Periodontal disease is associated with increased coronary heart disease risk: A meta-analysis based on 38 case-control studies

Table 3 Results of overall and subgroups analyses of pooled odds ratios and 95%CIs

Total and subgroup	No. of trials	Heterogeneity		Model	Meta-analysis
		I2 (%)	P		OR	95%CI	P
Total	38	98.59	< 0.001	Random	3.79	2.23-6.43	< 0.001
Adjustment for covariates
Yes	21	66.02	< 0.001	Random	2.72	2.13-3.46	< 0.001
No	17	98.68	< 0.001	Random	4.62	2.10-10.18	< 0.001
Source of control
HB	22	98.5	< 0.001	Random	4.04	2.00-8.12	< 0.001
PB	16	80.38	< 0.001	Random	3.08	2.23-4.26	< 0.001
Methodological quality (NOS)
< 6	11	83.28	< 0.001	Random	3.38	1.75-6.52	< 0.001
≥ 6	27	98.73	< 0.001	Random	4.16	2.71-6.40	< 0.001
End point
CHD	31	98.75	< 0.001	Random	3.63	2.00-6.59	< 0.001
MI	7	70.15	< 0.001	Random	4.12	2.35-7.22	< 0.001
Assessment of PD
ABL	8	97.93	< 0.001	Random	5.57	1.90-16.33	< 0.001
CAL	10	0	0.5	Fixed	2.54	2.13-3.04	< 0.001
CPI	5	90.24	< 0.001	Random	2.76	1.45-5.23	< 0.001
PI	5	91.95	< 0.001	Random	3.12	1.38-7.05	< 0.001
PPD	8	0	0.76	Fixed	3.55	2.39-5.27	< 0.001
Questionnaire	2	0	0.86	Fixed	2.19	1.73-2.77	< 0.001
Assessment of CHD
CAG	22	73.04	< 0.001	Random	2.85	2.23-3.64	< 0.001
Cardiologists	10	99	< 0.001	Random	5.09	1.71-15.14	< 0.001
ECG	6	60.72	0.03	Random	3.55	2.06-6.12	< 0.001
Ethnicity
America	4	88.24	< 0.001	Random	4.75	1.50-15.02	0.01
Asia	23	99.01	< 0.001	Random	3.46	1.73-6.94	< 0.001
Europe	11	56.82	0.01	Random	3.81	2.46-5.91	< 0.001

PD: Periodontal disease; CHD: Coronary heart disease; NOS: Newcastle-Ottawa Scale; OR: Odds ratio; CAG: Coronary arteriography; ECG: Electrocardiograph; MI: Myocardial infarction; CAL: Clinical attachment loss; PPD: Periodontal pocket depth; ABL: Alveolar bone loss; CPI: Community periodontal index; PI: Periodontal index.