The Influence of Psychological Stress and Stress‐Related Disorders in the Treatment Outcome of Periodontitis: A Systematic Review and Meta‐Analysis

Background and Objective In humans 16 years and above with periodontitis (Population), how do psychological stress and stress‐related disorders (PSRD; Exposure) compared to those without PSRD (Comparison) affect clinical attachment level (CAL) upon periodontitis treatment (Outcome), as observed in experimental studies or descriptive pre–post studies (Study design)? Methods Five major databases were searched for pre–post studies, descriptive cohort and quasi‐experimental or randomised controlled trials (RCTs). For meta‐analysis, mean differences in CAL and bleeding on probing (BOP) were pooled with random‐effects models. Risk of bias, study quality and certainty of evidence were assessed. Results Thirteen studies (eight prospective, two retrospective, two quasi‐experimental and one pilot RCT) with 1610 participants were identified. PSRD (measured as stress in nine studies, depression in three studies and anxiety in one study) showed a negative influence on periodontitis treatment (steps 1 + 2: eight studies, steps 1 + 2 + 3 or 4: four studies, step 4: one study) outcomes. Meta‐analysis of steps 1 + 2 treatment results revealed that patients with PSRD (exposure: stress)—compared to those without—had smaller reductions in CAL (three studies; n = 170; weighted mean difference (WMD) = 0.78 mm; p = 0.01) and probing pocket depth (PPD; three studies; n = 170; WMD = 1.02 mm; p = 0.04) following periodontitis treatment in studies. Conclusion PSRD adversely affected periodontitis treatment outcomes, particularly concerning CAL and PPD, even though our confidence in the effect estimate is limited in the case of CAL and very low in the case of PPD. This conclusion, based on small treatment cohorts and quasi‐experimental studies following steps 1 + 2 of periodontitis treatment over a 3–6‐month period, warrants validation through rigorously designed studies.