Association Between Diabetes Mellitus and Periodontal Disease Severity: A Systematic Review and Meta-Analysis
Abstract
Background: Diabetes mellitus (DM) and periodontal disease share a complex, clinically significant relationship. Patients with DM exhibit greater periodontal destruction, reflected by deeper probing pocket depths (PPD), greater clinical attachment loss (CAL), and higher rates of alveolar bone resorption. Despite substantial evidence globally, the magnitude of this association across diverse populations—particularly those in Saudi Arabia and the Gulf Cooperation Council (GCC) region, where DM prevalence is among the highest in the world—remains incompletely characterized in synthesized form. Objective: To quantify the association between DM and periodontal disease severity through a systematic review and meta-analysis of existing systematic reviews and high-quality observational studies, and to contextualize findings within the Saudi and GCC regional epidemiological landscape. Methods: PubMed/MEDLINE, Scopus, EMBASE, and the Cochrane Library were searched through December 2024 following PRISMA 2020 guidelines. Included records were systematic reviews and meta-analyses of observational studies reporting periodontal disease severity outcomes (PPD, CAL, bone loss, tooth loss, or OR/RR for periodontitis) in patients with DM compared with non-diabetic controls. A random-effects model (DerSimonian–Laird) was used to pool odds ratios. Heterogeneity was assessed with I², Q-statistic, and τ². Publication bias was evaluated using Egger's test and a funnel plot. Results: Eighteen systematic reviews or meta-analyses met the inclusion criteria; five provided extractable pooled odds ratios or relative risks suitable for quantitative synthesis. Patients with DM had significantly higher odds of severe periodontitis compared with non-diabetic individuals (pooled OR = 1.65; 95% CI: 1.30–2.09; I² = 85.6%; p < 0.001). Mean PPD was 0.23–0.61 mm deeper and mean CAL was 0.51–1.00 mm greater in DM patients across included meta-analyses. The association held for both type 1 DM (pooled OR = 2.12; 95% CI: 1.42–3.16) and type 2 DM (pooled OR = 1.63; 95% CI: 1.34–1.99). Saudi and GCC data confirmed high burden: diabetic adults in Saudi Arabia had a 52.1% prevalence of periodontal disease versus 46.2% in the general population. No significant publication bias was detected (Egger's test p = 0.14). Conclusion: Strong and consistent evidence across diverse populations confirms that DM significantly worsens periodontal disease severity across multiple clinical parameters. The bidirectional nature of this relationship underscores the need for integrated oral and diabetes care. Regional healthcare systems in Saudi Arabia, the GCC, and comparable high-DMburden settings should prioritize routine periodontal screening for all diabetic patients and integrate dental professionals into multidisciplinary diabetes management teams.