Table 1.

Demographic and experimental data of young and elderly subjects

	Young (<46 years old)	Elderly (≥46 years old)
N	69	69
Sex (F)	48	42
Age, years, mean ± SD (range)	28 ± 7.3 (17–45)	67.9 ± 8.5 (47–86)
Medication (N)		37
Anticonvulsant		0
Antidepressant		0
Antihypertensive		32
Beta-blocker		12
ASA		11
NSAID		3
Antacids		4
Steroids		3
Statins		11
Thyroxine		8
Tamsulosin (α1a-selective alpha blocker)		4
Others (Mictonorm, Norfloxacin, Phenprocoumon, Quinine Sulphate)		4
Stimulation intensity (mean ± SEM)	2.28 ± 0.81**	3.89 ± 0.25
Single-pulse A1 (μV; mean ± SEM)	4.62 ± 0.35	4.55 ± 0.39
Paired-pulse A1 (μV; mean ± SEM)	4.02 ± 0.27	4.32 ± 0.38
Paired-pulse A2 (μV; mean ± SEM)	1.77 ± 0.14**	2.72 ± 0.33
Ratio A2/A1 (mean ± SEM)	0.45 ± 0.03***	0.64 ± 0.05
Two-point discrimination thresholds (mm; mean ± SEM)		3.33 ± 0.14
For elderly subjects with ratios <1 (N = 13)		3.07 ± 0.18
For elderly subjects with ratios >1 (N = 13)		3.58 ± 0.18

F, Female; ASA, acetylsalicylic acid; NSAID, non-steroidal anti-inflammatory drugs.

** p < 0.01;

*** p < 0.001.