Table 3.
Included studies examining the association between cardiovascular risk/disease and the oral microbiome
| Author, year | Oral sample site(s) | Aim | Population studied | % Smokers | Sequencing | Region if 16S | Citation |
|---|---|---|---|---|---|---|---|
| Boaden, 2017 | Saliva, buccal mucosa, tongue, gingiva and hard palate | Describe the bacterial profile of the oral flora during the first two weeks following a stroke, examining changes in the condition of the oral cavity and infections | Patients with stroke (n = 50) | 20% current, 30% prior-smokers | 16S | V1–V9 | [75] |
| Fåk et al., 2015 | Whole mouth swab | Elucidate whether the oral microbiota composition differed between patients with asymptomatic and symptomatic atherosclerosis | Asymptomatic atherosclerosis (n = 35), symptomatic atherosclerosis (n = 27), control (n = 30), total (n = 92) | Current smokers: 9% asymptomatic atherosclerosis, 23% symptomatic atherosclerosis, 21% control | 16S | V1–V2 | [70] |
| Gordon et al., 2019 | Subgingival plaque | Characterize and compare the oral microbiome between four study groups based on BP status in postmenopausal women | Normal BP (n = 179), stage I hypertension (n = 106), Stage II hypertension (n = 42), patients on hypertension medications, irregardless of BP (n = 119), total (n = 446) | Current 4.5%, former 39.7% normal BP; current 2.8%, former 47.2% stage I; current 2.4%, former 40.5% Stage II, current 2.5%, former 45.4% patients on hypertension medications | 16S | V3–V4 | [69] |
| Leskelä et al., 2020 | Saliva | Investigate associations of specific oral bacteria and LPS neutralizing capacity in a case–control study of ischemic stroke | Controls (n = 100), Patients with stroke (n = 98), total (n = 198) | Current smokers: 12% controls, 28% patients with stroke | Targeted qPCR sequencing | N/A | [63] |
| Liljestrand et al., 2018 | Subgingival plaque | Study the association between periodontal pathogen burden, saliva and serum LPS activity and how periodontitis and coronary artery disease interrelate with them | Control (n = 123), stable CAD (n = 184), ACS (n = 169), ACS-like, no CAD (n = 29); total (n = 505) | Ever smokers: 46.3% control, stable CAD, ACS, ACS-like, no CAD; 52.9% total | DNA hybridization | N/A | [64] |
| Kannosh et al., 2018 | Subgingival plaque | Assess temporal changes in the frequency of periodontal bacteria in the subgingival plaque and in atherosclerotic blood vessels of patients with atherosclerosis | Patients with atherosclerosis (n = 100) | Smokers: 55% of total sample | Targeted 16S sequencing | N/A | [67] |
| Koren et al., 2011 | Oral cavity swab | Aimed to address: Is there a core atherosclerotic plaque microbiota? Are bacteria present in the plaque also detectable in the oral cavities or guts of the same individuals? Is an altered oral or fecal microbiota associated with atherosclerosis? | Controls (n = 15), patients with atherosclerosis (n = 15); total (n = 30) | Current smoker: 0%, controls, 40% patients with atherosclerosis | 16S | V1–V2 | [74] |
| Mahalakshmi et al., 2017 | Subgingival plaque | Determine the incidence of anaerobic periodontopathic bacterial co-occurrences in periodontitis and atherosclerosis | Control patients without periodontitis or systemic disease (n = 100), patients with atherosclerosis (n = 65); patients with periodontitis but no systemic disease (n = 59); total (n = 224) | Current or past smokers were excluded from the study | Targeted 16S sequencing | N/A | [71] |
| Nikolaeva et al., 2019 | Subgingival plaque | Characterize composition of subgingival biofilm with periodontopathogenic bacteria species and endothelium-dependent vasodilation in patients with chest pain and concomitant periodontitis | Patients with angina pectoris (n = 15); patients with acute myocardial infarction (n = 15); Patients with chest pain but no coronary artery disease (n = 15); total (n = 45) | Current smokers: 80% patients with angina pectoris; 60% patients with acute myocardial infarction; 47% patients with chest pain but no coronary artery disease | Targeted 16S sequencing | N/A | [72] |
| Perry et al., 2020 | Saliva | Establish how oral bacteria are related to cough sensitivity and pneumonia in a clinical stroke population | Patients with atherosclerosis (n = 100) | Not reported | Targeted qPCR | N/A | [76] |
| Serra e Silva Filho et al., 2014) | Subgingival plaque | Assess microbial diversity of the subgingival environment and atheroma plaques of patients with periodontitis and obstructive coronary artery atherosclerosis | Patients with periodontitis and atherosclerosis (n = 18) | Smokers: 55.6% of total sample | 16S | V1–V9 (27f/ 1492r primers) | [68] |
| Su et al., 2019 | Tongue dorsum | Study the association between oral bacteria on the tongue dorsum and factors associated with oral health and systemic disease in middle-aged and elderly patients | Total sample (n = 70) | Smokers: 11% of total sample | Targeted PCR sequencing | N/A | [73] |
| Ziebolz, Jahn, et al., 2018 | Subgingival plaque | Detect periodontal pathogens DNA in atrial and myocardial tissue, and to investigate periodontal status and their connection to cardiac tissue inflammation | Patients undergoing surgery for aortic valve stenosis (n = 30) | Smoking history was present in only 8 patients: average of 27.2 ± 21.8 pack/years in that subset | Targeted PCR sequencing | N/A | [66] |
| Ziebolz, Rost, et al., 2018 | Subgingival plaque | Detect correlations of microbiological DNA, inflammatory proteins, and infection parameters in patients with periodontal disease and valvular heart disease | Patients undergoing surgery for aortic valve stenosis (n = 10) | Smokers: 30% of total sample | Targeted PCR sequencing | N/A | [65] |
16S 16S ribosomal ribonucleic acid sequencing, ACS Acute Coronary Syndrome, BP blood pressure, CAD Coronary Artery Disease, DNA deoxyribonucleic acid, LPS lipopolysaccharide, PCR polymerase chain reaction, qPCR quantitative polymerase chain reaction, V variable region of the 16S ribosomal ribonucleic acid gene