In the present study, spontaneously reported descriptors of dyspnea and associated symptoms were elicited in Chinese patients to make a symptom checklist. This was used to collect frequency evaluations in new groups of Chinese patients with different cardiopulmonary diseases and medically unexplained dyspnea, and in healthy subjects. Test-retest reliability in these 328 subjects was satisfactory for most of the descriptors. A principal component analysis on 61 Chinese descriptors yielded eight factors. The descriptors of dyspnea were separately allocated to the following three factors: dyspnea-effort of breathing; dyspnea-affective aspect; and wheezing. The other five factors grouped the associated symptoms of dyspnea, namely, anxiety, tingling, palpitation, coughing and sputum, and dying experience. To what extent are the Chinese descriptors different from those in Western cultures?
The Descriptors of Breathlessness in Chinese
Dyspnea-Effort of Breathing: Simon et al initially studied the language of breathlessness and solicited 19 phrases describing respiratory discomfort from patients with cardiopulmonary diseases. These investigators administered a list of these phrases to 53 patients with breathlessness due to pregnancy and a variety of cardiopulmonary disorders, and found that certain descriptors were associated with breathlessness in different disease condi-tions. The association of specific descriptors with different pathophysiologic conditions was further replicated in a large sample of patients with a diagnosis of COPD, asthma, interstitial lung disease, congestive heart failure, cystic fibrosis, deconditioning, and neuromuscular disease, and in healthy subjects.
It is difficult to compare our results with the results of those studies for a number of reasons. First, compared to the present study, these investigators collected a much smaller set of descriptors, prompted by a more specific question (“describe the sensations associated with uncomfortable awareness of breathing”). Second, the studies mentioned collected dichotomous judgments (ie, the descriptor was or was not applicable), whereas we used retrospective frequency-of-occurrence judgments over the past month. Third, they used cluster analysis to group the descriptors, whereas we used principal-component analysis. Fourth, either healthy individuals or patient groups were used as subjects, whereas in our study, grouping was done in a mixed group of patients and healthy subjects.
Despite all of these differences, the terms used in Chinese and Western subjects to describe breathing discomfort overlapped considerably with factor 1, which was defined as dyspnea-effort of breathing in the present study. As shown in Table 5, in 11 of 15 English descriptors, identical phrases were found in factor 1. It is likely that common physiologic processes, related to respiratory effort, chemorecep-tor stimulation, mechanical stimuli arising in the lung and chest wall receptors, and the processing of respiratory-related afferent information, as suggested by Manning and Mahler, contribute to the perception of these sensations in similar ways in both cultures. It might be possible that the techniques used in the studies of Simon et al and Mahler et al have resulted in more fine-grained clusters along the dimensions of “depth and frequency of breathing,” “perceived need or urge to breathe,” and “difficulty breathing and phase of respiration.” Different diseases should be treated in time without any hesitations. To read for example about arrhythmia you should check out the web site .
Dyspnea-Affective Aspect: However, not all phrases of dyspnea were allocated to the factor of dyspnea-effort of breathing in the present principal-component analysis. The descriptors of chest tightness, compressed chest, tight throat or lump in the throat, blocked chi in the chest, and blocked chi in the throat were grouped into another factor (factor 6), which was defined as dyspnea-affective aspect. It appeared that some descriptors unique for Chinese emerged in this factor, for example, blocked chi in the chest or in the throat. According to the concept of traditional Chinese medicine, chi is the living energy circulating along specific channels in human body. If chi is blocked in the pathway, disorders of body function will emerge. In this factor, the other concomitant descriptors included chest tightness and tight throat or lump in the throat. The former could be found in the 15 descriptors of breathlessness given by Simon et al, and the latter was often used by patients with anxiety and somatoform disorders. The fact that the descriptors of dyspnea were grouped separately into two distinct factors suggests that dyspnea, like pain, is a multidimensional experience encompassing not only effort of breathing but also an affective aspect.- This latter component appears to be more sensitive to cultural and emotional meanings.
Wheezing: Wheezing, as a classical medical term, means breathing hard with whistling and indicates the presence of the airway obstruction, especially in patients with asthma.’’ Reported wheezing in the patient’s history is considered to be one of the important criteria for the diagnosis of asthma. In the factor analysis of the present study, the phrases gasping, breathing more, exhaling more, whistling while breathing, whistling in the throat, and whistling in exhalation were grouped under factor 2, which was defined as wheezing. In fact, the meaning of gasping and whistling used in Chinese is not different from that used in Western cultures. It is possible that the perception of wheezing, similar to the other descriptors in dyspnea-effort of breathing, is mainly influenced by the physiologic change (eg, the airflow obstruction), rather than by cultural factors. Therefore, wordings indicating the same meaning could be identified not only in Western and Chinese cultures but also by people in Thailand, as evidenced by the study of Phankingthongkum et al on Thai terminology of wheezing. To what extent are the factors differentially related to diagnostic categories?
The Relation of the Dyspnea Language and the Clinical Diagnosis
The ability of the symptom descriptions to differentiate diseases is considered to be an evidence of construct validity. For this purpose, a variance analysis with Duncan grouping was used to compare the scores of the symptom factors in different categories of patients and in healthy subjects. As shown in Table 4, the factor of dyspnea-effort of breathing was shared by different categories of patient, with the highest scores attributed to patients with medically unexplained dyspnea. This component of effortful breathing may imply both a dynamic aspect, which may be obvious in patients having to overcome pulmonary malfunction such as asthmatic patients, and a static component related to hyperinflation, which may be particularly prominent in patients with medically unexplained dyspnea.
The factors of dyspnea-affective aspect and wheezing appeared to be primarily linked to the diagnosis of medically unexplained dyspnea and asthma. However, wheezing characterized asthma and was not present in patients with medically unexplained dyspnea. In that respect, the symptom factors could make a meaningful contribution to the differential diagnosis. For instance, if a patient reports wheezing, a diagnosis of medically unexplained dyspnea is very unlikely. On the other hand, anxiety, tingling, and dying experience seemed to be unique for patients with medically unexplained dyspnea. This would mean that in a patient complaining of, for instance, compressed chest or blocked chi, dyspnea would be likely to be nonorganic in origin if, in addition, the patient is clearly anxious and is presenting symptoms of tingling in the body. For patients with dyspnea, the occurrence of coughing, sputum, and hemoptysis would direct the physician’s attention to the organic lung diseases, whereas the presence of effortful breathing combined with palpitation (factor 5) may point to a cardiac origin of dyspnea.
In the present study, the descriptors of breathlessness were investigated mainly in Mandarin speakers living in northern China (Fig 1). One may question the generalizability of the results to other dialects used in southern China, for instance, Cantonese and Shanghaihua. Indeed, it is quite difficult for the speakers of different dialects to understand each other. It all depends on the tone of voice that each dialect uses. At times, in one sentence, each word has a different tone, so that the same word might mean one thing in one dialect and another thing in another dialect. However, the writing language is the same. Although they cannot understand each other’s speech, they can well understand each other when they put words on paper, for example, in a written questionnaire. Even so, further validation of the present results in Canton and Shanghai is needed before clinical application in those areas
In summary, the following three factors of breathlessness were found in Chinese subjects: dyspnea-effort of breathing; dyspnea-affective aspect; and wheezing. The descriptors of dyspnea-effort of breathing and wheezing appear to be similar to those in Western studies, whereas the descriptors of dyspnea-affective aspect seem to bear cultural specificity. Although the descriptors of dyspnea-effort of breathing are shared by patients with a variety of diseases, the descriptors of dyspnea-affective aspect and wheezing are unique to a particular clinical condition.
Table 5—Comparison Between Descriptors Proposed by Simon et al and Those in the Present Study
|Descriptors Proposed by Simon et al||Descriptors in the Present Study|
|My breathing requires effort||Breathing with difficulty or with effort (F1)|
|My breathing requires work|
|I feel out of breath||Shortness of breath (F1)|
|I cannot get enough air in||Attempt to breathe in with much|
Inability to breathe in deeply enough (F1)
A need to take a deep inspiration
|I feel that I am smothering||Being suffocated (F1)|
|I feel that I am suffocating|
|My breath does not go out all the way||Difficult to breathe out (F1)|
My breath does not go out all the way (F1)
I cannot breathe out (F1)
|My chest feels tight||Chest tightness (F6)|
|My chest is constricted||Oppressive chest (F1) Compressed chest (F6)|
|My breath does not go in all the way||
My breath does not go in all the
|My breathing is rapid||I cannot breathe in (F1) Breathing fast (F1) Rapid respiration (F1)|
|I feel that I am breathing more||Breathing more (F2)|
|I feel a hunger for air||Hunger for more air (F1)|
|My breathing is shallow My breathing is heavy|
My breathing needs conscious help
I cannot breathe enough (F1) Desperate for breath to come (F1)