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Smell in Covid-19 and Efficacy of Nasal Theophylline (SCENT2)

Primary Purpose

Covid19, Anosmia, Olfactory Disorder

Status
Completed
Phase
Phase 2
Locations
United States
Study Type
Interventional
Intervention
Theophylline Powder
Placebo Comparator
Sponsored by
Washington University School of Medicine
About
Eligibility
Locations
Arms
Outcomes
Full info

About this trial

This is an interventional treatment trial for Covid19 focused on measuring Smell, Smell loss, smell dysfunction, olfactory dysfunction, COVID-19, anosmia, theophylline, nasal irrigation

Eligibility Criteria

18 Years - 70 Years (Adult, Older Adult)All SexesDoes not accept healthy volunteers

Inclusion Criteria:

  • Olfactory dysfunction that has persisted for >3 months following suspected COVID-19 infection
  • Residing within the states of Missouri or Illinois.
  • Can read, write, and understand English.

Exclusion Criteria:

  • History of olfactory dysfunction prior to COVID-19 infection
  • Use of concomitant therapies specifically for the treatment of olfactory dysfunction
  • History of olfactory dysfunction longer than 12 months
  • Known existence of nasal polyps, prior sinonasal, or anterior skull-based surgery
  • Dependence on theophylline for comorbid conditions such as asthma and COPD
  • History of an allergic reaction to theophylline or other methylxanthines
  • History of neurodegenerative disease (ie. Alzheimer's dementia, Parkinson's disease, Lewy body dementia, frontotemporal dementia)
  • Pregnant or breastfeeding mothers
  • Current use of medications with significant interactions with theophylline, which include cimetidine, ciprofloxacin, disulfiram, enoxacin, fluvoxamine, interferon-alpha, lithium, mexiletine, phenytoin, propafenone, propranolol, tacrine, thiabendazole, ticlopidine, and troleandomycin.
  • Pre-existing arrhythmias or seizures

Sites / Locations

  • Washington University School of Medicine in Saint Louis

Arms of the Study

Arm 1

Arm 2

Arm Type

Experimental

Placebo Comparator

Arm Label

Theophylline

Placebo

Arm Description

400mg theophylline capsule diluted in 240 mL isotonic nasal saline lavage twice daily for six weeks.

500mg lactose capsule diluted in 240 mL isotonic nasal saline lavage twice daily for six weeks.

Outcomes

Primary Outcome Measures

UPSIT
UPSIT 0-40 with higher scores indicating better results. The response rate defined as the number of participants in each group self-reporting of at least slightly better improvement in the Clinical Global Improvement Scale at 6 weeks post intervention as compared to baseline, devided by the total number of participants in that specific group. The CGI-Improvement Scale has seven response options (from 1 as Very Much Improved to 7 as Very Much Worsened) for answers to the question "Compared to your sense of smell before you started the nasal irrigations, how would you rate your sense of smell now" . Participants reporting 3 as "Minimally Improved", 2 as "Much Improved", or 1 as "Very Much Improved" in the CGI-I will be deemed responders to treatment, and the rate of responders will be compared between the two arms.

Secondary Outcome Measures

University of Pennsylvania Smell Identification Test (UPSIT)
UPSIT 0-40 with higher scores indicating better smell. This test is an objective, clinically validated 40-question forced-choice odor identification test where microencapsulated odorants on a strip are released by scratching. Out of a total of 40 points, normosmia is defined as ≥34 for males and ≥35 for females, and an increase in ≥4 points will be deemed a clinically significant improvement in symptoms.
Change in Questionnaire for Olfactory Dysfunction (QOD) From Baseline to 6 Weeks Post Intervention
Questionnaire for Olfactory Dysfunction (QOD) assesses health-related quality of life of participants based on four factors such as eating, mental health, social interactions, or fear of dysfunction.. The survey also includes questions on parosmia, a phenomena of COVID-related OD. The QOD consists of 17 statements that participants score from 0-3, resulting in a total score from 0 to 51. Higher scores reflect better olfactory-specific QOL.
36-Item Short Form Health Survey (SF-36)
The SF-36 is a well-established 36-item questionnaire evaluating physical functioning, bodily pain, role limitations due to physical health problems, role limitations due to personal or emotional problems, emotional well-being, social functioning, energy/fatigue, and general health perceptions. This test allows us to study the overall quality of life for those suffering from COVID-19 related OD. There is no single overall score for SF-36. The SF 36 generates 8 subscales with scores ranging from 0 (worst) to 100 (best). General health domain scores are reported here.
Olfactory Dysfunction Outcomes Rating (ODOR)
The ODOR is a 28-item QOL instrument with a total score ranging from 0 to 112 points. Higher scores indicate worse QOL with higher degree of dysfunction and limitation. A decrease of 15 or more points is deemed to be a clinically significant improvement in QOL.

Full Information

First Posted
March 8, 2021
Last Updated
April 27, 2023
Sponsor
Washington University School of Medicine
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1. Study Identification

Unique Protocol Identification Number
NCT04789499
Brief Title
Smell in Covid-19 and Efficacy of Nasal Theophylline
Acronym
SCENT2
Official Title
Smell in Covid-19 and Efficacy of Nasal Theophylline
Study Type
Interventional

2. Study Status

Record Verification Date
April 2023
Overall Recruitment Status
Completed
Study Start Date
March 15, 2021 (Actual)
Primary Completion Date
December 30, 2021 (Actual)
Study Completion Date
December 30, 2021 (Actual)

3. Sponsor/Collaborators

Responsible Party, by Official Title
Sponsor
Name of the Sponsor
Washington University School of Medicine

4. Oversight

Studies a U.S. FDA-regulated Drug Product
Yes
Studies a U.S. FDA-regulated Device Product
No
Product Manufactured in and Exported from the U.S.
Yes
Data Monitoring Committee
Yes

5. Study Description

Brief Summary
Evidence of COVID-19 related anosmia and dysgeusia continues to accumulate daily. Currently, up to 80% of patients report subjective olfactory dysfunction (OD), and prevalence using objective olfactory testing could be even higher. We propose a phase II single-site, double-blinded, placebo-controlled randomized clinical trial to determine the efficacy and safety of intranasal theophylline, a known phosphodiesterase inhibitor in the treatment of asthma, as a possible treatment for COVID-19 related OD. Theophylline has shown benefit in similar clinical trials for post-viral OD.
Detailed Description
Post-viral olfactory dysfunction has numerous known adverse effects such as loss of cortical gray matter and decrease in quality of life. COVID-19 related olfactory dysfunction has already been shown to be correlated with depression and decreased quality of life, so finding an effective treatment is imperative. Intranasal and oral corticosteroids as well as olfactory training are currently used to treat post-viral OD; however they have demonstrated limited efficacy and there is no current gold standard of care. There is no current consensus on the pathogenesis of COVID-related anosmia; however evidence for post-viral olfactory dysfunction suggests sensory axonal regeneration and olfactory signaling may rely on elevated levels of secondary messengers cAMP and cGMP, a known effect of theophylline. In this phase II treatment trial, patients will be allocated 1:1 to receive either intranasal theophylline irrigation or placebo for six weeks. Various smell surveys and scratch-and-sniff tests will be utilized to capture changes in smell ability. Due to COVID-19, this study will be conducted virtually, except for the first ten enrolled patients who will undergo one serum theophylline test. This study is limited to patients living in Missouri or Illinois.

6. Conditions and Keywords

Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Covid19, Anosmia, Olfactory Disorder, Covid-19 Pandemic, SARS-CoV-2 Infection, Hyposmia, Ageusia, Hypogeusia
Keywords
Smell, Smell loss, smell dysfunction, olfactory dysfunction, COVID-19, anosmia, theophylline, nasal irrigation

7. Study Design

Primary Purpose
Treatment
Study Phase
Phase 2
Interventional Study Model
Parallel Assignment
Masking
ParticipantInvestigator
Masking Description
The pharmacy will maintain the blind until the completion of the study.
Allocation
Randomized
Enrollment
51 (Actual)

8. Arms, Groups, and Interventions

Arm Title
Theophylline
Arm Type
Experimental
Arm Description
400mg theophylline capsule diluted in 240 mL isotonic nasal saline lavage twice daily for six weeks.
Arm Title
Placebo
Arm Type
Placebo Comparator
Arm Description
500mg lactose capsule diluted in 240 mL isotonic nasal saline lavage twice daily for six weeks.
Intervention Type
Drug
Intervention Name(s)
Theophylline Powder
Other Intervention Name(s)
Theophylline nasal irrigation
Intervention Description
Twice daily nasal irrigation with 400 mg theophylline capsules and USP Grade Sodium Chloride & Sodium Bicarbonate Mixture (pH balanced, Isotonic & Preservative & Iodine Free) commercially prepared packets dissolved in 240 ml of distilled water.
Intervention Type
Drug
Intervention Name(s)
Placebo Comparator
Other Intervention Name(s)
lactose powder
Intervention Description
Twice daily nasal irrigation with 500 mg lactose powder capsules and USP Grade Sodium Chloride & Sodium Bicarbonate Mixture (pH balanced, Isotonic & Preservative & Iodine Free) commercially prepared packets dissolved in 240 ml of distilled water.
Primary Outcome Measure Information:
Title
UPSIT
Description
UPSIT 0-40 with higher scores indicating better results. The response rate defined as the number of participants in each group self-reporting of at least slightly better improvement in the Clinical Global Improvement Scale at 6 weeks post intervention as compared to baseline, devided by the total number of participants in that specific group. The CGI-Improvement Scale has seven response options (from 1 as Very Much Improved to 7 as Very Much Worsened) for answers to the question "Compared to your sense of smell before you started the nasal irrigations, how would you rate your sense of smell now" . Participants reporting 3 as "Minimally Improved", 2 as "Much Improved", or 1 as "Very Much Improved" in the CGI-I will be deemed responders to treatment, and the rate of responders will be compared between the two arms.
Time Frame
Comparison of response rate at 6 weeks post-intervention from baseline between the 2 study groups
Secondary Outcome Measure Information:
Title
University of Pennsylvania Smell Identification Test (UPSIT)
Description
UPSIT 0-40 with higher scores indicating better smell. This test is an objective, clinically validated 40-question forced-choice odor identification test where microencapsulated odorants on a strip are released by scratching. Out of a total of 40 points, normosmia is defined as ≥34 for males and ≥35 for females, and an increase in ≥4 points will be deemed a clinically significant improvement in symptoms.
Time Frame
Comparison at 6 weeks post-intervention from baseline
Title
Change in Questionnaire for Olfactory Dysfunction (QOD) From Baseline to 6 Weeks Post Intervention
Description
Questionnaire for Olfactory Dysfunction (QOD) assesses health-related quality of life of participants based on four factors such as eating, mental health, social interactions, or fear of dysfunction.. The survey also includes questions on parosmia, a phenomena of COVID-related OD. The QOD consists of 17 statements that participants score from 0-3, resulting in a total score from 0 to 51. Higher scores reflect better olfactory-specific QOL.
Time Frame
Comparison at 6 weeks post-intervention from baseline
Title
36-Item Short Form Health Survey (SF-36)
Description
The SF-36 is a well-established 36-item questionnaire evaluating physical functioning, bodily pain, role limitations due to physical health problems, role limitations due to personal or emotional problems, emotional well-being, social functioning, energy/fatigue, and general health perceptions. This test allows us to study the overall quality of life for those suffering from COVID-19 related OD. There is no single overall score for SF-36. The SF 36 generates 8 subscales with scores ranging from 0 (worst) to 100 (best). General health domain scores are reported here.
Time Frame
Baseline assessment
Title
Olfactory Dysfunction Outcomes Rating (ODOR)
Description
The ODOR is a 28-item QOL instrument with a total score ranging from 0 to 112 points. Higher scores indicate worse QOL with higher degree of dysfunction and limitation. A decrease of 15 or more points is deemed to be a clinically significant improvement in QOL.
Time Frame
Comparison of response rate at 6 weeks post-intervention from baseline between the 2 study groups

10. Eligibility

Sex
All
Minimum Age & Unit of Time
18 Years
Maximum Age & Unit of Time
70 Years
Accepts Healthy Volunteers
No
Eligibility Criteria
Inclusion Criteria: Olfactory dysfunction that has persisted for >3 months following suspected COVID-19 infection Residing within the states of Missouri or Illinois. Can read, write, and understand English. Exclusion Criteria: History of olfactory dysfunction prior to COVID-19 infection Use of concomitant therapies specifically for the treatment of olfactory dysfunction History of olfactory dysfunction longer than 12 months Known existence of nasal polyps, prior sinonasal, or anterior skull-based surgery Dependence on theophylline for comorbid conditions such as asthma and COPD History of an allergic reaction to theophylline or other methylxanthines History of neurodegenerative disease (ie. Alzheimer's dementia, Parkinson's disease, Lewy body dementia, frontotemporal dementia) Pregnant or breastfeeding mothers Current use of medications with significant interactions with theophylline, which include cimetidine, ciprofloxacin, disulfiram, enoxacin, fluvoxamine, interferon-alpha, lithium, mexiletine, phenytoin, propafenone, propranolol, tacrine, thiabendazole, ticlopidine, and troleandomycin. Pre-existing arrhythmias or seizures
Overall Study Officials:
First Name & Middle Initial & Last Name & Degree
Jay F Piccirillo, M.D., FACS
Organizational Affiliation
Washington University School of Medicine
Official's Role
Principal Investigator
Facility Information:
Facility Name
Washington University School of Medicine in Saint Louis
City
Saint Louis
State/Province
Missouri
ZIP/Postal Code
63110
Country
United States

12. IPD Sharing Statement

Citations:
PubMed Identifier
34792577
Citation
Khan AM, Kallogjeri D, Piccirillo JF. Growing Public Health Concern of COVID-19 Chronic Olfactory Dysfunction. JAMA Otolaryngol Head Neck Surg. 2022 Jan 1;148(1):81-82. doi: 10.1001/jamaoto.2021.3379.
Results Reference
background
PubMed Identifier
27287364
Citation
Hoffman HJ, Rawal S, Li CM, Duffy VB. New chemosensory component in the U.S. National Health and Nutrition Examination Survey (NHANES): first-year results for measured olfactory dysfunction. Rev Endocr Metab Disord. 2016 Jun;17(2):221-40. doi: 10.1007/s11154-016-9364-1.
Results Reference
background
PubMed Identifier
32432682
Citation
Whitcroft KL, Hummel T. Olfactory Dysfunction in COVID-19: Diagnosis and Management. JAMA. 2020 Jun 23;323(24):2512-2514. doi: 10.1001/jama.2020.8391. No abstract available.
Results Reference
background
PubMed Identifier
32617983
Citation
Speth MM, Singer-Cornelius T, Oberle M, Gengler I, Brockmeier SJ, Sedaghat AR. Mood, Anxiety and Olfactory Dysfunction in COVID-19: Evidence of Central Nervous System Involvement? Laryngoscope. 2020 Nov;130(11):2520-2525. doi: 10.1002/lary.28964. Epub 2020 Aug 12.
Results Reference
background
PubMed Identifier
34559820
Citation
Burges Watson DL, Campbell M, Hopkins C, Smith B, Kelly C, Deary V. Altered smell and taste: Anosmia, parosmia and the impact of long Covid-19. PLoS One. 2021 Sep 24;16(9):e0256998. doi: 10.1371/journal.pone.0256998. eCollection 2021.
Results Reference
background
PubMed Identifier
3164095
Citation
Schiffman SS, Warwick ZS. Flavor enhancement of foods for the elderly can reverse anorexia. Neurobiol Aging. 1988 Jan-Feb;9(1):24-6. doi: 10.1016/s0197-4580(88)80009-5.
Results Reference
background
PubMed Identifier
12425708
Citation
Murphy C, Schubert CR, Cruickshanks KJ, Klein BE, Klein R, Nondahl DM. Prevalence of olfactory impairment in older adults. JAMA. 2002 Nov 13;288(18):2307-12. doi: 10.1001/jama.288.18.2307.
Results Reference
background
PubMed Identifier
20231262
Citation
Bitter T, Gudziol H, Burmeister HP, Mentzel HJ, Guntinas-Lichius O, Gaser C. Anosmia leads to a loss of gray matter in cortical brain areas. Chem Senses. 2010 Jun;35(5):407-15. doi: 10.1093/chemse/bjq028. Epub 2010 Mar 15.
Results Reference
background
PubMed Identifier
25271633
Citation
Pinto JM, Wroblewski KE, Kern DW, Schumm LP, McClintock MK. Olfactory dysfunction predicts 5-year mortality in older adults. PLoS One. 2014 Oct 1;9(10):e107541. doi: 10.1371/journal.pone.0107541. eCollection 2014.
Results Reference
background
PubMed Identifier
31035288
Citation
Liu B, Luo Z, Pinto JM, Shiroma EJ, Tranah GJ, Wirdefeldt K, Fang F, Harris TB, Chen H. Relationship Between Poor Olfaction and Mortality Among Community-Dwelling Older Adults: A Cohort Study. Ann Intern Med. 2019 May 21;170(10):673-681. doi: 10.7326/M18-0775. Epub 2019 Apr 30.
Results Reference
background
PubMed Identifier
32153360
Citation
Van Regemorter V, Hummel T, Rosenzweig F, Mouraux A, Rombaux P, Huart C. Mechanisms Linking Olfactory Impairment and Risk of Mortality. Front Neurosci. 2020 Feb 21;14:140. doi: 10.3389/fnins.2020.00140. eCollection 2020.
Results Reference
background
PubMed Identifier
34830550
Citation
Schambeck SE, Crowell CS, Wagner KI, D'Ippolito E, Burrell T, Mijocevic H, Protzer U, Busch DH, Gerhard M, Poppert H, Beyer H. Phantosmia, Parosmia, and Dysgeusia Are Prolonged and Late-Onset Symptoms of COVID-19. J Clin Med. 2021 Nov 12;10(22):5266. doi: 10.3390/jcm10225266.
Results Reference
background
PubMed Identifier
32167747
Citation
Baig AM, Khaleeq A, Ali U, Syeda H. Evidence of the COVID-19 Virus Targeting the CNS: Tissue Distribution, Host-Virus Interaction, and Proposed Neurotropic Mechanisms. ACS Chem Neurosci. 2020 Apr 1;11(7):995-998. doi: 10.1021/acschemneuro.0c00122. Epub 2020 Mar 13.
Results Reference
background
PubMed Identifier
32563019
Citation
Meng X, Deng Y, Dai Z, Meng Z. COVID-19 and anosmia: A review based on up-to-date knowledge. Am J Otolaryngol. 2020 Sep-Oct;41(5):102581. doi: 10.1016/j.amjoto.2020.102581. Epub 2020 Jun 2.
Results Reference
background
PubMed Identifier
32469400
Citation
Politi LS, Salsano E, Grimaldi M. Magnetic Resonance Imaging Alteration of the Brain in a Patient With Coronavirus Disease 2019 (COVID-19) and Anosmia. JAMA Neurol. 2020 Aug 1;77(8):1028-1029. doi: 10.1001/jamaneurol.2020.2125. No abstract available.
Results Reference
background
PubMed Identifier
32790835
Citation
Morbini P, Benazzo M, Verga L, Pagella FG, Mojoli F, Bruno R, Marena C. Ultrastructural Evidence of Direct Viral Damage to the Olfactory Complex in Patients Testing Positive for SARS-CoV-2. JAMA Otolaryngol Head Neck Surg. 2020 Oct 1;146(10):972-973. doi: 10.1001/jamaoto.2020.2366. No abstract available.
Results Reference
background
PubMed Identifier
33293264
Citation
Hawkes C. Parosmia: treatment, mechanism, and types. BMJ. 2020 Dec 8;371:m4739. doi: 10.1136/bmj.m4739. No abstract available.
Results Reference
background
PubMed Identifier
32937591
Citation
Brann DH, Tsukahara T, Weinreb C, Lipovsek M, Van den Berge K, Gong B, Chance R, Macaulay IC, Chou HJ, Fletcher RB, Das D, Street K, de Bezieux HR, Choi YG, Risso D, Dudoit S, Purdom E, Mill J, Hachem RA, Matsunami H, Logan DW, Goldstein BJ, Grubb MS, Ngai J, Datta SR. Non-neuronal expression of SARS-CoV-2 entry genes in the olfactory system suggests mechanisms underlying COVID-19-associated anosmia. Sci Adv. 2020 Jul 31;6(31):eabc5801. doi: 10.1126/sciadv.abc5801. Epub 2020 Jul 24.
Results Reference
background
PubMed Identifier
3927168
Citation
Pace U, Hanski E, Salomon Y, Lancet D. Odorant-sensitive adenylate cyclase may mediate olfactory reception. Nature. 1985 Jul 18-24;316(6025):255-8. doi: 10.1038/316255a0.
Results Reference
background
PubMed Identifier
8467526
Citation
Anholt RR. Molecular neurobiology of olfaction. Crit Rev Neurobiol. 1993;7(1):1-22.
Results Reference
background
PubMed Identifier
9754114
Citation
Levy LM, Henkin RI, Lin CS, Hutter A, Schellinger D. Increased brain activation in response to odors in patients with hyposmia after theophylline treatment demonstrated by fMRI. J Comput Assist Tomogr. 1998 Sep-Oct;22(5):760-70. doi: 10.1097/00004728-199809000-00019.
Results Reference
background
PubMed Identifier
12086637
Citation
Neumann S, Bradke F, Tessier-Lavigne M, Basbaum AI. Regeneration of sensory axons within the injured spinal cord induced by intraganglionic cAMP elevation. Neuron. 2002 Jun 13;34(6):885-93. doi: 10.1016/s0896-6273(02)00702-x.
Results Reference
background
PubMed Identifier
16181424
Citation
Moon C, Simpson PJ, Tu Y, Cho H, Ronnett GV. Regulation of intracellular cyclic GMP levels in olfactory sensory neurons. J Neurochem. 2005 Oct;95(1):200-9. doi: 10.1111/j.1471-4159.2005.03356.x.
Results Reference
background
PubMed Identifier
18377763
Citation
Henkin RI, Velicu I. cAMP and cGMP in nasal mucus: relationships to taste and smell dysfunction, gender and age. Clin Invest Med. 2008;31(2):E71-7. doi: 10.25011/cim.v31i2.3366.
Results Reference
background
PubMed Identifier
18377764
Citation
Henkin RI, Velicu I. cAMP and cGMP in nasal mucus related to severity of smell loss in patients with smell dysfunction. Clin Invest Med. 2008;31(2):E78-84. doi: 10.25011/cim.v31i2.3367.
Results Reference
background
PubMed Identifier
19359985
Citation
Henkin RI, Velicu I, Schmidt L. An open-label controlled trial of theophylline for treatment of patients with hyposmia. Am J Med Sci. 2009 Jun;337(6):396-406. doi: 10.1097/MAJ.0b013e3181914a97.
Results Reference
background
PubMed Identifier
27713276
Citation
Barnes PJ. Theophylline. Pharmaceuticals (Basel). 2010 Mar 18;3(3):725-747. doi: 10.3390/ph3030725.
Results Reference
background
PubMed Identifier
23165381
Citation
Henkin RI, Schultz M, Minnick-Poppe L. Intranasal theophylline treatment of hyposmia and hypogeusia: a pilot study. Arch Otolaryngol Head Neck Surg. 2012 Nov;138(11):1064-70. doi: 10.1001/2013.jamaoto.342.
Results Reference
background
Citation
Goldstein, M.F.; Hilditch, G.J.; Frankel, I.; Chambers, L.; Dvorin, D.J.; Belecanech, G. Intra-nasal theophylline for the treatment of chronic anosmia and hyposmia. Journal of Allergy & Clinical Immunology. 2017;139(2):AB252.
Results Reference
background
PubMed Identifier
28775001
Citation
Nigwekar SU, Weiser JM, Kalim S, Xu D, Wibecan JL, Dougherty SM, Mercier-Lafond L, Corapi KM, Eneanya ND, Holbrook EH, Brown D, Thadhani RI, Paunescu TG. Characterization and Correction of Olfactory Deficits in Kidney Disease. J Am Soc Nephrol. 2017 Nov;28(11):3395-3403. doi: 10.1681/ASN.2016121308. Epub 2017 Aug 3.
Results Reference
background
PubMed Identifier
34894449
Citation
Lee JJ, Peterson AM, Kallogjeri D, Jiramongkolchai P, Kukuljan S, Schneider JS, Klatt-Cromwell CN, Drescher AJ, Brunworth JD, Piccirillo JF. Smell Changes and Efficacy of Nasal Theophylline (SCENT) irrigation: A randomized controlled trial for treatment of post-viral olfactory dysfunction. Am J Otolaryngol. 2022 Mar-Apr;43(2):103299. doi: 10.1016/j.amjoto.2021.103299. Epub 2021 Dec 3.
Results Reference
background
PubMed Identifier
35797023
Citation
Lee JJ, Gupta S, Kallogjeri D, Piccirillo JF. Safety of High-Dose Nasal Theophylline Irrigation in the Treatment of Postviral Olfactory Dysfunction: A Dose-Escalation Study. JAMA Otolaryngol Head Neck Surg. 2022 Sep 1;148(9):885-886. doi: 10.1001/jamaoto.2022.1574.
Results Reference
background
PubMed Identifier
6463130
Citation
Doty RL, Shaman P, Dann M. Development of the University of Pennsylvania Smell Identification Test: a standardized microencapsulated test of olfactory function. Physiol Behav. 1984 Mar;32(3):489-502. doi: 10.1016/0031-9384(84)90269-5.
Results Reference
background
PubMed Identifier
1593914
Citation
Ware JE Jr, Sherbourne CD. The MOS 36-item short-form health survey (SF-36). I. Conceptual framework and item selection. Med Care. 1992 Jun;30(6):473-83.
Results Reference
background
PubMed Identifier
20526405
Citation
Busner J, Targum SD. The clinical global impressions scale: applying a research tool in clinical practice. Psychiatry (Edgmont). 2007 Jul;4(7):28-37.
Results Reference
background
PubMed Identifier
28653978
Citation
Dunlop BW, Gray J, Rapaport MH. Transdiagnostic Clinical Global Impression Scoring for Routine Clinical Settings. Behav Sci (Basel). 2017 Jun 27;7(3):40. doi: 10.3390/bs7030040.
Results Reference
background
PubMed Identifier
29719139
Citation
Mattos JL, Schlosser RJ, Mace JC, Smith TL, Soler ZM. Establishing the minimal clinically important difference for the Questionnaire of Olfactory Disorders. Int Forum Allergy Rhinol. 2018 Sep;8(9):1041-1046. doi: 10.1002/alr.22135. Epub 2018 May 2.
Results Reference
background
PubMed Identifier
3816016
Citation
Moscucci M, Byrne L, Weintraub M, Cox C. Blinding, unblinding, and the placebo effect: an analysis of patients' guesses of treatment assignment in a double-blind clinical trial. Clin Pharmacol Ther. 1987 Mar;41(3):259-65. doi: 10.1038/clpt.1987.26.
Results Reference
background
PubMed Identifier
34291813
Citation
O'Byrne L, Webster KE, MacKeith S, Philpott C, Hopkins C, Burton MJ. Interventions for the treatment of persistent post-COVID-19 olfactory dysfunction. Cochrane Database Syst Rev. 2021 Jul 22;7(7):CD013876. doi: 10.1002/14651858.CD013876.pub2.
Results Reference
background
PubMed Identifier
28040824
Citation
Sorokowska A, Drechsler E, Karwowski M, Hummel T. Effects of olfactory training: a meta-analysis. Rhinology. 2017 Mar 1;55(1):17-26. doi: 10.4193/Rhino16.195.
Results Reference
background
PubMed Identifier
31318413
Citation
Whitcroft KL, Hummel T. Clinical Diagnosis and Current Management Strategies for Olfactory Dysfunction: A Review. JAMA Otolaryngol Head Neck Surg. 2019 Sep 1;145(9):846-853. doi: 10.1001/jamaoto.2019.1728.
Results Reference
background
PubMed Identifier
29901865
Citation
Nguyen TP, Patel ZM. Budesonide irrigation with olfactory training improves outcomes compared with olfactory training alone in patients with olfactory loss. Int Forum Allergy Rhinol. 2018 Sep;8(9):977-981. doi: 10.1002/alr.22140. Epub 2018 Jun 14.
Results Reference
background
PubMed Identifier
29879268
Citation
Tait S, Kallogjeri D, Suko J, Kukuljan S, Schneider J, Piccirillo JF. Effect of Budesonide Added to Large-Volume, Low-pressure Saline Sinus Irrigation for Chronic Rhinosinusitis: A Randomized Clinical Trial. JAMA Otolaryngol Head Neck Surg. 2018 Jul 1;144(7):605-612. doi: 10.1001/jamaoto.2018.0667.
Results Reference
background
PubMed Identifier
23895713
Citation
Menorca RM, Fussell TS, Elfar JC. Nerve physiology: mechanisms of injury and recovery. Hand Clin. 2013 Aug;29(3):317-30. doi: 10.1016/j.hcl.2013.04.002.
Results Reference
background
PubMed Identifier
35115994
Citation
Wei G, Gu J, Gu Z, Du C, Huang X, Xing H, Li L, Zhang A, Hu X, Huo J. Olfactory Dysfunction in Patients With Coronavirus Disease 2019: A Review. Front Neurol. 2022 Jan 18;12:783249. doi: 10.3389/fneur.2021.783249. eCollection 2021.
Results Reference
background
PubMed Identifier
34752471
Citation
Jafar A, Lasso A, Shorr R, Hutton B, Kilty S. Olfactory recovery following infection with COVID-19: A systematic review. PLoS One. 2021 Nov 9;16(11):e0259321. doi: 10.1371/journal.pone.0259321. eCollection 2021.
Results Reference
background
PubMed Identifier
35797024
Citation
Gupta S, Lee JJ, Perrin A, Khan A, Smith HJ, Farrell N, Kallogjeri D, Piccirillo JF. Efficacy and Safety of Saline Nasal Irrigation Plus Theophylline for Treatment of COVID-19-Related Olfactory Dysfunction: The SCENT2 Phase 2 Randomized Clinical Trial. JAMA Otolaryngol Head Neck Surg. 2022 Sep 1;148(9):830-837. doi: 10.1001/jamaoto.2022.1573.
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Smell in Covid-19 and Efficacy of Nasal Theophylline

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