Carriage of periodontal pathogens in pancreatic cancer cases and controls in the combined CPS II and PLCO cohort
| Cases (n=361) | Controls (n=371) | |||||
|---|---|---|---|---|---|---|
| Periodontal pathogens | N (%) | N (%) | OR* | 95% CI* | p Value* | p Trend† |
| P. Gingivalis | ||||||
| Non-carriers | 233 (64.5) | 275 (74.1) | 1.00 | – | – | |
| Any carriers | 128 (35.5) | 96 (25.9) | 1.60 | 1.15 to 2.22 | 0.0048 | |
| Non-carriers | 233 (64.6) | 275 (74.2) | 1.00 | – | – | 0.0047 |
| Low carriers‡ | 59 (16.3) | 48 (12.9) | 1.47 | 0.96 to 2.26 | 0.078 | |
| High carriers‡ | 69 (19.1) | 48 (12.9) | 1.73 | 1.14 to 2.63 | 0.011 | |
| A. actinomycetemcomitans§ | ||||||
| Non-carriers | 330 (91.4) | 356 (96.0) | 1.00 | – | – | |
| Any carriers | 31 (8.6) | 15 (4.0) | 2.20 | 1.16 to 4.18 | 0.016 | |
| T. forsythia | ||||||
| Non-carriers | 191 (52.9) | 210 (56.6) | 1.00 | – | – | |
| Any carriers | 170 (47.1) | 161 (43.4) | 1.16 | 0.86 to 1.55 | 0.34 | |
| P. intermedia | ||||||
| Non-carriers | 279 (77.3) | 301 (81.1) | 1.00 | – | – | |
| Any carriers | 82 (22.7) | 70 (18.9) | 1.30 | 0.89 to 1.88 | 0.17 | |
*ORs, 95% CIs, and p values were calculated from logistic regression after controlling for the random effect of cohorts as well as other covariates (age, race, sex, BMI, smoking status, alcohol consumption status and history of diabetes).
†p Trend was calculated by assigning values 0–2 to the non-carriers, low carriers and high carriers of P. gingivalis, respectively, and treating this as a continuous variable in the logistic regression model, after controlling for the random effect of cohorts as well as other covariates (age, race, sex, BMI, smoking status, alcohol consumption status and history of diabetes).
‡Cut-off point was based on the median relative abundance of P. gingivalis carriers in the control group of each cohort (the median relative abundance of P. gingivalis among controls is 0.12% in CPS II cohort, and 0.056% in PLCO cohort).
§Dose–response could not be evaluated due to low overall carriage prevalence.
A. actinomycetemcomitans, aggregatibacter actinomycetemcomitans; BMI, body mass index; CPS, Cancer Prevention Study; P. gingivalis, porphyromonas gingivalis; P. intermedia, prevotella intermedia; PLCO, prostate, lung, colorectal and ovarian cancer; T. forsythia, tannerella forsythia.