Table 1.
Baseline patient characteristics before and after matching
| Patient characteristics | Unmatched |
Matched |
||||
|---|---|---|---|---|---|---|
| AD |
Controls |
P | AD |
Controls |
P | |
| (N = 21,222) | (N = 151,792) | (N = 19,679) | (N = 19,679) | |||
| Age, mean (SD) | 83.59 (6.78) | 77.28 (6.19) | ** | 83.34 (6.67) | 83.47 (6.97) | |
| Male (%) | 33.5% | 43.2% | ** | 34.0% | 33.9% | |
| Race (%) | - | - | ** | - | - | |
| White | 87.9% | 88.9% | 87.9% | 87.8% | ||
| Black | 7.3% | 6.3% | 7.2% | 7.1% | ||
| Asian | 1.5% | 1.6% | 1.5% | 1.6% | ||
| Hispanic | 2.1% | 1.2% | 2.1% | 2.1% | ||
| North American Native | 0.3% | 0.4% | 0.3% | 0.3% | ||
| US Census region (%) | - | - | ** | - | - | |
| West | 15.0% | 17.8% | 15.2% | 15.3% | ||
| Midwest | 23.7% | 24.1% | 23.7% | 23.8% | ||
| Northeast | 18.2% | 18.3% | 17.9% | 17.8% | ||
| South | 42.7% | 39.5% | 42.7% | 42.8% | ||
| Year of index date (%) | - | - | ** | - | - | |
| 2012 | 38.9% | 33.7% | 38.8% | 38.7% | ||
| 2013 | 35.2% | 32.4% | 35.3% | 35.3% | ||
| 2014 | 25.9% | 33.9% | 26.0% | 26.0% | ||
| Patients with ≥1 CCI components | ||||||
| Chronic pulmonary disease | 18.3% | 15.3% | ** | 18.0% | 18.1% | |
| Peripheral vascular disease | 17.9% | 10.0% | ** | 16.7% | 16.5% | |
| Cerebrovascular disease | 16.8% | 7.5% | ** | 15.2% | 15.1% | |
| Mild to moderate diabetes | 16.4% | 16.6% | 16.4% | 16.8% | ||
| Congestive heart failure | 14.2% | 8.4% | ** | 13.5% | 13.5% | |
| Any malignancy including lymphoma and leukemia | 11.5% | 11.9% | 11.7% | 12.0% | ||
| Diabetes with chronic complications | 10.4% | 7.4% | ** | 10.0% | 10.0% | |
| Renal disease | 9.6% | 6.3% | ** | 9.2% | 9.3% | |
| Myocardial infarction | 4.9% | 3.4% | ** | 4.6% | 4.5% | |
| Rheumatologic disease | 3.5% | 2.9% | ** | 3.4% | 3.4% | |
| Patients with ≥1 additional comorbidities | ||||||
| Hyperlipidemia | 57.1% | 58.3% | ** | 57.1% | 57.8% | |
| Depression | 14.3% | 5.9% | ** | 12.7% | 12.2% | |
| Psychosis | 3.3% | 0.4% | ** | 2.1% | 1.7% | ** |
| Bipolar disorder | 1.1% | 0.4% | ** | 0.9% | 0.8% | |
| Baseline resource use (patients with ≥1 visit [%]) | ||||||
| Emergency department visits | 35.8% | 21.3% | ** | 33.8% | 33.1% | |
| Inpatient visits | 19.6% | 11.9% | ** | 17.9% | 17.2% | |
| Outpatient/physician office visits | 97.0% | 96.4% | ** | 96.8% | 96.9% | |
| Skilled nursing facility visits | 6.1% | 1.6% | ** | 4.6% | 4.1% | * |
| Home health-care visits | 13.2% | 4.6% | ** | 11.4% | 10.6% | ** |
| Baseline costs, mean (SD) | $9597 ($18,379) | $6051 ($13,395) | ** | $8711 ($17,074) | $8457 ($17,254) | ** |
Abbreviations: AD, Alzheimer's disease; CCI, Charlson Comorbidity Index; SD, standard deviation.
**P < .01 and *P < .05, evaluated before matching using chi-square tests for proportions and Wilcoxon rank-sum tests for continuous measures and evaluated after matching using McNemar's tests for proportions and Wilcoxon sign-rank test for continuous measures.