. | Metformin is contraindicated: MDRD eGFR <30 mL/min/1.73 m2 . | Indeterminant: MDRD eGFR 30–44 mL/min/1.73 m2 . | Metformin is likely safe: MDRD eGFR ≥45 mL/min/1.73 m2 . | ||||
---|---|---|---|---|---|---|---|
Of study N = 122 . | Of national estimate N = 444,800 . | Of study N = 170 . | Of national estimate N = 734,900 . | Of study N = 50 . | Of national estimate N = 148,700 . | P (χ2 or ANOVA)*** . | |
Male sex | 54 (44.3) | 158,300 | 97 (57.1) | 384,533 | 48 (96.0) | 139,200 | <0.001 |
Age (years) | 0.00 | ||||||
20–39 | 1 (0.8) | 5,700 | 0 (0.0) | 0 | 2 (4.0) | 8,100 | |
40–59 | 18 (14.8) | 77,300 | 13 (7.7) | 63,300 | 5 (10.0) | 38,200 | |
60–69 | 40 (32.8) | 117,600 | 44 (25.9) | 206,400 | 23 (46.0) | 64,400 | |
70+ | 63 (51.6) | 244,200 | 113 (66.5) | 465,200 | 20 (40.0) | 38,000 | |
Race/ethnicity** | <0.001 | ||||||
White | 41 (33.6) | 257,300 | 96 (56.5) | 546,400 | 5 (10.0) | 32,400 | |
Non-Hispanic black | 40 (32.8) | 103,100 | 44 (25.9) | 125,900 | 40 (80.0) | 86,400 | |
Hispanic | 33 (27.1) | 39,400 | 22 (12.9) | 35,200 | 3 (6.0) | 1,900 | |
Yearly family income ($) | 2 (4.0) | 0.20 | |||||
<20,000 | 38 (35.2) | 117,700 | 72 (47.1) | 300,000 | 14 (30.4) | 39,200 | |
20,000–44,999 | 51 (47.2) | 214,000 | 51 (33.3) | 220,000 | 20 (43.5) | 43,300 | |
45,000–74,999 | 14 (13.0) | 48,000 | 19 (12.4) | 86,500 | 8 (17.4) | 30,100 | |
≥75,000 | 5 (4.6) | 23,000 | 11 (7.2) | 56,100 | 4 (8.7) | 30,700 | |
Has health insurance | 118 (96.7) | 438,600 | 163 (95.9) | 701,500 | 46 (92.0) | 136,500 | 0.37 |
More than high school education | 49 (49.5) | 208,200 | 66 (50.0) | 334,600 | 22 (55.0) | 89,300 | 0.82 |
Hypertension* | 100 (82.6) | 365,100 | 127 (75.2) | 570,300 | 40 (81.6) | 123,200 | 0.27 |
Glycemic control: A1C | 0.32 | ||||||
<7% (<53 mmol/mol) | 74 (61.2) | 295,200 | 99 (58.2) | 444,200 | 27 (54.0) | 78,000 | |
7–<8% (53–63 mmol/mol) | 27 (22.3) | 83,700 | 40 (23.5) | 183,300 | 7 (14.0) | 18,000 | |
8–<9% (64–74 mmol/mol) | 20 (8.3) | 28,000 | 16 (9.4) | 65,300 | 7 (14.0) | 10,700 | |
≥9% (>75 mmol/mol) | 10 (8.3) | 35,300 | 15 (8.8) | 42,400 | 9 (18.0) | 41,900 | |
BMI (kg/m2), mean (SD) | 31.7 (6.5) | — | 33.3 (9.1) | — | 32.4 (8.9) | — | 0.31 |
Urine albumin-to-creatinine ratio (mg/g) | <0.001 | ||||||
≤30 | 18 (18.2) | 63,500 | 66 (42.0) | 312,700 | 19 (39.6) | 63,700 | |
31–299 | 32 (32.2) | 151,800 | 60 (38.3) | 229,300 | 19 (39.6) | 53,300 | |
300–1,000 | 14 (14.1) | 49,100 | 13 (8.3) | 65,600 | 6 (12.5) | 13,600 | |
>1,000 | 35 (35.4) | 117,300 | 18 (11.5) | 78,800 | 4 (8.3) | 14,000 |
. | Metformin is contraindicated: MDRD eGFR <30 mL/min/1.73 m2 . | Indeterminant: MDRD eGFR 30–44 mL/min/1.73 m2 . | Metformin is likely safe: MDRD eGFR ≥45 mL/min/1.73 m2 . | ||||
---|---|---|---|---|---|---|---|
Of study N = 122 . | Of national estimate N = 444,800 . | Of study N = 170 . | Of national estimate N = 734,900 . | Of study N = 50 . | Of national estimate N = 148,700 . | P (χ2 or ANOVA)*** . | |
Male sex | 54 (44.3) | 158,300 | 97 (57.1) | 384,533 | 48 (96.0) | 139,200 | <0.001 |
Age (years) | 0.00 | ||||||
20–39 | 1 (0.8) | 5,700 | 0 (0.0) | 0 | 2 (4.0) | 8,100 | |
40–59 | 18 (14.8) | 77,300 | 13 (7.7) | 63,300 | 5 (10.0) | 38,200 | |
60–69 | 40 (32.8) | 117,600 | 44 (25.9) | 206,400 | 23 (46.0) | 64,400 | |
70+ | 63 (51.6) | 244,200 | 113 (66.5) | 465,200 | 20 (40.0) | 38,000 | |
Race/ethnicity** | <0.001 | ||||||
White | 41 (33.6) | 257,300 | 96 (56.5) | 546,400 | 5 (10.0) | 32,400 | |
Non-Hispanic black | 40 (32.8) | 103,100 | 44 (25.9) | 125,900 | 40 (80.0) | 86,400 | |
Hispanic | 33 (27.1) | 39,400 | 22 (12.9) | 35,200 | 3 (6.0) | 1,900 | |
Yearly family income ($) | 2 (4.0) | 0.20 | |||||
<20,000 | 38 (35.2) | 117,700 | 72 (47.1) | 300,000 | 14 (30.4) | 39,200 | |
20,000–44,999 | 51 (47.2) | 214,000 | 51 (33.3) | 220,000 | 20 (43.5) | 43,300 | |
45,000–74,999 | 14 (13.0) | 48,000 | 19 (12.4) | 86,500 | 8 (17.4) | 30,100 | |
≥75,000 | 5 (4.6) | 23,000 | 11 (7.2) | 56,100 | 4 (8.7) | 30,700 | |
Has health insurance | 118 (96.7) | 438,600 | 163 (95.9) | 701,500 | 46 (92.0) | 136,500 | 0.37 |
More than high school education | 49 (49.5) | 208,200 | 66 (50.0) | 334,600 | 22 (55.0) | 89,300 | 0.82 |
Hypertension* | 100 (82.6) | 365,100 | 127 (75.2) | 570,300 | 40 (81.6) | 123,200 | 0.27 |
Glycemic control: A1C | 0.32 | ||||||
<7% (<53 mmol/mol) | 74 (61.2) | 295,200 | 99 (58.2) | 444,200 | 27 (54.0) | 78,000 | |
7–<8% (53–63 mmol/mol) | 27 (22.3) | 83,700 | 40 (23.5) | 183,300 | 7 (14.0) | 18,000 | |
8–<9% (64–74 mmol/mol) | 20 (8.3) | 28,000 | 16 (9.4) | 65,300 | 7 (14.0) | 10,700 | |
≥9% (>75 mmol/mol) | 10 (8.3) | 35,300 | 15 (8.8) | 42,400 | 9 (18.0) | 41,900 | |
BMI (kg/m2), mean (SD) | 31.7 (6.5) | — | 33.3 (9.1) | — | 32.4 (8.9) | — | 0.31 |
Urine albumin-to-creatinine ratio (mg/g) | <0.001 | ||||||
≤30 | 18 (18.2) | 63,500 | 66 (42.0) | 312,700 | 19 (39.6) | 63,700 | |
31–299 | 32 (32.2) | 151,800 | 60 (38.3) | 229,300 | 19 (39.6) | 53,300 | |
300–1,000 | 14 (14.1) | 49,100 | 13 (8.3) | 65,600 | 6 (12.5) | 13,600 | |
>1,000 | 35 (35.4) | 117,300 | 18 (11.5) | 78,800 | 4 (8.3) | 14,000 |
Data are n (%) or n unless otherwise indicated. FDA ineligible for metformin: sCr ≥1.4 mg/dL for women and ≥1.5 mg/dL for men. Sample size = 342; weights used to produce U.S. national estimates. Diabetes is self-reported or A1C >6.5%.
***P values refer to differences among actual study participants—not national estimates.
**“Other” not shown owing to small sample size but included in all analyses.
*Hypertension defined by average blood pressure >140/90 mmHg or self-reported antihypertensive use.