Baseline characteristics of premier care members ≥18 years of age with pre-diabetes, stratified by the timing of metformin use
| Metformin use before invitation only | Metformin use before and after invitation | Metformin use after invitation only | Overall p value | |
| Number (%) | 107 (1) | 426 (5) | 269 (3) | – |
| Age (years) | 43±12 | 48±12 | 49±11 | <0.0001 |
| Sex | 0.3257 | |||
| Women | 78 (73) | 295 (69) | 176 (65) | |
| Men | 29 (27) | 131 (31) | 93 (35) | |
| Race | 0.0367 | |||
| Asian | 3 (4) | 25 (7) | 15 (7) | |
| Black | 10 (13) | 19 (5) | 22 (11) | |
| White | 62 (83) | 296 (86) | 162 (78) | |
| Other | 0 (0) | 6 (2) | 8 (4) | |
| At least one primary care visit in prior year | 90 (84) | 384 (90) | 217 (81) | 0.0023 |
| At least one specialist visit in prior year | 82 (77) | 304 (71) | 183 (68) | 0.2672 |
| Geocoded Indicators | ||||
| Median neighborhood income ($) | $68 163 | $70 130 | $66 040 | 0.0103 |
| Per cent unemployment | 34.8±5.1 | 34.6±4.4 | 34.8±4.9 | 0.7363 |
| Per cent Supplemental Nutrition Assistance Program | 9.3±6.4 | 8.7±5.7 | 10.0±7.1 | 0.0217 |
| BMI (kg/m2) | 36.1±7.2 | 36.9±7.9 | 36.6±7.8 | 0.5938 |
| Blood pressure (mm Hg) | ||||
| Systolic | 126±13 | 127±14 | 127±16 | 0.6425 |
| Diastolic | 77±10 | 76±10 | 77±11 | 0.9817 |
| Lipids (mg/dL) | ||||
| Total cholesterol | 190±40 | 189±39 | 191±41 | 0.9502 |
| HDL cholesterol | 47±14 | 49±13 | 49±13 | 0.6366 |
| Women | 51±16 | 53±12 | 52±13 | 0.6491 |
| Men | 40±8 | 42±11 | 41±9 | 0.7108 |
| Triglycerides | 146±72 | 165±138 | 159±88 | 0.4733 |
| LDL cholesterol | 114±32 | 110±34 | 111±35 | 0.6747 |
| HbA1c (%) | 5.9±0.5 n=80 (74) | 6.2±1.0 n=367 (86) | 6.1±0.8 n=178 (66) | 0.0525 |
| Claims diagnosis of … | ||||
| Overweight/obesity | 55 (51) | 228 (54) | 135 (50) | 0.6837 |
| Hypertension | 38 (36) | 214 (50) | 119 (44) | 0.0173 |
| Any antihypertensive medication | 41 (38) | 225 (53) | 110 (41) | 0.0015 |
| Dyslipidemia | 40 (37) | 161 (38) | 89 (33) | 0.4353 |
| Any lipid-lowering medication | 16 (15) | 128 (30) | 62 (23) | 0.0029 |
| Smoking | 4 (4) | 25 (6) | 19 (7) | 0.4663 |
| Women | 0 (0) | 14 (5) | 10 (6) | 0.1115 |
| Men | 4 (14) | 11 (8) | 9 (10) | 0.6665 |
| Cardiovascular disease | 10 (9) | 34 (8) | 37 (14) | 0.0466 |
Data are number (%) or mean±SD.
BMI, body mass index; HbA1c, hemoglobin A1c; HDL, high density lipoprotein; LDL, low density lipoprotein.