Table 2.
Adults with major depressive disorder, predicting persistence on antidepressant treatment at six months (n=47,495) a
| Total No. (%) | Proportion persistent % | Baseline prediction model RR (95% CI) e | |
|---|---|---|---|
|
|
|||
| Female | 30,458 (64) | 46 | – |
| Age at antidepressant initiation (years), mean ± SD | 40 ± 13 | ||
| 18 – 24 | 8,187 (17) | 37 | 1.00 (Reference) |
| 25 – 34 | 8,935 (19) | 42 | 1.13 (1.09, 1.18) |
| 35 – 49 | 17,432 (37) | 47 | 1.26 (1.22, 1.30) |
| 50 – 64 | 12,941 (27) | 52 | 1.39 (1.34, 1.44) |
| Index antidepressant class | |||
| SSRI | 40,265 (85) | 45 | 1.00 (Reference) |
| SNRI | 7,230 (15) | 49 | 1.07 (1.04, 1.10) |
| Index dose | |||
| Low initial dose b | 6,710 (14) | 43 | 0.93 (0.90, 0.96) |
| Non-low initial dose | 39,578 (83) | 46 | 1.00 (Reference) |
| Unknown dose | 1,207 (3) | 49 | 1.06 (1.00, 1.12) |
| MDD recurrent episode | 25,765 (54) | 46 | – |
| Depression severity c | |||
| 1 outpatient diagnosis prior year | 13,740 (29) | 46 | 1.00 (Reference) |
| ≥2 outpatient diagnoses prior year | 29,429 (62) | 46 | 1.00 (0.98, 1.02) |
| Non-primary inpatient diagnosis prior year | 1,608 (3) | 39 | 0.94 (0.88, 1.00) |
| Primary inpatient diagnosis 31–360 days prior | 397 (1) | 39 | 0.90 (0.80, 1.02) |
| Primary inpatient diagnosis ≤30 days prior | 2,321 (5) | 37 | 0.91 (0.86, 0.97) |
| Suicide attempt | 511 (1) | 37 | – |
| Personality disorder | 639 (1) | 41 | – |
| ADHD | 1,497 (3) | 42 | – |
| Schizophrenia | 272 (1) | 43 | – |
| Anxiety | 13,105 (28) | 46 | – |
| Substance use disorder | |||
| No substance use disorder diagnosis | 41,455 (87) | 47 | 1.00 (Reference) |
| Substance use disorder diagnosis, no hospitalization | 5,557 (12) | 37 | 0.84 (0.81, 0.87) |
| Substance use disorder related hospitalization | 483 (1) | 31 | 0.70 (0.61, 0.81) |
| Non-psychiatric related hospitalization (1+) | 5,320 (11) | 42 | – |
| Outpatient visits, mean ± SD | 19 ± 18 | ||
| <5 | 7,103 (15) | 44 | 1.00 (Reference) |
| 5 – 9 | 10,498 (22) | 45 | 1.02 (0.99, 1.06) |
| 10 – 19 | 14,058 (30) | 45 | 1.03 (1.00, 1.07) |
| 20 – 39 | 10,887 (23) | 46 | 1.07 (1.03, 1.11) |
| ≥40 | 4,949 (10) | 47 | 1.08 (1.04, 1.13) |
| Generic prescription drugs, mean ± SD | 6 ± 5 | ||
| Antidepressant only | 4,835 (10) | 47 | 1.00 (Reference) |
| 2 – 3 | 11,578 (24) | 46 | 0.98 (0.95, 1.02) |
| 4 – 5 | 9,472 (20) | 47 | 1.00 (0.97, 1.04) |
| 6 – 9 | 12,227 (26) | 45 | 0.97 (0.94, 1.01) |
| ≥10 | 9,383 (20) | 43 | 0.93 (0.89, 0.97) |
| High-potency prescription opiate usage | 905 (2) | 39 | 0.92 (0.84, 0.99) |
| Mid-potency prescription opiate usage | 14,088 (30) | 41 | 0.88 (0.86, 0.91) |
| Cancer, malignant neoplasm | 1,769 (4) | 50 | – |
| Arthritis | 422 (1) | 48 | – |
| Osteoarthritis | 2,914 (6) | 48 | – |
| Postural hypotension | 129 (0) | 51 | – |
| Congestive heart failure | 561 (1) | 44 | – |
| Cardiac arrhythmia | 2,064 (4) | 45 | – |
| Urinary incontinence | 445 (1) | 44 | – |
| Diabetes | 3,595 (8) | 47 | – |
| Cerebrovascular disease | 1,071 (2) | 45 | – |
| Gait or balance disorder | 575 (1) | 48 | – |
| Cluster headaches/migraines | 2,320 (5) | 43 | – |
| Seizures | 473 (1) | 45 | – |
| Osteoporosis | 771 (2) | 48 | – |
| Provider specialty d | |||
| Psychiatry | 13,836 (29) | 47 | 1.00 (Reference) |
| Psychology | 2,842 (6) | 45 | 0.95 (0.90, 0.99) |
| General, family practice; pediatrics | 12,163 (26) | 47 | 1.02 (0.99, 1.05) |
| Internal medicine | 4,501 (9) | 47 | 0.99 (0.95, 1.02) |
| Other | 10,666 (22) | 42 | 0.92 (0.89, 0.94) |
| Unknown | 3,487 (7) | 43 | 0.94 (0.91, 0.98) |
| Copayment for index prescription, mean ± SD | 17 ± 22 | ||
| Low copayment (<$24) | 35,505 (75) | 46 | – |
| High copayment ($24+) | 11,990 (25) | 45 | – |
SD (standard deviation), RR (risk ratio), CI (confidence interval), SSRI (selective serotonin reuptake inhibitors), SNRI (serotonin-norepinephrine reuptake inhibitor), ADHD (attention deficit hyperactivity disorder)
Symbol ‘ – ‘ signifies variable did not end up in the baseline prediction model
Comorbidity definitions are based on diagnostic codes recorded in the prior year; the prevalence of some conditions may be underestimated if the patient did not receive a diagnostic code in that year period.
Persistent at six-months defined as treatment for 180 days without gaps based on days supply, with 30 day grace period; all individuals were required to be continually enrolled for at least 180 days after antidepressant initiation
Low dose=18–64 years: <20mg/day (mg/d) Citalopram, Fluoxetine, and Paroxetine immediate release, <25mg/d Paroxetine controlled release, <50mg/d Sertraline, <60mg/d Duloxetine, and <75mg/d Venlafaxine
Depression diagnoses included in severity measure: ICD-9-CM: 296.2x, 296.3x, 298.0x, 300.4x, 309.0x, 309.1x, 311.x, 293.83, 296.90, 309.28
Provider specialty associated with the index antidepressant prescription; ‘Unknown’ included missing, not available, and unknown
RR>1.00 signifies increased likelihood of persistence