Periodontitis is associated with an increased likelihood of hypertension, according to researchers at the University College London Eastman Dental Institute, who also found a reduction in blood pressure levels after periodontal therapy.
Previous studies have suggested a link between periodontitis and hypertension, but little has been known about the direction of the association. The UCL researchers aimed to ascertain whether patients with periodontitis were more likely to be diagnosed with hypertension than individuals without it. The systematic review also set out to investigate the effect of periodontal therapy on systolic blood pressure (SBP) and diastolic blood pressure (DPB).
“Periodontitis and hypertension affect millions of people worldwide. Both conditions have been independently linked to the incidence of cardiovascular events, leading to major health problems and significant impact on health costs. Additionally, hypertension and periodontitis share risk factors such as diabetes, poor diet, and smoking,” said lead author Eva Munoz Aguilera, a specialist in training periodontology at the institute.
“From a biological point of view, this association is possible since the microorganisms causing inflammation in gum disease can create local as well as systemic inflammation, leading to damage in the blood vessels,” she said. “We were interested in looking at the possibility of a more causal association between gum disease and blood pressure.”
Hypertension treatment, along with medication and lifestyle changes, has been associated with a decreased risk of heart and blood vessel complications and improved general health. Similarly, the treatment of gum disease via better oral hygiene and interventions such as nonsurgical and surgical periodontal treatment by an oral health professional leads to better oral health, with existing studies also pointing to the reduction of systemic inflammation, including a decrease in the stiffness of blood vessels.
“If it is proven that there is a link between periodontal disease and hypertension, and that it is a causal one, this would give us an opportunity to act in the diagnosis, prevention, and treatment of gum disease in order to contribute, in turn, to the prevention and treatment of hypertension, avoiding the devastating complications caused by raised blood pressure,” said Munoz Aguilera.
The systematic review included observational and interventional studies that were published before October 2017, with a comprehensive search of MEDLINE, EMBASE, CENTRAL, LILACS, and Web of Science for observational and interventional studies. Two authors independently reviewed, selected, and extracted data from the search and assessed risk of bias.
“The primary outcome was adjusted odds ratio for hypertension in patients with periodontitis (moderate and severe groups). The secondary outcome included blood pressure changes after periodontal therapy. We also looked into studies beyond periodontology-hypertension, extending our search to papers on heart disease, metabolic syndrome, and other chronic and systemic conditions linked to gum disease, retrieving blood pressure data of great value,” Munoz Aguilera said.
“What is new in our study is that we were looking at only one direction for the association: gum disease as a potential risk factor for hypertension. We excluded studies where hypertension was the exposure/independent variable,” she said.
Sixty-two studies met the inclusion criteria, with 21 considered for meta-analysis. The diagnosis of moderate to severe periodontitis was associated with 30% to 50% increased odds for high blood pressure. When severe periodontitis was evaluated, an increased estimate was calculated. In cohort studies examining the association, periodontitis predicted the occurrence of hypertension. Bias assessment revealed a low to moderate risk for all studies.
“When we looked into studies reporting the effects of gum therapy on measures of blood pressure, we saw a trend toward a decrease in blood pressure after periodontal treatment. Two out of the three interventional studies included in the review confirmed a reduction in blood pressure following periodontal therapy, ranging from an average of SBP = 1 to 12 mmHg and of DBP = 0 to 10 mmHg,” said Munoz Aguilera.
“This reduction points pretty much towards gum disease treatment reducing systemic inflammation. According to the results, we estimate that the treatment of gum disease in patients with raised blood pressure could be in the range or even higher of what is expected with a blood pressure drug, so this is quite significant. Nevertheless, these are early days,” Munoz Aguilera said.
“We need more research, such as longitudinal studies and randomized controlled trials with blood pressure as the primary outcome, to confirm this effect. Because of the sample size required to conduct further research on this topic, these studies will be costly. We hope to join forces with other health professionals in order to continue our research,” she said.
“The implications of our findings are that we should raise awareness among health professionals, patients, and policy makers that there is an association between gum disease and hypertension. Oral health advice should be given to all patients with hypertension as well as with other conditions associated with periodontitis, such as diabetes, pregnancy, etc,” Munoz Aguilera said.
“On the other hand, patients with periodontitis should be informed that there is a higher risk of developing hypertension and given advice on lifestyle changes. So far, we know that prevention and treatment of periodontitis provides better oral, systemic health, and improvement of the quality of life. Additionally, its treatment may help prevent/improve hypertension,” she said.
Munoz Aguilera presented her study, “Periodontitis and Its Treatment Are Associated with Hypertension: A Systematic Review and Meta-Analysis,” at the European Federation of Periodontology’s EuroPerio9 conference, June 20 to June 23 in Amsterdam.