Table 2 Smoking status and global brain volumes in the CARDIA brain MRI cohort

From: Cigarette smoking and gray matter brain volumes in middle age adults: the CARDIA Brain MRI sub-study

  Total brain volume Total white matter volume Total gray matter volume
Beta 95% CI p Beta 95% CI p Beta 95% CI p
Basic model: demographics, intracranial volume
Never-smokers Ref.    Ref.    Ref.   
Former-smokers −1.72 −6.55, 3.10 0.49 1.80 −2.25, 5.86 0.38 −3.52 −7.12, 0.07 0.05
Current smokers −9.23 −15.38, −3.09 0.003 −0.37 −5.53, 4.79 0.89 −8.86 −13.44, −4.29 0.0002
Vascular factors model: demographics, intracranial volume, vascular risk factors
Never-smokers Ref.    Ref.    Ref.   
Former-smokers −1.04 −6.21, 3.41 0.57 1.95 −.118, 6.02 0.35 −3.35 −6.95, 0.25 0.07
Current smokers −8.36 −14.53, −2.19 0.008 −0.030 −5.24, 5.18 0.99 −8.33 −12.94, −3.72 0.0004
Respiratory factors model: demographics, intracranial volume, respiratory factors (respiratory illnesses+FEV1)
Never-smokers Ref.    Ref.    Ref.   
Former-smokers −1.58 −6.57, 3.41 0.54 1.58 −2.62, 5.77 0.46 −3.15 −6.88, 0.58 0.10
Current smokers −9.06 −15.69, −2.42 0.008 −1.37 −6.95, 4.21 0.63 −7.69 −6.95, 4.21 0.002
Substance use/psychological factors model: demographics, intracranial volume, substance use/psychological factors
Never-smokers Ref.    Ref.    Ref.   
Former-smokers 0.24 −4.78, 5.27 0.93 2.04 −2.23, 6.30 0.35 −1.80 −5.52, 1.93 0.34
Current smokers −5.24 −11.69, 1.21 0.11 0.30 −5.18, 5.77 0.92 −5.54 −10.32, −0.76 0.02
  1. Basic model adjusted for age, sex, education, race, study center, and total intracranial volume, n = 698
  2. Vascular factors model adjusted for age, sex, education, study center, race, and total intracranial volume, hypertension, diabetes, history of vascular disorders, BMI, and high cholesterol, n = 698
  3. Respiratory factors adjusted for age, sex, education, race, study center, and total intracranial volume, respiratory illness, and FEV1, n = 643 (sub-sample with spirometer data)
  4. Substance use/psychological factors model adjusted for age, sex, education, race, and total intracranial volume, alcohol consumption, depressive symptoms, and illicit drug use, n = 698
  5. Bold values: We were highlighting the statistically significant results