3.1 Literature search and study characteristics
A total of 6706 articles were identified by search strategy. Seven
additional articles were found in reference lists of retrieved studies.
After removing the duplications and uncorrelated articles which were
checked by screening titles and abstracts, 264 articles were included.
We excluded 250 articles because: reviews (n=11); full texts were not
available (n=30); the association of interest was not evaluated (n=71);OR , RR or HR and corresponding 95% CI were
not available (n=138). Ultimately, 14 articles10-16,
24-27, 31, 38, 39 which fulfilled the inclusion criteria were included
in the meta-analysis (Figure 1).
Of the 17 studies about ischemic heart disease, there are 9 cohort
studies, 3 cross-sectional studies, and 5 case-control studies. Twelve
studies investigated the relationship between hysterectomy with ovarian
preservation and ischemic heart disease, 4 studies researched the
relationship between hysterectomy with oophorectomy and ischemic heart
disease. The relationships between surgery before 50 years old or
surgery after 50 years old and risk of ischemic heart disease were
investigated in 8 studies and 6 studies respectively.
Furthermore, 6 studies explored the relationship between hysterectomy
and CVD. And 5 studies for association with ovarian preservation and
CVD. Nine studies evaluated the relation between hysterectomy with
oophorectomy and CVD. Six studies assessing the relationship between
hysterectomy and hypertension were found. Four studies and three studies
were respectively used to evaluate the association between hysterectomy
with ovarian preservation and hypertension, and the relationship between
hysterectomy with oophorectomy and hypertension. There are 5 studies
included to assess the relation of hysterectomy and heart failure, 3
studies for arrhythmia and 8 studies for stroke. More details about the
included studies were shown in Table S1.