Table 1.
Characteristics of Adults with Type 2 Diabetes Seen in Primary Care or Endocrinology Clinics at Vanderbilt University Medical Center in 2021, by Continuous Glucose Monitor (CGM) Use
| Mean (SD) or % (n) | Total cohort | No CGM use | CGM use | p value |
|---|---|---|---|---|
| N = 30,585 | n = 26,692 | n = 3893 | ||
| Age, years | 62.5 (13.7) | 63.3 (13.5) | 57.5 (13.5) | < 0.001 |
| Female gender | 50.6 (15,573) | 50.6% (13,501) | 50.7% (1973) | 0.921 |
| Race | 0.154 | |||
| White | 72.3% (22,109) | 72.1% (19,255) | 73.3% (2854) | |
| Black | 18.0% (5489) | 17.8% (4742) | 19.2% (747) | |
| Asian | 2.3% (693) | 2.3% (613) | 2.1% (80) | |
| American Indian | 0.2% (62) | 0.2% (55) | 0.2% (7) | |
| Native Hawaiian | 0.1% (27) | 0.1% (20) | 0.2% (7) | |
| Multiple | 0.7% (222) | 0.7% (189) | 0.9% (33) | |
| Missing | 6.5% (1983) | 6.8% (1818) | 4.2% (165) | |
| Hispanic ethnicity | 3.1% (954) | 3.2% (842) | 2.9% (112) | 0.167 |
| Insurance status | < 0.001 | |||
| Government | 44.4% (13,582) | 46.7% (12,464) | 28.7% (1118) | |
| Private | 52.7% (16,114) | 50.3% (13,437) | 68.8% (2677) | |
| Other | 2.0% (598) | 1.9% (501) | 2.5% (97) | |
| 2021 visit type(s) | < 0.001 | |||
| Primary care | 59.6% (18,239) | 65.0% (17,337) | 23.2% (902) | |
| Endocrinology | 19.7% (6015) | 17.3% (4624) | 35.7% (1391) | |
| Both | 20.7% (6331) | 17.7% (4731) | 41.1% (1600) | |
| Insulin type | < 0.001 | |||
| None | 48.7% (14,892) | 54.0% (14,413) | 12.3% (479) | |
| Basal | 6.9% (2113) | 6.9% (1828) | 7.3% (285) | |
| Prandial* | 12.6% (3849) | 13.2% (3526) | 8.3% (323) | |
| Both | 31.8% (9731) | 25.9% (6925) | 72.1% (2806) | |
| Most recent HbA1c (%)† | 7.4 (1.7) | 7.3 (1.7) | 8.0 (1.8) | < 0.001 |
| HbA1c ≥ 8.5% | 19.2% (5207) | 17.1% (3963) | 32.3% (1244) | |
| HbA1c (%) prior to first CGM prescription‡ | NA | NA | 8.6 (2.0) | NA |
| HbA1c ≥ 8.5% | NA | NA | 46.1% (1564) |
Nonparametric tests of difference used (e.g., Wilcoxon rank sum Kruskal–Wallis test)
NA not applicable, SD standard deviation
*We were unable to differentiate those using prandial insulin with an insulin pump from those on multiple daily injections
†88.5% (27,074/30,585) had a recent HbA1c value; 87.0% (23,221/26,692) no CGM use and 98.5% CGM use (3835/3893)
‡95.8% (3729/3893) of CGM users had a HbA1c value prior to first CGM prescription. We excluded HbA1c values more than 7 months before the first CGM prescription (n = 338), resulting in 3391/3893 CGM users with an HbA1c within 7 months of their first CGM prescription who were included in this calculation