Correction: Plasma vitamin D, past chest illness, and risk of future chest illness in chronic spinal cord injury (SCI): a longitudinal observational study.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Plasma vitamin D, past chest illness, and risk of future chest illness in chronic spinal cord injury (SCI): a longitudinal observational study.

STUDY DESIGN: Observational study. OBJECTIVE: Assess associations between vitamin D levels and other risk factors on future chest illness in a chronic spinal cord injury (SCI) cohort. SETTING: Veterans Affairs Boston and the Boston, MA community. METHODS: Between August 2009 and August 2017, 253 participants with chronic SCI were followed over a median of 3.2 years (up to 7.4 years) with two to four visits a median of 1.7 years apart. At each visit, plasma 25-hydroxyvitamin D level was obtained, spirometry performed, and a respiratory questionnaire assessing chest illnesses since last visit was completed. Repeated measures negative binomial regression was used to assess chest illness risk longitudinally. RESULTS: At entry, 25% had deficient vitamin D levels (<20 nanograms/milliliter (ng/ml)), 52% were insufficient (20 to <30 ng/ml), and 23% were sufficient (≥30 ng/ml). Over 545 study visits, chest illnesses (n = 106) were reported by 60 participants. In multivariable models (including previous chest illness history), deficient vitamin D levels (compared with those with sufficient levels) were associated with future chest illness though with wide confidence limits (relative risk (RR) = 1.36, 95% confidence intervals (CI) = 0.74, 2.47). The strongest association with chest illness during the follow-up period was in persons who reported pneumonia/bronchitis after injury and a chest illness in the three years before study entry (RR = 7.62; 95% CI = 3.70, 15.71). CONCLUSION: Assessed prospectively in chronic SCI, there was a suggestive association between deficient vitamin D levels and future chest illness. Past chest illness history was also strongly associated with future chest illness.

Vitamin D, diet, and lifestyle in a chronic SCI population.

STUDY DESIGN: Cross-sectional study. OBJECTIVES: Determine dietary, lifestyle, and clinical factors associated with plasma 25-hydroxyvitamin D [25(OH)D] levels in persons with chronic spinal cord injury (SCI). SETTING: Veterans Affairs Medical Center in Boston, MA. METHODS: 174 participants completed food frequency and health questionnaires, provided a blood sample, and underwent dual x-ray absorptiometry (DXA) to assess %total body fat. Linear regression models were used to assess cross-sectional associations of personal, lifestyle, and nutritional factors with plasma 25(OH)D. RESULTS: Independent factors positively associated with higher plasma 25(OH)D included vitamin D intake, age, hours of planned exercise, female sex, white race, wine consumption, and if a never or former smoker. The most important predictor of 25(OH)D was supplement intake. The majority of subjects (98.9% for vitamin D and 74.1% for calcium) did not meet the recommended daily allowance for adults from their diet alone. Level and completeness of SCI, injury duration, mobility, %total body fat, time outside, and comorbid diseases were not associated with plasma 25(OH)D. CONCLUSIONS: Plasma 25(OH)D level in chronic SCI is not associated with clinical factors specific to SCI such as injury level and completeness, injury duration, and mobility mode, but related to supplement intake and other lifestyle factors.

Associations between vitamin D and pulmonary function in chronic spinal cord injury.

CONTEXT/OBJECTIVE: Individuals with chronic spinal cord injury (SCI) have an increased risk of morbidity and mortality attributable to respiratory diseases. Previous studies in non-SCI populations suggest that vitamin D may be a determinant of respiratory health. Therefore, we sought to assess if lower vitamin D levels were associated with decreased pulmonary function in persons with chronic SCI. DESIGN: Cross-sectional study. SETTING: Veterans Affairs Medical Center. PARTICIPANTS: 312 participants (260 men and 52 women) with chronic SCI recruited from VA Boston and the community participating in an epidemiologic study to assess factors influencing respiratory health. METHODS: Participants provided a blood sample, completed a respiratory health questionnaire, and underwent spirometry. Linear regression methods were used to assess cross-sectional associations between plasma 25-hydroxyviatmin D and spirometric measures of pulmonary function. OUTCOME MEASURES: Forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and FEV1/FVC. RESULTS: Adjusted and unadjusted for a number of confounders, there was no significant association between plasma vitamin D levels and FEV1, FVC, or FEV1/FVC. For example, in fully adjusted models, each 10 ng/ml increase in vitamin D was associated with a 4.4 ml (95%CI -64.4, 73.2, P = 0.90) ml change in FEV1. Conclusion: There was no significant cross-sectional association between plasma vitamin D and FEV1, FVC, or FEV1/FVC in this cohort of individuals with chronic SCI.

Plasma Leptin and Reduced FEV1 and FVC in Chronic Spinal Cord Injury.

BACKGROUND: Adipose tissue produces leptin, which is pro-inflammatory, and adiponectin, which has anti-inflammatory properties. Participants with chronic spinal cord injury (SCI) have increased body fat and are at increased risk for respiratory illness. OBJECTIVE: To assess the associations between leptin and adiponectin with pulmonary function in a chronic SCI cohort. DESIGN: Cross-sectional study. SETTING: Veterans Affairs Medical Center. PARTICIPANTS: A total of 285 participants (237 men and 48 women) with chronic SCI with mean (standard deviation) injury duration 17.8 (13.2) years from the VA Boston and the community participating in an epidemiologic study assessing factors associated with respiratory health. METHODS: Participants (24.6% cervical American Spinal Injury Association Impairment Scale (AIS) level A, B, and C; 33.6% other AIS A, B, and C; 41.8% AIS D) provided a blood sample, completed a respiratory health questionnaire, and underwent spirometry. Linear regression methods were used to assess cross-sectional associations between plasma leptin and adiponectin with spirometric measures of pulmonary function adjusted for age, race, gender, and height. Level and severity of SCI, mobility mode, body mass index, smoking, chronic obstructive pulmonary disease, asthma, chest injury history, laboratory batch, and other potential confounders were also considered. MAIN OUTCOME MEASUREMENTS: forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and FEV1/FVC. RESULTS: There was a statistically significant inverse relationship between plasma leptin assessed in quartiles or as a continuous covariate with FEV1 and FVC. In fully adjusted models, each interquartile range (16,214 pg/mL) increase in leptin was associated with a significant decrease in FEV1 (-93.1 mL; 95% confidence interval = -166.2, -20.0) and decrease in FVC (-130.7 mL; 95% confidence interval = -219.4, -42.0). There were no significant associations between leptin and FEV1/FVC or between plasma adiponectin with FEV1, FVC, or FEV1/FVC. CONCLUSION: Plasma leptin in individuals with chronic SCI is inversely associated with FEV1 and FVC, independently of SCI level and severity and other covariates. This finding suggests that plasma leptin may contribute to reduced pulmonary function in chronic SCI. LEVEL OF EVIDENCE: II.

Associations between vitamin D, adiposity, and respiratory symptoms in chronic spinal cord injury.

Context/Objective Persons with chronic spinal cord injury (SCI) have an increased risk of respiratory-related morbidity and mortality and chronic respiratory symptoms are clinical markers of future respiratory disease. Therefore, we sought to assess potentially modifiable factors associated with respiratory symptoms, with a focus on circulating vitamin D and measures of body fat. Design Cross-sectional study. Setting Veterans Affairs Medical Center. Participants Three hundred forty-three participants (282 men and 61 women) with chronic SCI participating in an epidemiologic study to assess factors influencing respiratory health recruited from VA Boston and the community. Methods Participants provided a blood sample, completed a respiratory health questionnaire, and underwent dual x-ray absorptiometry (DXA) to assess % body fat. Logistic regression was used to assess cross-sectional associations between respiratory symptoms and plasma vitamin D and measures of body fat with adjustment for a number of potential confounders. Outcome Measures Chronic cough, chronic phlegm, any wheeze, persistent wheeze. Results After adjustment for a number of confounders (including smoking), participants with greater %-android, gynoid, trunk, or total body fat had increased odds ratios for any wheeze and suggestive associations with persistent wheeze, but not with chronic cough or phlegm. Vitamin D levels were not associated with any of the respiratory symptoms. Conclusion Increased body fat, but not vitamin D, was associated with wheeze in chronic SCI independent of a number of covariates.

FEV1 and FVC and systemic inflammation in a spinal cord injury cohort.

BACKGROUND: Systemic inflammation has been associated with reduced pulmonary function in individuals with and without chronic medical conditions. Individuals with chronic spinal cord injury (SCI) have clinical characteristics that promote systemic inflammation and also have reduced pulmonary function. We sought to assess the associations between biomarkers of systemic inflammation with pulmonary function in a chronic SCI cohort, adjusting for other potential confounding factors. METHODS: Participants (n = 311) provided a blood sample, completed a respiratory health questionnaire, and underwent spirometry. Linear regression methods were used to assess cross-sectional associations between plasma C-reactive protein (CRP) and interleukin-6 (IL-6) with forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and FEV1/FVC. RESULTS: There were statistically significant inverse relationships between plasma CRP and IL-6 assessed in quartiles or continuously with FEV1 and FVC. In fully adjusted models, each interquartile range (5.91 mg/L) increase in CRP was associated with a significant decrease in FEV1 (-55.85 ml; 95% CI: -89.21, -22.49) and decrease in FVC (-65.50 ml; 95% CI: -106.61, -24.60). There were similar significant findings for IL-6. There were no statistically significant associations observed with FEV1/FVC. CONCLUSION: Plasma CRP and IL-6 in individuals with chronic SCI are inversely associated with FEV1 and FVC, independent of SCI level and severity of injury, BMI, and other covariates. This finding suggests that systemic inflammation associated with chronic SCI may contribute to reduced pulmonary function.

Potential neurobiological benefits of exercise in chronic pain and posttraumatic stress disorder: Pilot study.

This pilot study assessed the effects of cardiopulmonary exercise testing and cardiorespiratory fitness on plasma neuropeptide Y (NPY), allopregnanolone and pregnanolone (ALLO), cortisol, and dehydroepiandrosterone (DHEA), and their association with pain sensitivity. Medication-free trauma-exposed participants were either healthy (n = 7) or experiencing comorbid chronic pain/posttraumatic stress disorder (PTSD) (n = 5). Peak oxygen consumption (VO2) during exercise testing was used to characterize cardiorespiratory fitness. Peak VO2 correlated with baseline and peak NPY levels (r = 0.66, p < 0.05 and r = 0.69, p < 0.05, respectively), as well as exercise-induced changes in ALLO (r = 0.89, p < 0.001) and peak ALLO levels (r = 0.71, p < 0.01). NPY levels at the peak of exercise correlated with pain threshold 30 min after exercise (r = 0.65, p < 0.05), while exercise-induced increases in ALLO correlated with pain tolerance 30 min after exercise (r = 0.64, p < 0.05). In contrast, exercise-induced changes in cortisol and DHEA levels were inversely correlated with pain tolerance after exercise (r = -0.69, p < 0.05 and r = -0.58, p < 0.05, respectively). These data suggest that cardiorespiratory fitness is associated with higher plasma NPY levels and increased ALLO responses to exercise, which in turn relate to pain sensitivity. Future work will examine whether progressive exercise training increases cardiorespiratory fitness in association with increases in NPY and ALLO and reductions in pain sensitivity in chronic pain patients with PTSD.

Cross-sectional associations of pulmonary function with systemic inflammation and oxidative stress in individuals with chronic spinal cord injury.

CONTEXT/OBJECTIVE: Systemic inflammation, and to a lesser extent oxidative stress, have been associated with reduced pulmonary function. Our objective was to evaluate the associations between biomarkers of inflammation (C-reactive protein (CRP), interleukin-6 (IL-6)) and novel makers of global oxidative stress (fluorescent oxidation products (FLOx)) with spirometric and lung volume measures in individuals with chronic spinal cord injury (SCI). DESIGN: Cross-sectional study. SETTING: Veterans Affairs Medical Center. PARTICIPANTS: One-hundred thirty-seven men with chronic SCI participating in an epidemiologic study. METHODS: Participants provided a blood sample, completed health questionnaires, and underwent pulmonary function testing, including helium dilution measurement of functional residual capacity (FRC). General linear models were used to model associations between increasing quartiles of inflammation or oxidative stress with each outcome measure, after adjustment for a number of potential confounders. OUTCOME MEASURES: Percent-predicted forced vital capacity in one second (FEV1), percent-predicted forced vital capacity (FVC), FEV1/FVC, percent-predicted residual volume (RV), percent-predicted FRC, and percent-predicted total lung capacity (TLC). RESULTS: After adjustment for a number of confounders, participants with higher levels of CRP and IL-6 had lower percent-predicted FEV1 and FVC measurements. There were no clear patterns of association with any of the oxidative stress biomarkers or other outcome measures. CONCLUSION: Increased systemic inflammation was associated with reductions in FEV1 and FVC independent of a number of covariates. Although the mechanism is uncertain, these results suggest that reductions in pulmonary function in SCI are associated with systemic inflammation.

Urban Mosquito Fauna in Mérida City, México: Immatures Collected from Containers and Storm-water Drains/Catch Basins.

We examined the species composition and temporal occurrence of immature mosquitoes in containers and storm-water drains/catch basins from November 2011 to June 2013 in Mérida City, México. A wide range of urban settings were examined, including residential premises, vacant lots, parking lots, and streets or sidewalks with storm-water drains/catch basins. In total, 111,776 specimens of 15 species were recorded. The most commonly collected species were Aedes (Stegomyia) aegypti (L.) (n = 60,961) and Culex quinquefasciatus Say (45,702), which together accounted for 95.4% of the immatures collected. These species were commonly encountered during both rainy and dry seasons, whereas most other mosquito species were collected primarily during the rainy season. Other species collected were Aedes (Howardina) cozumelensis Diaz Najera, Aedes (Ochlerotatus) taeniorhynchus (Wiedemann), Aedes (Ochlerotatus) trivittatus (Coquillett), Culex coronator Dyar and Knab, Culex interrogator Dyar and Knab, Culex lactator Dyar and Knab, Culex nigripalpus Theobald, Culex salinarius Coquillett, Culex tarsalis Coquillett, Culex thriambus Dyar, Haemagogus equinus Theobald, Limatus durhamii Theobald, and Toxorhynchites rutilus (Coquillett). The greatest number of species was recorded from vacant lots (n = 11), followed by storm-water drains/catch basins (nine) and residential premises (six). Our study demonstrated that the heterogeneous urban environment in Mérida City supports a wide range of mosquito species, many of which are nuisance biters of humans and/or capable of serving as vectors of pathogens affecting humans or domestic animals. We also briefly reviewed the medical importance of the encountered mosquito species.

Associations with chest illness and mortality in chronic spinal cord injury.

OBJECTIVE: Identify factors associated with chest illness and describe the relationship between chest illness and mortality in chronic spinal cord injury (SCI). DESIGN: Cross-sectional survey assessing chest illness and a prospective assessment of mortality. METHODS: Between 1994 and 2005, 430 persons with chronic SCI (mean ± SD), 52.0 ± 14.9 years old, and ≥4 years post SCI (20.5 ± 12.5 years) underwent spirometry, completed a health questionnaire, and reported any chest illness resulting in time off work, indoors, or in bed in the preceding 3 years. Deaths through 2007 were identified. Outcome measures Logistic regression assessing relationships with chest illness at baseline and Cox regression assessing the relationship between chest illness and mortality. RESULTS: Chest illness was reported by 139 persons (32.3%). Personal characteristics associated with chest illness were current smoking (odds ratio =2.15; 95% confidence interval =1.25-3.70 per each pack per day increase), chronic obstructive pulmonary disease (COPD) (3.52; 1.79-6.92), and heart disease (2.18; 1.14-4.16). Adjusting for age, subjects reporting previous chest illness had a non-significantly increased hazard ratio (HR) for mortality (1.30; 0.88-1.91). In a multivariable model, independent predictors of mortality were greater age, SCI level and completeness of injury, diabetes, a lower %-predicted forced expiratory volume in 1 second, heart disease, and smoking history. Adjusting for these covariates, the effect of a previous chest illness on mortality was attenuated (HR = 1.15; 0.77-1.73). CONCLUSION: In chronic SCI, chest illness in the preceding 3 years was not an independent risk factor for mortality and was not associated with level and completeness of SCI, but was associated with current smoking, physician-diagnosed COPD, and heart disease history.

A randomized controlled pilot study of a cognitive-behavioral therapy approach for painful diabetic peripheral neuropathy.

UNLABELLED: The purpose of the present pilot study was to assess the efficacy of cognitive-behavioral therapy (CBT) for painful diabetic peripheral neuropathy. This was a randomized, treatment as usual (TAU), controlled, nonblinded intervention pilot study with a 4-month follow-up conducted in a VA medical center. It was hypothesized that participants who received CBT, as compared to those who received TAU, would report significant decreases on self-report measures of pain severity, interference, and depressive symptoms from pretreatment to 4-month follow-up. Participants meeting inclusion criteria were randomly assigned to 1 of the study conditions. Of the 20 eligible participants, 12 were randomized to CBT and 8 were randomized to TAU. Participants randomized to CBT showed significant decreases on measures of pain severity (B = -.54) and pain interference (B = -.77) from pretreatment to 4-month follow-up. There were no significant changes in the TAU participants' scores on measures of pain severity (B = .00) or pain interference (B = -.09). Neither CBT nor TAU participants showed significant changes in their levels of depressive symptoms from pretreatment to 4-month follow-up. CBT may be an effective treatment approach for reducing pain severity and interference associated with painful diabetic peripheral neuropathy. PERSPECTIVE: The results of this study suggest that engaging patients in CBT for painful diabetic peripheral neuropathy may provide them the skills to become more active and experience less pain.

Chronic postconcussion symptoms and functional outcomes in OEF/OIF veterans with self-report of blast exposure.

Postconcussion symptoms (PCS) and functional outcomes were evaluated in 91 OEF/OIF outpatient veterans with reported histories of blast-exposure, with the goal of evaluating (1) the association between these outcomes and a clinical diagnosis of mild traumatic brain injury (mTBI) with or without loss of consciousness (LOC); and (2) the influence of post-traumatic stress disorder (PTSD) and depression on PCS reporting and perceived functional limitations. Individuals who reported mTBI with LOC had greater PCS complaints than individuals who reported mTBI without LOC or individuals without mTBI. However, after adjusting for severity of PTSD and depression symptoms, this group difference disappeared. Functional limitations were particularly prominent in the psychosocial domain. Again, PTSD was significantly associated with functional outcomes, but the mTBI with LOC group had greater psychosocial limitations than the other two groups, even when PTSD and depression symptoms were taken into account. These findings highlight the role of mental health in both outcomes, but additionally point to the impact of mTBI with LOC on long-term psychosocial adjustment.

Aedes (Stegomyia) aegypti and Aedes (Howardina) cozumelensis in Yucatán State, México, with a summary of published collection records for Ae. cozumelensis.

We collected mosquito immatures from artificial containers during 2010-2011 from 26 communities, ranging in size from small rural communities to large urban centers, located in different parts of Yucatán State in southeastern México. The arbovirus vector Aedes (Stegomyia) aegypti was collected from all 26 examined communities, and nine of the communities also yielded another container-inhabiting Aedes mosquito: Aedes (Howardina) cozumelensis. The communities from which Ae. cozumelensis were collected were all small rural communities (<6,000 inhabitants) in the north-central part of Yucatán State. These new collection records for Ae. cozumelensis demonstrate that this mosquito has a far broader geographic range in the Yucatán Peninsula than previously known. Ae. cozumelensis immatures were collected from both residential premises and cemeteries, with specimens recovered from rock holes as well as various artificial containers including metal cans, flower vases, buckets, tires, and a water storage tank. The co-occurrence with Ae. aegypti in small rural communities poses intriguing questions regarding linkages between these mosquitoes, including the potential for direct competition for larval development sites. Additional studies are needed to determine how commonly Ae. cozumelensis feeds on human blood and whether it is naturally infected with arboviruses or other pathogens of medical or veterinary importance. We also summarize the published records for Ae. cozumelensis, which are restricted to collections from México's Yucatán Peninsula and Belize, and uniformly represent geographic locations where Ae. aegypti can be expected to occur.

Association between sclerostin and bone density in chronic spinal cord injury.

Spinal cord injury (SCI) results in profound bone loss due to muscle paralysis and the inability to ambulate. Sclerostin, a Wnt signaling pathway antagonist produced by osteocytes, is a potent inhibitor of bone formation. Short-term studies in rodent models have shown increased sclerostin in response to mechanical unloading that is reversed with reloading. These studies suggest that complete spinal cord injury, a condition resulting in mechanical unloading of the paralyzed lower extremities, will be associated with high sclerostin levels. We assessed the relationship between circulating sclerostin and bone density in 39 subjects with chronic SCI and 10 without SCI. We found that greater total limb bone mineral content was significantly associated with greater circulating levels of sclerostin. Sclerostin levels were reduced, not elevated, in subjects with SCI who use a wheelchair compared with those with SCI who walk regularly. Similarly, sclerostin levels were lower in subjects with SCI who use a wheelchair compared with persons without SCI who walk regularly. These findings suggest that circulating sclerostin is a biomarker of osteoporosis severity, not a mediator of ongoing bone loss, in long-term, chronic paraplegia. This is in contrast to the acute sclerostin-mediated bone loss shown in animal models of mechanical unloading in which high sclerostin levels suppress bone formation. Because these data indicate important differences in the relationship between mechanical unloading, sclerostin, and bone in chronic SCI compared with short-term rodent models, it is likely that sclerostin is not a good therapeutic target to treat chronic SCI-induced osteoporosis.

Risk factors for chest illness in chronic spinal cord injury: a prospective study.

OBJECTIVE: Chest illnesses commonly cause morbidity in persons with chronic spinal cord injury. Risk factors remain poorly characterized because previous studies have not accounted for factors other than spinal cord injury. DESIGN: Between 1994 and 2005, 403 participants completed a respiratory questionnaire and underwent spirometry. Participants were contacted at a median of 1.7 yrs [interquartile range: 1.3-2.5 yrs] apart over a mean (SD) of 5.1 +/- 3.0 yrs and asked to report chest illnesses that had resulted in time off work, spent indoors, or in bed since prior contact. RESULTS: In 97 participants, there were 247 chest illnesses (0.12/person-year) with 54 hospitalizations (22%). Spinal cord injury level, completeness of injury, and duration of injury were not associated with illness risk. Adjusting for age and smoking history, any wheeze (relative risk = 1.92; 95% confidence interval: 1.19, 3.08), pneumonia or bronchitis since spinal cord injury (relative risk = 2.29; 95% confidence interval: 1.40, 3.75), and physician-diagnosed chronic obstructive pulmonary disease (relative risk = 2.17; 95% confidence interval: 1.08, 4.37) were associated with a greater risk of chest illness. Each percent-predicted decrease in forced expiratory volume in 1 sec was associated with a 1.2% increase in risk of chest illness (P = 0.030). CONCLUSIONS: In chronic spinal cord injury, chest illness resulting in time spent away from usual activities was not related to the level or completeness of spinal cord injury but was related to reduced pulmonary function, wheeze, chronic obstructive pulmonary disease, a history of pneumonia and bronchitis, and smoking.

Prevalence of chronic pain, posttraumatic stress disorder, and persistent postconcussive symptoms in OIF/OEF veterans: polytrauma clinical triad.

This study examines the prevalence and coprevalence with which returning Operation Iraqi Freedom (OIF)/Operation Enduring Freedom (OEF) veterans were reporting symptoms consistent with chronic pain, posttraumatic stress disorder (PTSD), and persistent postconcussive symptoms (PPCS). The medical records of 340 OIF/OEF veterans seen at a Department of Veterans Affairs Polytrauma Network Site were comprehensively reviewed. Analyses indicated a high prevalence of all three conditions in this population, with chronic pain, PTSD, and PPCS present in 81.5%, 68.2%, and 66.8%, respectively. Only 12 of the veterans (3.5%) had no chronic pain, PTSD, or PPCS. The frequency at which these three conditions were present in isolation (10.3%, 2.9%, and 5.3%, respectively) was significantly lower than the frequency at which they were present in combination with one another, with 42.1% of the sample being diagnosed with all three conditions simultaneously. The most common chronic pain locations were the back (58%) and head (55%). These results underscore the complexity of the presenting complaints in OIF/OEF veterans and support the importance of a multidisciplinary team approach to assessment and treatment.

Determinants of lung volumes in chronic spinal cord injury.

OBJECTIVE: To characterize determinants of lung volumes in chronic spinal cord injury (SCI). DESIGN: Cross-sectional. SETTING: VA Boston Healthcare System. PARTICIPANTS: White men (N=330) with chronic SCI. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Questionnaire responses and measurements of lung volumes. RESULTS: Adjusted for SCI severity and stature, greater body mass index (BMI) was associated (all P<.05) with lower total lung capacity (TLC) (-38.7 mL x kg(-1) x m(-2)), functional residual capacity (FRC) (-73.9 mL x kg(-1) x m(-2)), residual volume (RV) (-40.4 mL x kg(-1) x m(-2)), and expiratory reserve volume (ERV) (-32.2 mL x kg(-1) x m(-2)). The effect of BMI on RV was most pronounced in quadriplegia (-72 mL x kg(-1) x m(-2)). Lifetime smoking was associated with a greater FRC (5.3 mL/pack-year) and RV (3.1 mL/pack-years). The effects of lifetime smoking were also greatest in quadriplegia (11 mL/pack-year for FRC; 7.8 mL/pack-year for RV). Time since injury, independent of age, was associated with a decrease in TLC, FRC, ERV, and RV (P<.05). Age was not a predictor of TLC once time since injury was considered. CONCLUSIONS: Determinants of FRC, TLC, ERV, and RV in chronic SCI include factors related and unrelated to SCI. The mechanisms remain to be determined but likely involve the elastic properties and muscle function of the respiratory system and perhaps the effects of systemic inflammation related to adiposity. Addressing modifiable factors such as obesity, muscle stiffness, and smoking may improve respiratory morbidity and mortality in SCI by improving pulmonary function.