create the summary of the findings " Methods
This cross-sectional retrospective descriptive study was conducted by reviewing injured 
veterans’ medical records participating in the health screening program in Khatam Alanbia 
Hospital, Tehran, in 2013, supervised by Shefa Neuroscience Research Center. Inclusion 
criteria were at least one year elapsed since the injury, level of injury lower than C3, having no 
history of hospitalization and using mechanical ventilation in 3 months prior to attending the 
center. Data were collected in a checklist of demographic information, spirometry results and 
history of pneumonia, cough, dyspnea, the type and level of injury. The type of injury was 
determined based on complete or incomplete injury and the level of injury based on the 
Cervical, thoracic and lumbar spinal cord injury and also based on tetraplegia and paraplegia. 
Unfortunately, Type of injury was not written according to ASIA classification in veterans’ 
medical records and only FEV1 and FVC and the ratio could be extracted from spirometry 
results. 
Data were analyzed in SPSS v20 software and the significance level was considered less than 
0.05 (p<0.05). 
Results And Discussion
Among participants, 368 injured veterans had the inclusion criteria for the study. All subjects were male 
with the mean age of 49.62 ± 6.45 years. The mean time since injury was 27.17 ± 5.03 years; 32 veterans 
(8.7%) suffered from tetraplegia and 336 (91.3%) were paraplegic; 120 veterans (32.6%) had complete 
and 248 had incomplete spinal cord injury (67.4%). 
Among them, 159 veterans had problem for effective coughing; 198 complained of dyspnea and 119 had 
a history of hospitalization for pneumonia during the last year. 
Tables 1, 2 and 3 show the results based on 3 models. Table 1 presents data based on complete and 
incomplete spinal cord injury. In this model, there was a significant statistical difference between the two 
groups in terms of FEV1 and FVC and FEV/FVC and they were higher in incomplete spinal cord injury. 
Table 1. Characteristics of veterans based on Injury type.
Characteristics
Injury
Complete p value
(N= 120)
Incomplete
(N=248)
Tetraplegia, N % 16 (13.3) 16 (6.45) 0.05>
Paraplegia, N % 104 (86.6) 232 (93.54)
Level of injury, N %
Cervical 16 (13.3) 16 (6.45)
Thoracic 54 (45) 186 (75) 0.001>
Lumbar 50 (41.6) 46 (18.54)
Age, mean±SD, y 49.40±6.98 49.73±6.2
Post SCI period, mean±SD, y 27.36±4.96 27.09±5.07
FEV1, mean±SD, L 2.76±0.75 3.08±0.48 0.001>
FVC, mean±SD, L 3.09±0.79 3.42±0.50 0.001>
FEV1/FVC, mean±SD, % 88.66±5.04 90.18±3.14 0.01>
Ineffective Cough, N % 55 (45.8) 104 (41.93)
Dyspnea, N % 62 (51.6) 136 (54.83)
Hx of Pneumonia, N % 35 (29.1) 84 (33.87)
Smoker, N % 8 (6.6) 65 (26.20) 0.001>
BMI, N %
<25 43 (35.83) 76 (30.64)
25‐30 55 (45.83) 129 (52.01)
≥30 22 (18.33) 43 (17.33)
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Table 2. Characteristics of veterans based on type of plegia.
Characteristics Tetraplegia p value
(N=32)
Paraplegia
(N=336)
Age, mean±SD, y 49.40±7.03 49.64±6.41
Post SCI period, mean±SD, y 27.37±4.85 27.15±5.05
FEV1, mean±SD, L 2.28±0.80 3.04±0.54 0.01>
FVC, mean±SD, L 2.57±0.83 3.38±0.56 0.001>
FEV1/FVC, mean±SD, % 88.13±5.56 89.82±3.71
Ineffective Cough, N % 16 (50) 143 (42.55)
Dyspnea, N % 16 (50) 182 (54.16)
Hx of Pneumonia, N % 14 (43.75) 105 (31.25)
Smoker, N % 0 (0) 73 (21.72)
BMI, N %
<25 12 (37.5) 107 (31.84)
25‐30 13 (40.62) 171 (50.89)
≥30 7 (21.87) 58 (17.26)
Table 3. Characteristics of veterans based on level of injury.
Characteristics
Level of injury
Cervical p value
(N=32)
Thoracic
(N=240)
Lumbar
(N=96)
Age, mean±SD, y 49.40±7.03 49.64±6.41 48.92±7.33
Post SCI period, mean±SD, y 27.37±4.85 27.15±5.05 26.90±5.68
FEV1, mean±SD, L 2.28±0.80 3.04±0.54 3.32±0.42 0.001>
FVC, mean±SD, L 2.57±0.83 3.38±0.56 3.65±0.43 0.001>
FEV1/FVC, mean±SD, % 88.13±5.56 89.82±3.71 90.86±3.34 0.001>
Cough, N % 16 (50) 101 (42.08) 42 (43.75)
Dyspnea, N % 16 (50) 131 (54.16) 51 (53.12)
Pneumonia, N % 14 (43.75) 74 (54.58) 31 (32.29)
Smoker, N % 0 (0) 54 (22.5) 19 (19.79) 0.01>
BMI, N %
<25 12 (37.5) 77 (32.08) 30 (31.25)
25‐30 13 (40.62) 120 (50) 51 (53.12)
≥30 7 (21.87) 43 (17.91) 15 (15.62)
Based on the data shown in Tables 2 and 3, FEV1 and FVC were significantly higher in paraplegic, 
thoracic and lumbar group. Reviewing the effect of age and the time period after injury, BMI and smoking 
on FEV1 and FVC and FEV/FVC, no significant relationship was observed. In this study, the results of 
spirometry indices are the same as cohort studies in which people are not able to perform spirometry 
according to ATS standards. In these people, the rate of FEV1 decline is observed more, and mortality is 
also increased (Stolzmann, et al., 2008). Although a history of respiratory symptoms such as ineffective 
cough, dyspnea and respiratory infection in people without spinal cord injury can affect the results of 
spirometry (Petsonk and Wang, 2010), this condition was not significantly seen in people with spinal cord 
injury and the reason for this difference is not well understood (Galeiras, et al., 2013). In this study, 
FEV1/FVC was reduced in complete spinal cord injury and high level injury. In Los Angeles cohort study 
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(Jain, et al., 2006), there was a higher proportion of tetraplegia than paraplegia which is the opposite of 
our result. Several studies on non-spinal cord injury showed that the ratio of FEV1/FVC increases with 
increasing BMI (Galeiras, et al., 2013). In our study, there was no significant relationship between BMI and 
spirometry indices, while a study on patients with spinal cord injury showed that FEV1/FVC is decreased 
by increasing weight and BMI (Stepp, et al., 2008). 
In spinal cord injury, pulmonary volumes and air flow rate are decreased due to respiratory muscle 
weakness (Tollefsen and Fondenes, 2012). Changes in spirometry results can be affected by the level of 
injury, lying or sitting position during the test (Terson, et al., 2014). Several studies show pulmonary 
volumes especially FVC and FEV1 increase in lower level spinal cord injury; while higher level of injury 
reduces the total lung volume (Stolzmann, et al., 2008; Kelley, et al., 2013). With increased residual 
volume, functional residual capacity volume is decreased. Decreased expiratory reserve volume can have 
a direct relationship with the main and abdominal respiratory muscle weakness (Jain, et al., 2006). A 
recent study showed that pulmonary volumes and oxygenation are improved in a semi-sitting position in 
the acute respiratory distress syndrome. However, the studies on individuals with spinal cord injury 
suggest that tetraplegic people show better pulmonary function in the supine position (Terson, et al., 
2014). With increasing age and decreasing weight, FVC and FEV1 increases in normal people. However, 
these effects may be indirect. Respiratory system dysfunction depends on the extent and the level of 
injury and nerve damage, so that patients with cervical spinal cord injury and upper thoracic injury are at a 
greater risk of respiratory disorders (Petsonk and Wang, 2010; Galeiras, et al., 2013). Several studies also 
indicate that the dependence on mechanical ventilation is higher in patients with cervical spinal cord injury 
higher than C4 (Zimmer, et al., 2007; Tollefsen and Fondenes, 2012). In our study, an inverse relationship 
was observed between the time period after injury and FVC and FEV1, and FVC and FEV1 was better as 
time passed. However, most studies have reported a decrease in FVC and FEV1 (Jain, et al., 2006; 
Kelley, et al., 2013). This difference could be due to the number of tetraplegic people and injury with 
complete neurological damage in studies. In this study, this situation can be indirectly justified by the 
better nursing and care of injured veterans. Many factors affect spirometry results of people with spinal 
cord injury, however, this study showed that the reduction in FEV1 and FVC in veterans with spinal cord 
injury is directly associated with the type (complete and incomplete) and the level of injury. 
In general, according to results, it seems that veterans’ respiratory status in the screening was appropriate 
indicating proper regular visits of veterans at home. It is suggested that future studies be conducted 
simultaneously with health screening programs and the international standard forms be used in patients’ 
medical records. "