Cardiovascular Journal of Africa: Vol 29 No 5 (September/October 2018)

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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 29, No 5, September/October 2018 AFRICA 285
normoalbuminuric diabetics (p = 0.02). WC, SBP and PR showed
a significant stepwise increase from control to microalbuminuric
group (p < 0.001, p = 0.03, p = 0.03, respectively). Weight, BMI,
WHR, DBP and PP were comparable among the three groups.
Renal function, as assessed by estimated glomerular filtration
rate (eGFR) using the Cockcroft Gault formula, was reasonably
preserved among the three groups. It was highest in the control
group but not statistically significantly different.
The mean values of all lipid components were normal
and comparable, except for the low-density lipoprotein (LDL)
cholesterol level and atherogenic ratio, which showed a significant
stepwise increase from control to microalbuminric group (p =
0.0008 and p = 0.01, respectively). FBS was also significantly
higher in the diabetic groups compared to the controls (p = 0.001).
Table 2 shows the echocardiographic parameters of LV function
among the three groups. Mean values of EF and FS were normal
in the three groups, but FS showed a significant stepwise decrease
from control to microalbuminuric group (p = 0.0002).
Doppler echocardiographic parameters showed some degree
of LV diastolic dysfunction, which was more pronounced in the
diabetic groups. A velocity (p = 0.0034), IVRT (p = 0.0001) and
PASP (p = 0.02) showed a significant stepwise increase from
control to microalbuminuric group, with a reverse trend for E
velocity (p < 0.001) and E/A ratio (p < 0.001).
Fig. 1 shows the prevalence and pattern of LVDD
among the three groups. The prevalence of LVDD showed a
stepwise increase from 16.9% in the control to 78.9% in the
microalbuminuric group. The most common grade of DD was
grade 1, which occurred in 70.4 and 55.5% of microalbuminuric
and normoalbuminuric groups, respectively, compared to 16.9%
in the controls. Grade 1 was the only type of DD found in the
control group; 3.2% of the normoalbuminuric group and 8.5%
of the microalbuminuric group had grade 2 pattern of DD. None
of the microalbuminuric group had grade 3 but 3.2% of the
normoalbuminuric group did. These observed differences were
statistically significantly different (χ 2 = 50.05, p < 0.01).
Table 3 shows clinical and biochemical parameters that
correlated significantly with indices of LV diastolic function
(E/A ratio and IVRT) among the normotensive diabetics. The
strongest correlate of E/A ratio in the model was age (p < 0.001).
Serum creatinine level (p = 0.009) and eGFR ( p = 0.009) also
correlated significantly with E/A, but the other parameters did
not.
Table 4 shows univariate and multivariate regression models
used to determine predictors of LVDD in the normotensive
diabetics. At the univariate level, age and MCA status were
significantly associated with the occurrence of LVDD. Those
with microalbuminuria had about a four-fold increased risk of
developing LVDD compared to those with normoalbuminuria
(95% CI: 1.99–6.82, p < 0.001). Also, for every one year increase
in age, the risk of developing DD increased by 11% (95% CI:
4–17%, p ≤ 0.001).
After adjusting for all the other factors in the multivariate
model, only age remained an independent predictor of DD. The
model shows that for every one year increase in age, there was
Table 1. Sociodemographic, anthropometric and laboratory data
(mean ± SD) variations among healthy controls, and normotensive
diabetics with normoalbuminuria or microalbuminuria
Characteristics
Controls
(n = 59)
Normo-
albuminuric
No = 63
Micro-
albuminuric
(n = 71) F-test p-value
Age (years) 47 ± 10.0 50 ± 7.5 51 ± 7.0 0.87 0.43
Gender (% male) 49 51 45 2.05 0.36
DMdur (years) 0 4.7 ± 2.8 6.1 ± 4.1 2.38 0.02
Weight (kg) 66 ± 11 68 ± 13 69 ± 12 1.00 0.37
Height (cm) 162 ± 8 162 ± 8 161 ± 9 0.62 0.54
BMI (kg/m2) 24.93 ± 4.4 26.4 ± 5.2 26.5 ± 3.8 2.14 0.12
BSA (m2) 1.71 ± 0.17 1.74 ± 0.18 1.75 ± 0.18 0.64 0.53
Waist (cm) 83 ± 10*† 89 ± 10 91 ± 10 11.19 < 0.001
WHR 0.89 ± 0.08 0.93 ± 0.07 0.93 ± 0.13 2.96 0.05
SBP (mmHg) 116 ± 11† 118 ± 9 120 ± 8 3.51 0.03
DBP (mmHg) 74 ± 8 74 ± 6 76 ± 6 2.62 0.08
PP (mmHg) 42 ± 9 42 ± 6 43 ± 7 1.42 0.25
PR (beats/min) 79 ± 12* 83 ± 10 83 ± 8 3.55 0.03
Creatinine (mg/dl) 0.9 ± 0.19 1.0 ± 0.31 1.01 ± 0.24 2.64 0.08
Urea (mmol/l) 2.6 ± 0.8*† 4.2 ± 1.7 4.0 ± 1.7 4.3 0.02
eGFR (ml/min) 102 ± 20 79 ± 31 86 ± 30 2.38 0.10
TC (mmol/l) 4.0 ± 0.6 4.6 ± 1.1 4.5 ± 1.2 1.17 0.32
TG (mmol/l) 0.9 ± 0.4 1.3 ± 0.8 1.1 ± 0.5 2.33 0.10
HDL-C (mmol/l) 1.73 ± 0.3 1.45 ± 0.5 1.37 ± 0.5 2.81 0.07
LDL-C (mmol/l) 1.74 ± 0.6† 2.38 ± 1 2.64 ± 0.8 5.14 0.008
AR 2.3 ± 0.4*† 3.5 ± 1.6 3.6 ± 1.0 4.67 0.01
FBS (mmol/l) 5.0 ± 0.5*† 8.1 ± 4 9.3 ± 4 3.72 0.001
F-test for ANOVA or student’s t-test.
*p < 0.05 compared to normoalbuminuria by ANOVA.
†p < 0.05 compared to microalbuminuria by ANOVA.
BMI: body mass index, BSA: body surface area, DMdur: duration of diabetes
mellitus, WHR: waist:hip ratio, SBP: systolic blood pressure, DBP: diastolic
blood pressure, PR: pulse rate, PP: pulse pressure, AR: atherogenic ratio, eGFR:
estimated glomerular filtration rate, TC: total cholesterol, TG: triglycerides,
HDL-C: high-density lipoprotein cholesterol, LDL-C: low-density lipoprotein
cholesterol, FBS: fasting blood sugar level.
Table 2. Comparison of echocardiographic parameters (mean ± SD) of
left ventricular systolic and diastolic function among healthy controls,
and normotensive diabetics with normoalbuminuria or microalbuminuria
Echo parameters
Control
(n = 59)
Normo-
albuminuric
(n = 63)
Micro-
albuminuric
(n = 71) F-test p-value
LVIDd (mm) 42 ± 4.4 † 40 ± 4.9 38 ± 4.3 7.84 0.0006
LVIDs (mm) 27 ± 3.2 26 ± 2.8 26 ± 3.2 0.81 0.45
EDV (ml) 82 ± 19† 76 ± 20 68 ± 16 8.13 0.0004
ESV (ml) 27 ± 8 26 ± 8 25 ± 7 0.82 0.44
Stroke volume (ml) 54 ± 20† 51 ± 19† 45 ± 17 9.28 0.0002
Cardiac output (l) 4.3 ± 0.9† 4.2 ± 1.1 † 3.6 ± 1.0 10.05 0.0002
Ejection fraction (%) 62 ± 7.3 63 ± 8 60 ± 6.2 1.99 0.14
FS (%) 36 ± 5.5 † 34 ± 6.1 † 31 ± 4.1 11.39 < 0.001
Mitral E velocity (m/s) 77 ± 21* † 65 ± 18 61 ± 12 20.65 < 0.001
Mitral A velocity (m/s) 67 ± 17† 69 ± 13 74 ± 13 5.9 0.0034
E/A ratio 1.2 ± 0.3† 1.0 ± 0.3 0.8 ± 0.2 31.51 < 0.001
IVRT (s) 79 ± 13† 84 ± 16 90 ± 18 9.65 0.0001
Deceleration time (s) 199 ± 29 192 ± 42 192 ± 33 0.03 0.9658
PVF S velocity (m/s) 56 ± 11† 47 ± 14 52 ± 11 4.57 0.0123
PVF D velocity (m/s) 49 ± 8* 42 ± 7 47 ± 11 5.11 0.0074
S/D ratio 1.2 ± 0.2 1.1 ± 0.2 1.1 ± 0.3 0.38 0.685
PVF Ar velocity (m/s) 31 ± 4.4 33 ± 4.0 34 ± 3.0 2.72 0.069
PASP (mmHg) 30 ± 8 30 ± 7† 33 ± 9 4.22 0.0165
LADs (mm) 35 ± 3.3 34 ± 3.5 † 36 ± 3.6 4.5 0.0125
*p < 0.05 compared to normoalbuminuria by ANOVA followed by Bonferroni
post hoc test.
† p < 0.05 compared to microalbuminuria by ANOVA followed by Bonferroni post
hoc test.
F-test for ANOVA.
PVF: pulmonary venous flow, LADs: left atrial end-systolic dimension, IVRT:
isovolumic relaxation time, E: transmitral early-to-late inflow velocity ratio, A:
transmitral late atrial velocity, PASP: pulmonary artery systolic pressure.