The Characterization of Biological Rhythms in Mild Cognitive Impairment

Table 1

Nonparametrical characterization of the study group.

	Healthy	MCI	MD	MCI except MD
Wrist temperature
IS	0.49 ± 0.04	0.43 ± 0.04	0.41 ± 0.05	0.46 ± 0.07
IV	0.20 ± 0.02	0.20 ± 0.02	0.19 ± 0.03	0.22 ± 0.03
RA	0.25 ± 0.02	0.23 ± 0.02	0.22 ± 0.02	0.25 ± 0.05
M5	𝟎𝟒:𝟐𝟎±𝟎𝟎:𝟐𝟏^1a	𝟎𝟐:𝟓𝟐±𝟎𝟎:𝟐𝟏^2	𝟎𝟐:𝟓𝟑±𝟎𝟎:𝟐𝟐^b	06:26 ± 02:31
L10	𝟏𝟒:𝟑𝟓±𝟎𝟎:𝟐𝟕^1a	𝟏𝟑:𝟐𝟒±𝟎𝟎:𝟏𝟔^2	𝟏𝟑:𝟏𝟖±𝟎𝟎:𝟐𝟎^b	14:32 ± 00:50
CFI	0.55 ± 0.02	0.52 ± 0.02	0.51 ± 0.02	0.53 ± 0.04
Motor activity
IS	0.45 ± 0.02	0.46 ± 0.02	0.49 ± 0.02	0.41 ± 0.05
IV	0.77 ± 0.03	0.73 ± 0.03	0.73 ± 0.03	0.73 ± 0.05
RA	0.78 ± 0.02	0.80 ± 0.02	0.80 ± 0.03	0.81 ± 0.04
L5	03:48 ± 00:11	03:23 ± 00:13	03:10 ± 00:17	03:55 ± 00:25
M10	14:34 ± 00:17	14:08 ± 00:21	𝟏𝟑:𝟑𝟏±𝟎𝟎:𝟐𝟏^∗	𝟏𝟓:𝟐𝟗±𝟎𝟎:𝟒𝟔^∗
CFI	0.62 ± 0.02	0.63 ± 0.01	0.64 ± 0.02	0.62 ± 0.02
Body position
IS	0.50 ± 0.04	0.47 ± 0.05	0.49 ± 0.06	0.44 ± 0.07
IV	0.31 ± 0.02	0.33 ± 0.03	0.32 ± 0.03	0.34 ± 0.05
RA	0.47 ± 0.04	0.43 ± 0.04	0.45 ± 0.05	0.41 ± 0.06
L5	04:34 ± 00:29	02:53± 00:47	03:01 ± 00:57	03:46 ± 01:21
M10	14:30 ± 00:45	12:57 ± 00:57	12:50 ± 01:17	12:01 ± 01:37
CFI	0.61 ± 0.03	0.58 ± 0.03	0.59 ± 0.04	0.56 ± 0.04
TAP
IS	0.61 ± 0.03	0.57 ± 0.04	0.60 ± 0.04	0.53 ± 0.10
IV	0.26 ± 0.02	0.28 ± 0.02	0.28 ± 0.02	0.27 ± 0.04
RA	0.55 ± 0.03	0.49 ± 0.04	0.51 ± 0.04	0.48 ± 0.08
L5	𝟎𝟒:𝟏𝟖±𝟎𝟎:𝟏𝟒^1a	𝟎𝟐:𝟓𝟓±𝟎𝟎:𝟑𝟎^2	𝟎𝟑:𝟏𝟓±𝟎𝟎:𝟏𝟗^b	03:36 ± 00:27
M10	𝟏𝟒:𝟑𝟎±𝟎𝟎:𝟏𝟖^1a	𝟏𝟑:𝟐𝟖±𝟎𝟎:𝟐𝟑^2	13:30 ± 00:23	13:57 ± 00:54
CFI	0.68 ± 0.02	0.64 ± 0.03	0.65 ± 0.03	0.62 ± 0.06
Light exposure
IS	0.64 ± 0.03	0.68 ± 0.02	0.67 ± 0.02	0.70 ± 0.03
IV	0.26 ± 0.02	0.25 ± 0.01	0.27 ± 0.01	0.23 ± 0.02
RA	0.98 ± 0.01	0.97 ± 0.01	0.98 ± 0.01	0.96 ± 0.02
L5	04:17 ± 00:09	03:56 ± 00:13	03:43 ± 00:08	04:17 ± 00:20
M10	14:29 ± 00:15	14:18 ± 00:05	14:11 ± 00:05	14:29 ± 00:07
CFI	0.83 ± 0.01	0.84 ± 0.01	0.84 ± 0.01	0.85 ± 0.02

These indexes were calculated throughout the study for the healthy group (𝑛=19), the cognitively impaired group (MCI, 𝑛=21), the multidomain subgroup (MD, 𝑛=13), and MCI patients excluding the multidomain subgroup (MCI except MD, 𝑛=8).
Student’s 𝑡-tests were used to compare the healthy and MCI groups (different numbers, “1” and “2”, indicate statistically significant differences), the healthy and MD subgroups (different letters, “a” and “b”, indicate statistically significant differences), and the MD subgroup and the rest of the MCI patients (an asterisk marks statistically significant differences). In addition, significant differences are highlighted in bold.
All values are expressed as mean ± SEM.
IS stands for interdaily stability; IV for intradaily variability; RA for relative amplitude; M5 and M10 for the center of the consecutive period of 5 and 10 hours of maximum values, respectively; L10 and L5 indicate the consecutive 10- and 5-hour periods of minimum values, respectively; and CFI corresponds to the circadian function index.