Clinical characteristics of the LDLR-M and 50 LDLR-WT patients are presented in Table 1.
We found no statistical difference in body mass index (BMI),
history of diabetes and hypertension,
or triglycerides (TG) levels between the LDLR-M and LDLR-WT groups (Table 1).
The LDLR-M group,
however had higher maximum total cholesterol (TCmax) and LDL-C max levels,
and lower on-treatment high-density lipoprotein cholesterol (HDL-C) levels.
The results of AVCS calculated using volumetric methods including AVCS distribution across calcium score ranges are presented in Table 2.
We found AVCS to be significantly higher in the LDLR-M group in comparison with the LDLR-WT group.
The Yates' chi-squared test for independence revealed that LDLR mutation and AVCS were significantly dependable (Chi^2=6.106,
p=0.013).
In order to determine the best set of variables that explains dichotomous variable AVCS multivariate regression analysis was applied.
For this analysis,
we selected patients with high AVCS results if the value was in the top 20% of the calcium score distribution.
Finally,
the presented model was statistically significant (Chi^2=35.63,
p<0.001) and took into account those independent variables that were strongly correlated with AVCS but not with each other (Table 3).
A positive value of LDLR mutation was a strong predictor of the high AVCS (OR 7.83,
95% CI 2.08-29.50,
p=0.002).
From the traditional risk factors,
age (odds ratio 1.12,
95% CI 1.05-1.18,
p<0.001) and SBP (OR 1.04,
95% CI 1.00-1.07,
p=0.045) were significant for high AVCS.
Table 1.
Clinical characteristics of LDLR-M and NFH groups
|
LDLR-M (N=72)
|
NFH (N=50)
|
p
|
Age (years)
|
49.1 ± 11.9
|
51.5 ± 9.9
|
ns
|
Gender
|
29 M,
43 F
|
23M,
27 F
|
ns
|
BMI (kg/m2)
|
26.5 ± 4.2
|
26.9 ± 4.1
|
ns
|
TC max (mmol/L)
|
9.6± 2
|
8.1 ± 1.5
|
<0.001
|
LDL max§ (mmol/L)
|
7.3±1.7
|
5.9 ± 1.1
|
<0.001
|
HDL max§ (mmol/L)
|
1.5±0.4
|
1.5 ± 0.3
|
ns
|
TG max§ (mmol/L)
|
1.6±0.9
|
1.6 ± 0.8
|
ns
|
TC (mmol/L)
|
7.4±2.3
|
7.4 ± 1.5
|
ns
|
LDL (mmol/L)
|
5.4±2.1
|
5.1 ± 1.3
|
ns
|
HDL (mmol/L)
|
1.4±0.3
|
1.5 ± 0.3
|
=0.04
|
TG (mmol/L)
|
1.4±0.7
|
1.5 ± 0.7
|
ns
|
SBP (mmHg)
|
131.9 ± 15.5
|
133.4 ± 14.5
|
ns
|
DBP (mmHg)
|
83 ± 11.1
|
82.7 ± 8.7
|
ns
|
Diabetes† (n)
|
1 (1.4%)
|
5 (10%)
|
ns
|
Smoking¶ (n)
|
24 (33.3%)
|
21 (42%)
|
ns
|
Statin treatment on 1st visit (n)
|
38 (52.8)
|
20 (40%)
|
ns
|
Abbreviations: LDLR-M – patients with familial hypercholesterolemia and LDLR mutation,
NFH – nonfamilial hypercholesterolemia,
NS – not significant,
BMI - body mass index,
TC – total cholesterol,
LDL- low‐density lipoprotein,
HDL - high‐density lipoprotein cholesterol,
TG – triglycerides, max – maximum levels without pharmacotherapy,
SBP – systolic blood pressure.
DBP – diastolic blood pressure,
§ data not available in three patients,
†treatment with insulin or oral anti-diabetic medicine,¶smoking - ever,
> 1 pack-year
Table 2.
Volumetric calcium score of aortic valve in LDLR-M and NFH groups
|
|
LDLR-M
|
NFH
|
p value
|
|
|
|
|
|
AVCS (mm3)
|
median
|
0
|
0
|
P=0.03
|
|
mean ± SD
|
13.8 ± 37.9
|
0.94 ± 3.1
|
|
|
Q1
|
0
|
0
|
|
|
Q3
|
9.5
|
0
|
|
|
max
|
196
|
19
|
|
|
min
|
0
|
0
|
|
Abbreviations: LDLR-M – patients with familial hypercholesterolemia and LDLR mutation,
NFH – nonfamilial hypercholesterolemia,
AVCS - aortic valve calcium score,
NS – not significant,
SD – standard deviation Q1 – first quartile 1,
Q3 – third quartile
Table 3.
Multivariate logistic regression analysis for identification of patients with high AVCS (N=122,
high AVCS N=24).
Covariate
|
Chi2=35,63 p<0.001
|
|
|
|
|
|
19.78
|
13.98
|
9.45
|
4.01
|
|
|
1.12
|
7.83
|
1.04
|
|
|
1.05
|
2.08
|
1.00
|
|
|
1.18
|
29.50
|
1.07
|
|
<0.001
|
<0.001
|
0.002
|
0.045
|
Abbreviations: AVCS – aortic valve calcium score