Postmenopausal hypertensive women at risk of breast cancer
Hypertension is associated with an increased risk of breast cancer, particularly among postmenopausal women, a new meta-analysis finds.
PubMed, the Cochrane library and Embase were accessed for studies that looked at hypertension as the exposure and breast cancer as the outcome. Those that were cohort, case-controlled or nested case-control studies were included.
The methodological quality of studies were assessed using the Newcastle-Ottawa Quality Assessment Scale.
After applying inclusion and exclusion criteria, 30 observational studies were included. Overall, the evidence suggests an association between hypertension and a 15-percent increase in breast cancer risk (combined relative risk [RR], 1.15; 95 percent CI, 1.08 to 1.22).
In terms of quality, there was a significant heterogeneity across all included studies (p<0.001). There was no evidence of publication bias (p=0.26), and none of the studies affected the combined data used in the meta-analysis.
Subgroup analysis showed that, in prospective studies (combined RR, 1.07; 1.01 to 1.14, p=0.01) and retrospective studies (combined RR, 1.29; 1.14 to 1.47; p<0.001), hypertension was significantly associated with breast cancer.
Interestingly, Asian participants did not show a significant association between hypertension and breast cancer (combined RR, 1.07; 0.94 to 1.22; p=0.23).
Finally, postmenopausal hypertensive women (pooled RR, 1.20; 1.09 to 1.31; p=0.001),but not premenopausal hypertensive women (pooled RR, 0.97; 0.84 to 1.12; p=0.19), showed a significant association.
Health workers can use this information to increase screening for breast cancer in postmenopausal women with hypertension, the investigators recommend.