrieved by the authors.

Risk of Bias Assessment

To evaluate the caliber of the included research, the qualitative data synthesis employed the ROBINS-I technique for non-randomized studies [17]. Any anomalies in the quality rating were looked into and corrected by the reviewers.

Strategy for Data Synthesis

Summary tables were presented to give a qualitative summary of the included study components and data on the results, including the information gathered from the accepted research. Decisions on the best way to use the data from the included study articles were determined after the systematic review's data extraction process was complete. Studies that complied with the full-text standards but lacked any information on the relationship between sleeping time and hypertension were omitted.

Results and Discussion

Search Results

All in all, 220 research papers were extracted based on a thorough search, and 53 duplicates were eliminated. screening of titles and abstracts was done on 25 studies, 20 of which were eliminated. One hundred and twenty-two Only 30 of the reports that were requested for recovery were unsuccessful. 20 articles were removed due to incorrect research outcomes after 92 papers had been screened for full-text evaluation. 38 were excluded for unavailable data on the incidence of epileptic seizures, and 42 were excluded for the incorrect population. This systematic review contained eight appropriate study papers.  

Characteristics of the Included Studies

All 8 studies were included in this review. The main topic of most of these studies ranged from the relation between sleeping time, sleeping deprivation, short sleeping duration, and hypertension was included among them. Five studies were cross-sectional [16-20], while three were designed longitudinally [21-23]. The studies' samples ranged in size from 2887 to 43 655 people. Different age groups were studied, including the elderly, adults, and adolescents. Three studies were conducted in China [17, 18, 20] and one in the United States [19].

In the Table 1, we included the summary of previous studies with their main objectives, key findings, and the year of publication.

Table 1. Summary of characteristics of the included studies

Research on the association between sleeping patterns and hypertension has helped better understand the occurrence of such a problem. Previously, the lack of a standardized method to report sleep duration presented an obstacle to identifying the actual sleep duration time and quality. Measurement of sleep time is done in this way significantly as the strength of the outcomes because individual assessment of sleep time can be overestimated or underestimated using techniques like self-reporting, parental reporting, questionnaires, or sleep diaries [21, 24]. In contrast, professional Polysomnography, which measures sleep time objectively, is regarded as the gold standard [25]. The gold standard for tracking and identifying sleep disturbances is the polysomnographic study, which is conducted in a lab throughout a full night [26]. Actigraphy was employed in the absence of a polysomnography machine since it is an examination that uses tools comparable to a clock (actigraph) [27]. But a study shows there is enough congruence between self-reported and objective assessments suggesting that studies using only questionnaires are also valid [27, 28].

While all the publications included in this review was done to investigate the relationship between sleeping pattern and hypertension, different location, time, and different samples of adults and adolescents were included. It can be considered a good enough database to report the relationship between the two items. However, differences in methodology make it difficult to draw definitive conclusions.

Previously reported Results of research generally suggested the theory Those teenagers who get little sleep are considerably more likely to have elevated blood pressure [29-31]. The study conducted by Javaheri et al. [32] found that short sleep duration raised the risk of prehypertension by 2.5 times after controlling for sex, body mass index (BMI), and socioeconomic level. In their research, Au et al. [33]. Blood pressure and sleep length were inversely correlated, with a mean decrease in sleep duration of 1 hour being linked with a rise in SBP of 2 mmHg and DBP of 1 mmHg.

The odds ratio (OR) of the grouped data from a different meta-analysis by Jiang et al. [12] showed that short sleep duration was linked to a higher risk of high blood pressure (OR=1.51; 95% confidence interval [95% CI] 1.04-2.19, random effects model), particularly in male adolescents (OR = 1.55; 95% CI 1.24-1.93, random effects model) [12].

Yan Wang, MD. et al. reported in their meta-analysis that not only short sleep duration but also excessive long sleep duration are the main risk factors for hypertension, especially in the female sex [23]. The pooled odds ratios (ORs) for hypertension changed in a U pattern was observed owing to the alteration in sleeping time. Individuals who slept less than five hours compared to those who slept for seven hours had an unadjusted OR for hypertension of 1.61, 95% CI = 1.28-2.02; those who slept more than nine hours compared to those who slept for seven hours had an unadjusted OR of 1.29, 95% CI = 0.97-1.71. After age and gender adjustments, the pooled ORs remained statistically significant. Women who lacked sleep had a greater risk of hypertension than males (OR = 1.30, 95% CI = 0.93-1.83) (sleep time 5 h vs. 7 h, OR = 1.68, 95% CI = 1.39-2.03).

In another study done in northeast China by Meng Li et al. [20], they approved that among those aged 18 to 44, a lack of sleep was substantially linked to hypertension. Hypertension was present in 32.6% of the population overall. In comparison to those who slept 7-8 hours per night, those who slept less than 7 hours a day had a greater risk of hypertension (OR=1.24, 95% CI: 1.05 to 1.46) among participants ages 18 to 44. In the group of middle-aged people (45-59 years) or older adults, there were no connections between sleep duration and hypertension that were statistically significant (60–79 years). These results were in contrast with Southwest China by Jie He and Quan He [18], who reported shows a short sleep duration (6h/day) is associated with a higher risk of hypertension, indicating that sleep aids in preventing hypertension. They stated that 51.2% of people had hypertension overall. Unadjusted analysis revealed that persons with short (6h/day) or long (>8h/day) sleep durations had a greater risk of developing hypertension than those with a normal (6–8 h/day) sleep length. However, compared to participants with a normal sleep duration (6-8 hours per day), the risk of hypertension was significantly higher (by 25%) in those with a short sleep duration (6 hours per day) (OR = 1.25, P = 0.02, 95%CI = 1.036-1.508), but not in those with a long sleep duration (>8 hours per day) (17.5% increase).

Even though it seems that lack of sleep contributes to hypertension, the mechanism(s) at play in this association are not fully known. There are some plausible explanations, and nocturnal sympathetic activity is probably the most important [34]. The vagal system is triggered, and catecholamine production is reduced during a typical sleep cycle [35, 36]. However, studies of serum stress hormones following sleep deprivation suggest that sleep deprivation may serve as a stressor on the organism and activate the sympathetic system [37, 38]. The result is increased central catecholamine synthesis and stimulation of the renin-angiotensin-aldosterone pathway [39, 40]. This causes blood vessels to tighten, raising blood pressure and possibly developing hypertension [41]. Another study found that intracellular magnesium concentrations and flow-mediated arterial dilation were reduced during prolonged sleep deprivation [42].

In another cross-sectional study by Ogugu EG et al. it was reported that sleeping habits strongly affect blood pressure control among their sample. In the subgroup of people using antihypertensive medication, those who slept for less than six hours had a poorer likelihood of maintaining blood pressure control than those who slept for seven to nine hours (OR = 0.53; 95% CI: 0.36–0.77; P = 0.002) [19]. There were no discernible variations in BP control between the reference sleep length group—consisting of those who get seven to nine hours of sleep—and the groups consisting of those who get six to seven or more hours of sleep. regardless of age and sex. These findings add to the data from earlier research that suggests insufficient sleep is a substantial risk factor for hypertension [43, 44]. These results are in line with those of another study, which found that persons who slept for less than 4, 5, or 6 hours per night had an 86%, 56%, and 27% higher risk of hypertension than those who slept for 7 hours or more [45]. For instance, research has shown that limiting sleep to fewer than 5 hours per day can reduce blood pressure in persons with normal blood pressure [46] and hypertension increases the SNS activity significantly and increases BP [47, 48].

Conclusion

According to our study, extremely lengthy and short sleep durations Maybe both contribute to the risk of high blood pressure. and these relationships are more pronounced in women than in males. The participants' daily sleep patterns showed a clear U-shaped change in the pooled odds ratios for hypertension, with 7 hours per day of sleep having the lowest risk. However, regardless of how long they sleep at night, only those who get less than 7 hours of sleep have an increased risk of hypertension

Acknowledgments: Many thanks to dr. Abdelrahman Mohamed Ahmed Abukanna Associate professor of internal medicine, faculty of medicine, Northern Border University, Saudi Arabia, for his continuous help, support and encouragement to complete this work.

Conflict of interest: None

Financial support: None

Ethics statement: None

1.        Buzaalirwa L, Nambala L, Banturaki G, Amor PI, Katahoire A, Geng E, et al. Implementing screening for hypertension in archetypal HIV primary care: a mixed-methods assessment. BMC Health Serv Res. 2022;22(1):1041. doi:10.1186/s12913-022-08362-y

2.        Sheikh MS, Aljohani EM, Alrayes FH, Aldakhil AR. Hypertension and Coronary Heart Disease in Diabetic Patients: A Systematic Review. Arch Pharm Pract. 2020;1:130-4.

3.        Choi DJ, Park JJ, Yoon M, Park SJ, Jo SH, Kim EJ, et al. Self-Monitoring of Blood Pressure and Feed-back Using APP in TReatment of UnconTrolled Hypertension (SMART-BP): A Randomized Clinical Trial. Korean Circ J. 2022;52(10):785-94.

4.        Medeiros LS, Santos FH, Almeida AP, Alves DMO, Rocca RR, Tufik S, et al. Sex differences in the cognitive performance in adults: role of impaired sleep. Sleep Sci. 2022;15(1):17-25.

5.        Huang NX, Gao ZL, Lin JH, Lin YJ, Chen HJ. Altered stability of brain functional architecture after sleep deprivation: A resting-state functional magnetic resonance imaging study. Front Neurosci. 2022;16:998541. doi:10.3389/fnins.2022.998541

6.        Reitz CJ, Rasouli M, Alibhai FJ, Khatua TN, Pyle WG, Martino TA. A brief morning rest period benefits cardiac repair in pressure overload hypertrophy and postmyocardial infarction. JCI Insight. 2022;7(22):e164700. doi:10.1172/jci.insight.164700

7.        Shah R, St-Onge MP, Emin M, Gao S, Sampogna RV, Aggarwal B, et al. Sleep Deprivation Impairs Vascular Function in Healthy Women: A Clinical Trial. Ann Am Thorac Soc. 2022;19(12):2097-100. doi:10.1513/AnnalsATS.202205-406RL

8.        Zhong X, Gou F, Jiao H, Zhao D, Teng J. Association between night sleep latency and hypertension: A cross-sectional study. Medicine (Baltimore). 2022;101(42):e31250. doi:10.1097/MD.0000000000031250

9.        Alismail AI, Alosaimi WA, Faqihi AY, Al-Sahagi RJ, Alfraiji AF, Aloofy OA, et al. Hypertension Diagnosis and Management Approach. Int J Pharm Res Allied Sci. 2020;9(1).

10.     Casagrande M, Favieri F, Langher V, Guarino A, Di Pace E, Germanò G, et al. The Night Side of Blood Pressure: Nocturnal Blood Pressure Dipping and Emotional (dys)Regulation. Int J Environ Res Public Health. 2020;17(23):8892. doi:10.3390/ijerph17238892

11.     Zhang X, Huang W, Xu H, Li X, Wang F, Wu K, et al. Associations between common sleep disturbances and cardiovascular risk in patients with obstructive sleep apnea: A large-scale cross-sectional study. Front Cardiovasc Med. 2022;9:1034785. doi:10.3389/fcvm.2022.1034785

12.     Jiang W, Hu C, Li F, Hua X, Zhang X. Association between sleep duration and high blood pressure in adolescents: a systematic review and meta-analysis. Ann Hum Biol. 2018;45(6-8):457-62. doi:10.1080/03014460.2018.1535661

13.     Quist JS, Sjödin A, Chaput JP, Hjorth MF. Sleep and cardiometabolic risk in children and adolescents. Sleep Med Rev. 2016;29:76-100. doi:10.1016/j.smrv.2015.09.001

14.     Rafati S, Isheh M, Azarbad A, Ghadiri Soufi F, Rahimi A, Kheirandish M. The association of sleep duration and metabolic syndrome in the Bandare-Kong cohort study, a cross-sectional survey (finding from PERSIAN cohort study). Diabetol Metab Syndr. 2021;13(1):114. doi:10.1186/s13098-021-00737-1

15.     Fung MM, Peters K, Redline S, Ziegler MG, Ancoli-Israel S, Barrett-Connor E, et al. Decreased slow wave sleep increases the risk of developing hypertension in elderly men. Hypertension. 2011;58(4):596-603. doi:10.1161/HYPERTENSIONAHA.111.174409

16.     Su Y, Li C, Long Y, He L, Ding N. Association between sleep duration on workdays and blood pressure in non-overweight/obese population in NHANES: public database research. Sci Rep. 2022;12(1):1133.

17.     Guan Y, Zhang M, Zhang X, Zhao Z, Huang Z, Li C, et al. Association between sleep duration and hypertension of migrant workers in China: a national cross-sectional surveillance study. BMJ Open. 2019;9(11):e031126. doi:10.1136/bmjopen-2019-031126

18.     He J, He Q. Association between Sleep Duration and Hypertension among Adults in Southwest China. Global Heart. 2022;17(1):10.

19.     Ogugu EG, Catz SL, Bell JF, Drake C, Bidwell JT, Gangwisch JE. The Association Between Habitual Sleep Duration and Blood Pressure Control in the United States (US) Adults with Hypertension. Integr Blood Press Control. 2022;15:53-66.

20.     Li M, Yan S, Jiang S, Ma X, Gao T, Li B. Relationship between sleep duration and hypertension in northeast China: a cross-sectional study. BMJ Open. 2019;9(1):e023916. doi:10.1136/bmjopen-2018-023916

21.     Santos ESGD, Souza OF. Evidence of the association between sleep duration and blood pressure in adolescents: A systematic review. Rev Paul Pediatr. 2021;39:e2019225. doi:10.1590/1984-0462/2021/39/2019225

22.     e Farias AV, de Lima Cavalcanti MP, de Passos Junior MA, del Vechio Koike B. The association between sleep deprivation and arterial pressure variations: a systematic literature review. Sleep Med X. 2022;4:100042.

23.     Wang Y, Mei H, Jiang YR, Sun WQ, Song YJ, Liu SJ, et al. Relationship between duration of sleep and hypertension in adults: a meta-analysis. J Clin Sleep Med. 2015;11(9):1047-56.

24.     Alves JM, Chow T, Nguyen-Rodriguez S, Angelo B, Defendis A, Luo S, et al. Associations Between Sleep and Metabolic Outcomes in Preadolescent Children. J Endocr Soc. 2022;6(11):bvac137. doi:10.1210/jendso/bvac137

25.     Arregi A, Lertxundi A, Vegas O, García-Baquero G, Ibarluzea J, Anabitarte A, et al. Environmental Noise Exposure and Sleep Habits among Children in a Cohort from Northern Spain. Int J Environ Res Public Health. 2022;19(23):16321.

26.     Togeiro SM, Smith AK. Métodos diagnósticos nos distúrbios do sono. Rev Bras Psiquiatr. 2005;27(1):8-15. doi:10.1590/S1516-44462005000500003

27.     Becker SP, Langberg JM, Eadeh HM, Isaacson PA, Bourchtein E. Sleep and daytime sleepiness in adolescents with and without ADHD: differences across ratings, daily diary, and actigraphy. J Child Psychol Psychiatry. 2019;60(9):1021-31.

28.     Wang Y, Luo S, Hou Y, Wang K, Zhang Y. Association between overweight, obesity and sleep duration and related lifestyle behaviors is gender and educational stages dependent among children and adolescents aged 6-17 years: a cross-sectional study in Henan. BMC Public Health. 2022;22(1):1650.

29.     Doyle CY, Ruiz JM, Taylor DJ, Smyth JW, Flores M, Dietch JR, et al. Associations Between Objective Sleep and Ambulatory Blood Pressure in a Community Sample. Psychosom Med. 2019;81(6):545-56.

30.     Dos Santos ESG, De Souza OF. Association of Sleep Duration and Blood Pressure in Adolescents: A Multicenter Study. Am J Hypertens. 2020;33(1):77-83.

31.     Giannakopoulos G, Kolaitis G. Sleep problems in children and adolescents following traumatic life events. World J Psychiatry. 2021;11(2):27-34.

32.     Ahmadi Z, Omidvar S. The quality of sleep and daytime sleepiness and their association with quality of school life and school achievement among students. J Educ Health Promot. 2022;11:159.

33.     Abdalla M, Schwartz JE, Cornelius T, Chang BP, Alcántara C, Shechter A. Objective short sleep duration and 24-hour blood pressure. Int J Cardiol Hypertens. 2020;7:100062.

34.     Hijmans JG, Levy M, Garcia V, Lincenberg GM, Diehl KJ, Greiner JJ, et al. Insufficient sleep is associated with a pro-atherogenic circulating microRNA signature. Exp Physiol. 2019;104(6):975-82.

35.     Khokhrina A, Andreeva E, Degryse JM. A systematic review on the association of sleep-disordered breathing with cardiovascular pathology in adults. NPJ Prim Care Respir Med. 2022;32(1):41.

36.     Gnyawali S, Feigl B, Adhikari P, Zele AJ. The role of melanopsin photoreception on visual attention linked pupil responses. Eur J Neurosci. 2022;55(8):1986-2002.

37.     Park SY, Lee HM, Kim J. The Number of Monthly Night Shift Days and Depression Were Associated with an Increased Risk of Excessive Daytime Sleepiness in Emergency Physicians in South Korea. Behav Sci (Basel). 2022;12(8):279.

38.     Attia DA, Al-kadhi NA, Saeed IA, Abass KS. Sleep deprivation effect on the concentration of some reproductive hormones in healthy men and women volunteers. J Adv Pharm Educ Res. 2021;11(1):157.

39.     Mansour W, Knauert M. Adding Insult to Injury: Sleep Deficiency in Hospitalized Patients. Clin Chest Med. 2022;43(2):287-303.

40.     Teshome DF, Balcha SA, Ayele TA, Atnafu A, Sisay M, Asfaw MG, et al. High burden of hypertension amongst adult population in rural districts of Northwest Ethiopia: A call for community based intervention. PLoS One. 2022;17(10):e0275830.

41.     Peila R, Xue X, Feliciano EMC, Allison M, Sturgeon S, Zaslavsky O, et al. Association of sleep duration and insomnia with metabolic syndrome and its components in the Women's Health Initiative. BMC Endocr Disord. 2022;22(1):228.

42.     Garu A, Nitta E, Yoshida Y, Yata E, Tsunematsu A, Araki T, et al. Does overnight duty affect vascular endothelial function? BMC Cardiovasc Disord. 2021;21(1):467.

43.     Li H, Ren Y, Wu Y, Zhao X. Correlation between sleep duration and hypertension: a dose-response meta-analysis. J Hum Hypertens. 2019;33(3):218-28. doi:10.1038/s41371-018-0135-1

44.     Matthews EE, Li C, Long CR, Narcisse MR, Martin BC, McElfish PA. Sleep deficiency among Native Hawaiian/Pacific Islander, black, and white Americans and the association with cardiometabolic diseases: analysis of the national health interview survey data. Sleep Health. 2018;4(3):273-83. doi:10.1016/j.sleh.2018.01.004

45.     Grandner M, Mullington JM, Hashmi SD, Redeker NS, Watson NF, Morgenthaler TI. Sleep duration and hypertension: analysis of > 700,000 adults by age and sex. J Clin Sleep Med. 2018;14(6):1031-9. doi:10.5664/jcsm.7176

46.     Bhat SH, Ullah MF, Abu-Duhier FM. Anti-hemolytic activity and antioxidant studies of Caralluma quadrangular: potential for nutraceutical development in cancers and blood disorders. Int J Pharm Res Allied Sci. 2019;8(4):121-9.

47.     Lusardi P, Zoppi A, Preti P, Pesce RM, Piazza E, Fogari R. Effects of insufficient sleep on blood pressure in hypertensive patients: a 24-h study. Am J Hypertens. 1999;12(1):63-8. doi:10.1016/s0895-7061(98)00200-3

48.     Yang H, Haack M, Gautam S, Meier-Ewert HK, Mullington JM. Repetitive exposure to shortened sleep leads to blunted sleep-associated blood pressure dipping. J Hypertens. 2017;35(6):1187-94. doi:10.1097/HJH.0000000000001284