Association of the dietary inflammation index (DII) with the prevalence of chronic kidney disease in patients with type-2 diabetes mellitus

Figures & data

Figure 1. Flowchart of the study design.

Table 1. Baseline study population characteristics (weighted).

Characteristics	Overall (N = 7,974)	T1 group (N = 2,658)	T2 group (N = 2,658)	T3 group (N = 2,658)	p-value
Age, years	59.5 (0.3)	59.0 (0.4)	59.6 (0.4)	60.0 (0.4)	0.227
Female, n (%)	3,843 (48.9)	1,003 (36.2)	1,253 (49.8)	1,587 (62.5)	<0.001
Race, n (%)					<0.001
Mexican American	1,637 (9.4)	607 (10.1)	546 (9.4)	484 (8.6)
Non-Hispanic Black	1,955 (14.3)	523 (11.0)	667 (14.9)	765 (17.7)
Non-Hispanic White	2,980 (62.4)	1,045 (65.3)	964 (61.5)	971 (59.9)
Other Hispanic	748 (5.9)	222 (5.1)	273 (6.5)	253 (6.3)
Other Race	654 (8.0)	261 (8.5)	208 (7.8)	185 (7.5)
DII	1.6 (0.0)	–0.4 (0.0)	2.0 (0.0)	3.5 (0.0)	<0.001
Glu, mmol/L	8.10 (0.1)	8.14 (0.1)	8.14 (0.1)	8.03 (0.1)	0.743
HbA1c, %	7.15 (0.03)	7.13 (0.1)	7.19 (0.1)	7.113 (0.1)	0.568
Smoking status, n (%)	4,031 (51.1)	1,294 (50.1)	1,374 (51.0)	1,363 (52.5)	0.465
Drinking status, n (%) *	3,905 (58.7)	1,479 (63.9)	1,295 (59.0)	1,131 (52.2)	<0.001
BMI, kg/m^2	32.7 (0.1)	32.3 (0.2)	32.8 (0.2)	33.1 (0.3)	0.014
eGFR, ml/min/1.73m^2	83.0 (0.4)	85.5 (0.7)	82.71 (0.7)	80.43 (0.8)	<0.001
uACR, mg/g	125.8 (8.2)	99.8 (9.9)	140.6 (14.1)	140.4 (15.0)	0.019
TG, mmol/L	2.3 (0.0)	2.3 (0.1)	2.4 (0.1)	2.2 (0.1)	0.020
TC, mmol/L	4.9 (0.0)	4.8 (0.0)	5.0 (0.0)	5.0 (0.0)	0.008
CRP, mg/dL	0.7 (0.0)	0.5 (0.0)	0.7 (0.0)	0.8 (0.0)	<0.001
Energy intake, Kcal/day	1,933.3 (16.4)	1,879.6 (20.2)	1,385.0 (17.4)	2,460.5 (26.8)	<0.001
MET, minutes/week	2,832.4 (96.4)	2,982.6 (142.3)	2,841.2 (163.1)	2,609.0 (158.6)	0.183
Hypoglycemic drugs, n (%)	4,941 (61.1)	1,653 (60.8)	1,657 (64.0)	1,631 (58.5)	0.038
Hypertension, n (%)	5,748 (70.4)	1,836 (67.4)	1,915 (70.1)	1,997 (74.1)	0.003
CVD, n (%)	2,065 (25.0)	589 (22.1)	707 (25.4)	769 (27.9)	0.003
CKD, n (%)	3,357 (38.1)	1,012 (33.0)	1,112 (37.8)	1,233 (44.3)	<0.001

DII: dietary inflammatory index; Glu: glucose; BMI: body mass index; eGFR: estimated glomerular filtration rate; uACR: urinary albumin-to-creatinine ratio; TG: triglycerides; TC: total cholesterol; CRP: C-reactive protein; Met: metabolic equivalent; CVD: cardiovascular disease (including coronary heart disease: congestive heart failure: heart attack: stroke: and angina); CKD: chronic kidney disease.

Values are n (%) or mean (SE).

*The average number of alcohol-containing beverages consumed per day over the past 12 months.

Figure 2. The distribution of all CKD categories (weighted).

Table 2. The association between the DII and CKD in patients with DM (weighted).

Variable		Model 1		Model 2		Model 3
		OR* (95%CI^#)	P-value	OR (95%CI)	p-value	OR (95%CI)	p-value
Continuous variables
DII		1.14 (1.10–1.18)	<0.001	1.14 (1.10–1.18)	<0.001	1.15 (1.09–1.22)	<0.001
Categorical variable	Number of cases /All population
T 1 group	1,012/2,658	Ref		Ref		Ref
T 2 group	1,112/2,658	1.24 (1.04–1.47)	0.015	1.23 (1.03–1.47)	0.021	1.40 (1.10–1.76)	0.006
T 3 group	1,233/2,658	1.62 (1.37–1.91)	<0.001	1.63 (1.39–1.92)	<0.001	1.67 (1.29–2.17)	<0.001

*Odds ratio. Confidence interval.^#

Model 1: Not adjusted. Model 2: Adjusted by age, gender, race/ethnicity. Model 3: Adjusted by age, gender, race/ethnicity, cigarette smoking status, alcohol consumption status, body mass index, triglycerides level, total cholesterol level, total metabolic equivalent, energy intake, hypoglycemic medication, hypertension and cardiovascular disease.

Figure 3. Potential nonlinear relationship between the DII and CKD (weighted).

Figure 4. Association between the DII and CKD by the selected subgroups (weighted).

Availability of data and materials

All data are available as publicly accessible datasets through the NHANES, and they can be accessed through the following link: https://wwwn.cdc.gov/nchs/nhanes/.