Relationship of respiratory symptoms with smoking status and pulmonary function in chronic spinal cord injury.
OBJECTIVE
The relationship of respiratory symptoms to pulmonary function parameters and smoking status was assessed in subjects with chronic (>1 year) spinal cord injury (SCI).


METHODS
As part of their annual physical examination, subjects were queried regarding respiratory symptoms and underwent pulmonary function studies. The 180 patients who successfully completed pulmonary function testing were evaluated, including 79 subjects with tetraplegia (56 nonsmokers and 23 smokers) and 101 subjects with paraplegia (78 nonsmokers and 23 smokers).


RESULTS
Logistic-regression analysis revealed the following independent predictors of breathlessness: level of injury (tetraplegia, paraplegia, odds ratio = 3.5, P < 0.0015), cough combined with phlegm and/or wheeze (CPWZ, odds ratio = 3.1, P < 0.015), total lung capacity percentage predicted (TLC <60%, odds ratio = 3.9, P < 0.02), and expiratory reserve volume (ERV < 0.6 L, odds ratio = 2.5, P < 0.05). Independent predictors of CPWZ were current smoking (odds ratio = 3.3, P < 0.004), breathlessness (odds ratio = 2.9, P < 0.03), and forced expiratory volume in 1 second (FEV1 <60%, odds ratio = 3.2, P < 0.01).


CONCLUSIONS
Altered respiratory mechanics associated with tetraplegia contribute to breathlessness, restrictive ventilatory impairment (low TLC%), and reduced expiratory muscle strength (low ERV). These factors apparently overshadow adverse effects caused by smoking. Conversely, smoking and reduction of airflow (low FEV1%) were predictive of CPWZ, symptoms commonly associated with cigarette use.
Spungen
Ann M
AM
Spinal Cord Damage Research Center, Veterans Affairs Medical Center, Bronx, NY, 10468, USA.
Grimm
David R
DR
Schilero
Gregory
G
Lenner
Roberta
R
Oei
Erwin
E
Bauman
William A
WA
Almenoff
Peter L
PL
Lesser
Marvin
M
D000328:Adult; D002908:Chronic Disease; D005260:Female; D006801:Humans; D008176:Lung Volume Measurements; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012044:Regression Analysis; D012120:Respiration Disorders / Q000150:complications* / Q000503:physiopathology*; D012129:Respiratory Function Tests; D012907:Smoking / Q000503:physiopathology*; D013119:Spinal Cord Injuries / Q000150:complications* / Q000503:physiopathology*; D013147:Spirometry; D015599:Trauma Severity Indices