Research Article

Impact on Medical Cost, Cumulative Survival, and Cost-Effectiveness of Adding Rituximab to First-Line Chemotherapy for Follicular Lymphoma in Elderly Patients: An Observational Cohort Study Based on SEER-Medicare

Table 2

Multivariate cost analysis—all patients.

Type of cost
Total Immunochemotherapy Other cancer Noncancer
Coef.95% CICoef.95% CICoef.95% CICoef.95% CI
LowerUpperLowerUpperLowerUpperLowerUpper

First-lines therapy
 Chemotherapy aloneReference category
 Rituximab plus chemotherapy$18,695 $9,302$28,643$13,336 $9,364$17,552$4,816 −$1,899$11,303$351 −$3,481$4,202
Age at diagnosis (years)
 66–70Reference category
 71–75−$1,618 −$12,630$9,175−$1,220 −$5,593$2,925−$2,270 −$10,015$5,198$1,828 −$1,952$5,472
 76–80−$1,400 −$12,542$10,379−$704 −$5,460$4,345−$3,617 −$10,665$3,634$3,083 −$921$7,077
 >80−$9,865 −$22,344$1,980−$8,374 −$13,699−$3,221−$943 −$8,575$6,986−$504−$4,521$3,435
Gender
 MaleReference category
 Female−$7,732 −$16,027$19−$2,628 −$6,155$730−$3,64 5 −$9,104$1,701−$1,48 9 −$4,739$1,455
Race/ethnicity
 WhiteReference category
 Black$7,307 −$26,205$44,598$4,496 −$8,111$20,403$9,852 −$8,428$31,109−$5,999 −$15,809$406
 Hispanic$15,780 −$6,890$41,915−$1,316 −$7,856$5,837$16,990 −$502$36,055−$53 −$6,339$6,827
 Other−$29,492 −$45,805−$13,944−$15,023 −$20,618−$8,565−$6,436 −$17,445$5,516−$7,869 −$14,022−$1,893
Year of diagnosis
 1999–2002Reference category
 2003–2005$4,638 −$4,847$13,587$3,148 −$593$7,091$534 −$5,996$6,482$1,176 −$2,202$4,629
Stage at FL diagnosis
 I & IIReference category
 III & IV$7,953 −$382$16,574$5,955 $2,569$9,367$5,363 −$472$11,028−$3,280 −$6,676$210
Histology (grade)
 1Reference category
 2$3,350 −$8,410$14,992$1,175 −$3,653$6,292−$482 −$9,605$8,380$2,659 −$2,156$7,226
 3−$2,251 −$13,262$8,903−$3,576 −$8,221$909$519 −$7,512$9,077$645 −$3,791$5,058
 4−$6,155 −$17,656$3,862−$4,305 −$8,814$585−$3,237 −$10,800$4,653$1,452 −$2,697$5,447
Extranodal involvement
 NoReference category
 Yes$15,429 $6,543$25,246$614 −$2,870$4,076$12,827 $6,714$19,419$2,282 −$924$5,733
Presence of “B” symptoms
 NoReference category
 Yes$7,901 −$5,056$19,189$4,458 −$338$9,085$6,628 −$1,689$15,435−$2,854 −$6,581$544
Anemia
 NoReference category
 Yes$9,471 −$16,737$37,624$7,299 −$2,203$18,918$6,586 −$10,949$24,028−$4,184 −$11,569$3,381
NCI comorbidity index
 0Reference category
 1$9,074 −$325$18,531−$205 −$4,134$3,766$894 −$4,562$5,990$6,320 $2,334$10,293
 2$21,541 $1,106$43,054−$2,419 −$10,259$6,117$14,441 $2,063$27,760$10,422 $3,978$17,034
 ≥3$51,102 −$4,052$109,569−$13,402 −$20,651−$4,565$28,545 −$221$66,725$35,295 $8,962$63,847
Performance status indicators
 NoneReference category
 ≥1$14,290 $176$28,357$992 −$3,732$6,402$11,482 $3,017$20,859$2,030 −$4,216$8,022
Percent in census tract with some college
 <25%Reference category
 ≥25%−$9,060 −$18,039−$394−$2,377 −$6,119$1,049−$5,302 −$11,598$756−$1,591 −$5,376$1,884
Percent in census tract living in poverty
 <5%Reference category
 5–7%$2,880−$9,216$15,965$2,902−$3,293$9,382$130−$8,385$8,786$35−$3,836$4,240
 8–12%$287−$10,343$10,485$897−$5,483$3,493$841−$8,040$6,266$1,740−$2,250$5,883
 >12%$446−$10,504$10,185$2,183−$6,934$1,760$216−$7,196$7,392$1,387−$2,399$5,359
Type of geographic area
 Large metropolitanReference category
 Metropolitan$8,072−$16,491$209$2,823−$6,417$721$3,636−$10,007$2,971$1,660−$4,971$1,880
 Urban$16,680−$30,663−$1,544$292−$7,743$7,925$11,881−$21,215−$2,092$4,485−$8,889$199
 Less urban/rural$13,484−$23,951−$2,186$3,236−$8,583$1,656$8,269−$15,086−$712$2,286−$7,559$3,189