Table 2.
Baseline demographics (included eyes)
| Initial (N = 77,769) |
Non-initial (N = 139,927) |
P value | |
|---|---|---|---|
| Age, years | |||
| Mean (SD) | 65.08 (11.1) | 63.43 (11.6) | < 0.0001 |
| Median (range) | 66 (18–88) | 64 (18–88) | |
| IQR | 58–73 | 56–71 | |
| Age group, n (%) | |||
| 18–39 | 1,783 (2.3) | 4,685 (3.4) | < 0.0001 |
| 40–49 | 4,721 (6.1) | 11,135 (8.0) | |
| 50–59 | 15,537 (20.0) | 31,632 (22.6) | |
| 60–69 | 27,819 (35.8) | 48,933 (35.0) | |
| 70–79 | 20,939 (26.9) | 33,180 (23.7) | |
| 80–89 | 6,970 (9.0) | 10,362 (7.4) | |
| Sex, n (%) | |||
| Male | 39,865 (51.3) | 70,607 (50.5) | 0.0003 |
| Female | 37,904 (48.7) | 69,320 (49.5) | |
| Race, n (%) | |||
| White or Caucasian | 52,754 (67.8) | 87,147 (62.3) | < 0.0001 |
| Black or African American | 10,554 (13.6) | 22,350 (16.0) | |
| Asian | 2,109 (2.7) | 4,130 (3.0) | |
| Other race | 2,413 (3.1) | 5,333 (3.8) | |
| Unknown | 9,126 (11.7) | 19,221 (13.7) | |
| Ethnicity, n (%) | |||
| Hispanic | 11,242 (14.5) | 24,447 (17.5) | < 0.0001 |
| Non-Hispanic | 55,305 (71.1) | 94,917 (67.8) | |
| Unknown | 11,222 (14.4) | 20,563 (14.7) | |
| US census regiona, n (%) | |||
| Midwest | 16,424 (21.1) | 27,110 (19.4) | < 0.0001 |
| North | 12,463 (16.0) | 25,802 (18.4) | |
| South | 33,180 (42.7) | 59,441 (42.5) | |
| West | 14,864 (19.1) | 25,529 (18.2) | |
| Unknown | 838 (1.1) | 2,045 (1.5) | |
| Insurance/payer type, n (%) | |||
| Medicare | 40,916 (52.6) | 70,395 (50.3) | < 0.0001 |
| Medicaid | 5,244 (6.7) | 11,893 (8.5) | |
| Commercial | 24,670 (31.7) | 45,049 (32.2) | |
| Other | 6,939 (8.9) | 12,590 (9.0) | |
| Provider specialty, n (%) | |||
| Retina Specialist | 67,105 (86.3) | 120,453 (86.1) | < 0.0001 |
| Non-Retina Specialist | 2,300 (3.0) | 4,197 (3.0) | |
| General Ophthalmologist | 6,963 (9.0) | 11,831 (8.5) | |
| Unknown | 1,401 (1.8) | 3,446 (2.5) | |
| Length of follow up (years) Mean, SD | 2.87 (1.61) | 2.94 (1.67) | < 0.0001 |
|
Patients with follow up, n (%) Totalb > 0 and ≤ 1 years > 1 and ≤ 2 years > 2 and ≤ 3 years > 3 and ≤ 4 years > 4 and ≤ 5 years > 5 and ≤ 6 years > 6 and ≤ 7 years > 7 years |
61,246 (100) 7,998 (13.1) 13,358 (21.8) 13,522 (22.1) 11,340 (18.5) 7,982 (13.0) 4,455 (7.3) 2,092 (3.4) 499 (0.8) |
105,612 (100) 13,791 (13.1) 22,023 (20.9) 22,454 (21.3) 18,813 (17.8) 14,834 (14.1) 8,525 (8.1) 4,194 (4.0) 978 (978) |
< 0.0001 |
Abbreviations: IQR interquartile range, SD standard deviation, US United States
aMidwest: ND, SD, NE, KS, MO, MN, IA, WI, IL, IN, OH, MI. North: ME, NH, VT, PA, NY, NJ, MA, RI, CT. South: MD, DE, WV, VA, DC, NC, SC, KY, TN, FL, GA, AL, MS, LA, AR, OK, TX. West: NM, AZ, CO, UT, WY, MT, ID, NV, CA, OR, WA, AK, HI
bOne eye per patient is reported for follow up. To define the study period for which healthcare resource utilization would be described, the maximum amount of follow-up time was used. For example, for patients with bilateral eyes affected, healthcare utilization would be assessed from the earliest index date to the latest end of follow-up date, regardless of eye. P values were calculated using Chi-square tests of independence with Yates’s correction for categorical variables, and Welch’s t-tests were used for continuous variables