Breathlessness and exercise in spinal cord injury.

After spinal cord injury (SCI), breathlessness during daily activities is common. In 308 individuals with SCI, the authors measured pulmonary function and administered a survey regarding health status, participation in wheelchair athletics, and breathlessness during different activities. The following questions were included: A. Are you troubled by shortness of breath when hurrying on the level or going up a slight hill?; B. Do you have to go slower than people of your own age on the level because of breathlessness?; C. Do you ever have to stop for breath when going at your own pace on the level?; and D. Do you ever have to stop for breath after going about 100 yards on the level? The analysis was restricted to 183 subjects with neurologically motor complete or incomplete SCI who, to get around, used hand-propelled wheelchairs more than 50% of the time. Of these, 56 (31%) reported breathlessness during some types of activities. Subjects with neurologically motor complete cervical or high thoracic SCI (T-6 and above) were more likely to report breathlessness than others (39% compared with 25%, p = .039). Among wheelchair athletes, the prevalence of breathlessness was 8/49 (16%) versus 48/134 (36%) for non-athletes (p = .011). Adjusting for smoking, neurological level, and history of obstructive lung disease, non-athletes were 2.3 times more likely to report breathlessness than athletes were (p = .049 to .075, depending on regression model). This relationship persisted when adjusted for percent predicted forced expiratory volume (FEV1) and maximal expiratory and inspiratory pressures. Therefore in SCI, wheelchair athletes are less likely to report breathlessness than non-athletes, but the mechanism does not appear to be improvement in respiratory muscle performance or pulmonary function.

Breathlessness in spinal cord injury depends on injury level.

Little is known about the prevalence and predictors of breathlessness in individuals with neurologically complete chronic spinal cord injury (SCI). Between December 1992 and September 1993, we mailed a respiratory questionnaire to 1,147 community-based individuals with chronic SCI. The questionnaire included four questions about the presence of breathlessness during activities related to moving about. Of the 485 who replied (42 percent response rate), analysis was limited to adult males with neurologically complete motor injuries who reported using a hand-propelled wheelchair more than 50 percent of the time to get around. Of 130 subjects (33 tetraplegics, 53 high thoracic SCI, 44 lower injury levels), the patients with tetraplegia reported breathlessness more frequently (range for the four questions, 21-33%) than those with high thoracic (range, 9-15%) or lower injury levels (range, 2-11%). For each of the four questions there was a significant trend (p < 0.05) for subjects with higher levels of injury to report the greatest prevalence of breathlessness (tetraplegia > high thoracic > lower). The frequency of breathlessness was greatest in those with neurologically complete cervical injuries, an effect that was independent of obesity, smoking, age, and years since SCI. The mechanisms of breathlessness in SCI are unclear but elucidation might lead to strategies for providing relief.