Calcium channel blocker (CCB) is commonly used in the treatment of cardiovascular diseases. It is reported that the prevalence of drug-induced gingival overgrowth (DIGO) is 7.3%-77.6%. The results obtained from some studies are quite different. The purpose of this study was to clarify the relationship between CCB and DIGO and its influencing factors through systematic reviews and Meta-analysis.

Two independent researchers systematically searched PubMed, Cochrane Library, CBM (China Biology Medicine) , CNKI, and Wanfang for clinical studies of DIGO caused by CCB (published from January 1, 1984 to November 30, 2019; no language restrictions) . With each eligible study data extracted, the relative risk (RR) and 95% confidence interval (95% CI) were used for the analysis of systematic review to assess the probability and risk factors of gingival hyperplasia caused by CCB.

We obtained 921 articles through searching and 13 articles were included in the Meta-analysis (n = 4432 participants) . The Meta-analysis results showed that the probability of gingival hyperplasia in subjects taking CCB was 4.55 times that of those without CCB [RR = 4.55, 95% CI (3.25, 6.36) , I² = 57%, P = 0.006]. The results of the subgroup analysis and the Meta-regression analysis showed that the ′Region′ and ′Diagnostic criteria for gingival hyperplasia′ were the sources of heterogeneity among studies. Different gingival hyperplasia diagnostic criteria have different combined RR values, and the combined RR value among domestic studies [RR = 5.83, 95% CI (4.11, 8.26) ] was significantly higher than that among foreign studies [RR = 2.91, 95% CI (1.98, 4.29) ].

Taking CCB can lead to gingival hyperplasia. ′Region′ and ′Diagnostic criteria for gingival hyperplasia′ are the main sources of research heterogeneity. Patients taking CCB in China may have a higher risk of gingival hyperplasia, which may be related to poorer periodontal health of the patients. At the same time, factors such as gingival index, bleeding index, and plaque index were related to DIGO caused by CCB. Risk factors in different studies may be inconsistent. Patients who need to take CCB should have periodontal treatment before taking the medicine, which may prevent the occurrence of drug-induced gingival hyperplasia. Periodic periodontal examinations and related periodontal treatments are recommended to be performed regularly to avoid or reduce the degree of DIGO and avoid serious consequences such as loose tooth.