Table 2. Incidence rates of oral cancer and hazard ratios by sitagliptin exposure.

Sitagliptin use	Cases followed	Incident cases of oral cancer	Person-years	Incidence rate (per 100,000 person-years)	Hazard ratio	95% Confidence interval	P-value
Never users	39195	54	71353.08	75.68	1.000
Ever users	39195	52	71839.78	72.38	0.956	(0.652−1.401)	0.8173
Cumulative duration (months)
Never users	39195	54	71353.08	75.68	1.000
< 7.47	13324	24	21264.36	112.86	1.563	(0.963−2.537)	0.0708
7.47−15.63	12533	20	21879.55	91.41	1.236	(0.738−2.071)	0.4204
> 15.63	13338	8	28695.87	27.88	0.345	(0.164−0.725)	0.0050
Cumulative dose (mg)
Never users	39195	54	71353.08	75.68	1.000
< 19,600	12716	23	20366.50	112.93	1.575	(0.963−2.575)	0.0703
19,600−42,200	13135	21	22845.36	91.92	1.224	(0.738−2.033)	0.4335
> 42,200	13344	8	28627.92	27.94	0.347	(0.165−0.731)	0.0053
Sensitivity analyses after excluding patients who developed any other cancer during follow−up
Never users	38256	52	69499.80	74.82	1.000
Ever users	38180	49	69916.09	70.08	0.938	(0.634−1.388)	0.7486
Cumulative duration (months)
Non−users	38256	52	69499.80	74.82	1.000
< 7.47	12927	22	20617.51	106.71	1.496	(0.905−2.471)	0.1161
7.47−15.63	12223	20	21296.44	93.91	1.284	(0.764−2.157)	0.3445
> 15.63	13030	7	28002.15	25.00	0.313	(0.142−0.689)	0.0040
Cumulative dose (mg)
Non−users	38256	52	69499.80	74.82	1.000
< 19,600	12326	21	19725.73	106.46	1.503	(0.902−2.505)	0.1175
19,600−42,200	12824	21	22266.16	94.31	1.269	(0.762−2.113)	0.3595
> 42,200	13030	7	27924.19	25.07	0.316	(0.143–0.695)	0.0042