Results
The women’s baseline characteristics and echocardiographic findings
stratified by parity status were listed in Table1. A total of 600 women
(mean age 45.1± 6.8) were included. The baseline characteristics of
cases were similar in terms of age, hypertension, diabetes mellitus,
hyperlipidemia, current smoking status, body mass index and body surface
area. In echocardiographic analysis, RV length, mid and basal diameters,
RV systolic and diastolic areas, RV wall thickness, RA area and volume,
estimated PAP were significantly higher in parous women. On the other
hand, parameters using for evaluation of RV function such as TAPSE, FAC,
S’ velocity were significantly lower in parous women. The decrease in
these parameters, however, has not reached under the lower reference
limit according to the guideline. Grand multiparous women had the
highest values which were higher in parous women and the lowest values
which were lower in parous women. LV ejection fraction and LV
end-diastolic dimension were similar between the groups. Figure 1
demonstrates the distribution of RV basal diameter stratified by parity
category. In nulliparous group, 8 women (4%) had RV dilation and 6
women (3%) had RV hypertrophy. In women with a parity number of 1 to 4,
11 women (5.5 %) had RV dilation and 19 women (9.5%) had RV
hypertrophy. In grand multiparous group, 42 women (22.4 %) had RV
dilation and 33 women (16.4 %) had RV hypertrophy.
Two different hierarchical logistic regression analyses were performed
and demonstrated in Table 2 and 3. In the first analysis (Table 2), the
univariate predictors of RV dilation were age, body mass index, body
surfacearea, hyperlipidemia, smokingand giving a birth (being parous vs
nulliparous). By multivariate hierarchical logistic regression analysis,
the 4 independent factors that increased the risk of RV dilation were
age (OR: 1.16 CI: 1.10 – 1.20), body mass index (OR: 1.05, CI: 1.02 to
1.08), smoking (OR: 1.87, CI: 1.28 to 4.02), and giving a birth (OR:
3.94 CI: 1.82 – 8.81).
In the second analysis (Table 3) RV dilation and hypertrophy had the
highest rates at parity category of > 4 parity and that had
6.9 and 6.3-times higher than nulliparous category respectively, which
had the lowest rates and used as the reference group. This relationship
persisted even after adjustment for several confounders; RV dilation and
hypertrophy had the highest rates at parity category of > 4
and that had 5.2 and 5.4-times higher than nulliparous category
respectively. Compared with the reference group, the women with the
parity category of 1< to 4 parity had 3.4 times higher RV
hypertrophy and this relationship persisted even after adjustment for
several confounders. However, compared with the reference group, the
women with the parity category of 1 to 4 parity had higher rates of RV
dilation, it did not reach to statistical significance.