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(Chest. 2004;125:482-488.)
© 2004 American College of Chest Physicians

Gender Differences in Health-Related Quality of Life in Patients Complaining of Chronic Cough*

Cynthia T. French, MS; Kenneth E. Fletcher, PhD and Richard S. Irwin, MD, FCCP

* From the Departments of Medicine (Ms. French and Dr. Irwin) and Psychiatry (Dr. Fletcher), University of Massachusetts Medical School, Worcester, MA.

Correspondence to: Richard S. Irwin, MD, FCCP, University of Massachusetts Medical School, Division of Pulmonary, Allergy, and Critical Care Medicine, 55 Lake Ave North, Worcester, MA 01655; e-mail: IrwinR{at}ummhc.org


   Abstract
TOP
 Abstract
Introduction
 Materials and Methods
 Results
 Discussion
 Conclusion
 References
 
Study objectives: To confirm that more women than men who complain of chronic cough seek medical attention, to determine whether the health-related quality of life (HRQOL) of these women is more adversely affected than men, and to determine whether there are gender differences in the ways that chronic cough adversely affects HRQOL.

Design: Analysis of previously, prospectively collected data, but not previously analyzed or reported data, plus additional prospectively collected data to enrich the database to make meaningful gender comparisons.

Setting: Cough clinic in an academic, tertiary care medical center.

Participants: Subjects seeking medical attention complaining of cough of at least 8 weeks duration and a control group of smokers not complaining of cough.

Measurements: Assessment of chronic cough on HRQOL utilizing a valid and reliable cough-specific HRQOL instrument, the cough-specific quality-of-life questionnaire (CQLQ).

Interventions: All subjects completed the CQLQ prior to any contact with the cough specialist and medical intervention.

Results: In the original cohort of subjects, women (116 subjects) outnumbered the men (38 subject) by 3:1 (p < 0.0001). In the current study, total CQLQ scores for women were higher than for men (67.1 vs 59.7, respectively; p = 0.002). Women had higher scores than men in three of six subscales, as follows: physical complaints (21.6 vs 19.0, respectively; p = 0.004); psychosocial issues (14.7 vs 12.9, respectively; p = 0.002); and extreme physical complaints (8.9 vs 6.6, respectively; p < 0.001). Men and women had similar scores on the remaining subscales. Women scored significantly higher on 10 of the 28 items that make up the six subscales. The item that showed the greatest disparity and the most significant difference between women and men was wetting the pants (p < 0.001) as a result of chronic coughing.

Conclusions: Women with chronic cough were probably more inclined to seek medical attention than men because their HRQOL was more adversely affected and because they were more apt to suffer from physical complaints such as stress incontinence, which provoked psychosocial issues such as becoming embarrassed.

Key Words: chronic cough • gender differences in chronic cough • gender differences in cough and quality of life • health-related quality of life • quality of life


   Introduction
TOP
 Abstract
 Introduction
Materials and Methods
 Results
 Discussion
 Conclusion
 References
 
Prospective studies have revealed that the health-related quality of life (HRQOL) of patients complaining of chronic cough is adversely affected, and, that this is the most likely reason for why chronic cough is one of the most frequent complaints for which patients seek medical care from pulmonologists.1 2 Although multiple prospective studies of patients complaining of chronic cough due to a variety of diseases also have shown that chronic cough is nearly consistently more common in women than men,3 it is not known why. While tussigenic inhalation challenges have shown that healthy women4 and women with chronic cough5 have lower cough thresholds than healthy men and men with chronic cough, it is not known whether this finding of higher cough reflex sensitivity or other factors such as a coughing causing a greater adverse effect on HRQOL can explain why women more commonly seek medical attention because of chronic cough. Consequently, we sought the following: (1) to confirm that more women than men complaining of chronic cough seek medical attention, (2) to determine whether the HRQOL of women with chronic cough who seek medical attention is more adversely affected than men, and (3) to determine whether there are differences in the ways that chronic cough adversely affects the HRQOL of women and men.


   Materials and Methods
TOP
 Abstract
 Introduction
 Materials and Methods
Results
 Discussion
 Conclusion
 References
 
We performed a post hoc analysis of data collected prospectively2 during psychometric testing of the cough quality-of-life questionnaire (CQLQ) in a control group of 31 smokers who were observed to be coughing but were not complaining of cough, and in 154 consecutive and unselected patients complaining of chronic cough (ie, the original cohort) who were seeking medical attention in the cough clinic of our academic, tertiary care, medical center. Chronic cough was defined as a cough of at least 8 weeks duration. In order to improve our ability to make gender comparisons, an additional 18 consecutive men complaining of chronic cough were prospectively recruited. All subjects completed the CQLQ prior to any contact with the cough specialist and medical intervention. Prior to embarking on this study, approval was obtained from our institutional review board for human studies. Differences between groups were compared with the unpaired Student t test, the Mann-Whitney U test, {chi}2 analysis, and analysis of variance (ANOVA). The 0.05 level of significance was used throughout.

The CQLQ is a 28-item paper-and-pencil survey that was developed by the authors.2 It has been shown to have dimensionality consistent with a cough-specific quality-of-life (QOL) instrument. It has been shown to have six subscales with minimal overlap of items. The six subscales are as follows: physical complaints; psychosocial issues; functional abilities; emotional well-being; extreme physical complaints; and personal safety fears. It has been shown to be a valid and reliable method by which to assess the impact of chronic cough on QOL and the efficacy of cough therapies in patients with chronic cough. Each item is scored on a 4-point Likert-type scale numbered 1 (strongly disagree), 2 (disagree), 3 (agree), and 4 (strongly agree). The highest possible total score, indicating the most adverse effects of cough on QOL, is 112. The lowest possible total score, indicating no adverse effects of cough, is 28.


   Results
TOP
 Abstract
 Introduction
 Materials and Methods
 Results
Discussion
 Conclusion
 References
 
Characteristics of Control Smoker Group
This group was composed of 31 smokers who were not seeking medical attention. They were observed to be coughing in an employee smoking area and were not complaining of cough. There were 22 women and 9 men in the group with a mean (± SD) age of 41.4 ± 11.3 years.

CQLQ Scores for Women and Men in the Control Smoker Group
Men’s total CQLQ scores were higher than those for women (32.86 ± 7.85 vs 40.44 ± 7.53, respectively; t29 = 2.47; p < 0.02). Men also scored higher than women on the following two subscales: physical complaints (10.18 ± 2.12 vs 14.33 ± 3.96, respectively; t9.9 = 2.97; p < 0.02); and emotional well-being (3.9 ± 1.54 vs 5.33 ± 1.41, respectively; t29 = 2.39; p < 0.03). Subscale scores were similar for men and women on the remaining subscales: psychosocial issues (6.77 ± 3.22 vs 8.11 ± 2.02, respectively; t29 = 1.15; p = 0.259 [not significant]); extreme physical complaints (4.63 ± 1.17 vs 4.55 ± 1.13, respectively; t29 = -0.18; p = 0.862 [not significant]); functional abilities (5.27 ± 0.63 vs 6.11 ± 1.53, respectively; t9.1 = 1.58; p = .147 [not significant]); and personal safety fears (4.5 ± 0.96 vs 4.6 ± 0.86, respectively; t29 = 0.45; p = 0.657 [not significant]).

Scores for the 28 individual items are summarized in Table 1 along with the respective item scores for chronic coughers to facilitate comparisons analyzed below. Women scored significantly higher than men in only one item score, wetting the pants (t29 = -2.485; p = 0.021). Men scored significantly higher than women on the following five items: family cannot tolerate it (t29 = 3.075; p = 0.005); hoarseness (t29 = 2.612; p = 0.014); hurts to breathe (t29 = 3.973; p < 0.0001); exhaustion (t29 = 2.361; p = 0.042); and want to be reassured that I do not have anything serious (t29 = 2.712; p = 0.011).


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  		Table 1.. Individual Item Scores of Women and Men With Chronic Cough and Smokers*

 
Characteristics of Chronic Coughers
The original cohort of chronic coughers was composed of 154 subjects (38 men and 116 women) with a mean (± SD) age of 54.3 ± 14.3 years. They had complained of cough for a mean duration of 76.6 ± 83.6 months. Seventy-five percent of these patients were women. Therefore, women outnumbered the men by 3:1 (p < 0.0001). The present study group enhanced with data from 18 additional men was composed of 172 subjects (56 men and 116 women). The mean ages of the men and women were 51.4 ± 14.9 and 54.7 ± 13.8 years, respectively, and the mean durations of cough of the men and women were 63.4 ± 82.6 and 77.4 ± 82.9, respectively. There was no significant difference between women and men with respect to age (p = 0.154) or duration of cough (p = 0.304).

Comparison of CQLQ Scores for Women and Men in the Chronic Cougher Group
A comparison of total mean (± SE) CQLQ scores for women and men is shown in Figure 1 . Total CQLQ scores for women were significantly higher than for men (67.1 ± 1.3 vs 59.7 ± 1.8, respectively; p = 0.002). A comparison of the six subscale mean (± SE) CQLQ scores for women and men is shown in Figure 2 . Women had significantly higher scores than men on the following subscales: physical complaints (21.6 ± 0.5 vs 19.0 ± 0.7, respectively; p = 0.004); psychosocial issues (14.7 ± 0.3 vs 12.9 ± 0.4, respectively; p = 0.002); and extreme physical complaints (8.9 ± 0.26 vs 6.6 ± 0.26, respectively; p < 0.001). There was no statistical difference between the genders on the remaining subscales: functional abilities (11.2 ± 0.3 vs 10.4 ± 0.5, respectively; p = 0.210); emotional well-being (7.5 ± 0.17 vs 7.9 ± 0.26, respectively; p = 0.201); and personal safety fears (6.2 ± 0.18 vs 6.0 ± 0.25, respectively; p = 0.608).



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  		Figure 1.. Comparison of total CQLQ scores for women and men. The mean total CQLQ score for women was significantly higher than for men (data plotted as mean ± SE). The minimum possible score is 28, and the maximum possible score is 112.

 


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  		Figure 2.. Comparison of CQLQ subscale scores for women and men. While there were no differences in the subscale scores of functional abilities, emotional well-being, and personal safety fears, the mean scores for women were significantly higher than those for men in the remaining subscales of psychosocial issues, physical complaints, and extreme physical complaints. Data are plotted as the mean ± SE.

 
Scores of women and men for the 28 individual items that make up the six subscales of the CQLQ are summarized in Table 1 . Of the 28 individual items, there were significantly higher gender differences in 10. In all, the scores for women were higher than those for men, and they all were distributed in the three subscales where there were significant subscale differences (Fig 2) . A comparison of the 10 item scores for women and men, and the respective subscales in which they reside is shown in Figure 3 . The 10 items in which women scored higher included the following: family cannot tolerate it; embarrassed; upset by response of others; sick to stomach; retching; wetting pants; headache; ache all over; hurts to breathe; and exhaustion. There were no significant differences in the remaining 18 items: prolonged absences from important activities; being completely prevented from engaging in important activities; lost appetite; fear of AIDS/tuberculosis; concern of cancer; dizzy; soiled pants; sweating; hoarseness; broke rib; cannot sleep at night; difficulty speaking on phone; can no longer sing; stopped going to social activities; had to change lifestyle; want to be reassured that I do not have anything serious; self conscious; and concerned that I have something serious.



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  		Figure 3.. Gender differences in CQLQ items in their respective subscales. Of the 28 individual items that compose the six subscales, women scored significantly higher in 10 items and were distributed within the three significant subscales as shown. Data are plotted as the mean ± SE. Women and men scored similarly on the remaining 18 items that are described in the text.

 
Comparison of Gender Differences in CQLQ Scores for Chronic Coughers vs Control Smokers
Utilizing group-by-gender ANOVA, the differences between women and men chronic coughers were compared to the differences between women and men smokers. Significant group-by-gender differences indicated that the differences between women and men chronic coughers were significantly greater than those between women and men smokers in the following scores: total score, F1,199 = 6.807, p = 0.010; three subscale scores (psychosocial, F1,199 = 4.730, p = 0.031; physical complaints, F1,199 = 9.092, p = 0.003, and extreme physical complaints, F1,199 = 4.705, p = 0.031); and 10 individual item scores. The individual items included the following: family cannot tolerate it, F1,199 = 8.030, p = 0.005; headache, F1,199 = 4.080, p = 0.045; wetting pants, F1,199 = 5.989, p = 0.015; sweating, F1,199 = 4.276, p = 0.040; hoarseness, F1,199 = 5.524, p = 0.020; hurts to breathe, F1,199 = 19.214, p < 0.0001; cannot sleep at night, F1,199 = 4.029, p = 0.046; exhaustion, F1,199 = 7.949, p = 0.005; want to be reassured that I do not have anything serious, F1,199 = 8.826, p = 0.003; and upset by response of others, F1,199 = 4.638, p = 0.032.


   Discussion
TOP
 Abstract
 Introduction
 Materials and Methods
 Results
 Discussion
Conclusion
 References
 
Cough can mean different things to different people. It depends on their perspective. To the patient, coughing is an indicator that something is wrong with their body, and it can be the cause of a variety of complications6 that can significantly decrease their HRQOL.2 Because the term HRQOL defines a patient’s perception of the impact of health and disease on multiple domains of his/her life (eg, physical function and psychosocial state), it is of the highest importance to patients. With respect to coughing, cough-specific HRQOL questionnaires have the potential to most accurately reflect the severity of cough from the patient’s standpoint because the patient’s answers integrate the impact of cough frequency as well as intensity. It is for this reason that we decided to compare the relative impacts of chronic coughing on the HRQOL of women and men utilizing data obtained with the CQLQ,2 a valid and reliable, cough-specific HRQOL instrument.

Our study involved an analysis of CQLQ data that included previously prospectively collected, but not previously analyzed or reported results,2 and additional CQLQ data that were prospectively collected to enrich our database to make meaningful gender comparisons. From this analysis, three important findings emerged.

First, our results in the nonenriched, original cohort of coughers have confirmed that more women than men seek medical care because of chronic cough. The 3:1 ratio of women to men in our study falls within the range of ratios of 1.2:17 to 3.6:18 that have been prospectively reported from around the globe9 10 11 12 over the past 20 years.

Second, the HRQOL of women with chronic cough who seek medical attention because of cough is more adversely affected than men. This finding is based on a comparison of the results of the total and subscale CQLQ scores in which women complaining of chronic cough scored significantly higher than men complaining of chronic cough in total (Fig 1) and on three subscales (Fig 2) . The results in our control group of smokers with cough who were not seeking medical attention because of cough supports this conclusion. In this control group, contrary to the results in chronic coughers, the cough-specific HRQOL of men was significantly more adversely affected than women. While men and women smokers scored similarly on four subscales, smoking men scored significantly higher than smoking women in total CQLQ scores and in two subscale scores. To our knowledge, these findings have not been previously reported. Nevertheless, we feel confident that these findings are real because they are based on data obtained with the CQLQ, a valid and reliable HRQOL instrument.2

Third, the HRQOL of women with chronic cough who seek medical attention is adversely affected in different ways than men. This finding is based on a comparison of the scores of the six subscales and individual items of the CQLQ (Fig 2 , 3) . Women scored significantly higher than men in the following categories: (1) physical complaints such as headache, ache all over, hurts to breathe, and exhaustion; (2) psychosocial issues such as family cannot tolerate it, embarrassed, and upset by response of others; and (3) extreme physical complaints such as sick to stomach, retching, and wetting pants. The greatest disparity, and the most significant difference in the scores of the individual items (ie, complaints) between women and men, was found in wetting pants (Fig 3) . To our knowledge, these findings also have not been previously reported. Nevertheless, we feel confident that they are real because they are based on data obtained with a valid and reliable cough-specific HRQOL instrument.2

To further validate that the gender differences in HRQOL in chronic coughers were due to their chronic cough and not to gender differences in general, we compared the CQLQ scores of chronic coughers with our control group of smokers who were not complaining of cough. By performing an ANOVA, we showed that the gender differences in HRQOL of women compared to men with chronic cough either were significantly different or significantly greater than the differences in HRQOL of women and men not complaining of cough. With respect to wetting the pants, our analysis has confirmed what has been known about urinary incontinence for years.13 14 15 16 Women in the general population (and in our cohort of smokers from the general population) are more likely to complain of urinary incontinence than men. And, chronic coughing makes this difference greater (ie, stress incontinence).


   Conclusion
TOP
 Abstract
 Introduction
 Materials and Methods
 Results
 Discussion
 Conclusion
References
 
We conclude that women with chronic cough in our study were probably more inclined to seek medical attention than men with chronic cough because the HRQOL of the women was more adversely affected than men, and because women were more apt to experience physical complaints such as stress urinary incontinence that provoked psychosocial issues such as becoming embarrassed. Because we did not measure cough reflex sensitivity in our study, it is not possible to know whether or not a higher cough reflex sensitivity contributed to these HRQOL effects.


   Footnotes
 
Abbreviations: ANOVA = analysis of variance; CQLQ = cough quality-of-life questionnaire; HRQOL = health-related quality of life; QOL = quality of life

Presented in part and published in abstract form at the annual meeting of the American Thoracic Society, May 20, 2001, in San Francisco, CA.

Received for publication June 24, 2003. Accepted for publication September 24, 2003.


   References
TOP
 Abstract
 Introduction
 Materials and Methods
 Results
 Discussion
 Conclusion
 References
 

  1. French, CL, Irwin, RS, Curley, FJ, et al (1998) Impact of chronic cough on quality of life. Arch Intern Med 158,1657-1661[Abstract/Free Full Text]
  2. French, CT, Irwin, RS, Fletcher, KE, et al Evaluation of a cough-specific quality-of-life questionnaire. Chest 2002;121,1123-1131[Abstract/Free Full Text]
  3. Irwin, RS, Boulet, L-P, Cloutier, MM, et al Managing cough as a defense mechanism and as a symptom: a consensus panel report of the American College of Chest Physicians. Chest 1998;114,133S-181S[ISI][Medline]
  4. Fujimura, M, Sakamoto, S, Kamio, Y, et al Sex differences in the inhaled tartaric acid cough threshold in non-atopic healthy subjects. Thorax 1990;45,633-634[Abstract/Free Full Text]
  5. Kastelik, JA, Thompson, RH, Aziz, I, et al Sex-related differences in cough reflex sensitivity in patients with chronic cough. Am J Respir Crit Care Med 2002;166,961-964[Abstract/Free Full Text]
  6. Irwin, RS, French, CT, Fletcher, KE Quality of life in coughers. Pulm Pharmacol Ther 2002;15,283-286[CrossRef][ISI][Medline]
  7. Irwin, RS, Corrao, WM, Pratter, MR Chronic persistent cough in the adult: the spectrum and frequency of causes and successful outcome of specific therapy. Am Rev Respir Dis 1981;123,413-417[ISI][Medline]
  8. Marchesani, F, Cecarini, L, Pela, R, et al Causes of chronic persistent cough in adult patients: the results of a systematic management protocol. Monaldi Arch Chest Dis 1998;53,510-514[Medline]
  9. Irwin, RS, Curley, FJ, French, CL Chronic cough: the spectrum and frequency of causes, key components of the diagnostic evaluation, and outcome of specific therapy. Am Rev Respir Dis 1990;141,640-647[ISI][Medline]
  10. Pratter, MR, Bartter, T, Akers, S, et al An algorithmic approach to chronic cough. Ann Intern Med 1993;119,977-983[Abstract/Free Full Text]
  11. Carney, IK, Gibson, PG, Murree-Allen, K, et al A systematic evaluation of mechanisms in chronic cough. Am J Respir Crit Care Med 1997;156,211-216[Abstract/Free Full Text]
  12. Palombini, BC, Astilhos, CA, Araujo, E, et al A pathogenic triad in chronic cough: asthma, postnasal drip syndrome, and gastroesophageal reflux disease. Chest 1999;116,279-284[Abstract/Free Full Text]
  13. Busby-Whitehead, JM, Johnson, TM Urinary incontinence. Clin Geriatr Med 1998;14,285-296[ISI][Medline]
  14. Thom, D Variation in estimates of urinary incontinence prevalence in the community: effects of differences in definition, population characteristics, and study type. J Am Geriatr Soc 1998;46,473-480[ISI][Medline]
  15. Hunskaar, S, Arnold, EP, Burgio, K, et al Epidemiology and natural history of urinary incontinence. Int Urogynecol J Pelvic Floor Dysfunct 2000;11,301-319[CrossRef][Medline]
  16. Romanzi, LJ Urinary incontinence in women and men. J Gend Specif Med 2001;4,14-20[Medline]



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