Table 1 Participant characteristics.
From: Associations of cigarette smoking with gray and white matter in the UK Biobank
Gray matter analyses | White matter analyses | |||
|---|---|---|---|---|
Characteristic | N / M | % | N / M | % |
Total N | 19615 | 17760 | ||
Smoking variables | ||||
Smoking status (current; former; never)a | 369; 3873; 15373 | 1.9%; 19.7%; 78.4% | 312; 3460; 13988 | 1.8%; 19.5%; 78.6% |
Cigarettes per dayb | 17.1 (SD = 8.9) | 17.0 (SD = 8.9) | ||
Durationb | 22.9 (SD = 12.9) | 22.7 (SD = 12.8) | ||
Covariates | ||||
Age | 62.9 (SD = 7.5) | 62.9 (SD = 7.4) | ||
Female | 10503 | 53.5% | 9565 | 53.9% |
Ethnicity (non-White) | 543 | 2.8% | 473 | 2.7% |
Income | £31000-£51,999c (IQR: £18,000-£100,000) | £31,000-£51,999c (IQR: £18,000-£100,000) | ||
College degree | 9287 | 47.3% | 8403 | 47.3% |
Body mass index | 26.6 (SD = 4.4) | 26.5 (SD = 4.4) | ||
Waist-hip ratio | 0.87 (SD = 0.08) | 0.86 (SD = 0.08) | ||
Systolic blood pressure | 136.9 (SD = 17.9) | 136.9 (SD = 17.9) | ||
Diastolic blood pressure | 78.7 (SD = 10.0) | 78.6 (SD = 10.0) | ||
Alcohol drinks per monthd | 29.9 (SD = 32.9) | 29.8 (SD = 32.8) | ||
Years since quitting smokinge | 23.7 (SD = 14.4) | 23.9 (SD = 14.3) | ||
MRI covariatesf | ||||
Total gray matter volume (mm3) | 617000 (SD = 55621.9) | |||
Total white matter volume (mm3) | 548900 (SD = 61857.2) | |||
White matter hyperintensity volumeg (mm3) | 4357 (SD = 5573.8) | |||
