The somnometabolic syndrome

Sanjay Kalra; Navneet Agrawal; Saptarshi Bhattacharya; Rakesh Sahay

doi:10.4103/bjem.bjem_8_22

MINI REVIEW

Year : 2022 | Volume : 1 | Issue : 1 | Page : 5-6

The somnometabolic syndrome

Sanjay Kalra¹, Navneet Agrawal², Saptarshi Bhattacharya³, Rakesh Sahay⁴
¹ Department of Endocrinology, Bharti Hospital, Karnal, Haryana, India
² Department of Diabetology, Diabetes Obesity Thyroid Centre, Gwalior, Madhya Pradesh, India
³ Department of Endocrinology, Indraprastha Apollo Hospitals, New Delhi, India
⁴ Department of Endocrinology, Osmania Medical College, Hyderabad, Telangana, India

Date of Submission	31-May-2022
Date of Decision	01-Jun-2022
Date of Acceptance	01-Jun-2022
Date of Web Publication	27-Jun-2022

Correspondence Address:
Dr. Sanjay Kalra
Department of Endocrinology, Bharti Hospital, Kunjpura Road, Karnal - 132 001, Haryana
India

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/bjem.bjem_8_22

Abstract

Obstructive sleep apnea (OSA) and the various components of metabolic syndrome are closely interrelated. We propose the term somnometabolic syndrome to define the condition where OSA coexists with one or more components of metabolic syndrome. Such a definition reinforces the strong association between OSA and metabolic syndrome and will urge the clinician to screen and diagnose OSA in individuals with metabolic syndrome and vice versa. It is hoped that the usage of this new term will not only address the lacunae in screening and treatment of OSA in individuals with metabolic syndrome but will also foster collaboration and research among specialties managing OSA.

Keywords: Diabetes, metabolic syndrome, obesity, obstructive sleep apnea

How to cite this article:
Kalra S, Agrawal N, Bhattacharya S, Sahay R. The somnometabolic syndrome. Bangladesh J Endocrinol Metab 2022;1:5-6

How to cite this URL:
Kalra S, Agrawal N, Bhattacharya S, Sahay R. The somnometabolic syndrome. Bangladesh J Endocrinol Metab [serial online] 2022 [cited 2023 May 30];1:5-6. Available from: https://www.bjem.org/text.asp?2022/1/1/5/348388

Introduction

The metabolic syndrome is a slippery eel to catch. First identified by Reaven in 1988 as syndrome X, it has been the subject of much attention.^[1] Numerous definitions have emerged, some glucocentric, others focusing on insulin resistance, and yet others barocentric or based on anthropometry.^[2] Evidence linking the various components of metabolic syndrome to one another and also to adverse cardiovascular outcomes has accumulated since then.

Rationale of a Syndrome

There is increasing appreciation of newer associations in pathophysiology and clinical presentation of “viscerometabolic” health and diabetes. These include nonalcoholic fatty liver disease, polycystic ovary syndrome, obstructive sleep apnea (OSA), and male late-onset hypogonadism, to name a few.^[3] These conditions may occur independently or in association with other components of metabolic syndrome such as hypertension and dyslipidemia. These comorbidities also influence the choice of therapy for diabetes so that atherosclerotic cardiovascular disease and premature mortality can be prevented.

Such associations are especially significant in the context of OSA. OSA is a sleep-related breathing disorder characterized by repetitive episodes of complete or partial collapse of the upper airway during sleep, dry mouth or sore throat upon awakening, and cognitive impairment.^[4] Although primarily considered a sleep-related disorder, OSA has multiple metabolic facets. OSA is associated with insulin resistance and contributes to cardiovascular morbidity. Untreated OSA, and other sleep disorders, can impair glucose metabolism and adipocyte function. It can lead to “refractory” or difficult-to-manage diabetes and hypertension.^[5]

Limitations of Current Terminology

The current terminologies, OSA and metabolic syndrome, do not convey any commonality. Perhaps, because of this, OSA and metabolic syndrome are not infrequently approached separately in clinical practice. This leads to suboptimal screening strategies, which delays diagnosis and prevents the optimization of comorbid conditions.

SomnoMetabolic Syndrome

We, therefore, suggest the term “somnometabolic syndrome” to highlight the intricate and multifaceted relationship between OSA and metabolic syndrome. It is challenging to propose a unitary definition of somnometabolic syndrome, as no unified description exists for metabolic syndrome itself. Nonetheless, we define somnometabolic syndrome as a clinical condition where OSA is associated with one or more of the various components of metabolic syndrome, as defined by multiple international authorities. It must be noted that the various components of somnometabolic syndrome, listed in [Box 1], may be comorbid conditions, but also often mimic each other (e.g., late-onset hypogonadism and OSA, heart failure, and OSA).^[5]

Advantages of Novel Terminology

A defining characteristic of OSA is the presence of daytime symptoms; on the other hand, somnometabolic syndrome is a more inclusive term. The term “somnometabolic syndrome” sensitizes health-care professionals to screen persons with metabolic dysfunction for OSA. It also reminds them to view OSA as a multisystemic, metabolic malady rather than an upper respiratory or sleep disorder. Such a nomenclature alerts the treating clinician to screen individuals with metabolic dysfunction for OSA. The term “syndrome z” has been used in the literature for this entity but fails to portray the constituent components.^[6]

Screening strategies for metabolic and vascular disease are well defined. However, many physicians are unaware of how easy it is to screen for OSA. The STOP and STOP-Bang questionnaires are simple 4- and 8-item tools used for the outdoor patient.^[7],[8] Filled by the patient, they are objective and require just “yes” or “no” answers. Other tools are also available and can be used for more detailed evaluation.

The diagnosis of OSA can be substantiated in a nonintrusive manner using an overnight home sleep study test.^[9] Once this is done, appropriate treatment can be instituted to achieve symptomatic relief and metabolic optimization.

Somnometabolic syndrome, as a phrase, reminds us to evaluate a person comprehensively with OSA and reemphasizes its close metabolic connect. It also assists in explaining the importance of managing OSA and motivating affected individuals to accept and adhere to the therapy. The term encourages teamwork between various medical specialties that manage OSA. It stimulates discussion and debate, as we hope this editorial will do, and create novel ideas and activities which help our profession achieve its overarching aim ensuring optimal health for all.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1.	Reaven GM. Banting lecture 1988. Role of insulin resistance in human disease. Diabetes 1988;37:1595-607.
2.	Parikh RM, Mohan V. Changing definitions of metabolic syndrome. Indian J Endocrinol Metab 2012;16:7-12.
3.	Cho LW. Metabolic syndrome. Singapore Med J 2011;52:779-85.
4.	Patel SR. Obstructive Sleep Apnea. Ann Intern Med 2019;171:C81-96.
5.	Kim SD, Cho KS. Obstructive sleep apnea and testosterone deficiency. World J Mens Health 2019;37:12-8.
6.	Castaneda A, Jauregui-Maldonado E, Ratnani I, Varon J, Surani S. Correlation between metabolic syndrome and sleep apnea. World J Diabetes 2018;9:66-71.
7.	Chung F, Abdullah HR, Liao P. STOP-bang questionnaire: A practical approach to screen for obstructive sleep apnea. Chest 2016;149:631-8.
8.	Chung F, Yegneswaran B, Liao P, Chung SA, Vairavanathan S, Islam S, et al. STOP questionnaire: A tool to screen patients for obstructive sleep apnea. Anesthesiology 2008;108:812-21.
9.	Serrano Alarcón Á, Martínez Madrid N, Seepold R. A minimum set of physiological parameters to diagnose obstructive sleep apnea syndrome using non-invasive portable monitors. A systematic review. Life (Basel) 2021;11:1249.