Table 2.
Distribution of baseline characteristics according to adherence trajectory among Medicare beneficiaries initiating antihypertensives
| Trajectory group, % | ||||||
|---|---|---|---|---|---|---|
| Immediate drop-off | Rapid drop-off | Gradual drop-off | Partial drop-off | Early drop-off then rebound | Adherent | |
| Covariates | n = 50,797 | n = 22,404 | n = 39,953 | n = 29,429 | n = 28,304 | n = 111,633 |
| Female gender | 59.9 | 57.3 | 58.9 | 59.8 | 61.1 | 60.8 |
| Mean age (std) | 75.3 (7.1) | 75.0 (7.0) | 75.0 (7.0) | 75.1 (7.0) | 75.2 (7.1) | 75.0 (7.1) |
| Race/ethnicity | ||||||
| White | 80.8 | 82.2 | 83.6 | 77.9 | 83.4 | 88.6 |
| African American | 8.4 | 6.8 | 6.9 | 10.4 | 7.6 | 5.2 |
| Hispanic | 4.8 | 4.7 | 3.6 | 5.0 | 3.5 | 1.9 |
| Othera | 6.0 | 6.4 | 5.9 | 6.7 | 5.6 | 4.3 |
| Initiated with combination therapy | 8.7 | 12.1 | 13.6 | 11.8 | 13.5 | 17.7 |
| Average days supply on index date (std) | 27.3 (9.0) | 40.6 (25.9) | 35.1 (21.9) | 29.6 (15.1) | 30.6 (17.5) | 32.6 (19.7) |
| Medication use 14 days prior to index date | ||||||
| 1–2 Meds | 55.0 | 56.0 | 55.6 | 57.0 | 55.3 | 53.5 |
| 3–4 Meds | 30.1 | 29.3 | 28.9 | 29.1 | 29.1 | 29.1 |
| 5 or More meds | 15.0 | 14.7 | 15.5 | 13.9 | 15.6 | 17.3 |
| Insurance gap during baseline | 16.0 | 15.7 | 16.4 | 14.5 | 16.5 | 16.7 |
| Eligible for low-income subsidy | 5.6 | 5.3 | 5.6 | 6.1 | 5.7 | 5.6 |
| Loop diuretic | 9.5 | 9.6 | 10.4 | 9.4 | 10.7 | 11.1 |
| Antiarrhythmic | 5.2 | 4.5 | 4.5 | 4.7 | 4.8 | 4.6 |
| Antidepressantb | 17.4 | 17.1 | 17.7 | 16.5 | 17.8 | 16.8 |
| Antiepileptic | 10.5 | 10.1 | 9.6 | 9.2 | 10.2 | 9.1 |
| Anxiolytic | 4.9 | 4.4 | 4.2 | 4.4 | 4.1 | 3.7 |
| Benzodiazepine | 1.5 | 1.3 | 1.2 | 1.2 | 1.2 | 1.2 |
| Opioid | 37.1 | 33.2 | 33.0 | 34.2 | 34.0 | 30.2 |
| Hypnotic | 8.5 | 8.0 | 7.3 | 7.5 | 7.7 | 6.7 |
| Diabetes | 24.8 | 28.3 | 27.6 | 28.3 | 28.6 | 25.5 |
| Chronic kidney disease | 11.9 | 11.8 | 12.0 | 11.8 | 12.4 | 11.5 |
| Parkinson’s disease | 2.0 | 1.7 | 1.7 | 1.5 | 1.7 | 1.5 |
| Alzheimer’s disease | 3.3 | 2.8 | 3.3 | 2.7 | 3.3 | 3.5 |
| COPD | 19.5 | 17.3 | 17.5 | 17.3 | 17.7 | 16.4 |
| Congestive heart failure | 10.1 | 9.8 | 10.7 | 9.9 | 10.6 | 11.5 |
| Arrhythmia | 20.9 | 20.5 | 20.9 | 18.3 | 20.4 | 23.4 |
| Osteoarthritis | 18.7 | 18.0 | 17.4 | 18.5 | 18.2 | 16.1 |
| Rheumatoid arthritis | 3.8 | 3.5 | 3.5 | 3.8 | 3.5 | 3.1 |
| Stroke | 16.1 | 15.9 | 16.1 | 15.2 | 16.8 | 16.6 |
| Myocardial infarction | 1.8 | 2.0 | 2.4 | 1.5 | 2.1 | 3.8 |
| Hypertension | 66.4 | 73.2 | 77.8 | 74.6 | 79.1 | 79.6 |
| Obesity | 4.6 | 4.8 | 5.0 | 4.8 | 5.3 | 5.0 |
| Fracture history | 9.8 | 8.2 | 8.4 | 8.8 | 8.7 | 7.9 |
| Average frailty predictor index (std)c | 0.11 (0.1) | 0.10 (0.1) | 0.10 (0.1) | 0.10 (0.1) | 0.11 (0.1) | 0.10 (0.1) |
| Home oxygen use | 5.1 | 4.5 | 4.2 | 4.3 | 4.4 | 4.1 |
| Walker or wheelchair use | 4.5 | 4.0 | 3.9 | 4.2 | 4.2 | 3.8 |
| Hospital bed | 1.2 | 0.8 | 1.0 | 1.0 | 1.0 | 0.9 |
| Difficulty walking | 11.4 | 10.6 | 10.5 | 10.4 | 11.0 | 10.3 |
| Vertigo | 15.9 | 14.6 | 13.7 | 14.5 | 14.0 | 12.7 |
| Ambulance transport | 14.8 | 11.8 | 12.6 | 11.7 | 12.9 | 13.7 |
| Cancer screenings | 34.6 | 35.5 | 37.3 | 34.8 | 37.7 | 39.5 |
| Hospital admissions | 25.2 | 21.2 | 21.5 | 19.6 | 21.7 | 23.8 |
| Long stay admissions | 2.1 | 1.5 | 1.6 | 1.5 | 1.8 | 1.8 |
| Short-term hospital stays | 24.3 | 20.6 | 20.8 | 18.8 | 20.8 | 23.0 |
Abbreviations: COPD, chronic obstructive pulmonary disease; Index date, start of antihypertensive therapy; std, standard deviation.
aOther includes Asian, North American Native, and other race/ethnicities.
bAntidepressants include selective serotonin reuptake inhibitors, tricyclics, monoamine oxidase inhibitors, serotonin, and norepinephrine inhibitors.
cHigher scores denote a higher probability of being frail.