Skip to main content

Table 1 Demographic and clinical characteristics for total knee replacement, SC Medicaid 2014–2017

From: Risk factors and trajectories of opioid use following total knee replacement

Measurea

Level

Chronicb

Non-chronic

Total

p-Value

Unique patientsc

 

1054 (69.9%)

500 (30.1%)

1507

 

Number of total knee surgeries

First surgery

1050 (69.7%)

457 (30.3%)

1507

0.059

Second surgery

99 (62.3%)

60 (37.7%)

159

Age, years

Mean [standard deviation (sd)]

58.7 (9.8)

62.0 (10.1)

59.7 (10.0)

 < 0.0001

Sex

% male

233 (20.3%)

98 (19.0%)

331 (19.9%

0.53

Race/ethnicity

White

420 (36.6%)

176 (34.0%)

596 (35.8%)

0.044

Black

517 (45.0%)

223 (43.1%)

740 (44.4%)

Hispanic

6 (0.5%)

9 (1.7%)

15 (0.9%)

Baseline measures (presurgery periodd)

 Opioid naïvee

0 days

222 (19.3%)

308 (59.6%)

530 (31.8%)

 < 0.0001

 Opioid use during presurgery period

0–49 MME/day

999 (87.0%)

509 (98.5%)

1508 (90.5%)

 < 0.0001

50–89 MME/day

112 (9.8%)

8 (1.6%)

120 (7.2%)

 ≥ 90 MME/day

38 (3.3%%)

0 (0%)

38 (2.3%)

Opioid usef among all patients

 Mean opioid days, mean (std)

Presurgery period

44.0 (42.0)

12.7 (10.6)

34.2 (35.0)

 < 0.0001

Exposure periodg

20.0 (19.5)

10.5 (9.7)

17.1 (10.4)

 < 0.0001

 ≥ 90 days postsurgery

85.4 (81.7)

0

58.9 (66.9)

 < 0.0001

 Mean MME, mean(std)

Presurgery period

21.8 (32.6)

5.9 (12.8)

17.6 (30.0)

 < 0.0001

Exposure period

58.8 (55.6)

27.5 (25.0)

49.1 (51.2)

 < 0.0001

 ≥ 90 days postsurgery

25.1 (41.2)

0

18.5 (42.7)

 < 0.0001

Opioid prescriptions dispensed during exposure period

 Mean opioid days

Mean (std)

21.2 (20.7)

15.2 (14.4)

19.7 (8.5)

 < 0.0001

 Opioid prescription count

Mean (std)

3.1 (1.5)

2.2 (1.3)

2.8 (1.5)

 < 0.0001

 Provider practice specialty

Surgeon

769 (66.9%)

274 (53.0%)

1043 (62.6%)

 < 0.0001

Primary care provider

173 (15.1%)

50 (9.7%)

223 (13.4%)

Concomitant medications dispensed during exposure period (all patients)

 

NSAIDS, APAP

263 (22.9%)

99 (19.2%)

362 (21.7%)

0.089

 

Antidepressants

347 (30.2%)

93 (18.0%)

440 (26.5%)

 < 0.02

 

Gabapentin, pregabalin

229 (19.9%)

51 (9.8%)

280 (16.8%)

 < 0.02

 

Benzodiazepines

218 (19.0%)

40 (7.7%)

258 (15.5%)

 < 0.0001

 

Selected sedatives/hypnoticsh

108 (9.4%)

22 (4.3%)

130 (7.8%

0.0002

 

Muscle relaxants

161 (14.0%)

25 (4.8%)

186 (11.2%)

 < 0.0001

Surgery and process of care variables

Rehospitalization, N (%)

Within 30 days of discharge

21 (1.8%)

5 (1.0%)

26 (1.2%)

0.28

Hospital length of stay

2 or more nights

254 (22.1%)

97 (18.8%)

351 (21.1%)

0.13

1 night or same day

895 (77.9%)

420 (81.2%)

1315 (78.9%)

Number of unique providers visited (claims data)

Mean (std)

1.17 (1.09)

1.00 (0.88)

1.21 (1.43)

0.02

Count of distinct opioid prescribers (pharmacy data)

Mean (std)

1.7 (0.85)

1.0 (0.87)

1.46 (0.92)

 < 0.0001

  1. APAP acetaminophen, MME morphine milligram equivalent, NSAIDS nonsteroidal antiinflammatory drugs
  2. aBecause some patients had multiple surgeries, unless otherwise indicated, all measures are aggregated by surgical procedures rather than by individual patients
  3. bChronic use was defined as any opioid prescription filled ≥ 90 to 270 days after discharge from procedure
  4. cSum of patients with chronic and non-chronic use does not reflect value in total column because some patients with multiple surgeries may appear in both the chronic and non-chronic groups
  5. dThe presurgery period was defined as the 90 days prior to procedure
  6. eOpioid naïve for analyses defined as zero days of opioid use during the presurgery period
  7. fOpioid use was assessed by dispensed opioid prescriptions
  8. gThe exposure period was defined as the 30 days immediately after discharge from procedure
  9. hThis category includes non-benzodiazepine sedative/hypnotics and selected anxiolytics