Table 1: Demographic features and caffeine consumption.

- Patients Controls Statistic (P)
- Mean/N SD/% Mean/N SD/%
Age 41 12 40 14 ns
Females 43 66 44 67 ns
Current smoker 7 11 2 3 ns
Daily caffeine intake (mg) 259 126 100 90 <0.001
Use of caffeine-containing medications 26 40 4 6 <0.001
Consumption of energy drinks 7 11 0 - 0.007
Harmful caffeine use 9 14 0 - <0.002
Hours of sleep 5.1 2.0 7.5 1.3 <0.001

ns = non statistically significant; SD = standard deviation.