Table 3.
Mean annual costs (in 2012 dollars) over follow-up by intervention assignment for subgroups of participants based on baseline characteristics
| Subgroup | DSE | ILI | Difference (95% CI) | DSE vs. ILI P value† | Interaction P value† |
|---|---|---|---|---|---|
| Age | |||||
| 45–54 years | |||||
| Hospitalization | 1,674 (190) | 1,876 (184) | −203 (−721 to 316) | 0.44 | 0.14 |
| Outpatient | 1,902 (80) | 1,928 (78) | −26 (−246 to 193) | 0.81 | 0.85 |
| Medication | 3,439 (87) | 3,372 (84) | 67 (−170 to 305) | 0.58 | 0.13 |
| Total | 7,014 (263) | 7,176 (255) | −162 (−879 to 556) | 0.66 | 0.09 |
| 55–64 years | |||||
| Hospitalization | 2,713 (129) | 2,355 (128) | 358 (2 to 713) | 0.05 | — |
| Outpatient | 2,313 (54) | 2,272 (54) | 41 (−109 to 191) | 0.59 | — |
| Medication | 3,892 (59) | 3,560 (58) | 332 (170 to 495) | <0.0001 | — |
| Total | 8,918 (178) | 8,187 (177) | 731 (239 to 1,223) | 0.004 | — |
| 65–76 years | |||||
| Hospitalization | 4,321 (208) | 3,828 (218) | 493 (−97 to 1,084) | 0.10 | — |
| Outpatient | 2,954 (88) | 2,973 (92) | −19 (−269 to 230) | 0.88 | — |
| Medication | 3,911 (95) | 3,521 (100) | 390 (120 to 660) | 0.005 | — |
| Total | 11,186 (288) | 10,322 (302) | 864 (47 to 1,681) | 0.04 | — |
| BMI | |||||
| 25–29.9 kg/m2 | |||||
| Hospitalization | 2,125 (254) | 2,250 (240) | −125 (−810 to 561) | 0.72 | 0.36 |
| Outpatient | 2,085 (103) | 2,219 (97) | −134 (−424 to 156) | 0.36 | 0.43 |
| Medication | 3,476 (115) | 3,084 (109) | 392 (82 to 702) | 0.01 | 0.72 |
| Total | 7,686 (352) | 7,552 (333) | 133 (−818 to 1,084) | 0.78 | 0.58 |
| 30.0–39.9 kg/m2 | |||||
| Hospitalization | 2,864 (121) | 2,453 (122) | 411 (74 to 748) | 0.02 | — |
| Outpatient | 2,333 (51) | 2,296 (51) | 38 (−105 to 180) | 0.60 | — |
| Medication | 3,823 (55) | 3,574 (55) | 249 (97 to 401) | 0.001 | — |
| Total | 9,021 (168) | 8,322 (169) | 698 (231 to 1,165) | 0.003 | — |
| >40.0 kg/m2 | |||||
| Hospitalization | 3,001 (202) | 2,829 (201) | 172 (−387 to 731) | 0.55 | — |
| Outpatient | 2,537 (89) | 2,425 (88) | 112 (−134 to 358) | 0.37 | — |
| Medication | 3,867 (91) | 3,603 (91) | 264 (11 to 516) | 0.04 | — |
| Total | 9,405 (281) | 8,857 (279) | 548 (−228 to 1,323) | 0.17 | — |
| Sex | |||||
| Female | |||||
| Hospitalization | 2,311 (123) | 2,221 (123) | 90 (−252 to 432) | 0.60 | 0.08 |
| Outpatient | 2,293 (52) | 2,256 (52) | 37 (−108 to 182) | 0.62 | 0.90 |
| Medication | 3,651 (56) | 3,385 (56) | 266 (111 to 421) | 0.001 | 0.76 |
| Total | 8,255 (171) | 7,862 (171) | 393 (−82 to 867) | 0.10 | 0.18 |
| Male | |||||
| Hospitalization | 3,510 (151) | 2,931 (151) | 579 (160 to 998) | 0.007 | — |
| Outpatient | 2,420 (64) | 2,398 (64) | 23 (−155 to 201) | 0.80 | — |
| Medication | 3,984 (69) | 3,679 (68) | 305 (115 to 495) | 0.002 | — |
| Total | 9,914 (210) | 9,008 (209) | 906 (325 to 1,487) | 0.002 | — |
| History of cardiovascular disease | |||||
| No | |||||
| Hospitalization | 2,407 (101) | 2,082 (101) | 325 (46 to 604) | 0.02 | 0.71 |
| Outpatient | 2,295 (43) | 2,162 (43) | 133 (13 to 252) | 0.03 | <0.0001 |
| Medication | 3,667 (46) | 3,324 (46) | 343 (216 to 470) | <0.0001 | 0.02 |
| Total | 8,369 (139) | 7,568 (139) | 801 (417 to 1,185) | <0.0001 | 0.02 |
| Yes | |||||
| Hospitalization | 5,373 (261) | 5,191 (253) | 181 (−533 to 895) | 0.62 | — |
| Outpatient | 2,674 (112) | 3,266 (109) | −592 (−889 to −286) | 0.0002 | — |
| Medication | 4,569 (119) | 4,635 (116) | −67 (−392 to 259) | 0.69 | — |
| Total | 12,615 (360) | 13,093 (349) | −478 (−1,461 to 505) | 0.34 | — |
| Race/ethnicity | |||||
| African American | |||||
| Hospitalization | 2,118 (242) | 2,590 (241) | −473 (−1,142 to 197) | 0.17 | 0.08 |
| Outpatient | 2,090 (101) | 2,278 (101) | −189 (−469 to 91) | 0.19 | 0.32 |
| Medication | 3,437 (107) | 3,129 (107) | 308 (11 to 605) | 0.04 | 0.95 |
| Total | 7,644 (332) | 7,998 (331) | −353 (−1,271 to 565) | 0.45 | 0.13 |
| American Indian | |||||
| Hospitalization | 2,188 (431) | 1,956 (424) | 232 (−953 to 1,417) | 0.70 | — |
| Outpatient | 1,479 (180) | 1,607 (177) | −128 (−624 to 367) | 0.61 | — |
| Medication | 2,649 (191) | 2,503 (188) | 146 (−380 to 672) | 0.59 | — |
| Total | 6,316 (591) | 6,066 (581) | 250 (−1,375 to 1,874) | 0.76 | — |
| Hispanic/Latino | |||||
| Hospitalization | 2,276 (269) | 1,468 (267) | 808 (65 to 1,551) | 0.03 | — |
| Outpatient | 1,742 (113) | 1,545 (112) | 197 (−114 to 508) | 0.21 | — |
| Medication | 3,031 (119) | 2,654 (118) | 377 (47 to 707) | 0.02 | — |
| Total | 7,048 (369) | 5,666 (366) | 1,382 (363 to 2,401) | 0.008 | — |
| Non-Hispanic white | |||||
| Hospitalization | 3,072 (120) | 2,752 (120) | 320 (−13 to 652) | 0.06 | — |
| Outpatient | 2,583 (50) | 2,511 (50) | 72 (−67 to 211) | 0.31 | — |
| Medication | 4,104 (53) | 3,845 (53) | 260 (112 to 407) | 0.001 | — |
| Total | 9,760 (164) | 9,108 (164) | 652 (196 to 1,107) | 0.005 | — |
| Other/multiple races | |||||
| Hospitalization | 3,472 (569) | 2,225 (539) | 1,248 (−288 to 2,784) | 0.11 | — |
| Outpatient | 2,549 (238) | 2,749 (225) | −200 (−843 to 443) | 0.54 | — |
| Medication | 3,805 (252) | 3,551 (239) | 255 (−427 to 936) | 0.46 | — |
| Total | 9,827 (780) | 8,525 (738) | 1,303 (−803 to 3,408) | 0.22 | — |
Data are mean (SE) unless otherwise indicated. Included are results from ANCOVAs to assess the consistency of differences between intervention groups across subgroups. Negative differences occurred when costs among ILI participants exceeded those for DSE participants; positive differences occurred when costs among ILI participants were less than those for DSE participants. The DSE vs. ILI P values are for the mean difference between intervention groups within each strata. Interaction P values indicate whether the DSE vs. ILI differences were similar among subgroups.
†Weighted ANCOVA.