Table 3.

Risk of Incident Dementia among Participants without and Those with Diabetes, According to Glucose Values Averaged over the Preceding 5 Years and the Period between 5 and 8 Years Earlier.^*

Average Glucose Level	Hazard Ratio for Dementia (95% CI)
Participants without diabetes
Preceding 5 yr
95 mg/dl	0.88 (077–1.00)
100 mg/dl	1.00
105 mg/dl	1.09 (1.01–1.17)
110 mg/dl	1.14 (1.01–1.27)
115 mg/dl	1.16 (1.00–1.35)
P value	0.09
Between 5 and 8 yr earlier
95 mg/dl	0.94 (0.81–1.08)
100 mg/dl	1.00
105 mg/dl	1.03 (0.95–1.10)
110 mg/dl	1.02 (0.91–1.15)
115 mg/dl	1.01 (0.85–1.20)
P value	0.65
Participants with diabetes
Preceding 5 yr
150 mg/dl	1.15 (0.94–1.42)
160 mg/dl	1.00
170 mg/dl	0.96 (0.85–1.10)
180 mg/dl	1.04 (0.84–1.28)
190 mg/dl	1.20 (0.89–1.62)
P value	0.06
Between 5 and 8 yr earlier
150 mg/dl	0.92 (0.79–1.07)
160 mg/dl	1.00
170 mg/dl	1.06 (0.96–1.18)
180 mg/dl	1.10 (0.91–1.34)
190 mg/dl	1.13 (0.85–1.50)
P value	0.52

^*Estimates were adjusted for age at study entry, study cohort, sex, educational level, time-varying measures of exercise level, average systolic and diastolic blood pressure, and status with respect to coronary artery disease, cerebrovascular disease, atrial fibrillation, treatment for hypertension, and smoking. The associations between glucose levels and the risk of dementia were modeled with the use of natural cubic splines, with separate splines for distant levels (5 to 8 years) and recent levels (up to 5 years). The P values are based on omnibus tests of the composite hypothesis that all regression model parameters corresponding to the spline were equal to zero. As such, these P values reflect the significance for tests of the null hypothesis that there was no association between glucose level and risk of dementia, with distinct values for participants with diabetes and those without diabetes.