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Jaclyn Smith

Publications and source records attributed to Jaclyn Smith.

4 recordsLinked to original sources
PubMed2006

Ambulatory methods for recording cough.

Recording cough sounds to objectively quantify coughing was first performed using large reel-to-reel tape recorders more than 40 years ago. Coughs were counted manually, which is an extremely laborious and time-consuming process. Current technologies including digital recording techniques, data compression and improvements in digital storage capacity should make the process of recording and counting coughs suitable for automation; however, to date no accurate, objective cough monitoring device is available. Cough sounds are easily distinguishable from other vocalizations by the human ear and hence it is reasonable to assume that coughs sounds should have characteristic, identifying acoustic properties. However, the acoustic features of spontaneously occurring cough sounds are extremely variable. Furthermore, in even the worst cases of cough, the time spent speaking is an order of magnitude greater than the time spent coughing. It follows that even an algorithm that mistakes only a very small proportion of speech as cough will still have an unacceptable false positive rate. There is a clear need for an objective measure of cough for use in clinical practice, clinical research and trials of novel treatments. In the near future automated ambulatory systems with sufficient accuracy to be of clinical use should be available.

Acoustics↗
PubMed2006

Effect of codeine on objective measurement of cough in chronic obstructive pulmonary disease.

BACKGROUND: Codeine is the standard antitussive treatment to which novel agents are compared. Little is known about the objective effect of any treatments on cough in chronic obstructive pulmonary disease (COPD). OBJECTIVE: To quantify the effect of codeine on objective cough frequency (quantified as time spent coughing: cough seconds, cs/h), citric acid cough threshold, and subjective measures in a double-blind, placebo-controlled crossover study in COPD. METHODS: We studied 21 patients with physician-diagnosed, stable disease who complained of cough (76.9% male; mean age, 67.7 years; mean predicted FEV(1), 53.4%; median smoking history, 43.5 pack-years). Each subject performed a cough challenge (single breath, citric acid), 10-hour daytime ambulatory and overnight cough recordings, subjective cough scores, and visual analog scales at baseline and on 2 study days, 1 week apart. Codeine phosphate 60 mg or matched placebo were given, in random order, at the start of each cough recording (0 and 12 hours). RESULTS: Median time spent coughing at baseline was 8.27 cs/h (interquartile range [IQR], 5.94-11.67); after placebo treatment, 7.22 cs/h (IQR 4.42-10.40); and after codeine treatment, 6.41 cs/h (IQR 3.86-9.10). Codeine treatment had a significant effect on time spent coughing compared with baseline (P = .02) but not compared with placebo (P = .52). There were no significant differences in cough challenge thresholds (log concentration of tussive agent causing 2 coughs or log concentration of tussive agent causing 5 coughs) or subjective cough measures for codeine compared with placebo. CONCLUSION: In this study, codeine was no more effective than placebo in patients with COPD complaining of cough. CLINICAL IMPLICATIONS: Codeine is the antitussive agent to which we compare new treatments; however, in a group of stable patients with COPD, it had no effect on cough frequency over placebo.

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PubMed2006

Cough in COPD: correlation of objective monitoring with cough challenge and subjective assessments.

BACKGROUND: The relationships between objective cough rates, cough reflex sensitivity, subjective estimates of cough frequency, and cough-related quality of life in patients with COPD are poorly understood. SUBJECTS: Twenty-six patients with stable COPD who complained of cough (76.9% men; mean +/- SD age, 68.7 +/- 6.9 years; mean FEV(1), 54.2 +/- 12.0% of predicted; median smoking history, 42.4 pack-years [range, 13 to 135 pack-years]). METHODS: Subjects performed a cough challenge test, ambulatory daytime and overnight sound recordings, scored the severity of cough (0 to 5 score and visual analog scale) for each recording period, and completed a cough-specific quality of life questionnaire (CQLQ). Coughs were counted manually and quantified in terms of cough seconds per hour (cs/h): the number of seconds within the recording that contain cough. RESULTS: Overall median time spent coughing was 7.5 cs/h (range, 2.7 to 23.1 cs/h; daytime median, 12.4 cs/h [range, 3.3 to 40.4 cs/h]; overnight, 1.9 cs/h [0.0 to 19.0 cs/h]) [p = <0.01]. Median log concentration of citric acid eliciting five coughs (C5) was - 0.9 mol/L (range, - 1.5 to 0.0 mol/L). Day time but not overnight time spent coughing was significantly correlated with log C5 (log C5 r = - 0.49, p = 0.02, and r = - 0.20, p = 0.37, respectively). Subjective cough scores and visual analog scales were moderately associated with objective time spent coughing: daytime (r = 0.37, p = 0.03, and r = 0.41, p = 0.03) and overnight (r = 0.48, p = <0.01, and r = 0.5, p = 0.01), respectively. CONCLUSIONS: Subjective measures of cough and cough reflex sensitivity are statistically related to time spent coughing in patients with COPD, but with low-to-moderate levels of correlation. These measures have insufficient predictive value to substitute for objective time spent coughing; however, in conjunction with the CQLQ, they may provide a qualitative dimension to the assessment of cough.

Aged↗