The Interaction Between Age and Risk Factors for Diabetes and Prediabetes: A Community-Based Cross-Sectional Study

Figures & data

Figure 1 Participants selection flow diagram.

Table 1 General Characteristics of Study Participants

Variable	Normoglycemic	Prediabetic	Diabetic	P value
n (%)	904 (32.6)	1451 (52.3)	421 (15.1)
Age groups^***###				<0.001
Middle-aged group	366 (40.5)	423 (29.2)	126 (29.9)
Elderly group	538 (59.5)	1028 (70.8)	295 (70.1)
Gender(female)^##	616 (68.1)	1022 (70.4)	253 (60.1)	<0.001
Educational level^*##				0.015
Junior high school and below	651 (72.0)	972 (67.0)	270 (64.1)
Senior high school and technical college	195 (21.6)	368 (25.4)	124 (29.5)
University and above	57 (6.3)	111 (7.6)	27 (6.4)
Family history of diabetes^***###	208 (23.0)	460 (31.7)	246 (58.4)	<0.001
Alcohol drinking^***###	420 (46.5)	832 (57.3)	244 (58.0)	<0.001
Cigarette smoking^***###	426 (47.1)	840 (57.9)	247 (58.7)	<0.001
Clinical characteristics
Body mass index (BMI)^***###				<0.001
BMI<24 kg/m^2	483 (53.4)	645 (44.5)	138 (32.8)
24 kg/m^2≤BMI <28 kg/m^2	376 (41.6)	700 (48.2)	218 (51.8)
BMI≥28 kg/m^2	45 (5.0)	106 (7.3)	65 (15.4)
Hypertension^***###	276 (30.5)	564 (38.9)	223 (53.0)	<0.001
FPG (mmol/l)^***###	4.70 (4.41–4.95)	4.98 (4.67–5.35)	6.15 (5.45–7.12)	<0.001
2hPG (mmol/l)^***###	5.68 (4.91–6.45)	7.02 (5.84–8.33)	12.30 (10.41–14.19)	<0.001
FINS (mIU/l)^***###	6.29 (4.41–8.96)	7.60 (5.40–10.45)	9.51 (6.43–13.60)	<0.001
HOMA-IR^***###	1.31 (0.91–1.90)	1.65 (1.16–2.38)	2.65 (1.78–3.93)	<0.001
HbA1c(%)^***###	5.40 (5.30–5.50)	5.90 (5.70–6.00)	6.60 (6.25–7.10)	<0.001
TC(mmol/l)^***#	4.92±0.91	5.09±0.90	5.01±0.99	<0.001
HDL-C (mmol/l)^**###	1.45 (1.21–1.76)	1.40 (1.17–1.68)	1.26 (1.07–1.53)	<0.001
LDL -C (mmol/l)***	2.77±0.80	2.89±0.83	2.76±0.80	<0.001
TG (mmol/l)^***###	1.19 (0.88–1.70)	1.37 (1.02–1.95)	1.68 (1.23–2.38)	<0.001
SCr (μmol/l)	66.0 (58.0–77.0)	66.0 (58.0–77.0)	66.0 (57.5–78.0)	0.705
SUA (μmol/l)^***###	288.5 (245.0–343.0)	306.0 (261.0–359.0)	319.0 (270.0–375.0)	<0.001

Notes: ***P < 0.001; **P < 0.01; *P < 0.05 for comparison of the prediabetic and normoglycemic. ^###P < 0.001; ^##P < 0.01; ^#P < 0.05 for comparison of the diabetic and normoglycemic.

Table 2 Characteristics of Participants in Middle-Aged and Elderly Groups

Variable	Unmatched			Matched
	Middle-Aged Group	Elderly Group	P value	Middle-Aged Group	Elderly Group	P value
n (%)	915 (33.0)	1861 (67.0)		755 (50.0)	755 (50.0)
Glucose metabolism status			<0.001			<0.001
Normoglycemic	366 (40.0)	538 (28.9)		305 (40.3)	170 (22.5)
Prediabetic	423 (46.2)	1028 (55.2)		367 (48.6)	519 (68.7)
Diabetic	126 (13.8)	295 (15.9)		83 (10.9)	66 (8.7)
Gender (female)	655 (71.6)	1236 (66.4)	0.006	549 (72.7)	549 (72.7)	1.000
Educational level			<0.001			1.000
Junior high school and below	555 (60.7)	1338 (71.9)		495 (65.5)	495 (65.5)
Senior high school and technical college	252 (27.5)	436 (23.4)		205 (27.1)	205 (27.1)
University and above	108 (11.8)	87 (4.7)		55(7.2)	55(7.2)
Family history of diabetes	280 (30.6)	634 (34.1)	0.068	206 (27.3)	206 (27.3)	1.000
Alcohol drinking	513 (56.1)	983 (52.8)	0.107	418 (55.3)	418 (55.3)	1.000
Cigarette smoking	517 (56.5)	996 (53.5)	0.138	419 (55.5)	419 (55.5)	1.000
Clinical characteristics
BMI (kg/m^2)			0.134			1.000
BMI<24	442 (48.3)	824 (44.3)		368 (48.7)	368 (48.7)
24 ≤BMI <28	405 (44.3)	889 (47.8)		350 (46.3)	350 (46.3)
BMI≥28	68 (7.4)	148 (8.0)		37 (4.9)	37 (4.9)
Hypertension	267 (29.2)	796 (42.8)	<0.001	220 (29.1)	220 (29.1)	1.000
FPG (mmol/l)	4.92 (4.60–5.36)	4.95 (4.60–5.42)	0.195	4.91 (4.59–5.32)	4.95 (4.62–5.35)	0.205
2hPG (mmol/l)	6.27 (5.29–7.99)	6.87 (5.67–8.70)	<0.001	6.25 (5.32–7.72)	6.78 (5.68–8.29)	<0.001
FINS(mIU/l)	7.32 (5.02–10.30)	7.33 (5.19–10.52)	0.308	7.33 (5.08–10.09)	7.29 (5.19–10.32)	0.499
HOMA-IR	1.64 (1.08–2.38)	1.63 (1.11–2.44)	0.264	1.63 (1.08–2.35)	1.60 (1.09–2.39)	0.455
HbA1c(%)	5.70 (5.40–6.00)	5.80 (5.50–6.10)	<0.001	5.70 (5.40–5.90)	5.80 (5.60–6.00)	<0.001
TC > 5.18 (mmol/l)	360 (39.3)	829 (44.5)	0.009	262 (35.3)	262 (35.3)	1.000
HDL-C <1.04 (mmol/l)	140 (15.3)	248 (13.3)	0.158	86 (11.6)	86 (11.6)	1.000
LDL -C > 3.37 (mmol/l)	210 (22.9)	480 (25.7)	0.103	150 (20.2)	150 (20.2)	1.000
TG > 1.70 (mmol/l)	292 (31.9)	654 (35.1)	0.091	210 (28.3)	210 (28.3)	1.000
SCr (μmol/l)	65.0 (57.0–75.0)	67.0 (59.0–79.0)	<0.001	65.0 (57.0–75.0)	65.0 (58.0–75.0)	0.517
SUA ≥ 420 (μmol/l)	75 (8.2)	178 (9.5)	0.239	58 (7.4)	58 (7.4)	1.000

Table 3 The Effect of Age on the Risk of Prediabetes and Diabetes

Variable	Prediabetic vs Normoglycemic		Diabetic vs Normoglycemic
	OR (95% CI)	P value	OR (95% CI)	P value
Unmatched
Middle-aged	Reference		Reference
Elderly	1.653 (1.389–1.969)	<0.001	1.593 (1.244–2.040)	<0.001
Matched
Middle-aged	Reference		Reference
Elderly	2.537 (2.015–3.194)	<0.001	1.427 (0.982–2.073)	0.062

Table 4 Risk Factors for Prediabetes in Different Age Groups

Variable	Middle-Aged Group^a		Elderly Group^b
	OR (95% CI)	P value	OR (95% CI)	P value
Female	-		1.284 (1.023–1.614)	0.031
Senior high school and technical college	2.091 (1.470–2.975)	< 0.001	-
University and above	1.656 (1.040–2.638)	0.034	3.045 (1.637–5.667)	< 0.001
24 kg/m^2 ≤ BMI < 28 kg/m^2	-		1.464 (1.174–1.825)	0.001
BMI ≥ 28 kg/m^2	-		1.755 (1.095–2.814)	0.020
Family history of diabetes	-		1.571(1.232–2.004)	< 0.001
Hypertension	1.451 (1.041–2.022)	0.028	-
TC > 5.18 mmol/l	2.243 (1.631–3.087)	< 0.001	-
TG > 1.70 mmol/l	-		1.517 (1.195–1.925)	0.001

Notes: Model ^aadjusted for educational level, family history of diabetes, BMI, hypertension, TC, LDL-C, TG, SUA; Model ^badjusted for gender, educational level, family history of diabetes, BMI, hypertension, TC, HDL-C, TG, SUA.

Table 5 Risk Factors for Diabetes in Different Age Groups

Variable	Middle-Aged Group^a		Elderly Group^b
	OR (95% CI)	P value	OR (95% CI)	P value
Senior high school and technical college	-		2.749 (1.830–4.130)	< 0.001
Alcohol drinking	3.307 (1.851–5.908)	< 0.001	-
24 kg/m^2 ≤ BMI < 28 kg/m^2	-		2.098 (1.473–2.998)	< 0.001
BMI ≥ 28 kg/m^2	-		4.670 (2.541–8.583)	< 0.001
Family history of diabetes	4.676 (2.900–7.541)	< 0.001	5.666 (4.009–8.009)	< 0.001
Hypertension	3.113 (1.895–5.112)	< 0.001	1.703 (1.213–2.390)	0.002
TG > 1.70 mmol/l	-		3.491 (2.424–5.027)	< 0.001

Notes: Model ^aadjusted for educational level, alcohol drinking, family history of diabetes, BMI, hypertension, TC, HDL-C, TG, SUA; Model ^b adjusted for gender, educational level, family history of diabetes, BMI, hypertension, HDL-C, TG, SUA.

Table 6 Interaction of Age with Other Risk Factors

Variable	Prediabetic			Diabetic
	Middle-Aged	Elderly	P Interaction	Middle-Aged	Elderly	P Interaction
University and above	Reference	2.216 (1.043–4.711)	0.039	-	-	-
24 kg/m^2 ≤ BMI < 28 kg/m^2	-	-	-	Reference	1.820 (1.068–3.102)	0.028
TC > 5.18 mmol/l	1.539 (1.073–2.209)	Reference	0.019	-	-	-