Table 1.
Characteristics of Patients Initiating a Chronic Disease Medication During 2007–2014 Stratified by Time to Prescription Fill
| Covariate | Overall (N = 32,586) | Fill in 0–7 days | Fill in 8–30 days | Late filling or no fills |
|---|---|---|---|---|
| (N = 24,305) | (N = 2014) | (N = 6267) | ||
| Demographics | ||||
| Age, mean (SD) | 74.7 (7.4) | 74.9 (7.4) | 74.1 (7.4) | 74.4 (7.4) |
| Female | 62.6% | 63.1% | 63.8% | 60.3% |
| Race | ||||
| Asian | 2.1% | 2.2% | 2.0% | 1.8% |
| Black | 8.1% | 8.3% | 8.7% | 7.1% |
| Hispanic | 4.9% | 5.5% | 4.1% | 3.1% |
| Other | 3.0% | 3.2% | 2.9% | 2.7% |
| Unknown | 0.9% | 0.9% | 0.5% | 0.7% |
| White | 81.0% | 80.0% | 81.9% | 84.7% |
| Veteran status | ||||
| Yes | 11.3% | 11.0% | 11.5% | 12.4% |
| No | 69.4% | 70.0% | 67.0% | 67.7% |
| Unknown/not determined | 19.3% | 19.0% | 21.5% | 19.9% |
| Percent high school education in zip code | 89.2 (8.4) | 89.0 (8.5) | 89.6 (8.1) | 89.7 (8.2) |
| Percent black in zip code | 8.4 (13.9) | 8.6 (14.1) | 8.4 (14.1) | 7.6 (13.2) |
| Median household income in zip code | $77,487 ($31,414) | $77,082 ($31,345) | $79,281 ($32,673) | $78,483 ($31,232) |
| Primary language | ||||
| English | 83.8% | 2.6% | 86.6% | 87.6% |
| Non-English | 15.3% | 16.6% | 12.4% | 11.4% |
| Unavailable | 0.9% | 0.8% | 0.9% | 1.1% |
| Relationship status* | ||||
| In a relationship | 46.3% | 45.0% | 47.4% | 50.9% |
| Not in a relationship | 47.9% | 49.0% | 47.0% | 43.8% |
| Unknown | 5.8% | 5.9% | 5.6% | 5.3% |
| Comorbid conditions | ||||
| Atrial fibrillation | 5.1% | 5.2% | 5.1% | 4.8% |
| Alcohol abuse | 0.9% | 0.8% | 1.2% | 0.9% |
| Allergic reaction | 2.4% | 2.4% | 2.3% | 2.5% |
| Coronary artery disease | 7.7% | 7.9% | 6.1% | 7.6% |
| Congestive heart failure | 5.3% | 5.4% | 4.1% | 5.4% |
| Cancer | 36.8% | 36.3% | 36.5% | 38.8% |
| Dementia | 3.3% | 3.3% | 2.7% | 3.1% |
| Depression | 16.1% | 16.6% | 15.2% | 14.5% |
| Diabetes | 29.2% | 29.6% | 28.3% | 28.1% |
| Asthma | 26.2% | 25.6% | 26.6% | 28.5% |
| Hyperlipidemia | 63.2% | 63.0% | 65.4% | 63.4% |
| Hypertension | 79.3% | 79.8% | 78.5% | 77.5% |
| Osteoporosis | 20.9% | 20.8% | 20.8% | 21.3% |
| Prior myocardial infarction | 0.8% | 0.9% | 0.5% | 0.7% |
| Revascularization | 2.5% | 2.6% | 1.6% | 2.4% |
| Stroke | 1.0% | 1.0% | 0.9% | 1.0% |
| Acute renal failure or end stage renal disease | 1.6% | 1.7% | 1.1% | 1.6% |
| Combined comorbidity score | 2.7 | 2.7 | 2.6 | 2.7 |
| Laboratory values and vitals | ||||
| Body mass index | ||||
| < 18.5 | 0.9% | 0.9% | 0.8% | 1.0% |
| ≥ 18.5 and < 24.9 | 15.9% | 15.8% | 16.1% | 16.2% |
| ≥ 25 and < 29.9 | 23.5% | 23.4% | 24.1% | 23.6% |
| ≥ 30 | 24.0% | 24.0% | 24.8% | 23.6% |
| No measurements in data | 35.7% | 35.9% | 34.1% | 35.6% |
| Average HbA1c level, mean (SD)† | 6.8 (1.4) | 6.8 (1.4) | 6.9 (1.6) | 6.7 (1.3) |
| Average LDL level, mean (SD)‡ | 100.4 (38.5) | 100.9 (38.9) | 102.4 (38.2) | 97.7 (36.6) |
| Average systolic blood pressure, mean (SD)§ | 134.1 (21.2) | 134.7 (22.0) | 131.7 (18.4) | 132.1 (18.0) |
| Resource utilization | ||||
| Emergency department visits, mean (SD) | 0.7 (2.6) | 0.7 (2.5) | 0.7 (2.6) | 0.8 (2.8) |
| Hospitalizations, mean (SD) | 0.3 (0.8) | 0.3 (0.8) | 0.3 (0.8) | 0.3 (0.8) |
| Unique physicians, mean (SD) | 3.6 (2.5) | 3.6 (2.5) | 3.5 (2.3) | 3.6 (2.5) |
| Physician office visits, mean (SD) | 5.9 (4.7) | 6.0 (4.7) | 5.4 (4.2) | 5.8 (4.7) |
| Outpatient encounter 7 days before or after index order | 63.2% | 62.3% | 67.8% | 65.3% |
| Benefit characteristics | ||||
| At least 1 month receiving Medicare Part D low-income subsidy | 34.1% | 36.9% | 28.9% | 24.9% |
| Switch in Part D plan | 7.9% | 7.9% | 9.6% | 7.3% |
| Copayment amount corresponding to outpatient encounter 7 days before or after index order (missing if no visit), median (IQR) | $0 ($0) | $0 ($0) | $0 ($0) | $0 ($0) |
| Index order characteristics | ||||
| Quantity ≤ 30 | 56.2% | 58.1% | 47.0% | 52.1% |
| Medication frequency | ||||
| < Once daily | 4.3% | 4.1% | 5.2% | 4.7% |
| Once daily | 70.3% | 71.5% | 70.2% | 65.5% |
| > Once daily | 23.8% | 22.7% | 22.8% | 28.5% |
| Other | 1.6% | 1.6% | 1.7% | 1.3% |
| Number of refills, mean (SD) | 4.2 (3.1) | 4.3 (3.2) | 3.8 (2.7) | 4.1 (3.1) |
| Number of refills | ||||
| 0 | 5.9% | 5.9% | 5.1% | 6.4% |
| 1 | 8.2% | 8.6% | 6.4% | 7.2% |
| 2 | 4.1% | 4.4% | 2.4% | 3.5% |
| 3 | 44.5% | 42.4% | 57.9% | 48.4% |
| 4 | 4.9% | 4.9% | 4.9% | 4.9% |
| 5 | 11.9% | 12.4% | 9.1% | 10.7% |
| 6 | 6.6% | 6.9% | 4.9% | 5.8% |
| 7 | 0.0% | 0.0% | 0.0% | 0.0% |
| 8 | 0.1% | 0.1% | 0.1% | 0.1% |
| 9 | 0.1% | 0.1% | 0.2% | 0.1% |
| 10 | 0.1% | 0.1% | 0.0% | 0.1% |
| 11 | 11.4% | 12.0% | 7.7% | 10.5% |
| 12 | 2.1% | 2.1% | 1.5% | 2.4% |
| > 12 | 0.1% | 0.1% | 0.1% | 0.1% |
| Discontinuation order for same generic as index during baseline | 0.0% | 0.0% | 0.0% | 0.0% |
| Reconciliation order for same generic as index during baseline | 3.0% | 2.7% | 2.6% | 3.8% |
| Dispense as written on index order | 0.9% | 0.5% | 1.4% | 2.0% |
| Prescriber is a primary care physician | 55.5% | 56.3% | 55.4% | 52.8% |
| Prescriber is a specialist physician | 42.2% | 42.5% | 42.0% | 41.2% |
| Adherence predictors | ||||
| Current medications, mean (SD) | 4.9 (3.2) | 5.4 (3.1) | 3.6 (2.9) | 3.3 (3.0) |
| Unique medications during baseline, mean (SD) | 8.1 (4.8) | 8.6 (4.7) | 6.7 (4.4) | 6.3 (4.8) |
| Fills in baseline period, mean (SD) | 18.3 (14.8) | 19.6 (15.0) | 14.3 (12.4) | 14.3 (13.9) |
| Out-of-pocket amount, median (IQR) | $122 ($304) | $118 ($302) | $118 ($290) | $142 ($313) |
| Average out-of-pocket amount per fill, median (IQR) | $11 ($21) | $10 ($20) | $12 ($24) | $14 ($24) |
| New to therapeutic area | 96.7% | 97.0% | 97.0% | 95.7% |
| Day of the week of index order date | ||||
| Sunday | 0.5% | 0.5% | 0.4% | 0.6% |
| Monday | 22.4% | 22.6% | 22.3% | 21.8% |
| Tuesday | 21.5% | 21.2% | 21.9% | 22.4% |
| Wednesday | 19.0% | 18.8% | 20.3% | 19.7% |
| Thursday | 18.9% | 19.1% | 17.8% | 18.1% |
| Friday | 16.8% | 16.9% | 16.7% | 16.4% |
| Saturday | 0.9% | 0.9% | 0.5% | 0.9% |
| Mammogram or PSA test | 27.0% | 26.7% | 29.5% | 27.7% |
*Relationship status is defined as being “in a relationship” if marital status is defined in EHR as either “married” or “partner,” and not as “unknown” or “declined.” Otherwise, relationship status is defined as “not in a relationship”
†Serum glycated hemoglobin (HbA1c) measurements identify average blood plasma glucose concentrations over a period of 2–3 months; in our data, HbA1c test results do not include patients with missing values
‡Low-density lipoprotein (LDL) measurements provide an estimate of the amount of cholesterol in blood which drives progression of atherosclerosis. In our data, LDL test results do not include patients with missing values
§In our data, systolic blood pressure results do not include patients with missing values