Table 2.
Unadjusted hazard ratios for firearm and non-firearm suicide among Millennium Cohort Study participants.
| Firearm suicide |
Non-firearm suicide |
|||||
|---|---|---|---|---|---|---|
| HR | 95% CI | p | HR | 95% CI | p | |
| Demographic factors | ||||||
| Age (5-year increments) | 0.82 | (0.76, 0.88) | <0.0001 | 0.91 | (0.83, 1.00) | 0.052 |
| Sex (ref: Female) | 3.04 | (2.20, 4.20) | <0.0001 | 1.47 | (1.03, 2.11) | 0.035 |
| Race/Ethnicity (Ref: White, non-Hispanic) | 0.0035 | 0.026 | ||||
| Asian, Pacific Islander, American Indian, Alaska Native, or Multiracial | 0.61 | (0.36, 1.03) | 1.35 | (0.80, 2.27) | ||
| Black, non-Hispanic | 0.55 | (0.37, 0.83) | 0.40 | (0.20, 0.78) | ||
| Hispanic | 0.64 | (0.39, 1.02) | 0.88 | (0.49, 1.59) | ||
| Educational attainment (Ref: ≥Bachelor's degree) | <0.0001 | 0.0014 | ||||
| High school degree or less | 3.10 | (2.15, 4.48) | 2.40 | (1.50, 3.86) | ||
| Some college/Associate's degree | 2.39 | (1.70, 3.36) | 1.77 | (1.15, 2.74) | ||
| Marital status (Ref: Married) | 0.0031 | 0.0009 | ||||
| Never married | 1.48 | (1.18, 1.86) | 1.56 | (1.11, 2.18) | ||
| Divorced/Separated/Widowed | 1.09 | (0.75, 1.57) | 2.13 | (1.40, 3.25) | ||
| Panel (Ref: Panel 1, 2001–2003) | <0.0001 | 0.065 | ||||
| Panel 2 (2004–2006) | 1.13 | (0.79, 1.61) | 1.21 | (0.78, 1.86) | ||
| Panel 3 (2007–2008) | 2.30 | (1.70, 3.12) | 1.03 | (0.66, 1.61) | ||
| Panel 4 (2011–2013) | 2.94 | (2.09, 4.12) | 1.85 | (1.15, 2.95) | ||
| Military characteristics | ||||||
| Service component (Ref: Reserve/National Guard) | ||||||
| Active duty | 1.21 | (0.96, 1.53) | 0.105 | 1.34 | (0.96, 1.86) | 0.086 |
| Rank (Ref: Officer) | ||||||
| Enlisted | 2.28 | (1.56, 3.34) | <0.0001 | 1.95 | (1.18, 3.22) | 0.0092 |
| Service branch (Ref: Air Force) | <0.0001 | 0.0062 | ||||
| Army | 1.39 | (1.07, 1.81) | 1.86 | (1.25, 2.78) | ||
| Navy/Coast Guard | 0.60 | (0.40, 0.92) | 1.20 | (0.71, 2.04) | ||
| Marine Corps | 2.02 | (1.41, 2.91) | 2.07 | (1.17, 3.66) | ||
| Deployment/combat experience (Ref: Deployed, no combat) | 0.046 | 0.017 | ||||
| Not deployed | 1.20 | (0.84, 1.73) | 2.47 | (1.34, 4.55) | ||
| Deployed, combat | 1.53 | (1.08, 2.16) | 2.31 | (1.26, 4.24) | ||
| Deployed, combat unknown | 1.71 | (0.77, 3.83) | 3.98 | (1.40, 11.29) | ||
| Health behaviors and psychosocial factors | ||||||
| Smoking Status (Ref: Never smoked) | <0.0001 | <0.0001 | ||||
| Previously smoked | 1.89 | (1.44, 2.49) | 2.60 | (1.78, 3.80) | ||
| Currently smokes | 2.82 | (2.18, 3.66) | 3.00 | (2.05, 4.40) | ||
| Alcohol-related problemsa | 2.40 | (1.87, 3.07) | <0.0001 | 2.47 | (1.75, 3.50) | <0.0001 |
| Risky drinkingb | 1.72 | (1.36, 2.16) | <0.0001 | 1.61 | (1.17, 2.23) | 0.0038 |
| Sleep duration (Ref: 7–9 h) | <0.0001 | 0.0005 | ||||
| <6 h/>10 h | 1.98 | (1.54, 2.55) | 1.86 | (1.31, 2.65) | ||
| 6 h | 1.01 | (0.76, 1.34) | 0.97 | (0.66, 1.44) | ||
| Life stressorsc | 1.26 | (1.01, 1.57) | 0.040 | 1.81 | (1.32, 2.47) | 0.0002 |
| Social support (Ref: Not bothered) | <0.0001 | <0.0001 | ||||
| Bothered a little | 1.60 | (1.21, 2.10) | 1.52 | (1.02, 2.26) | ||
| Bothered a lot | 2.18 | (1.52, 3.11) | 2.90 | (1.85, 4.55) | ||
| Physical health factors | ||||||
| BMI (Ref: Normal weight, <25.0 kg/m2) | 0.339 | 0.035 | ||||
| Overweight (25.0, −29.99 kg/m2) | 0.90 | (0.72, 1.14) | 0.65 | (0.47, 0.90) | ||
| Obese (>30.0 kg/m2) | 0.75 | (0.50, 1.13) | 0.81 | (0.48, 1.36) | ||
| Bodily pain (Ref: Low) | 0.0008 | 0.0029 | ||||
| Medium | 1.26 | (0.94, 1.70) | 0.94 | (0.62, 1.42) | ||
| High | 1.73 | (1.28, 2.32) | 1.65 | (1.11, 2.44) | ||
| Multiple somatic symptoms (Ref: None/mild) | ||||||
| Moderate/severe | 1.56 | (1.25, 1.93) | <0.0001 | 1.84 | (1.35, 2.50) | 0.0001 |
| Mental Health Factors | ||||||
| Probable PTSD (PCL-C)d | 3.15 | (2.37, 4.19) | <0.0001 | 3.59 | (2.45, 5.27) | <0.0001 |
| History of PTSD diagnosis | 3.34 | (2.32, 4.81) | <0.0001 | 2.42 | (1.34, 4.36) | 0.0033 |
| Probable depression (PHQ-8)e | 3.55 | (2.59, 4.86) | <0.0001 | 2.52 | (1.52, 4.16) | 0.0003 |
| History of major depression diagnosis | 2.43 | (1.85, 3.20) | <0.0001 | 4.16 | (2.97, 5.82) | <0.0001 |
| Probable panic/anxiety (PHQ)f | 2.83 | (2.01, 3.99) | <0.0001 | 3.78 | (2.45, 5.83) | <0.0001 |
| History of bipolar diagnosis | 2.25 | (1.00, 5.05) | 0.049 | 9.50 | (5.28, 17.10) | <0.0001 |
PCL-C, PTSD checklist-Civilian Version; PHQ, Patient Health Questionnaire; PTSD, posttraumatic stress disorder.
a
Endorsement of one or more item on the PHQ alcohol items.
b
Assessed based on >14 drinks per week for men (>7 drinks per week for women) or ≥5 drinks for men (≥4 drinks for women) in one given day of the week or ≥5 drinks on at least one day or occasion during the past year.
c
Endorsed one of more of the following: disabling illness/injury, divorce/separation, major financial problems, violent assault, sexual harassment, sexual assault.
d
Assessed using the PCL-C.
e
Assessed using the PHQ depression items.
f
Assessed using the PHQ panic syndrome and other anxiety items.