26 Phase Coherence Between Cardiovascular Oscillations in Malaria …
403
that endothelial reactivity is affected too. Erythrocytes are an important factor determining the hemorheological properties of blood, its corresponding shear-thinning
and increased shear stress at walls [46]. We therefore hypothesise that the oscillatory
properties and their degree of coherence between different parts of the system will
be altered in malaria. Blood flow takes place in a thermodynamically open system,
and therefore the oscillations are time-varying. Time series analysis methods for
non-autonomous dynamics [8, 9] must therefore be employed.
26.2 Materials and Methods
Here we summarise salient features of the measurements and data analysis, which
are described in fuller detail by Abdulhameed [1]. The anthropomorphic data for the
subjects used in the study are listed in Table 26.1.
Table 26.1 Anthropometric data for the subjects, presenting their: ages; body mass index (BMI);
skin temperature (ST); core temperature (CT); instantaneous heart rate (IHR); instantaneous respiration rate (IRR); systolic blood pressure (SBP); diastolic blood pressure (DBP); and blood packed
cell volume (PCV). Median values and their ranges (25th and 75th percentiles) are shown, with
significant differences ( p < 0.05) highlighted in grey. p1, p2 and p3 are values obtained from the
sign rank test for FM–NFM, FM–NM and NFM–NM comparisons respectively
FM
NFM
NM
p1
p2
p3
(n = 37)
(n = 10)
(n = 51)
Age (years)
20(18–25)
23(20–27)
22(20–24)
0.08
0.169
0.382
BMI (kg/m 2 ) 19.8
20
21.1
0.53
0.058
0.6
ST ( o C)
38.2
35.5
35.9
2 × 10 −6 10 −9
0.514
CT ( o C)
38.9
37.80
36.15
10 −9
2 × 10 −5 7 × 10 −5
IHR (Hz)
1.72
1.36
1.14
0.002
0.00009
0.00009
IRR (Hz)
0.44
0.35
0.33
0.02
3 × 10 −7 0.325
SBP (mm Hg) 112
113
124
0.79
0.039
0.07
DBP (mm Hg) 63
73
77
0.03
0.00014 0.45
PCV (%)
42
44
44
1
0.02
0.17
18.1–21.8
19.5–21.5
19.1–22
37.6–38.9
35.1–36.4
35.7–36.1
38.2–39.2
37.6–38.0
35.9–36.5
1.53–1.85
1.28–1.55
1.02–1.26
0.37–0.49
0.32–0.45
0.30–0.37
106–125
106–118
110–128
57–70
68–80
69–82
40–43
41–45
42–47
403
that endothelial reactivity is affected too. Erythrocytes are an important factor determining the hemorheological properties of blood, its corresponding shear-thinning
and increased shear stress at walls [46]. We therefore hypothesise that the oscillatory
properties and their degree of coherence between different parts of the system will
be altered in malaria. Blood flow takes place in a thermodynamically open system,
and therefore the oscillations are time-varying. Time series analysis methods for
non-autonomous dynamics [8, 9] must therefore be employed.
26.2 Materials and Methods
Here we summarise salient features of the measurements and data analysis, which
are described in fuller detail by Abdulhameed [1]. The anthropomorphic data for the
subjects used in the study are listed in Table 26.1.
Table 26.1 Anthropometric data for the subjects, presenting their: ages; body mass index (BMI);
skin temperature (ST); core temperature (CT); instantaneous heart rate (IHR); instantaneous respiration rate (IRR); systolic blood pressure (SBP); diastolic blood pressure (DBP); and blood packed
cell volume (PCV). Median values and their ranges (25th and 75th percentiles) are shown, with
significant differences ( p < 0.05) highlighted in grey. p1, p2 and p3 are values obtained from the
sign rank test for FM–NFM, FM–NM and NFM–NM comparisons respectively
FM
NFM
NM
p1
p2
p3
(n = 37)
(n = 10)
(n = 51)
Age (years)
20(18–25)
23(20–27)
22(20–24)
0.08
0.169
0.382
BMI (kg/m 2 ) 19.8
20
21.1
0.53
0.058
0.6
ST ( o C)
38.2
35.5
35.9
2 × 10 −6 10 −9
0.514
CT ( o C)
38.9
37.80
36.15
10 −9
2 × 10 −5 7 × 10 −5
IHR (Hz)
1.72
1.36
1.14
0.002
0.00009
0.00009
IRR (Hz)
0.44
0.35
0.33
0.02
3 × 10 −7 0.325
SBP (mm Hg) 112
113
124
0.79
0.039
0.07
DBP (mm Hg) 63
73
77
0.03
0.00014 0.45
PCV (%)
42
44
44
1
0.02
0.17
18.1–21.8
19.5–21.5
19.1–22
37.6–38.9
35.1–36.4
35.7–36.1
38.2–39.2
37.6–38.0
35.9–36.5
1.53–1.85
1.28–1.55
1.02–1.26
0.37–0.49
0.32–0.45
0.30–0.37
106–125
106–118
110–128
57–70
68–80
69–82
40–43
41–45
42–47