Table 2.

Select characteristics of control subjects by mtDNA copy number (quintiles)a

MtDNA copy number quintiles
Q1Q2Q3Q4Q5
Characteristic≤94.6>94.6–≤113.3>113.3–≤132.8>132.8–≤158.0>158.0
mtDNA copy numberb, c83.2104.2123.6144.5186.2
Age, yc5858585858
Height, cmc174173174173173
Body Mass Index, kg/m226.426.526.126.426
Smoking historyc
 Cigarettes smoked per day20.518.819.318.818
 Years of smoking36.43735.935.535.1
 Pack-years of smoking38.234.93534.132.4
Medical history, %
 Diabetes mellitus3.86.85.63.12.5
 Pancreatitis2.3000.80.9
 Gallstones10.57.52.81.55.9
 Peptic ulcers20.31516.215.418.6
Primary education or less, %7975.98175.478
Living in city, %45.946.651.440.854.2
Daily dietary intakec
 Energy, kcal2,6102,7132,6592,6622,700
 Total fat, gd124121121122125
 Saturated fat, gd5351525354
 Carbohydrate, gd268266272269270
 Protein, gd9495959694
 Folated, μg333348342336344
 Alcohol, g15.820.216.516.313.8
Physical activity, %
 Occupational activity
  Sedentary10.516.59.218.512.7
  Moderate36.835.330.328.533.9
  Heavy7.57.26.65.66.1
  Not working45.941.451.443.142.4
 Leisure activity
  Sedentary37.639.127.541.534.8
  Light or moderate53.454.960.651.555.9
  Exercising to keep fit96126.99.3
Serum levels–baselinec
 AT, μg/L12.112.412.112.211.9
 BC, μg/L230214228233230
 Retinol, μg/L565602583607588
Serum–postinterventionc, e
 AT, μg/L18.117.717.618.418.2
 BC, μg/L2,9533,1673,6152,9613,043
 Retinol, μg/L588611585630597
Randomization group
 Alpha-Tocopherol (AT)33.819.630.323.919.5
 Beta-Carotene (BC)21.130.123.324.625.4
 AT and BC21.823.323.223.929.7
 Placebo23.327.123.227.725.4
  • aBased on total number of controls n = 656.

  • bUnits of measurement = number of copies of mtDNA per cell.

  • cMean values unless otherwise noted.

  • dAdjusted by total energy intake. Number of controls = 609.

  • eNumber of controls = 642; Postintervention serum measures limited to subjects in the intervention arm only.