Background: Chronic obstructive pulmonary disease (COPD) is a devastating illness that affects 4.3% of the population of British Columbia over the age of 45 years. Asthma is known to coexist in 10-20% of individuals with obstructive lung disease, and adds to the substantial burden of illness posed by COPD alone. Inhaled corticosteroids (ICS) are currently recommended for the management of COPD among individuals with frequent exacerbations; however, the ability of inhaled corticosteroids to reduce death and hospitalizations among individuals with COPD is controversial. Less is known about the effectiveness of ICS among individuals who are afflicted with both COPD and asthma. Methods: We used a retrospective cohort study design and administrative data to estimate the relative effectiveness of ICS in reducing hospitalizations or death among individuals with concomitant asthma and COPD, compared with individuals with COPD alone. We used an extended Cox model to estimate this association, with a time-varying measure of exposure to ICS. Results: We did not find any association between ICS and hazard of death or hospitalization among individuals with COPD alone (HR = 0.99; 95% CI: 0.94 – 1.05), however the hazard was 18% lower (HR = 0.82; 95% CI: 0.69-0.99) among individuals with concomitant disease. Conclusions: Individuals with combined COPD and asthma show significant benefit from the use of ICS and are more responsive to the effects of ICS than individuals with COPD alone.

Corticosteroids are the most potent and reliable of the available agents among the anti-inflammatory drugs, and have assumed a major role in the management of asthma. This has subsequently resulted in the global widespread use of inhaled corticosteroids (ICS). A variety of studies have been undertaken to examine the effects of ICS on voice production among people with asthma. Most research suggests that the long-term use of ICS has a negative effect on voice production. However, the results of these studies are limited because of the reliance upon examining an asthmatic population and not consistently recording the dose prescribed. As a result, one cannot exclude that some of the voice problems may have been previously caused by asthma and thus, the contributing effects of ICS are obscured. Therefore, an ideal approach to examine the influence of ICS on voice is to test its short-term effects on healthy individuals, using a specific ICS (Fluticasone Propionate) at a fixed dose (1000 µg/Day). Thirty healthy adults (15 females & 15 males) aged between 18 to 30 years participated in this study. All participants were non-smokers with no history of speech, language or voice disorder. No participants had a history of asthma, respiratory illness hospital admission or inhaler use within the past 3 months. All participants followed the treatment regime often prescribed by physicians (in Canterbury region) for treating asthma (500 µg in morning & 500 µg in evening). Each participant self administered (inhaled) two puffs of ICS in the morning and again in the evening over a six day period. Voice samples were audio-recorded prior to undergoing the ICS regime, at various points during the ICS regime, and at the conclusion of ICS regime. Each participant’s audio-recorded samples were submitted for acoustic analysis using a commercially available speech analysis system (CSL 4300B, Kay Elemetrics, 1994). Three measures were performed, (1) vocal fundamental frequency (F0), (2) long-time spectral analysis (LTAS) and (3) formant frequency and formant frequency bandwidth. The results of this study indicate that ICS does have an effect on acoustic properties of voice. These effects were more evident in connected speech compared to isolated vowel productions. In particular, the spectral tilt and first spectral peak of continuous speech samples were found to change from baseline. The current results are discussed in regard to the phonatory deterioration associated with ICS use. The present study provides a framework for developing ICS treatment for respiratory disease in the phase of minimizing adverse effects on voice.

Background: Chronic obstructive pulmonary disease (COPD) is a devastating illness that affects 4.3% of the population of British Columbia over the age of 45 years. Asthma is known to coexist in 10-20% of individuals with obstructive lung disease, and adds to the substantial burden of illness posed by COPD alone. Inhaled corticosteroids (ICS) are currently recommended for the management of COPD among individuals with frequent exacerbations; however, the ability of inhaled corticosteroids to reduce death and hospitalizations among individuals with COPD is controversial. Less is known about the effectiveness of ICS among individuals who are afflicted with both COPD and asthma. Methods: We used a retrospective cohort study design and administrative data to estimate the relative effectiveness of ICS in reducing hospitalizations or death among individuals with concomitant asthma and COPD, compared with individuals with COPD alone. We used an extended Cox model to estimate this association, with a time-varying measure of exposure to ICS. Results: We did not find any association between ICS and hazard of death or hospitalization among individuals with COPD alone (HR = 0.99; 95% CI: 0.94 – 1.05), however the hazard was 18% lower (HR = 0.82; 95% CI: 0.69-0.99) among individuals with concomitant disease. Conclusions: Individuals with combined COPD and asthma show significant benefit from the use of ICS and are more responsive to the effects of ICS than individuals with COPD alone.

Background: Chronic obstructive pulmonary disease (COPD) is a devastating illness that affects 4.3% of the population of British Columbia over the age of 45 years. Asthma is known to coexist in 10-20% of individuals with obstructive lung disease, and adds to the substantial burden of illness posed by COPD alone. Inhaled corticosteroids (ICS) are currently recommended for the management of COPD among individuals with frequent exacerbations; however, the ability of inhaled corticosteroids to reduce death and hospitalizations among individuals with COPD is controversial. Less is known about the effectiveness of ICS among individuals who are afflicted with both COPD and asthma. Methods: We used a retrospective cohort study design and administrative data to estimate the relative effectiveness of ICS in reducing hospitalizations or death among individuals with concomitant asthma and COPD, compared with individuals with COPD alone. We used an extended Cox model to estimate this association, with a time-varying measure of exposure to ICS. Results: We did not find any association between ICS and hazard of death or hospitalization among individuals with COPD alone (HR = 0.99; 95% CI: 0.94 – 1.05), however the hazard was 18% lower (HR = 0.82; 95% CI: 0.69-0.99) among individuals with concomitant disease. Conclusions: Individuals with combined COPD and asthma show significant benefit from the use of ICS and are more responsive to the effects of ICS than individuals with COPD alone. / Medicine, Faculty of / Population and Public Health (SPPH), School of / Graduate

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal

This thesis is part of a larger series of studies being conducted by Kristine Tanner, PhD, Associate Professor in the Department of Communication Disorders at Brigham Young University (BYU). The larger project is funded by the National Institute on Deafness and Other Communication Disorders at the National Institutes of Health. This thesis primarily investigated the effects of combination inhaled corticosteroids (ICs) on aerodynamic measures of the voice. In recent years, an increase in the localized laryngeal side effects from IC treatment, including dysphonia, have been reported. This study employed a between-groups experimental design, with two groups of rabbit larynges having been exposed to either ICs or nebulized isotonic saline two times each day for eight weeks at The University of Utah. For this study, the independent variable is group condition (i.e., IC versus saline) and the dependent variables are two aerodynamic measurements made at the onset of phonation using a benchtop experimental setup, namely phonation threshold pressure (PTP; cmH2O) and phonation threshold flow (PTF; L/min). The results of this study indicate a significant difference in PTP and PTF between vocal folds treated with IC as compared to vocal folds treated with nebulized isotonic saline solution. Implications of this study suggest negative changes in the voice due to IC treatment.

The purpose of this thesis is to examine the effects of inhaled corticosteroid drugs (ICs) on the voice due to their frequent use in treating an increasing prevalence of asthma disorders. As part of a larger five-year study, the focus of this thesis is specifically on whether 8 weeks of in vivo exposure to ICs will cause changes in the sustained subglottal pressure, sustained airflow, and visual-perceptual ratings of edema and erythema in excised rabbit larynges. Researchers administered either ICs or a control nebulized isotonic saline solution to 22 rabbits in vivo, sacrificed them, and harvested their larynges for benchtop research. While ensuring proper tissue preservation, researchers then finely dissected the larynges to expose the true vocal folds and run phonation trials. Dependent variables included continuous acoustic signals (Hz), subglottal pressure (cm H2O), and airflow (L/min) data for 15 phonation trials per rabbit larynx. Researchers also collected still image photographs at this time and subsequently normalized them for use in the visual-perceptual portion of this thesis. For visual-perceptual ratings, raters used a 0-3 equal appearing interval scale to rate aspects of edema and erythema on left and right vocal fold and arytenoid tissues. Results indicate that, when compared to control larynges exposed to nebulized isotonic saline, experimental larynges treated with ICs require significantly higher subglottal pressure to maintain phonation, p < .05. Mean sustained phonation for experimental larynges is 11.24 cm H2O compared to 8.92 cm H2O for that of control larynges. Phonation trials for experimental larynges have significantly higher sustained airflow with a mean of 0.09 L/min compared to 0.07 L/min for that of control larynges, p < .05. Surprisingly, experimental larynges have higher average fundamental frequencies with less variability (mean: 519 Hz, standard deviation: 66 Hz) than that of control larynges (mean: 446 Hz, standard deviation: 130 Hz). On visual-perceptual ratings, experimental larynges have significantly higher severity ratings on all eight items rated, p < .0001 - p = .0305. Based on these results, it is concluded that ICs cause significant damage to rabbit vocal folds, as evidenced by higher sustained pressure, higher airflow, and higher severity ratings for experimental versus control larynges. The dependent variables in this thesis are novel in benchtop model research and demonstrate a unique perspective on this research question. Thus, this thesis informs future phonation, benchtop, and visual-perceptual research.

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第18852号 / 医博第3963号 / 新制||医||1007(附属図書館) / 31803 / 京都大学大学院医学研究科医学専攻 / (主査)教授 伊達 洋至, 教授 中原 俊隆, 教授 山田 亮 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

The purpose of this thesis is to investigate the reversibility of the adverse effects of combination inhaled corticosteroids (ICs) on vocal fold health as part of a five-year study. This pilot study tested the hypothesis that the adverse effects of ICs may be induced and then reversed, using a benchtop model and rabbit larynges measuring sustained subglottic pressure and airflow. Eighteen rabbits were assigned randomly to 5 subgroups, including baseline, induction experimental, induction control, reversibility experimental, and reversibility control. Baseline rabbits did not receive any treatment. Both experimental groups, induction and reversibility, were administered Advair until visual-perceptual ratings were noted. Their paired control groups were administered nebulized saline in the same dosage levels. Induction groups were immediately sacrificed, while reversibility groups entered a withdrawal phase until visual-perceptual ratings showed a return to baseline. Larynges were dissected and mounted on a benchtop model for phonation trials. Dependent variables included sustained phonatory pressure (cm/H2O) and sustained phonatory airflow (L/min). The results of phonation trials indicate that sustained pressure and flow were higher for both induction and reversibility experimental groups when compared to baseline and control groups. The reversibility experimental group had lower sustained pressure and flow than the induction experimental group. These results indicate a reduction of signs after a period of rest. These findings suggest that voice symptoms may be reversible to a degree after combination IC use. These are important preliminary data that support future studies with larger sample sizes to confirm findings.