Levels of peripheral CD4 + and CD8 + T cells and glycaemic control level in patients with both type 2 mellitus diabetes and stage III-IV periodontitis: a randomized controlled trial in Chinese population.

Objective: The aim of this randomized controlled trial was to investigate the short-term glycated haemoglobin (HbA1c) level and proportional variation of peripheral T-lymphocytes status after subgingival scaling and root planing (SRP) therapy in patients with type 2 diabetes mellitus(T2DM) and stage III-IV periodontitis in Chinese population.

Methods: Fifty-one participants diagnosed T2DM and stage III-IV periodontitis were enrolled. Twenty-seven of them were randomly assigned to receive SRP + OHI treatment immediately and twenty-four only receive OHI and the delayed SRP treatment. Additionally, we divided participants into two stratifications according to initial HbA1c levels. The HbA1c values, proportion of peripheral CD4 + and CD8 + T-lymphocytes, CD4+/CD8 + ratio, and periodontal parameters: plaque index (PI), percentage of bleeding on probing (BOP%), pocket depth (PD) and clinical attachment level (CAL) were measured at baseline, 3 and 6 months.

Results: Forty-eight participants completed the course of our study. At 6-month follow-up, the HbA1c reduction of SRP + OHI group is 0.22 ± 1.12%, greater than 0.07 ± 0.83% of OHI group(P = 0.592). When HbA1c ≥ 7.5%, the HbA1c reduction of SRP + OHI group is 0.74 ± 1.68%, comparing to 0.43 ± 0.91% of OHI group(P = 0.627); when HbA1c < 7.5%, the reductions were - 0.09 ± 0.39 and - 0.17 ± 0.70 respectively(P = 0.716). Both groups showed a slight decrease of peripheral CD4+/CD8 + ratio at 6-month revaluation. An 0.12 ± 0.08 increase of CD4+/CD8 + ratio was observed in SRP + OHI group when HbA1c ≥ 7.5%, which was significantly different to the conrol group(P = 0.040). As to periodontal parameters, PI, BOP% and PD were significantly improved after treatment, while the intergroup analysis in HbA1c ≥ 7.5% group showed no significant reduction of the PI and BOP% s at 6-months.

Conclusion: Participants under hyperglycemia (HbA1c ≥ 7.5%) and stage III-IV periodontitis exhibited higher sensitivity of HbA1c level to SRP treatment. When HbA1c ≥ 7.5%, The peripheral CD4+/CD8 + ratio showed a slight increase in the intervention group while only reduction was found in other groups. And the peripheral CD4+/CD8 + ratio of SRP + OHI group in the HbA1c ≥ 7.5% stratification showed a significant increase while other subgroups all present a subtle decrease.