The Diagnosis and Treatment of Snoring in Adults

Abstract

Background

Snoring in adults is a common cause of distress for patients and their bedpartners and calls for appropriate counseling, diagnostic evaluation, and treatment.

Methods

A systematic literature search in the PubMed, Cochrane Library, Web of Science Core Collection, and ClinicalTrials.gov databases was carried out in February 2018 and yielded pertinent publications from 2000 onward. The guideline was created according to the methodological requirements of the Association of the Scientific Medical Societies in Germany (Arbeitsgemeinschaft der wissenschaftlichen medizinischen Fachgesellschaften, AWMF).

Results

The diagnostic evaluation of snoring is based on the history and phyical examination. In certain situations, a specialized sleep study should be performed to obtain objective findings. The recommended methods of conservative treatment include, in particular, positioning therapy and weight loss. Mandibular protrusion splints can lessen snoring in suitable cases. If breathing through the nose is impaired, rhinological or rhinosurgical treatment is recommended; for certain anatomical abnormalities of the soft palate, a suitable minimally invasive surgical procedure can be considered. The level of the available evidence is low, as most of the underlying clinical studies involved small patient groups and short follow-up.

Conclusion

In the treatment of snoring, evidence-based recommendations derived from the findings of randomized trials can be given for selected situations, yet the overall state of the evidence on many diagnostic and therapeutic techniques remains limited.

Due to its frequency and the burden it creates on those affected, snoring in adults requires expert consultation, diagnosis, and, where necessary, treatment. Snoring can manifest either as an independent phenomenon or as a symptom of a sleep disorder, such as obstructive sleep apnea (OSA). The latter is not dealt with in this guideline. Epidemiological studies on the frequency of snoring are rare and OSA can generally not be reliably ruled out. Since the underlying definitions are often not standardized, data on prevalence vary between 2 and 86% (1). In the UK, 20% of women and 26% of men up to the age of 24 years report regular snoring. The highest prevalence for snoring is attained between the ages of 45 and 54 years; however, there are no data for Germany (2).

Whereas OSA represents a confirmed cardiovascular risk factor, the situation is difficult to determine for isolated snoring. A handful of prospective studies suggest possible negative cardiovascular effects—however, the clinical relevance of these data is virtually impossible to estimate at present and, as such, they provide no guidance on the need to treat (3, 4).

There are also scarcely any guidelines on snoring in the international literature. This is in part due to the difficulty of defining objective parameters on symptom severity and, as a result, achieving treatment success, as well as to a lack of controlled treatment studies.

This guideline is addressed to all those involved in the diagnosis and treatment of snoring. The central questions relate to:

• The value of individual diagnostic methods (sleep nasendoscopy and pharyngeal manometry)

• The effectiveness of the most important conservative (positional therapy, myofascial therapy, weight reduction, and mandibular advancement splints) and surgical (soft palate and nasal surgery) treatment options.

Methods

The guideline has been drawn up in accordance with the methodological requirements of the Association of the Scientific Medical Societies in Germany (Arbeitsgemeinschaft der wissenschaftlichen medizinischen Fachgesellschaften, AWMF) and represents an S3 guideline. All participants are listed in Box 1.

BOX 1.

Collaborators

• German Society for Oto-Rhino-Laryngology, Head and Neck Surgery (Deutsche Gesellschaft für Hals-Nasen-Ohrenheilkunde, Kopf- und Hals-Chirurgie)

  • Prof. Dr. med. Boris A. Stuck, Marburg

  • Prof. Dr. med. Clemens Heiser, Munich

  • PD Dr. med. Michael Herzog, Cottbus

  • PD Dr. med. Benedikt Hofauer, Freiburg

  • Prof. Dr. med. Joachim T. Maurer, Mannheim

  • Dr. med. Sebastian Plößl, Halle (Saale)

  • Prof. Dr. med. J. Ulrich Sommer, Wuppertal

  • PD Dr. med. Armin Steffen, Lübeck

  • Prof. Dr. med. Thomas Verse, Hamburg

• German Sleep Society

  (Deutsche Gesellschaft für Schlafforschung und Schlafmedizin)

  • Prof. Dr. med. Maritta Orth, Mannheim

• German Society of Oral and Maxillofacial Surgery (Deutsche Gesellschaft für Mund-, Kiefer- und Gesichtschirurgie)

  • Prof. Dr. med. Dr. med. dent. Hans Pistner, Erfurt

• German Professional Association of Otolaryngologists (Deutscher Berufsverband der Hals-Nasen-Ohrenärzte)

  • Dr. med. Gerald Gronke, Blankenfelde

• - German Society of Dentistry and Oral Medicine (Deutsche Gesellschaft für Zahn-, Mund- und Kieferheilkunde)

  • Prof. Dr. med. Bert Braumann, Cologne

• German Society of Dental Sleep Medicine (Deutsche Gesellschaft zahnärztliche Schlafmedizin)

  • Dr. med. Markus Heise, Bochum

• German Federal Association Sleep Apnea and Sleep Disorders (Bundesverband Schlafapnoe und Schlafstörungen Deutschlands e. V.)

  • Werner Waldmann, Ostfildern

In a first step, a literature search was conducted in PubMed/MEDLINE for existing Cochrane reviews, as well as earlier guidelines or systematic review articles. Guidelines were evaluated and considered in accordance with the German guideline assessment instrument (Deutsches Leitlinien-Bewertungsinstrument, DELBI), and systematic review articles in accordance with standardized criteria (Revised Assessment of Multiple SysTemAtic Reviews, AMSTAR) (5). The general literature search was conducted from 2000 onwards in the PubMed, Cochrane Library, Web of Science Core Collection, and ClinicalTrials.gov databases (ebox). The results of the literature selection are presented in the form of a PRISMA diagram (PRISMA, Preferred Reporting Items for Systematic Reviews and Meta-Analyses) (efigure) (6). The selected studies were evaluated on the basis of a standardized procedure and the results transferred to evidence tables (summarized in the Table). The evidence levels of the publications were assessed according to the levels defined by the Oxford Center for Evidence-Based Medicine (OCEBM).

eBOX. Literature search.

Search for Cochrane reviews, guidelines, and systematic review articles

The consensus conference was conducted and the recommendations formulated in accordance with the standards of an S3 guideline. Prior to adoption by the chairmanships of the participating professional associations, a consultation version was published in order to give those not directly involved in the guideline process the opportunity to submit comments. In January 2018, a literature search was conducted, with no date restrictions, for reviews in the Cochrane Library using the search term “snoring.” In addition, a further literature search was carried out simultaneously, without date restrictions, for already existing guidelines or systematic reviews in PubMed/MEDLINE, again using the search term “snoring” and the following limits: “guideline,” “systematic reviews,” “humans,” “adults,” “English,” and “German.” The guidelines found in this process were evaluated and taken into consideration in the drawing-up of the guideline according to standardized criteria (German guideline assessment instrument [Deutsches Leitlinien-Bewertungsinstrument, DELBI]). The systematic review articles identified were evaluated in line with the recommendations of the Association of the Scientific Medical Societies in Germany (Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften, AWMF) according to standardized criteria (Revised Assessment of Multiple SysTemAtic Reviews [AMSTAR]) and also taken into consideration in the drawing-up of the guideline.

General literature search

A systematic literature search was carried out on 1 February 2018 by an appropriately qualified librarian (Maurizio Grilli M.L.I.S.) at the library of the Mannheim Medical Faculty of the University of Heidelberg. Publications from 2000 onwards were sought in the PubMed, Cochrane Library, Web of Science Core Collection, and ClinicalTrials.gov databases. The date restriction was chosen since, in general, no reliable distinction between snoring and obstructive sleep apnea (OSA) was made prior to 2000. The results of the systematic literature search were grouped according to topic and made available to the chapter authors. In a first step, articles that were patently not relevant on the basis of their abstract were excluded by the authors. All abstracts were independently assessed by two authors; an article was considered relevant on the basis of its abstract if one of the two reviewers defined it as relevant.

In a second step, articles thus deemed relevant were re-assessed on the basis of the full text. Articles deemed to not be relevant were once again excluded, whereby the reasons for excluding articles were now recorded using a schematic. The selection was limited to English and German studies (full text), investigations in adults, and studies in which OSA was excluded on the basis of instrument-based measurement. Studies on the effectiveness of measures needed to have a minimum group size of 10 participants. Here again, a study was deemed relevant if one of the two reviewers considered it to be relevant. The results of the literature selection were presented for each chapter in the form of a PRISMA diagram (PRISMA, Preferred Reporting Items for Systematic Reviews and Meta-Analyses). In a final step, the studies thus deemed relevant were reviewed once again by two independent reviewers on the basis of the full text according to systematic criteria and their evidence level was estimated. The results were transferred to an evidence table (table), which shows the relevant literature and most pertinent key data for each chapter. The Oxford Level of Evidence (2009) was used as a basis.

eFigure.

Summarized PRISMA diagram on literature selection

PRISMA, Preferred Reporting Items for Systematic Reviews and Meta-Analyses

Table. Presentation of evidence.

Study type	Patients	Treatment	Main result	Comment
Conservative treatment
Prospective randomized controlled crossover study (1b) (14)	Intervention n = 22 (2 dropouts), control n = 20	Active anti-snoring pillow (intervention), inactive anti-snoring pillow (control)	VAS: inactive 7.2; active 4.0 (p <0.001), snoring index: inactive 269 ± 249.7; active 162 ± 169.8 (p = 0.03)	Treatment period: 1 week
Intraoral devices*
Randomized controlled study (1b) (17)	Intervention n = 20, control n = 20	MAD (intervention), CPAP (control)	MAD: SOS reduction: 10.5 CI: [3.5; 17.5]; SBPS reduction: 14 CI: [3.9; 24] CPAP: SOS reduction: 10 CI: 3.9–16.1]; SBPS reduction: 7.6 CI: [−1.2; 16.4]	Treatment period: 3 months, no difference between the two groups
Randomized controlled crossover study (1b) (20)	Intervention n = 27 (4 dropouts)	MAD (intervention), sham MAD (MAD without advancement; control)	MAD: VAS from 9 (6–10) to 6 (2–10, p = 0.001); snoring index from 398 (51–633) to 17 (11–324, p = 0.002); sham MAD: VAS from 9 (6–10) to 8 (6–10, p = 0.761); snoring index from 398 (51–633) to 427 (48–652, p = 0.728, median values)	Treatment period: 4–6 weeks Side effects such as muscular pain, temporomandibular problems more pronounced with splints that advanced
Randomized controlled crossover study (1b) (18)	Intervention n = 28, control n = 28	MAD (intervention), sham MAD (control)	MAD: snoring frequency from 3.69 ± 0.63 to 1.84 ± 1.40; snoring loudness from 3.23 ± 0.59 to 1.24 ± 0.97; sham MAD: snoring frequency from 3.75 ± 0.45 to 3.36 ± 1.07; snoring loudness from 3.08 ± 0.79 to 2.76 ± 0.97	Treatment period: 4–6 weeks, significantly more pronounced reduction of the listed parameters in the intervention group Most common side effect: hypersalivation
Randomized controlled crossover study (2b) (19)	Intervention n = 52, control n = 52 (14 dropouts in total)	Individually fitted MAD (intervention), occlusal splint (control)	MAD: SSI from 62.3 ± 11.7 to 56.8 ± 12.3 (p = 0.013) Occlusal splint: SSI from 62.3 ± 10.9 to 59.2 ± 11.3 (p = 0.005)	Treatment period: 4 weeks, no difference between groups Most common side effect: short-term facial muscle problems
Soft palate surgery*
Randomized controlled study (1b) (34)	Intervention n = 20, control n = 24	LAUP (intervention), RAUP (control)	LAUP: VAS from 8.0 ± 1.4 to 3.4 ± 2.4 (p <0.05) raup: vas from 7.9 ± 1.3 to 3.3 ± 2.7 (p <0.05)	Treatment period: 6 months; less postoperative pain with RAUP on postoperative days 1 and 7
Randomized controlled study (1b) (32)	Intervention n = 10, control n = 10	Normal soft palate implants (intervention), more rigid soft palate implants (control)	Normal: VAS from 7.7 to 4.7 (p <0.01) rigid: vas from 8.3 to 6.1 (p = 0.53)	Treatment period: 180 days; implant extrusion only in the group with more rigid implants
Randomized controlled study (1b) (25)	Intervention n = 12, control n = 11	RFT of the soft palate (intervention), insertion without energy applied (control)	RFT: VAS from 8.1 ± 1.3 to 5.2 ± 2.4 Control: VAS from 8.4 ± 1.6 to 8.0 ± 2.3	Treatment period: 6–8 weeks, significant difference between groups (p = 0.045)

* Case series are not shown.

CI, confidence interval; CPAP, continuous positive airway pressure; ISP, injection snoreplasty; LAUP, laser-assisted uvulopalatoplasty; MAD, mandibular advancement device;

RAUP, radiofrequency-assisted uvulopalatoplasty; RFT, radiofrequency therapy; SBPS, snoring bed partner survey; SOS, snoring outcomes survey;

SSI, snoring symptoms inventory; VAS, visual analog scale

Definitions

Based on the International Classification of Sleep Disorders (ICSD-3), the diagnosis “snoring” should be made if the following criteria are met (strong consensus) (7, 8):

• The affected individual or their bed partner reports respiration-dependent, generally inspiratory, acoustic phenomena during sleep, whereby objective parameters for the definition of the acoustic phenomena as “snoring” are not available at present.

• The affected individual does not complain of a sleep disorder that could be causally attributed to the snoring.

• Sleep medicine diagnostics yield no indication of the presence of another sleep-related respiratory disorder.

Diagnostic work-up

Standard diagnostic procedures are described below; further procedures may be necessary depending on the individual case and the planned treatment methods (figure 1).

Figure 1.

Diagnostic algorithm for snoring in adults

*¹ Minimum standard: nose, oral cavity, oropharynx, dental status, morphology of the facial skeleton

*² In the case of an unequivocal finding in the instrument-based examination, treatment of an SRBD can be initiated immediately in accordance with the GBA guidelines.

FJC, Federal Joint Committee; OSA, obstructive sleep apnea; PSG, polysomnography; SRBD, sleep-related breathing disorder

Patient history

A patient history—including information from the bed partner where possible—should be taken from snorers (strong consensus). The thorough interview on patient history can be structured according to topic (box 2). The supplementary use of questionnaires is recommended (strong consensus). Validated questionnaires include, for example, the Pittsburgh Sleep Quality Index (PSQI) and the Epworth Sleepiness Scale (ESS), although these are unhelpful from a differential diagnostic perspective.

BOX 2. Components of the detailed patient history interview.

• Specific evaluation of snoring (selected):

  • Temporal occurrence (every night, intermittent, etc.)

  • Occurrence at night (permanent/intermittent, position-dependent)

  • Triggering factors and risk factors (alcohol, nicotine, allergic and non-allergic rhinitis, nasal breathing impairment)

  • Type of snoring (regular/irregular, inspiratory/expiratory, frequency, loudness, noise characteristics)

• Further sleep medicine-relevant history (selected):

  • Sleep-related breathing pauses

  • Daytime sleepiness/tendency to fall asleep

  • Sleep initiation and maintenance disorders

  • Waking from sleep (e.g., with difficulty breathing, dry mouth/throat)

  • Reduced concentration during the day

  • Reduced performance

• Relevant comorbidities (selected):

  • Cardiac and vascular diseases (e.g., arterial hypertension, arrhythmias, myocardial infarction, apoplexy)

  • Overweight or obesity

  • Diabetes mellitus

Clinical examination

The aim of the clinical examination is to identify changes in the upper airways that could be responsible for the production of snoring noises. Although vibrations in endonasal structures are generally not possible due to the stability of the nasal skeleton, impaired nasal breathing can be a co-factor in the development of snoring in other regions, for example, in the region of the soft palate. In the case of a nasal breathing impairment, a clinical examination of the nose should be carried out in order to assess the nasal structures relevant to airflow (strong consensus). An examination of the nose may be helpful even in cases where no nasal breathing impairment has been reported (strong consensus).

Due to its slight tendency to collapse, the oropharynx is a predilection site for the development of snoring noises and its examination (flexible transnasal, rigid transoral) can influence the therapeutic approach. An examination of the oropharynx should be carried out (strong consensus). In the case of clinical suspicion of laryngeal snoring, laryngoscopy should be performed; this can be combined with drug-induced sleep endoscopy (strong consensus).

An examination of the oral cavity should be carried out (strong consensus). If treatment with an advancement splint is considered, an assessment of possible lower jaw protrusion should be performed; dental status should be recorded and a clinical functional assessment of the temperomandibular joint and masticatory muscles made for orientation (consensus).

The diagnostic work-up of snoring should include a clinical assessment of the morphology of the facial skeleton for orientation (strong consensus).

Additional diagnostic methods including technical investigations such as nasal function tests, allergy diagnosis, imaging, and acoustic analysis can be helpful in some cases (strong consensus).

Sleep endoscopy and pharyngeal manometry

Drug-induced sleep endoscopy (DISE) offers the advantage of observing the upper respiratory tract while the patient is in a sleep-like state. DISE can be performed for the purposes of: topographical diagnosis of the upper respiratory tract in the case of snoring alone, differentiation from OSA, and establishing the indication for surgical treatment of the soft palate (evidence level 2b, recommendation grade 0, strong consensus) (9– 12). However, studies on the superiority of this procedure compared to clinical investigation with regard to patient selection for treatment interventions for snoring are not available. Due to the lack of external evidence, it is not possible to make a statement on the use of pressure transducers in the diagnostic work-up of snoring (strong consensus). While pharyngeal manometry is a complementary outpatient examination, the question of whether DISE should be performed on an outpatient or inpatient basis and whether the costs are covered is still largely unresolved.

Polygraphy/polysomnography

Polysomnography is the diagnostic gold standard of sleep medicine investigations; alternatively, (outpatient) cardiorespiratory polygraphy can be used under certain conditions (13). An instrument-based sleep medicine investigation (such as polygraphy or a comparable procedure) should be performed in cases in which:

• Another sleep-related breathing disorder is suspected

• A patient wishes to be treated for snoring

• Relevant cardiovascular vascular comorbidities are present (strong consensus).

Treatment

Snoring as defined in this guideline is currently not considered a disease and, as such, is only treated if a patient desires treatment. The methods described below (figure 2) can be used either in isolation or in combination. While some treatment options can be evaluated on the basis of randomized controlled trials (such as snoring-triggered changes in head position, treatment with intraoral devices, and surgical treatment of the soft palate), only case control series (surgical treatment of the nose) or no relevant studies (weight reduction, myofascial therapy) are available for other options.

Figure 2.

Algorithm for the treatment of snoring in adults

*¹ Counseling on lifestyle and sleep hygiene, nicotine avoidance in smokers, head position modification

*² The presence of nasal obstruction requires appropriate investigation irrespective of snoring.

Other conservative and surgical methods not mentioned here may be indicated in such cases on the basis of a rhinological indication; this can lead to an improvement in concomitant snoring.

*³ Radiofrequency surgery: EL 1b, RG A

Soft palate implants EL, RG B

EC, expert consensus; EL, evidence level; RG, recommendation grade

Conservative approaches

The conservative approaches for which effectiveness has been evaluated include positional therapy, myofascial therapy, and weight reduction (table). Due to a lack of clinical studies, no evidence-based statement can be made on the efficacy of avoidance of a supine position (strong consensus). In the case of supine position-related snoring, an attempt at treatment by avoiding the supine position should be offered (evidence level 5, recommendation grade B, strong consensus). A randomized controlled study (RCT) with a total of 22 patients investigated the effect of a pillow that is able to trigger a change in head position when snoring is registered (14). A reduction was seen in both polysomnographically measured and subjectively determined snoring intensity. Snoring-triggered change of head position should be offered for the reduction of snoring (evidence level 1b, recommendation grade B, strong consensus).

There is currently insufficient evidence to recommend myofascial measures for the treatment of snoring (strong consensus).

Only studies on weight reduction in patients with OSA are available in the literature. A decrease in body mass index (BMI) results in a reduction in snoring particularly in patients with overweight or obesity and OSA (15). A reduction in BMI should be recommended for all overweight snorers, despite the scarcity of scientific evidence on this (evidence level 5, recommendation grade A, strong consensus).

In the case of impaired nasal breathing in the area of the nasal valve, an attempt at treatment with internal or external nasal dilators should be proposed (strong consensus). The short-term use of decongestant nasal spray/drops to simulate surgical treatment of the nasal concha can be considered (strong consensus). Systemic drug treatment or local intraoral use of oils or sprays is not recommended (strong consensus).

Intraoral devices

Mandibular advancement devices (MAD), which are no different to those used to treat OSA, can be used to control snoring (table) (16). A crossover trial compared the effectiveness of MAD in terms of snoring reduction and the effect on quality of life with CPAP (continuous positive airway pressure) therapy (17). MAD were able to significantly reduce the snoring outcome score. In an RCT, an MAD showed superior reduction in snoring compared to a placebo splint (18). Another RCT demonstrated a significant improvement in the snoring symptoms inventory compared to a placebo splint (19). In suitable cases (box 3), and when treatment is desired, the management of snoring with the use of an MAD can be recommended (evidence level 1b, recommendation grade A, strong consensus). The fitting and monitoring of an MAD should be carried out in conjunction with dental and sleep medicine experts (evidence level 5, recommendation grade A, strong consensus). The available studies with short follow-up times do not permit any reliable statements to be made on possible long-term side effects/complications in the indication of snoring. Bearing the literature on OSA in mind, attention should be paid in the case of long-term use to side effects in the area of the stomatognathic system (for example, changes in bite and tooth position). An MAD should only be considered if the mandible has sufficient mobility to be advanced (evidence level 5, recommendation grade B, strong consensus).

BOX 3. Definition of cases suitable for treatment with an MAD.

In the absence of reliable evidence, the assessment of which cases are suitable for a mandibular advancement device (MAD) is carried out on the basis of conventional dental indexes and classifications (e.g., BOP index [bleeding on probing], anamnestic dysfunction index and clinical dysfunction index according to Helkimo, the Eichner classification) and clinical findings (e.g., extent of protrusion, number of teeth present, extent of probing depths, extent of bone resorption, number of teeth with degrees of loosening). In the authors‘ opinion, the following conditions for the use of an MAD are thus defined:

• An adequate number of sufficiently stable, caries- and inflammation-free teeth per jaw in a periodontally health environment or a sufficient number of robust dental or orthodontic implants

• Sufficient ability to open the mouth

• Unremarkable clinical function analysis (34, 35).

Thermoplastic splints are discussed critically in terms of their durability and effectiveness. However, in an RCT, effectiveness was also documented for a partially adjustable thermoplastic splint (20). Robust evidence-based long-term data on the effectiveness and side effects of ready-made splints were not available at a the time of drawing-up this guideline.

Surgical approaches

In many cases, there is only scant long-term evidence on the success rates of surgical treatment options, and not all procedures have been sufficiently evaluated as yet. The selection and efficacy of a procedure depend to a crucial extent on the individual anatomical findings and on BMI. Minimally invasive surgical procedures should be preferred for the surgical management of snoring (strong consensus).

The efficacy of surgical methods in the nasal region has been investigated in a number of case control series, whereby the follow-up period was generally 6 months. A retrospective study compared the effectiveness of septoplasty and turbinoplasty with other surgical procedures for snoring and a significant improvement in subjective snoring intensity was seen (21). Prospective case control series also demonstrated the effect of septoplasty alone on subjective, but not objective, snoring intensity (22– 24). The results of the above-mentioned studies suggest that a surgical improvement in nasal airflow leads to a subjective reduction in snoring. Possible side effects and complications of the procedure do not differ from nasal surgery for a primary rhinological indication. In the case of a primary rhinological indication to improve subjective nasal breathing impairment, surgical treatment for snoring should be offered; this is able to achieve a subjective improvement in snoring (evidence level 3b, recommendation grade B, strong consensus). According to current evidence, nasal surgery with the aim of reducing simple snoring in patients with concomitant nasal breathing impairment should be offered (evidence level 3b, recommendation grade B, strong consensus). Due to a lack of evidence, no statement can be made on the effectiveness of nasal surgery in snorers with no subjective nasal breathing impairment (strong consensus).

The comparatively high number of publications on soft palate surgery reflects its significance in the treatment of snoring (table). However, reliable clinical studies are only available for uvulopalatopharyngoplasty (UPPP), a modification of uvulopalatoplasty, radiofrequency (RAUP) or laser-assisted UPP (LAUP), radiofrequency therapy (RFT), and soft palate implants. The efficacy of interstitial RFT was investigated as part of an RCT (25). With regard to a reduction in snoring, a significant difference was seen between the groups at 6–8 weeks following treatment. The combination of interstitial therapy and radiofrequency-assisted resection of excess mucosa appears to enhance the effect (26). However, an investigation on the long-term effect of this combined approach showed snoring intensity to increase again after 1.5 years (27).

Two other working groups observed a similar development in the long-term course (28, 29). In a direct comparison of RFT of the soft palate and injection snoreplasty, a reduction in snoring intensity was achieved in both groups 6 weeks following the intervention. This reduction was greater in the radiofrequency group than in the comparison group (30). Postoperative pain following RFT of the soft palate is low compared to other soft palate procedures, and complications such as mucosal ulceration/defects are rare when the procedure is performed correctly.

In a collective of 99 patients, a reduction in snoring intensity was seen 3 months following treatment with soft palate implants (31). An RCT investigated whether more rigid implants have a greater effect compared to conventional implants—this, however, could not be confirmed (32). The patients with regular implants were followed-up over a period of 3 years (33); snoring intensity determined by means of visual analog scales was reduced. Differing extrusion rates depending on the properties of the implants have been reported. In the case of early extrusion, the affected implants can be removed and de novo implantation is possible.

If the soft palate is the suspected source of snoring, therapy in the form of surgical procedures on the soft palate should be proposed in cases where treatment is desired (evidence level 1b, recommendation grade A, consensus). If soft palate surgery is performed, minimally invasive procedures such as radiofrequency therapy (evidence level 1b, recommendation grade A) or soft palate implants in specific indications (evidence level 4, recommendation grade B) should be used while taking the individual anatomy of the patient into consideration (strong consensus). The indication for invasive UPPP, which is usually performed with tonsillectomy, should be made on the basis of strict criteria due to its increased morbidity and complication rate (strong consensus).

Minimally invasive procedures on the base of the tongue and palatine tonsils may be beneficial in the treatment of snoring in individual cases (strong consensus). Invasive surgical procedures outside the nose and soft palate are not recommended for the treatment of snoring (strong consensus).

Need for further research

The following research questions arose from an analysis of the available literature:

• Do DISE or pharyngeal manometry recordings have an additional predictive value with regard to the selection of a treatment procedure?

• Does snoring improve following weight loss in overweight or obese snorers?

• Is positional therapy to prevent a supine position also effective in snoring?

• Are there clinical predictors for the effectiveness of MAD in snoring?

Summary

This guideline on the diagnosis and treatment of snoring in adults contains recommendations on the diagnostic work-up of snoring, as well as its conservative, instrument-based, and surgical treatment.

Key messages.

• The diagnostic work-up of snoring consists of patient history and clinical examination; in defined situations, an instrument-based sleep medicine investigation should be carried out in order to differentiate snoring from obstructive sleep apnea.

• Whereas positional therapy and weight reduction are recommended as conservative approaches, there is insufficient evidence to recommend myofascial therapies.

• Mandibular advancement devices represent a potential instrument-based treatment option in suitable cases.

• Surgical treatment of the nose should be offered in the case of concomitant nasal breathing impairment.

• In cases where the soft palate is suspected of being the source of snoring, defined surgical procedures should be offered if patient anatomy is suitable.