Table 1.
Patient and prescriber characteristics and use of gabapentinoids in US ambulatory care settings: 2003 to 2016.
| Overall Weighted Estimate Visits | Gabapentinoids a | Gabapentin a | Pregabalin a | |
|---|---|---|---|---|
| 260.1 Million | 208.9 Million | 53.7 Million | ||
| Patient Characteristics | Weighted. % | Weighted. % | Weighted. % | SMD b |
| ≥65 years | 38.2 | 38.8 | 35.0 | 0.08 |
| Female | 61.9 | 61.7 | 63.0 | 0.03 |
| Race/ethnicity | 0.04 | |||
| White | 85.5 | 85.3 | 86.6 | |
| Non-white c | 14.5 | 14.7 | 13.4 | |
| Current smoker | 16.6 | 16.5 | 16.7 | 0.001 |
| Insurance coverage d | 0.19 | |||
| Governmental | 52.3 | 53.8 | 46.7 | |
| Commercial | 38.2 | 36.5 | 45.5 | |
| Others | 4.7 | 4.9 | 3.8 | |
| Major visit reason due to chronic problems e | 62.6 | 62.3 | 62.3 | 0.01 |
| Concurrent use with | ||||
| Opioids | 32.9 | 31.4 | 38.4 | 0.18 |
| Benzodiazepines | 15.3 | 15.6 | 13.6 | 0.06 |
| Both opioids and benzodiazepines | 6.1 | 5.9 | 6.6 | 0.03 |
| ≥2 chronic conditions d,e | 61.3 | 62.4 | 57.8 | 0.08 |
| Prescriber Characteristics | ||||
| Specialty | 0.21 | |||
| Primary care | 45.8 | 45.8 | 45.1 | |
| Neurology | 8.2 | 8.4 | 8.6 | |
| Surgery | 6.2 | 5.7 | 7.8 | |
| Psychiatry | 4.8 | 5.5 | 1.9 | |
| Others | 35.0 | 34.6 | 36.6 | |
| Geographic region | 0.20 | |||
| Northeast | 15.9 | 16.4 | 14.8 | |
| Midwest | 24.4 | 21.2 | 21.8 | |
| South | 40.6 | 39.0 | 46.9 | |
| West | 22.1 | 23.4 | 16.5 | |
| Metropolitan area | 86.8 | 87.1 | 86.1 | 0.03 |
| Unapproved use f | 96.6 | 98.3 | 89.9 | 0.37 |
Abbreviations: SMD, standardized mean difference. a National estimates of ambulatory visits involving gabapentinoids, gabapentin, and pregabalin accounted for 2.4%, 1.9%, and 0.5% of all adult ambulatory visits, respectively. b SMD > 0.1 was considered as having non-negligible differences. c Racial groups other than White and African American only accounted for 3.0% of all gabapentinoid visits and were combined with non-white. d The percentage of missing data for insurance coverage and major visit reason due to chronic problems was 4.8% and 1.4%, respectively, from 2003 to 2016. The percentage of missing data for the variable of ≥2 chronic conditions was 1.2% from 2005 to 2016. e The number of chronic conditions was available starting in 2005. The weighted proportions were calculated based on the overall gabapentinoid visits from 2005 to 2016 (245.9 million). f An unapproved use was defined as a visit involving gabapentinoids without an FDA-approved indication for gabapentinoids among the first three physician reported diagnoses.