The effect of COVID-19 on nasal mucociliary clearance

BACKGROUND

The impacts of coronavirus disease-2019 (COVID-19) on nasal mucociliary clearance (MCC) have shown conflicting results.

OBJECTIVES

The aim of this study was to determine whether COVID-19 infections affect nasal mucociliary activity using the saccharin test to measure nasal MCC time.

MATERIAL AND METHODS

This prospective comparative investigation included 25 patients with COVID-19 infection and 25 healthy controls. The nasal MCC time was assessed using the saccharin test. Saccharin test was applied to COVID-19 patients between the 10th and 20th days of COVID-19 test positivity. Patients admitted to the otolaryngology outpatient clinic with non-nasal symptoms and no history of COVID-19 infection served as the control subjects.

RESULTS

Age, gender distribution, smoking, and alcohol usage, and the existence of other systemic disorders had no statistically significant differences between the groups (p = 0.25, p = 0.77, p = 1.00, p = 0.28, p = 0.54, respectively). The COVID-19 group had a mean nasal MCC time of 12.00 ± 2.51 min, compared to 9.77 ± 2.51 min in the control group. The nasal MCC time in the COVID-19 group was statistically significantly longer (p = 0.043).

CONCLUSIONS AND SIGNIFICANCE

The COVID-19 infection negatively affects mucociliary activity and causes prolongation of MCC. As the nasal defense mechanism weakens in the early period after COVID-19 infection, susceptibility to respiratory infections may occur.

Saccharin test: Methodological validation and systematic review of the literature

OBJECTIVES

Saccharin test (ST) is a convenient method to assess the efficiency of mucociliary clearance, the primary defense mechanism of the upper airways' tract. The study objectives are to: (1) substantiate its short- (3 days) and long-term (30 days) repeatability; (2) assess its tolerability; (3) conduct a systematic literature review and to compare our results with the existing evidence.

METHODS

Twenty-nine healthy subjects were enrolled in an observational prospective study to perform an ST on three separate visits (at baseline; at follow-up visits at day 3 and at day 30). Transit times were recorded and self-reported nasal and general symptoms noted. A systematic review of the literature was conducted to compare our results with the existing literature.

RESULTS

The mean values (±SD) of ST transit time (STTT) were 7.085 (±2.19), 7.788 (±2.11), and 7.790 (±2.06) minutes at baseline, day 3, and day 30, respectively. Significant linear regression analysis was observed between day 3 and baseline (r = .193; P = .019) and day 30 and baseline (r = .182 P = .024). Significant agreement for the intrasession repeatability was observed with an ICC = .354 (P = .001). Outcomes' comparisons between baseline vs day 3 (P = .197) and baseline vs day 30 (P = .173) were not statistically significant. ST was well tolerated. Concordance with existing literature's data and high level of STTT repeatability were confirmed by the qualitative analysis.

CONCLUSION

STTT reproducibility was good both in the short- and long-term. ST tolerability was very good. Our study data are consistent with the existing literature, indicating ST as a sound methodology for detection of early respiratory health changes and for specific regulatory application in respiratory research.

Impact of exclusive e-cigarettes and heated tobacco products use on muco-ciliary clearance

Background:

Tobacco smoking impairs mucociliary clearance (MCC) efficiency as shown by prolonged saccharin test transit time (STTT). Avoiding exposure to tobacco smoke from combustible cigarettes may restore MCC function and former smokers have been shown to exhibit similar STTT as never smokers. The impact on STTT of switching from smoking to combustion-free tobacco products such as e-cigarettes (ECs) and heated tobacco products (HTPs) is not known.

Methods:

We report STTT of exclusive EC and HTP users. Test results were compared with those obtained in current, former, and never smokers.

Results:

STTT were obtained from 39 current, 40 former, 40 never smokers, and from 20 EC and 20 HTP users. Comparison of STTT values showed significant difference among the five study groups (p < 0.00001) with current smokers having a median [interquartile range (IQR)] STTT of 13.15 min, which was significantly longer compared with that of all other study groups. In particular, compared with former (7.26 min) and never smokers (7.24 min), exclusive EC users and exclusive HTP users had similar STTT at 7.00 and 8.00 min, respectively.

Conclusion:

Former smokers who have switched to exclusive regular use of combustion-free nicotine delivery systems (i.e., ECs and HTPs) exhibit similar saccharin transit time as never and former smokers. This suggests that combustion-free nicotine delivery technologies are unlikely to have detrimental effects on MCC function.

The Effect of Passive Smoking on Mucociliary Clearance and Inferior Concha Reactivity

INTRODUCTION

The aim of this study is to investigate the effect of cigarette smoke on turbinate reactivity and mucociliary clearance (MCC) in passive smokers.

METHODS

60 adult patients (30 passive smokers and 30 healthy subjects as the control group) were recruited for this study. Following a questionnaire on passive smoke exposure, MCC measurement using the saccharin test was carried out to all participants. The baseline and after decongestant acoustic rhinometry values (MCA1, MCA2, VOL1, VOL2) were measured and the percentage changes between the two test values (ie; response to nasal decongestants = concha reactivity) were recorded.

RESULTS

All 60 patients, including 37 women (61.7%) and 23 men (38.3%) were between 18-57 years of age . MCC's average measurements were 11.13 minutes in the passive smokers group, 7.87 minutes in the control group, which was statistically significantly different (p < 0.05). There was a statistically significant difference between the passive smokers and control group for acoustic rhinometric measurement of the ratio of MCA2 and VOL2 values before and after decongestant application (p < 0.05).

DISCUSSION

Passive smoking can damage the nasal mucosa at least as active smoking. The number of studies on this subject is limited. There are no studies in the literature showing the effect of cigarette smoke on the inferior turbinate mucosal response. In our study, the inferior turbinate decongestant capacity was found to be significantly decreased in the passive smokers compared to the control group.

CONCLUSION

As a result of cigarette exposure, the erectile function of the lower turbines may be impaired. The task of the ENT physicians is to warn the passive smokers in this regard.

Short and Long Term Repeatability of Saccharin Transit Time in Current, Former, and Never Smokers

Smoking progressively damages the efficiency of mucociliary clearance (MCC) defense mechanisms, thus contributing to increased susceptibility to respiratory infections. Prolonged mucociliary clearance transit time (MCCTT) caused by chronic smoking has been investigated by saccharin test, but little data is available about its short- and long-term reproducibility. Moreover, it is not known if MCC impairment can be reversed when stopping smoking. Objective of the study is to investigate and compare short (3 days) and long term (30 days) repeatability of baseline saccharin transit time (STT) among current, former, and never smokers. STT results were analyzed in 39 current, 40 former, and 40 never smokers. Significant (p < 0.0001) short-term and long-term repeatability of STT were observed in current (R squared = 0.398 and 0.672, for short- and long-term, respectively) and former smokers (R squared = 0.714 and 0.595, for short- and long-term, respectively). Significant differences in MCCTT were observed among the three study groups (p < 0.0001); the median (IQR) MCCTT being 13.15 (10.24–17.25), 7.26 (6.18–9.17), and 7.24 (5.73–8.73) minutes for current, former and never smokers, respectively. Comparison between current smokers and former smokers was significantly different (p < 0.0001). There was no significant difference between former and never smokers. The Saccharin test was well tolerated by all participants. We have shown for the first time high level repeatability in both current and former smokers. Moreover, MCC impairment can be completely reversed, former smokers exhibiting similar STT as never smokers. Measurement of STT is a sensitive biomarker of physiological effect for the detection of early respiratory health changes and may be useful for clinical research.

The effect of premature ovarian insufficiency on nasal mucociliary clearance time

Premature ovarian insufficiency (POI) is a global health concern for women and affects several systems, such as cardiovascular system, autoimmune disease, and psychological status. The aim of this study was to investigate the effect of POI on nasal mucociliary clearance time via saccharin test by comparing postmenopausal women and healthy controls. Thirty-five (35) patients with POI, 35 healthy postmenopausal women and 35 healthy controls were recruited in this study. All study participants underwent measurements of nasal mucociliary clearance time via saccharine test. When women with POI and postmenopausal women compared with the controls, nasal mucociliary clearance time was longer in both women with POI and postmenopausal women. When women with POI were compared with postmenopausal women, the nasal mucociliary clearance time was not difference between two groups. There was a significant prolonged nasal mucociliary clearance time in the women with POI and postmenopausal women. Lower serum estradiol levels in women with POI as well as postmenopausal women had an adverse effect of nasal mucociliary clearance time.

Comparison of Nasal Mucociliary Function before and after Septorhinoplasty Surgery Using Saccharin Test

Background

This study was carried out to compare mucociliary function (MCF) of nasal cavity before and after septorhinoplasty surgery by saccharin test.

Materials and Methods

This study was carried out on 70 patients who needed septorhinoplasty surgery in Kashani and Alzahra Hospital during 2013-2014 to measure MCF. Saccharin test was performed on the patients before surgery and on three more intervals 1 day, 1 week, and on month after ward and the readings were recorded. Saccharin test is performed by placing saccharin granules on the anterior part of inferior turbinate and the time the patient feels the sweet taste is recorded the normal range is below 30 min.

Results

Mean of test for each time interval was obtained and comparison of measurements was made reading were mean of saccharin test before surgery (7.74 ± 1.65 min) the day after surgery (7.75 ± 1.7 min), on week after surgery (15.04 ± 3.4), and 1 month after surgery (8.49 ± 2.08 min). The readings before surgery did not have statistically significant difference with the readings 1 day after surgery P = 0.99, but comparison of test results at other time intervals were significant (P < 0.001). A relative increase in saccharin test time was seen in a period of 1 month after surgery the rise was more noticeable in the 1^st week compared to 1 month after surgery.

Conclusion

This study in the period after septorhinoplasty surgery MCF undergoes slight impairment that gradually progresses to normal values during 1 month after surgery.

Effect of cigarette smoking on nasal mucociliary clearance: A comparative analysis using saccharin test

Background:

Nasal mucociliary clearance (NMC) system transports the mucus layer covering the nasal epithelium towards nasopharynx by ciliary beating at a frequency of 7-16 Hz. NMC is altered by septal deviations, upper respiratory infections, and drugs. Few studies have revealed significant depression of ciliary activity in smokers. We conducted this study to compare NMC and influence duration of smoking on NMC in adult smokers and nonsmokers using saccharin test.

Materials and Methods:

Our study included 30 nonsmokers and 30 smokers (21-40 years) who were not on any medications and had no history of any systemic illness. Time elapsing until the first experience of sweet taste at posterior nasopharynx, following placement of saccharin particle approximately 1 cm behind the anterior end of inferior turbinate was recorded as NMC time in minutes using standard method described by Anderson. Mean NMC of both groups were compared using Student's t-test and influence of duration was analyzed by one-way Analysis of variance (ANOVA).

Results:

NMC was significantly prolonged in smokers (481.2 ± 29.83; P < 0.01) in comparison to nonsmokers (300.32 ± 17.42 s). A statistically significant increase in NMC was observed with an increase in duration of smoking habit (NMC in smoking <1 year = 492.25 ± 79.93 s, 1-5 years = 516.7 ± 34.01 s, >5 years = 637.5 ± 28.49 s; F statistic = 20.8968, P = 0.0000).

Conclusions:

NMC measurement is a simple and useful index for the assessment of effect of smoking on the ciliary activity of respiratory mucosa. Prolonged clearance observed in smokers of our study may be due to slowed ciliary beat frequency or reduction in number of cilia and changes in viscoelastic properties of mucus.

Evaluation of mucociliary clearance among women using biomass and clean fuel in a periurban area of Chennai: A preliminary study

Background:

Nasal mucociliary clearance (NMC) plays a crucial role in the defense of the airways against inhaled substances and is affected by various factors. The effect of particulate matter on NMC in women using biomass fuel has not been well studied.

Aim:

This cross-sectional study was conducted to assess the NMC time in biomass fuel users and compare it with that of clean fuel users.

Materials and Methods:

NMC time and Peak Expiratory Flow Rate (PEFR) were determined in women of age ranging from 18 to 45 years using biomass fuel (n=30) and clean fuel (n=30). The time taken to perceive the sweet taste, following placement of saccharin 1 cm behind the anterior end of inferior turbinate was recorded as NMC time. PEFR was measured using mini-Wright peak flow meter. Comparison between groups was analyzed using t-test and ANOVA in R statistical software.

Results:

NMC time was significantly prolonged in biomass fuel users (765.8 ± 378.16 s) in comparison to clean fuel users (545.4 ± 215.55 s). PEFR was significantly reduced (319.3 l/min) in biomass fuel users compared to clean fuel users (371.7 l/min). Women from lower socioeconomic status, lower literacy status, older undernourished women and women cooking for>15 years had prolonged Saccharin Transit Time (STT) and reduced PEFR.

Conclusions:

This study highlights the effects of indoor air pollution on respiratory defense mechanism. This simple noninvasive, inexpensive, screening test can be used as an early indicator of respiratory damage caused by exposure to air pollutants.