Baseline Characteristics at Index Date and Results
| Desiccated Thyroid (n = 435) | Synthetic Levothyroxine (n = 435) | P Value | |
|---|---|---|---|
| Age, y (mean, 95% CI) | 63.4 (12.68) | 63.4 (12.68) | Matched |
| Female No. (%) | 392 (90.1) | 392 (90.1) | Matched |
| Race, No. (%) | Matched | ||
| Non-Hispanic White | 363 (83.4) | 363 (83.4) | Matched |
| Non-Hispanic Black | 5 (1.1) | 5 (1.1) | |
| Hispanic | 22 (5.1) | 22 (5.1) | |
| Other | 45 (10.3) | 45 (10.3) | |
| TSH (mean, 95% CI) | 2.4 (0.18) | 3.4 (0.27) | 0.001 |
| BMI (kg/m2) (mean, 95% CI) | 27.55 (5.94) | 28.62 (6.64) | 0.032 |
| Systolic BP (mmHg) (mean, 95% CI) | 127.31 (16.28) | 126.98 (16.09) | 0.772 |
| Diastolic BP (mmHg) (mean, 95% CI) | 74.61 (8.59) | 75.14 (8.07) | 0.366 |
| HgbA1c (mean, 95% CI) | 6.67 (0.94) | 7.18 (1.30) | 0.041 |
| Random glucose (mg/dL) (mean, 95% CI) | 97.36 (20.52) | 97.51 (25.56) | 0.961 |
| Comorbidities, No. (%) | |||
| Hypertension | 135 (31.0) | 150 (34.5) | 0.312 |
| Myocardial infarction | < 6 | < 6 | 0.722 |
| Diabetes mellitus | 37 (8.5) | 46 (10.6) | 0.356 |
| Heart failure | 8 (1.8) | 10 (2.3) | 0.812 |
| Atrial fibrillation | 12 (2.8) | 11 (2.5) | 1 |
| Cholesterol (mg/dL) (mean, 95% CI) | |||
| High density lipoprotein | 60.62 (17.55) | 59.97 (16.81) | 0.715 |
| Low density lipoprotein | 114.14 (31.91) | 115.77 (34.92) | 0.64 |
| Triglycerides | 141.42 (82.22) | 147.05 (74.20) | 0.489 |
| Total cholesterol | 201.98 (35.41) | 204.74 (39.44) | 0.479 |
| Results | |||
| Percent of TSH values in range, (mean, 95% CI) | 79.3 (76.6-82.1) | 79.1 (76.4-81.7) | 0.905 |
| Visit-to-visit TSH, (SD of TSH) | 1.44 (1.33-1.54) | 1.25 (1.15-1.36) | 0.015 |
| Percent of patients with 100% of TSH values in range, (mean, 95% CI) | 60.0 (55.8-64.1) | 59.8 (55.7-63.9) | 0.951 |
| Number of TSH laboratories obtained per patient over the 3-year study period (mean, IQR) | 3 (3-5) | 4 (3-5) | 0.578 |
BMI = body mass index; BP = blood pressure; HgbA1c = glycosylated hemoglobin; IQR = interquartile range; TSH = thyroid stimulating hormone.