If the balance of oral bacterial diversity (also referred to as mouth flora) changes and specific bacteria gain the upper hand, this may impact on high blood pressure and increase the risk of cardiovascular disease. We described similar findings on this website in the past (cf. http://www.gesunde-bakterien.de/en/periodontitis-puts-heart-and-teeth-at-risk/). In a current study, scientists in the United States now report tangible evidence for this causal link.

During the study, the connection between oral bacteria and blood pressure was examined in more than 1,200 women with a mean age of 63 years (i.e. post-menopausal). Over an average period of ten years, they collected plaque samples, from which the researchers were able to identify 245 strains of bacteria. The specialist journal Zahnarzt Wirtschaft Praxis (ZWP) writes that almost a third of women who did not have high blood pressure at the beginning of the study had been diagnosed with hypertension by its completion. Analysis of the microbiome showed that ten bacterial strains were associated with a 10 to 16 percent higher risk of developing high blood pressure. Five other kinds of bacteria were associated with a 9 to 18 percent lower hypertension risk. This would suggest it may be possible to offset the risk by boosting the number of bacteria which have a positive effect.

“Since periodontal disease and hypertension are especially prevalent in older adults, there may be an opportunity to enhance hypertension prevention through increased, targeted oral care ” ZWP quotes Michael J. LaMonte of the University at Buffalo’s team of researchers. The findings are particularly relevant for postmenopausal women, “since the prevalence of high blood pressure is higher among older women than older men”. A randomized trial with randomly selected, female and male participants would be necessary to confirm which specific bacteria were causal agents in increasing — or decreasing — the risk of developing hypertension over time. This is still pending.
Sources:

https://www.medicalnewstoday.com/articles/do-oral-bacteria-play-a-role-in-hypertension#Link-between-bacteria-and-hypertension

https://www.ahajournals.org/doi/10.1161/JAHA.121.021930

https://www.zwp-online.info/zwpnews/dental-news/wissenschaft-und-forschung/orale-bakterien-stehen-in-zusammenhang-mit-bluthochdruck