Table 1. Selected Cohort Characteristics Before and After Propensity Score Matchinga.
| Characteristic | Before Propensity Score Matching | SMD | After Propensity Score Matchingb | SMD | ||
|---|---|---|---|---|---|---|
| Intensified (n = 2074) | Not Intensified (n = 12 841) | Intensified (n = 2028) | Not Intensified (n = 2028) | |||
| Age, mean (SD), y | 76.8 (8.4) | 76.6 (8.6) | −0.02 | 76.8 (8.4) | 76.6 (8.7) | −0.02 |
| Male sex | 2022 (97.5) | 12 515 (97.5) | 0 | 1977 (97.5) | 1984 (97.8) | 0.02 |
| Race/ethnicity | ||||||
| White | 1450 (69.9) | 10036 (78.2) | 0.20 | 1428 (70.4) | 1432 (70.6) | 0.03 |
| Black | 507 (24.4) | 2192 (17.1) | 487 (24) | 482 (23.8) | ||
| Hispanic | 55 (2.7) | 222 (1.7) | 52 (2.6) | 45 (2.2) | ||
| Other | 62 (3.0) | 391 (3.0) | 61 (3.0) | 69 (3.4) | ||
| Preadmission clinical characteristics, mean (SD)c | ||||||
| BMI | 27.9 (6.7) | 27.6 (6.5) | −0.05 | 27.9 (6.7) | 28.1 (6.7) | 0.02 |
| Pulse, beats/mind | 73.6 (12.7) | 74.6 (12.5) | 0.08 | 73.6 (12.7) | 73.9 (12.5) | 0.02 |
| SBP, mm Hgd | 138.6 (19.1) | 132.3 (17.1) | −0.34 | 138.3 (18.9) | 137.9 (18.9) | −0.02 |
| Characteristics of index hospitalization | ||||||
| Length of stay, mean (SD), d | 6.8 (7.3) | 5.4 (6.7) | −0.2 | 6.7 (7.1) | 7.1 (11.6) | 0.04 |
| Inpatient SBPc | ||||||
| ≥3 Readings <90 mm Hg | 45 (2.2) | 419 (3.3) | 0.07 | 44 (2.2) | 42 (2.1) | 0.01 |
| ≥3 Readings ≥160 mm Hg | 719 (34.7) | 2041 (15.9) | 0.44 | 711 (35.1) | 760 (37.5) | −0.06 |
| ≥3 Readings ≥180 mm Hg | 349 (16.8) | 428 (3.3) | 0.46 | 311 (15.3) | 278 (13.7) | 0.06 |
| Discharge diagnosis | ||||||
| Pneumonia | 1045 (50.4) | 6681 (52) | 0.05 | 1027 (50.6) | 1019 (50.2) | 0.01 |
| Urinary tract infection | 790 (38.1) | 4849 (37.8) | 771 (38) | 773 (38.1) | ||
| Venous thromboembolism | 239 (11.5) | 1311 (10.2) | 230 (11.3) | 236 (11.6) | ||
| Laboratory values at discharge, mean (SD)c,e | ||||||
| Sodium level, mEq/L | 138.2 (3.5) | 138.1 (3.5) | −0.01 | 138.2 (3.5) | 138.2 (3.7) | 0.02 |
| Potassium level, mEq/L | 4.1 (0.5) | 4.1 (0.5) | −0.06 | 4.1 (0.5) | 4.1 (0.5) | |
| Estimated glomerular filtration rate, mL/min per 1.73 m2 | 66.3 (32.1) | 71.2 (31.8) | 0.16 | 66.5 (32.1) | 66.8 (32.2) | 0.01 |
| Health care use in year preceding hospitalization | ||||||
| Any Medicare use | 565 (27.2) | 3603 (28.1) | 0.02 | 557 (27.5) | 569 (28.1) | 0.01 |
| ≥3 ED visits | 392 (18.9) | 2555 (19.9) | 0.03 | 386 (19) | 383 (18.9) | 0.01 |
| >3 Hospitalizations | 571 (27.5) | 3651 (28.4) | 0.05 | 562 (27.7) | 552 (27.2) | 0.06 |
| Serious fall event | 94 (4.5) | 569 (4.4) | 0 | 93 (4.6) | 89 (4.4) | 0.01 |
| Admission antihypertensive use and adherencef | ||||||
| 0 Antihypertensives | 526 (25.4) | 3077 (24) | 0.19 | 501 (24.7) | 508 (25) | 0.05 |
| 1 Antihypertensive, PDC≤80% | 270 (13) | 1289 (10) | 261 (12.9) | 278 (13.7) | ||
| 1 Antihypertensive, PDC>80% | 282 (13.6) | 2255 (17.6) | 281 (13.9) | 294 (14.5) | ||
| 2 Antihypertensivess, PDC≤80% | 221 (10.7) | 1032 (8) | 215 (10.6) | 207 (10.2) | ||
| 2 Antihypertensive, PDC>80% | 327 (15.8) | 2378 (18.5) | 324 (16) | 302 (14.9) | ||
| ≥3 Antihypertensives, PDC≤80% | 138 (6.7) | 668 (5.2) | 136 (6.7) | 140 (6.9) | ||
| ≥3 Antihypertensives, PDC>80% | 310 (14.9) | 2142 (16.7) | 310 (15.3) | 299 (14.7) | ||
| Medication classes used at hospital admissiong | ||||||
| ≥8 Admission medications (polypharmacy) | 914 (44.1) | 6387 (49.7) | 0.11 | 910 (44.9) | 921 (45.4) | 0.01 |
| Angiotensin-converting enzyme inhibitors | 656 (31.6) | 4302 (33.5) | 0.04 | 650 (32.1) | 648 (32) | 0 |
| Angiotensin II inhibitors | 175 (8.4) | 1121 (8.7) | 0.01 | 174 (8.6) | 167 (8.2) | 0.01 |
| β-Blockers | 883 (42.6) | 5481 (42.7) | 0 | 873 (43) | 854 (42.1) | 0.02 |
| Calcium channel blockers | 587 (28.3) | 3759 (29.3) | 0.02 | 579 (28.6) | 584 (28.8) | 0.01 |
| Nonloop diuretics | 423 (20.4) | 2528 (19.7) | 0.02 | 416 (20.5) | 415 (20.5) | 0 |
| Other antihypertensives | 230 (11.1) | 1046 (8.1) | 0.10 | 224 (11) | 205 (10.1) | 0.03 |
| Anticoagulants | 96 (4.6) | 598 (4.7) | 0 | 93 (4.6) | 89 (4.4) | 0.01 |
| Platelet aggregation inhibitors | 201 (9.7) | 1206 (9.4) | 0.01 | 198 (9.8) | 198 (9.8) | 0 |
| Opioid analgesics | 467 (22.5) | 2915 (22.7) | 0 | 455 (22.4) | 472 (23.3) | 0.02 |
| Sedatives and hypnotics | 242 (11.7) | 1693 (13.2) | 0.05 | 239 (11.8) | 235 (11.6) | 0.01 |
| Insulin | 400 (19.3) | 2695 (21) | 0.04 | 394 (19.4) | 433 (21.4) | 0.05 |
| Selected comorbiditiesh | ||||||
| Heart failure | 715 (34.5) | 3272 (25.5) | 0.20 | 691 (34.1) | 729 (35.9) | 0.04 |
| Acute myocardial infarction | 116 (5.6) | 610 (4.8) | 0.04 | 112 (5.5) | 102 (5) | 0.02 |
| Coronary artery disease | 895 (43.2) | 5239 (40.8) | 0.05 | 880 (43.4) | 890 (43.9) | 0.01 |
| Valvular heart disease | 263 (12.7) | 1508 (11.7) | 0.03 | 262 (12.9) | 247 (12.2) | 0.02 |
| Arrhythmias | 666 (32.1) | 4225 (32.9) | 0.02 | 649 (32) | 632 (31.2) | 0.02 |
| Chronic obstructive pulmonary disease or asthma | 1021 (49.2) | 6695 (52.1) | 0.06 | 1006 (49.6) | 1028 (50.7) | 0.02 |
| Renal disorders | 1513 (73) | 8862 (69) | 0.09 | 1476 (72.8) | 1479 (72.9) | 0 |
| Diabetes | 1167 (56.3) | 6661 (51.9) | 0.09 | 1135 (56) | 1166 (57.5) | 0.03 |
| Hip fracture | 36 (1.7) | 276 (2.1) | 0.03 | 36 (1.8) | 42 (2.1) | 0.02 |
Abbreviations: BMI, body mass index (calculated as weight in kilograms divided by height in meters squared); ED, emergency department; PDC, proportion of days covered; SBP, systolic blood pressure; SMD, standardized mean difference.
SI conversion factor: To convert sodium and potassium to millimoles per liter, multiply by 1.
Data are presented as number (percentage) of patients unless otherwise indicated. Selected covariates are presented; a full list of covariates included in propensity scoring are given in eTable 3 in the Supplement.
Patients who were discharged with intensified antihypertensive regimens were matched with patients who were discharged without antihypertensive intensifications based on 1:1 propensity score matching without replacement. Matching was performed using a caliper width of 0.2 times the pooled SD of the logit of the propensity scores for the cohort. Balance between the groups was assessed before and after matching by comparing SMDs for each variable for which a difference of less than 0.10 was considered to indicate adequate balance.
Missing data were as follows: income (n = 6), BMI (n = 960), outpatient blood pressure (n = 425), outpatient pulse (n = 534), inpatient blood pressure (n = 167), inpatient pulse (n = 174), hemoglobin (n = 1170), potassium (n = 586), sodium (n = 534), blood urea nitrogen (n = 839), carbon dioxide (n = 735), and platelets (n = 866).
Prehospitalization vital sign data were measured as the median of the 3 most recent ambulatory recordings before index hospitalization, collected in the year before hospitalization and excluding the week immediately preceding hospitalization.
Laboratory data collected from day of index hospitalization discharge or during index hospitalization up to 2 days before day of discharge.
Adherence calculated from electronic pharmacy dispensing data as the PDC for each admission antihypertensive regimen in the year before index hospital admission. A threshold of 80% is a commonly used criterion to determine clinically significant nonadherence. To account for patients taking multiple antihypertensives at hospital admission, a composite PDC was calculated as the mean of each antihypertensive PDC because individual antihypertensive PDCs were highly collinear within patients.
All medications classified using Veterans Affairs drug class coding. Combination medications were split into component parts. Topical, inhaled, otic, and optic medications were excluded.
Comorbidities include both secondary discharge diagnoses from index hospitalization and preadmission diagnoses from the year preceding index hospitalization.