Psoriasis linked to periodontal disease in new study

People with psoriasis may also be at an increased risk for periodontal disease. The findings of a new study linked the itchy, red skin condition to the health of teeth and gums.

Psoriasis is a chronic autoimmune skin disease that presents as thick, red, and sometimes scaly patches on various parts of the body, such as the elbow and scalp. Researchers from Germany believe gene expressions attributed to inflammation and bone resorption may underpin both psoriasis and periodontitis. They published their findings in the Journal of Investigative Dermatology (January 2, 2019).

"Genetic factors, pathophysiologic overlaps, and common risk factors may be common in both conditions," wrote the authors, led by Sirka Woeste, an assistant dentist at Kiel University Clinic of Conservative Dentistry and Periodontology in Kiel, Germany. "Gene polymorphisms ... are mentioned as risk factors for both psoriasis and periodontitis."

New prospective study

Few studies have evaluated the relationship between psoriasis and periodontitis, but previous ones have found a significant link may exist between the two conditions. Therefore, the researchers from Germany wanted to conduct a prospective study to serve as a springboard for further research.

"The data on oral health parameters for psoriasis patients are not yet consistent and exhaustive," the authors of the current study wrote. "To enlarge the data basis for periodontal and dental health in psoriasis patients, we aimed to get a comprehensive oral status of psoriasis patients in comparison to patients not having psoriasis in a prospective fashion."

The researchers began by enrolling 100 patients with psoriasis and 101 patients without psoriasis in their study. A dentist evaluated the oral health of all patients by performing bleeding on probing, community periodontal index (CPI), and decayed, missing, filled teeth assessments. The patients also filled out a questionnaire that included their age, smoking status, education level, and oral hygiene habits.

The researchers then performed two statistical analyses. In the first, they matched patients with psoriasis who had similar demographic and health factors to those without psoriasis. This matched analysis resulted in 53 pairs of patients with similar ages, oral healthcare habits, food intake, body mass indexes, and education levels.

The second statistical analysis, a logistic regression, included all 201 patients. From this analysis, the researchers were able to identify whether psoriasis may be an independent risk factor for periodontal disease.

Patients with psoriasis had significantly worse periodontal health than those without psoriasis, they found. In the matched analysis, patients with psoriasis had worse bleeding on probing and community periodontal index scores than their peers without psoriasis. They also reported significantly more bleeding when brushing their teeth.

The second, logistic regression analysis confirmed this association. The presence of psoriasis was a significant risk factor for worse bleeding on probing and CPI scores, even after adjusting for other potential confounding factors.

"Psoriasis patients showed significantly higher values for parameters addressing periodontal inflammation," the authors wrote. "Psoriasis management should, therefore, include regular dental checks on periodontal status and respective treatment where required."

Including dental care in psoriasis care

One major limitation of the study was that the matching process limited the patient sample size by half. However, the matching process was needed because some confounding factors can greatly impact periodontal health, according to the authors. For instance, they found a significant association between periodontal health and psoriasis status when the groups were matched for smoking status; however, the significance was not as strong as before the matching process.

Overall, the study findings suggest that psoriasis and periodontal disease may be linked. The authors recommended that patients with psoriasis include dental care as part of their treatment routine.

"The results of this investigation together with recently published data provide a sound basis to recommend regular dental checks on periodontal status and to initiate periodontal treatment where required," the authors wrote. "Future studies should investigate on a long-term basis if and to which extent an improvement of the periodontal status would correlate with the clinical course of psoriasis."