Pain Medicine 2015; 16: 1690–1696 Wiley Periodicals, Inc.
Smoking Status and Pain Intensity Among OEF/OIF/OND Veterans
†
*Bryant University, Smithfield, Rhode Island; VA Connecticut Healthcare System, West Haven, Connecticut; ‡Yale University School of Medicine, New Haven, Connecticut; §VA Central Western Massachusetts Healthcare System, Leeds, Massachusetts; ¶ University of Massachusetts Medical School, Worcester, Massachusetts; **University of Connecticut Health Center, Farmington, Connecticut Reprint requests to: Lori Bastian MD, MPH, VA Connecticut Healthcare System, West Haven Campus Research Office/151, 950 Campbell Avenue, West Haven, CT 06516-2770, USA, Tel: 860-667-6853; E-mail: [email protected]. Disclosures: This material is based upon work supported by the Department of Veterans Affairs, Veterans Health Administration, Office of Research and Development, and Health Services Research and Development # IIR 12-118. Disclaimer: The views expressed in this manuscript are those of the authors and do not necessarily reflect the position or policy of the Department of Veterans Affairs or the United States Government. Conflicts of interests: There are no conflicts to disclose.
tions have reported higher pain intensity among current smokers compared with nonsmokers and former smokers. We examined the association of smoking status with reported pain intensity among Veterans of Operations Enduring Freedom, Iraqi Freedom, and New Dawn (OEF/OIF/OND). Design. The sample consisted of OEF/OIF/OND Veterans who had at least one visit to Veterans Affairs (2001–2012) with information in the electronic medical record for concurrent smoking status and pain intensity. The primary outcome measure was current pain intensity, categorized as none to mild (0–3); moderate (4–6); or severe (7); based on a selfreported 11-point pain numerical rating scale. Multivariable logistic regression analyses were used to assess the association of current smoking status with moderate to severe (4) pain intensity, controlling for potential confounders. Results. Overall, 50,988 women and 355,966 men Veterans were examined. The sample mean age was 30 years; 66.3% reported none to mild pain; 19.8% moderate pain; and 13.9% severe pain; 37% were current smokers and 16% former smokers. Results indicated that current smoking [odds ratio (OR) 5 1.29 (95% confidence intervals (CI) 5 1.27–1.31)] and former smoking [OR 5 1.02 (95% CI 5 1.01–1.05)] were associated with moderate to severe pain intensity, controlling for age, service-connected disability, gender, obesity, substance abuse, mood disorders, and Post Traumatic Stress Disorder. Conclusions. We found an association between current smoking and pain intensity. This effect was attenuated in former smokers. Our study highlights the importance of understanding reported pain intensity in OEF/OIF/OND Veterans who continue to smoke. Key Words. Pain; Tobacco; Smoking; Veterans
Abstract
Introduction
Objective. Pain and smoking are highly prevalent among Veterans. Studies in non-Veteran popula-
Smoking is highly prevalent among Veterans recently separated from active duty [1,2] and is a major cause of
1690
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Julie E. Volkman, PhD,* Eric C. DeRycke, MPH,† Mary A. Driscoll, PhD,† William C. Becker, MD,†,‡ Cynthia A. Brandt, MD, MPH,†,‡ Kristin M. Mattocks, PhD, MPH,§,¶ Sally G. Haskell, MD,†,‡ Harini Bathulapalli, MSc, MPH,† Joseph L. Goulet, PhD,†,‡ and Lori A. Bastian, MD, MPH,†,**
Smoking and Pain Among Veterans excess morbidity, mortality, and loss in productivity [3]. The highest rates of smoking are observed among Veterans born between 1985 and 1989 (40% men; 44% women) and U.S. service members deployed to Iraq and Afghanistan smoking twice as much as other Americans [1–4]. These high prevalence rates decrease overtime, more rapidly in women Veterans; but nevertheless, Veterans maintain a higher smoking prevalence than their non-Veteran counterparts [1].
Previous research with non-Veterans (both populationbased studies and clinical studies of patients with chronic pain) suggests that smoking is associated with concurrent pain intensity across the lifespan, such that smokers with chronic pain have higher pain intensity and greater functional impairment than nonsmokers [12–19]. Moreover, the link between pain and smoking is likely bidirectional. In a recent synthesis, Ditre and Brandon hypothesized a reciprocal model of pain and smoking fueled by myriad social, biological, and physiological factors in which pain and smoking exacerbate each other resulting in a positive feedback loop of more pain and increased smoking [20]. This association between smoking and pain is particularly strong in adolescents and young adults [17,21]. While there is growing support for the link between smoking and pain in the published literature, studies have not examined this association in Veteran cohorts. We conducted an analysis of OEF/OIF/OND Veterans to determine whether smoking status is associated with pain intensity. As the largest integrated health system in the U.S. caring for individuals throughout their lifespan, the Veterans Health Administration (VHA) has a strong interest in understanding risk factors associated with pain intensity and treatments targeting those risk factors. The current investigation represents a unique opportunity to explore the patterns and correlates of smoking and pain in a large cohort of Veterans who used the VHA national system of care [7]. We aim to: (1) characterize the patterns and prevalence of smoking and pain in OEF/OIF/OND Veterans; and (2) examine the covariates of smoking and pain in Veterans. Methods Study Design/Population The sampling frame for the overall study is the OEF/OIF/ OND roster, provided to the VA by the Department of
Data Sources Data on eligible Veterans were linked to VHA administrative and clinical data contained within the National Patient Care Database, Decision Support Systems, and the Corporate Data Warehouse. These databases provide a record of inpatient and outpatient health care encounters and coded diagnostic conditions (based on the International Classification of Diseases, Ninth Revision [ICD-9]). Demographics were obtained from the Department of Defense OEF/OIF/OND roster. Smoking Variable Veterans were categorized as current, former, and never smokers based on a comprehensive algorithm that includes text entries and clinical reminders using McGinnis et al. [22] methodology. Pain Variable Consistent with the VHA’s “Pain as the 5th Vital Sign” initiative [23], patients presenting to VHA primary care clinics are screened for the presence and intensity of pain using a 0–10 numeric rating scale (NRS). Veterans are asked to “rate your current pain on a 0 (no pain) to 10 (worst pain imaginable) scale,” and the NRS pain intensity rating is then recorded in the Veteran’s electronic medical record (EMR) with other vital sign data. The highest concurrent pain score (within 630 days of smoking status) was recorded into our dataset. Pain intensity was categorized as mild (0–3); moderate (4–6); or severe (7) [24]. Related Variables Demographic variables including age, sex, race/ethnicity (i.e., Black, Hispanic, other/unknown, White), serviceconnected disability, education (high school diploma or the equivalent, greater than high school), and military characteristics including rank (enlisted, officer), branch (Army, Navy, Marine Corps, Air Force), and status (Active duty, National Guard, Reserve) were also examined. These data were extracted as close to the time of enrollment in VHA care. 1691
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Pain is reported by more than one-third of Operations Enduring Freedom, Iraqi Freedom, and New Dawn (OEF/OIF/OND) Veterans [5–8]. Considerable research suggests that there are gender-related differences in the experience of clinical pain [9]. Additionally, women are overrepresented in a number of chronic pain disorders and they experience more frequent and severe painrelated symptoms than men [10,11]. Other risk factors for pain among Veterans include obesity and mental health disorders such as PTSD and depression [7].
Defense Manpower Data Center’s (DMDC) Contingency Tracking System. The OEF/OIF/OND roster is a list of Veterans who separated from OEF/OIF/OND military service and enrolled in VA healthcare between October 1, 2001 and September 30, 2012 (n 5 625,082). It includes information on Veterans’ sex, race, date of birth, service-connected disability, date of last deployment, armed forces branch (Army, Navy, Air Force, or Marine Corps), and component (National Guard, Reserve, or active duty). Our analyses included Veterans on the roster who had one or more VHA primary care visits. The study was approved by the Human Investigation Committees at VA Connecticut Healthcare System—West Haven and Yale University School of Medicine.
Volkman et al. Mental Health Conditions We used the Agency for Healthcare Research and Quality’s (AHRQ) Clinical Classifications Software (CCS) ICD9 codes to identify mental health conditions [25]. We examined the following conditions based on their relatively high prevalence in Veteran populations and their frequent comorbidity with painful conditions: anxiety disorders (i.e., anxiety disorder not otherwise specified [NOS], panic disorder, generalized anxiety disorder, agoraphobia with and without panic, other anxiety states), mood disorders (i.e., major depressive disorder, depressive disorder NOS, dysthymia, bipolar disorder), PTSD, and substance use disorders (i.e., alcohol and drug abuse or dependence). Body Mass Index
Pain Diagnoses We included diagnostic code groupings for back problems (e.g., backache, cervicalgia, degeneration of lumbar, lumbosacral, or intervertebral disc), joint disorders (e.g., joint involving lower leg, pain in joint involving ankle and foot, pain in joint involving shoulder region, pain in joint unspecified, and pain in joint involving pelvic region and thigh), musculoskeletal/connective tissue disorders (e.g., limb pain, plantar fascial fibromatosis, myalgia, and myositis), osteoarthritis, headache (e.g., migraine, tension headache), and peripheral neuropathy [AHRQ ICD-9]. ICD-9 codes examined in this study included, ICD-9 (710–719), (720–724), (725–739), (307.89), (846), (847), (805), (806), (346), (307.81), (784), (337.23), (729.1), (524.6), (356) [7].
In unadjusted analyses, Veterans with moderate to severe pain intensity were significantly older, and were more likely to be: male have a service-connected disability, and be current smokers (P’s < 0.0001; Table 2). Veterans with moderate to severe pain intensity were more likely to have a mental health diagnosis of mood disorder, PTSD, or substance abuse, along with obesity (P < 0.0001; Table 2). Results of adjusted models revealed that current smoking [odds ratio (OR) 5 1.29 (95% confidence intervals (CI) 5 1.27–1.31)] and former smoking [OR 5 1.02 (95% CI 5 1.01–1.05)] were associated with a higher odds of reporting moderate to severe pain intensity after controlling for age [OR 5 1.0004 (95% CI 5 1.0003–1.0004)], gender [OR 5 1.04 (95% CI 5 1.02–1.06)], serviceconnection [OR 5 1.76 (95% CI 5 1.74–1.80), substance abuse [OR 5 1.19 (95% CI 5 1.16–1.22)], mood disorders [OR 5 1.28 (95% CI 5 1.25–1.31)], PTSD [OR 5 1.70 (95% CI 5 1.68–1.73)], and obesity [OR 5 1.18 (95% CI 5 1.17–1.20)] (Table 2). In a subgroup analysis by gender (Table 3), we observed higher pain severity for current smokers in both men and women Veterans. We did not find a significant interaction term between current smoking and gender (data are not shown). Discussion
Analysis We used the v2 test to compare factors associated with self-reported pain. Statistical analyses were performed using SAS version 9.4 (SAS, Inc., Cary, NC). Logistic regression was used to examine the association of current and former smoking status with self-reported pain intensity, controlling for potential confounders such as age, gender, service-connected disability, BMI, and mental health diagnoses (substance abuse, mood disorders, and PTSD). We also conducted a subgroup analysis to examine potential gender differences. Results Overall, the OEF/OIF/OND roster contained 406,954 Veterans meeting our inclusion criteria and 12.1% were women Veterans (n 5 50,988). The mean age was 30.1 1692
To our knowledge, this analysis is the first report to examine the association of smoking and pain among OEF/OIF/OND Veterans. As hypothesized, and consistent with studies in non-Veteran samples, we found current smokers were more likely to report moderate to severe pain intensity compared with nonsmokers [27]. This effect was attenuated in former smokers. Due to the cross-sectional design of this study, it remains unclear whether smoking may have increased pain intensity or if the pain experience resulted in continued smoking. Researchers have described this bidirectional model [20] and this study highlights the importance of understanding reported pain intensity in OEF/OIF/OND Veterans who continue to smoke. In our study, older age of Veterans was related to pain intensity. Given the young age of the cohort
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Body mass index (BMI) was extracted at the initial primary care clinic visit following enrollment in VHA care during Year 1 or, if unavailable, the first height and weight recorded in the EMR were used to calculate BMI (kg/m2). Using standard a classification, Veterans were categorized as obese (BMI 30) or nonobese (BMI < 30) [26].
years (SD 5 9.3). The ethnic/racial composition of the sample was as follows: 60.2% Caucasian, 15.5% African American, 11.2% Hispanic, and 13.0% “Other” or “Unknown”. With regards to smoking status, 37% and 16% of Veterans were categorized as current and former smokers, respectively. The majority of Veterans (66.3%) reported none to mild pain; 19.8% reported moderate pain and 13.9% reported severe pain. Veterans with moderate and severe pain were more likely to have a ICD-9 pain diagnosis compared with Veterans with none to mild pain (Table 1). Demographics, military characteristics, and mental health diagnoses are reported in Table 1.
Smoking and Pain Among Veterans
Table 1
Characteristics of Veterans by pain intensity level (n 5 406,954) Moderate Pain 4–6
Severe Pain 7–10
(n 5 269,904)
(n 5 80,413)
(n 5 56,637)
P Value
30.0 (9.34)
30.3 (9.2)
30.1 (9.2)
Smoking Status and Pain Intensity Among OEF/OIF/OND Veterans
†
*Bryant University, Smithfield, Rhode Island; VA Connecticut Healthcare System, West Haven, Connecticut; ‡Yale University School of Medicine, New Haven, Connecticut; §VA Central Western Massachusetts Healthcare System, Leeds, Massachusetts; ¶ University of Massachusetts Medical School, Worcester, Massachusetts; **University of Connecticut Health Center, Farmington, Connecticut Reprint requests to: Lori Bastian MD, MPH, VA Connecticut Healthcare System, West Haven Campus Research Office/151, 950 Campbell Avenue, West Haven, CT 06516-2770, USA, Tel: 860-667-6853; E-mail: [email protected]. Disclosures: This material is based upon work supported by the Department of Veterans Affairs, Veterans Health Administration, Office of Research and Development, and Health Services Research and Development # IIR 12-118. Disclaimer: The views expressed in this manuscript are those of the authors and do not necessarily reflect the position or policy of the Department of Veterans Affairs or the United States Government. Conflicts of interests: There are no conflicts to disclose.
tions have reported higher pain intensity among current smokers compared with nonsmokers and former smokers. We examined the association of smoking status with reported pain intensity among Veterans of Operations Enduring Freedom, Iraqi Freedom, and New Dawn (OEF/OIF/OND). Design. The sample consisted of OEF/OIF/OND Veterans who had at least one visit to Veterans Affairs (2001–2012) with information in the electronic medical record for concurrent smoking status and pain intensity. The primary outcome measure was current pain intensity, categorized as none to mild (0–3); moderate (4–6); or severe (7); based on a selfreported 11-point pain numerical rating scale. Multivariable logistic regression analyses were used to assess the association of current smoking status with moderate to severe (4) pain intensity, controlling for potential confounders. Results. Overall, 50,988 women and 355,966 men Veterans were examined. The sample mean age was 30 years; 66.3% reported none to mild pain; 19.8% moderate pain; and 13.9% severe pain; 37% were current smokers and 16% former smokers. Results indicated that current smoking [odds ratio (OR) 5 1.29 (95% confidence intervals (CI) 5 1.27–1.31)] and former smoking [OR 5 1.02 (95% CI 5 1.01–1.05)] were associated with moderate to severe pain intensity, controlling for age, service-connected disability, gender, obesity, substance abuse, mood disorders, and Post Traumatic Stress Disorder. Conclusions. We found an association between current smoking and pain intensity. This effect was attenuated in former smokers. Our study highlights the importance of understanding reported pain intensity in OEF/OIF/OND Veterans who continue to smoke. Key Words. Pain; Tobacco; Smoking; Veterans
Abstract
Introduction
Objective. Pain and smoking are highly prevalent among Veterans. Studies in non-Veteran popula-
Smoking is highly prevalent among Veterans recently separated from active duty [1,2] and is a major cause of
1690
Downloaded from http://painmedicine.oxfordjournals.org/ by guest on June 5, 2016
Julie E. Volkman, PhD,* Eric C. DeRycke, MPH,† Mary A. Driscoll, PhD,† William C. Becker, MD,†,‡ Cynthia A. Brandt, MD, MPH,†,‡ Kristin M. Mattocks, PhD, MPH,§,¶ Sally G. Haskell, MD,†,‡ Harini Bathulapalli, MSc, MPH,† Joseph L. Goulet, PhD,†,‡ and Lori A. Bastian, MD, MPH,†,**
Smoking and Pain Among Veterans excess morbidity, mortality, and loss in productivity [3]. The highest rates of smoking are observed among Veterans born between 1985 and 1989 (40% men; 44% women) and U.S. service members deployed to Iraq and Afghanistan smoking twice as much as other Americans [1–4]. These high prevalence rates decrease overtime, more rapidly in women Veterans; but nevertheless, Veterans maintain a higher smoking prevalence than their non-Veteran counterparts [1].
Previous research with non-Veterans (both populationbased studies and clinical studies of patients with chronic pain) suggests that smoking is associated with concurrent pain intensity across the lifespan, such that smokers with chronic pain have higher pain intensity and greater functional impairment than nonsmokers [12–19]. Moreover, the link between pain and smoking is likely bidirectional. In a recent synthesis, Ditre and Brandon hypothesized a reciprocal model of pain and smoking fueled by myriad social, biological, and physiological factors in which pain and smoking exacerbate each other resulting in a positive feedback loop of more pain and increased smoking [20]. This association between smoking and pain is particularly strong in adolescents and young adults [17,21]. While there is growing support for the link between smoking and pain in the published literature, studies have not examined this association in Veteran cohorts. We conducted an analysis of OEF/OIF/OND Veterans to determine whether smoking status is associated with pain intensity. As the largest integrated health system in the U.S. caring for individuals throughout their lifespan, the Veterans Health Administration (VHA) has a strong interest in understanding risk factors associated with pain intensity and treatments targeting those risk factors. The current investigation represents a unique opportunity to explore the patterns and correlates of smoking and pain in a large cohort of Veterans who used the VHA national system of care [7]. We aim to: (1) characterize the patterns and prevalence of smoking and pain in OEF/OIF/OND Veterans; and (2) examine the covariates of smoking and pain in Veterans. Methods Study Design/Population The sampling frame for the overall study is the OEF/OIF/ OND roster, provided to the VA by the Department of
Data Sources Data on eligible Veterans were linked to VHA administrative and clinical data contained within the National Patient Care Database, Decision Support Systems, and the Corporate Data Warehouse. These databases provide a record of inpatient and outpatient health care encounters and coded diagnostic conditions (based on the International Classification of Diseases, Ninth Revision [ICD-9]). Demographics were obtained from the Department of Defense OEF/OIF/OND roster. Smoking Variable Veterans were categorized as current, former, and never smokers based on a comprehensive algorithm that includes text entries and clinical reminders using McGinnis et al. [22] methodology. Pain Variable Consistent with the VHA’s “Pain as the 5th Vital Sign” initiative [23], patients presenting to VHA primary care clinics are screened for the presence and intensity of pain using a 0–10 numeric rating scale (NRS). Veterans are asked to “rate your current pain on a 0 (no pain) to 10 (worst pain imaginable) scale,” and the NRS pain intensity rating is then recorded in the Veteran’s electronic medical record (EMR) with other vital sign data. The highest concurrent pain score (within 630 days of smoking status) was recorded into our dataset. Pain intensity was categorized as mild (0–3); moderate (4–6); or severe (7) [24]. Related Variables Demographic variables including age, sex, race/ethnicity (i.e., Black, Hispanic, other/unknown, White), serviceconnected disability, education (high school diploma or the equivalent, greater than high school), and military characteristics including rank (enlisted, officer), branch (Army, Navy, Marine Corps, Air Force), and status (Active duty, National Guard, Reserve) were also examined. These data were extracted as close to the time of enrollment in VHA care. 1691
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Pain is reported by more than one-third of Operations Enduring Freedom, Iraqi Freedom, and New Dawn (OEF/OIF/OND) Veterans [5–8]. Considerable research suggests that there are gender-related differences in the experience of clinical pain [9]. Additionally, women are overrepresented in a number of chronic pain disorders and they experience more frequent and severe painrelated symptoms than men [10,11]. Other risk factors for pain among Veterans include obesity and mental health disorders such as PTSD and depression [7].
Defense Manpower Data Center’s (DMDC) Contingency Tracking System. The OEF/OIF/OND roster is a list of Veterans who separated from OEF/OIF/OND military service and enrolled in VA healthcare between October 1, 2001 and September 30, 2012 (n 5 625,082). It includes information on Veterans’ sex, race, date of birth, service-connected disability, date of last deployment, armed forces branch (Army, Navy, Air Force, or Marine Corps), and component (National Guard, Reserve, or active duty). Our analyses included Veterans on the roster who had one or more VHA primary care visits. The study was approved by the Human Investigation Committees at VA Connecticut Healthcare System—West Haven and Yale University School of Medicine.
Volkman et al. Mental Health Conditions We used the Agency for Healthcare Research and Quality’s (AHRQ) Clinical Classifications Software (CCS) ICD9 codes to identify mental health conditions [25]. We examined the following conditions based on their relatively high prevalence in Veteran populations and their frequent comorbidity with painful conditions: anxiety disorders (i.e., anxiety disorder not otherwise specified [NOS], panic disorder, generalized anxiety disorder, agoraphobia with and without panic, other anxiety states), mood disorders (i.e., major depressive disorder, depressive disorder NOS, dysthymia, bipolar disorder), PTSD, and substance use disorders (i.e., alcohol and drug abuse or dependence). Body Mass Index
Pain Diagnoses We included diagnostic code groupings for back problems (e.g., backache, cervicalgia, degeneration of lumbar, lumbosacral, or intervertebral disc), joint disorders (e.g., joint involving lower leg, pain in joint involving ankle and foot, pain in joint involving shoulder region, pain in joint unspecified, and pain in joint involving pelvic region and thigh), musculoskeletal/connective tissue disorders (e.g., limb pain, plantar fascial fibromatosis, myalgia, and myositis), osteoarthritis, headache (e.g., migraine, tension headache), and peripheral neuropathy [AHRQ ICD-9]. ICD-9 codes examined in this study included, ICD-9 (710–719), (720–724), (725–739), (307.89), (846), (847), (805), (806), (346), (307.81), (784), (337.23), (729.1), (524.6), (356) [7].
In unadjusted analyses, Veterans with moderate to severe pain intensity were significantly older, and were more likely to be: male have a service-connected disability, and be current smokers (P’s < 0.0001; Table 2). Veterans with moderate to severe pain intensity were more likely to have a mental health diagnosis of mood disorder, PTSD, or substance abuse, along with obesity (P < 0.0001; Table 2). Results of adjusted models revealed that current smoking [odds ratio (OR) 5 1.29 (95% confidence intervals (CI) 5 1.27–1.31)] and former smoking [OR 5 1.02 (95% CI 5 1.01–1.05)] were associated with a higher odds of reporting moderate to severe pain intensity after controlling for age [OR 5 1.0004 (95% CI 5 1.0003–1.0004)], gender [OR 5 1.04 (95% CI 5 1.02–1.06)], serviceconnection [OR 5 1.76 (95% CI 5 1.74–1.80), substance abuse [OR 5 1.19 (95% CI 5 1.16–1.22)], mood disorders [OR 5 1.28 (95% CI 5 1.25–1.31)], PTSD [OR 5 1.70 (95% CI 5 1.68–1.73)], and obesity [OR 5 1.18 (95% CI 5 1.17–1.20)] (Table 2). In a subgroup analysis by gender (Table 3), we observed higher pain severity for current smokers in both men and women Veterans. We did not find a significant interaction term between current smoking and gender (data are not shown). Discussion
Analysis We used the v2 test to compare factors associated with self-reported pain. Statistical analyses were performed using SAS version 9.4 (SAS, Inc., Cary, NC). Logistic regression was used to examine the association of current and former smoking status with self-reported pain intensity, controlling for potential confounders such as age, gender, service-connected disability, BMI, and mental health diagnoses (substance abuse, mood disorders, and PTSD). We also conducted a subgroup analysis to examine potential gender differences. Results Overall, the OEF/OIF/OND roster contained 406,954 Veterans meeting our inclusion criteria and 12.1% were women Veterans (n 5 50,988). The mean age was 30.1 1692
To our knowledge, this analysis is the first report to examine the association of smoking and pain among OEF/OIF/OND Veterans. As hypothesized, and consistent with studies in non-Veteran samples, we found current smokers were more likely to report moderate to severe pain intensity compared with nonsmokers [27]. This effect was attenuated in former smokers. Due to the cross-sectional design of this study, it remains unclear whether smoking may have increased pain intensity or if the pain experience resulted in continued smoking. Researchers have described this bidirectional model [20] and this study highlights the importance of understanding reported pain intensity in OEF/OIF/OND Veterans who continue to smoke. In our study, older age of Veterans was related to pain intensity. Given the young age of the cohort
Downloaded from http://painmedicine.oxfordjournals.org/ by guest on June 5, 2016
Body mass index (BMI) was extracted at the initial primary care clinic visit following enrollment in VHA care during Year 1 or, if unavailable, the first height and weight recorded in the EMR were used to calculate BMI (kg/m2). Using standard a classification, Veterans were categorized as obese (BMI 30) or nonobese (BMI < 30) [26].
years (SD 5 9.3). The ethnic/racial composition of the sample was as follows: 60.2% Caucasian, 15.5% African American, 11.2% Hispanic, and 13.0% “Other” or “Unknown”. With regards to smoking status, 37% and 16% of Veterans were categorized as current and former smokers, respectively. The majority of Veterans (66.3%) reported none to mild pain; 19.8% reported moderate pain and 13.9% reported severe pain. Veterans with moderate and severe pain were more likely to have a ICD-9 pain diagnosis compared with Veterans with none to mild pain (Table 1). Demographics, military characteristics, and mental health diagnoses are reported in Table 1.
Smoking and Pain Among Veterans
Table 1
Characteristics of Veterans by pain intensity level (n 5 406,954) Moderate Pain 4–6
Severe Pain 7–10
(n 5 269,904)
(n 5 80,413)
(n 5 56,637)
P Value
30.0 (9.34)
30.3 (9.2)
30.1 (9.2)
