Table 4.
Estimated Marginal Effects of Medication Possession Ratios, Drug User, Diabetes Knowledge, and Diabetes Care Management on Cumulative 3-Year Medicare Spending
| Marginal Effects (Standard Errors) | ||
|---|---|---|
| Drug Use, Diabetes Knowledge, and Behavioral Variables | Cohort of RAAS Inhibitor Users | Cohort of Statin Users |
| Unadjusted results | ||
| Drug measures | ||
| RAAS-I MPR (scaled 0–10) | −U.S.$38 (237) | — |
| Statin MPR (scaled 0–10) | — | −U.S.$806 (450)* |
| Adjusted results† | ||
| Drug adherence measures | ||
| RAAS-I MPR (scaled 0–10) | −285 (114)** | — |
| Statin MPR (scaled 0–10) | — | −832 (219)*** |
| Drug user variables (yes/no) | ||
| RAAS inhibitors | — | 513 (2,039) |
| Statins | −371 (1,693) | — |
| Older oral antidiabetic drugs‡ | −1,325 (2,181) | −3,947 (2,784) |
| Newer oral antidiabetic drugs§ | −773 (3,304) | −9,571 (2,656)*** |
| Insulin fills | 2,812 (3,354) | 5,212 (3,861) |
| Older and newer oral drug | 2,634 (4,084) | 16,114 (4,985)*** |
| Insulin plus oral drug(s) | 3,279 (5,134) | −1,699 (4,925) |
| Diabetes knowledge | ||
| Good (referent) | ||
| Some | −1,763 (2,093) | −9 (2,372) |
| Poor | −3,532 (2,390) | 5,896 (3,790) |
| Diabetes (DM) management | ||
| DM management class | −2,636 (1,690) | −2,958 (1,902) |
| Tests own blood sugar | 847 (2,224) | 2,408 (2,524) |
| Uses diet to control DM | 1,750 (1,912) | 5,713 (2,092)*** |
| Uses exercise to control DM | −3,582 (1,722)** | −1,622 (2,048) |
| Takes daily aspirin | 3,312 (1,763)* | 1,387 (1,895) |
| Checks for sores on feet | −3,882 (2,345)* | −3,297 (2,816) |
*
p<.1
**
p<.05
***
p<.01.
†
Results adjusted for age, former SSDI status, sex, race, marital status, education, income, region, insurance coverage, self-reported health, BMI, comorbidity, ADLs, HCCs, diabetes ascertainment, and censoring variables.
‡
Includes metformin and sulfonylureas.
§
Includes thiazolidinediones, meglitinides, and α-glucosidase inhibitors.
ADLs, activities of daily living; BMI, body mass index; HCC, hierarchical coexisting condition; MPR, medication possession ratio; RAAS, renin–angiotensin–aldosterone system; SSDI, Social Security Disability Insurance.