Impact of completing chronic hepatitis C (CHC) treatment on post-therapy healthcare cost

Figures & data

Figure 1. Patient’s disposition.

Table 1. Demographic and clinical characteristics of the complete and discontinued HCV therapy cohorts.

Baseline characteristics	Complete therapy cohort (n = 1017)	Discontinued therapy cohort (n = 953)	p-value^a
Demographics^b
Age, mean (SD)	49.6 (8.5)	50.4 (8.5)	0.0230
Gender, female, n (%)	387 (38.1%)	366 (38.4%)	0.8724
Type of beneficiary^b, n (%)
Employee	524 (51.5%)	488 (51.2%)	0.8880
Spouse/dependent/retiree	493 (48.5%)	465 (48.8%)	0.8880
Year of index date^b, n (%)
2001	84 (8.3%)	60 (6.3%)	0.0943
2002	130 (12.8%)	141 (14.8%)	0.1949
2003	128 (12.6%)	111 (11.6%)	0.5237
2004	122 (12.0%)	102 (10.7%)	0.3663
2005	131 (12.9%)	89 (9.3%)	0.0126
2006	104 (10.2%)	83 (8.7%)	0.2510
2007	97 (9.5%)	92 (9.7%)	0.9305
2008	85 (8.4%)	86 (9.0%)	0.5997
2009	65 (6.4%)	89 (9.3%)	0.0149
2010	57 (5.6%)	83 (8.7%)	0.0074
2011	14 (1.4%)	17 (1.8%)	0.4680
Region^b, n (%)
Northeast	326 (32.1%)	274 (28.8%)	0.1113
Midwest	121 (11.9%)	138 (14.5%)	0.0900
South	419 (41.2%)	410 (43.0%)	0.4129
West	111 (10.9%)	106 (11.1%)	0.8827
Unknown	40 (3.9%)	25 (2.6%)	0.1038
Insurance^b, n (%)
HMO	110 (10.8%)	129 (13.5%)	0.0646
POS	316 (31.1%)	256 (26.9%)	0.0397
PPO	411 (40.4%)	424 (44.5%)	0.0672
Indemnity	118 (11.6%)	91 (9.5%)	0.1390
Unknown	62 (6.1%)	53 (5.6%)	0.6128
Quan-Charlson comorbidity index^c,d, mean (SD)	1.36 (1.00)	1.47 (1.14)	0.0273
Comorbidities^d, n (%)
Diabetes	108 (10.6%)	134 (14.1%)	0.0201
Psychiatric disease	92 (9.0%)	91 (9.5%)	0.7010
Depression	85 (8.4%)	93 (9.8%)	0.2785
Anemia	59 (5.8%)	85 (8.9%)	0.0079
Substance abuse	49 (4.8%)	52 (5.5%)	0.5209
Coronary arterial disease	34 (3.3%)	43 (4.5%)	0.1810
COPD	29 (2.9%)	47 (4.9%)	0.0166
Autoimmune deficiency	16 (1.6%)	17 (1.8%)	0.7159
Renal failure	16 (1.6%)	21 (2.2%)	0.3031
Bipolar	13 (1.3%)	16 (1.7%)	0.4606
Rheumatoid arthritis	9 (0.9%)	22 (2.3%)	0.0112
Heart failure	7 (0.7%)	11 (1.2%)	0.2774
Psoriasis	7 (0.7%)	11 (1.2%)	0.2774
Non-Hodgkin's lymphoma	7 (0.7%)	1 (0.1%)	0.0419
Epilepsy	5 (0.5%)	4 (0.4%)	0.8130
Kidney transplant	5 (0.5%)	5 (0.5%)	0.9179
Pregnancy	4 (0.4%)	8 (0.8%)	0.2034
Dialysis	4 (0.4%)	7 (0.7%)	0.3098
Lung/heart transplant	2 (0.2%)	1 (0.1%)	0.6018
Schizophrenia	2 (0.2%)	0 (0.0%)	0.1708
Porphyria cutanea tarda	2 (0.2%)	3 (0.3%)	0.6025
Vasculitis	2 (0.2%)	3 (0.3%)	0.6025
Crohn's disease	1 (0.1%)	4 (0.4%)	0.1565
Lichen planus	1 (0.1%)	3 (0.3%)	0.2861
Cardiac arrest	0 (0.0%)	1 (0.1%)	0.3015
Baseline resource utilization^d, mean (SD)
ER visits	0.24 (0.68)	0.25 (0.73)	0.6214
Inpatient visits	0.12 (0.61)	0.16 (0.52)	0.0806
Outpatient visits	10.31 (7.54)	10.71 (9.65)	0.3030
Baseline all-cause healthcare costs^d, US $2012, mean (SD)
Total costs	$10,181 (68,620)	$8575 (23,168)	0.4813
Inpatient costs	$4080 (65,032)	$2323 (18,809)	0.4093
ER costs	$162 (991)	$129 (546)	0.3515
Outpatients costs	$4853 (10,912)	$4770 (8764)	0.8524
Pharmacy costs	$1086 (2050)	$1353 (4368)	0.0855

HCV, hepatitis C virus; SD, standard deviation; HMO, health maintenance organization; POS, point of service; PPO, preferred provider organization; COPD, chronic obstructive pulmonary disease; ER, emergency room.

^aCalculated using the Pearson Chi-square test (categorical variables) and Student’s t-test (continuous variables).

^bEvaluated at the index date.

^cMild and severe liver disease were excluded from the Quan-Charlson comorbidity index.

^dEvaluated during the 6-month baseline period.

Table 2. Treatment patterns of the complete and discontinued HCV therapy cohorts.

Treatment pattern	Complete therapy cohort (n = 1017)	Discontinued therapy cohort (n = 953)	p-value^a
Observation period^b, days, mean (SD)	1731 (999)	1593 (962)	0.0019
Interferon treatment patterns, mean (SD)
Exposure to therapy^c, days	489 (442)	391 (532)	<0.0001
Persistent therapy duration^d, days	353 (84)	108 (71)	<0.0001
Number of dispensing per patient	11.2 (6.1)	6.4 (5.2)	<0.0001
Number of injections per dispensing	4.1 (3.8)	3.5 (3.3)	<0.0001
Days supply per dispensing	42.1 (21.5)	35.9 (17.1)	<0.0001

SD, standard deviation.

^aCalculated using the Pearson Chi-square test (categorical variables) and Student’s t-test (continuous variables).

^bThe observation period spanned from 48 weeks past the index date until the earliest date between the end of insurance coverage or the end of data availability.

^cThe exposure to therapy was defined as the number of days between the first dispensing and the last dispensing plus the day of supply of that last refill.

^dFrom the date of the first dispensing until the treatment interruption or discontinuation, defined as a gap ≥30 days since the last dispensing plus its day of supply.

Figure 2. Comparison of adjusted HRU between the complete (36–48 weeks) vs discontinued HCV therapy cohorts. HRU, healthcare resource utilization; HCV, hepatitis C virus; IP, inpatient; ER, emergency room; OP, outpatient; CHC, chronic hepatitis C. Rate ratios and confidence intervals were calculated using negative binomial regression models, adjusting for baseline characteristics including age, gender, type of beneficiary, geographic region, payer type, year of index date, Quan-Charlson comorbidity index, and total healthcare costs.

Table 3. Comparison of HRU among all beneficiaries in the complete (36–48 weeks) vs incomplete HCV therapy cohorts.

Outcome measures	Number of events		Frequency rate (per patient-year)		Univariate analysis^a
	Complete therapy cohort	Discontinued therapy cohort	Complete therapy cohort	Discontinued therapy cohort	Unadjusted RR (95% CI)	p-value
Number of patients, n	1017	953
Observation period^b, days, mean (SD)	1395 (999)	1257 (962)
All-cause resource Utilization
Hospitalizations	879	1003	0.23	0.31	0.74 (0.68, 0.81)	<0.0001
ER visits	1809	1639	0.47	0.50	0.93 (0.87, 1.00)	0.0393
Outpatient visits	59,994	55,246	15.44	16.84	0.92 (0.91, 0.93)	<0.0001
CHC-related resource Utilization
Hospitalizations	111	174	0.03	0.05	0.54 (0.42, 0.68)	<0.0001
ER visits	13	15	0.00	0.00	0.73 (0.35, 1.54)	0.4102
Outpatient visits	7494	5894	1.93	1.80	1.07 (1.04, 1.11)	<0.0001

HRU, healthcare resource utilization; HCV, hepatitis C virus; RR, rate ratio; CI, confidence interval; SD, standard deviation; ER, emergency room; CHC, chronic hepatitis C.

^aAdjusted rates are reported in Figure 2.

^bThe observation period spanned from 48 weeks past the index date until the earliest date between the end of insurance coverage or the end of data availability.

Table 4. Comparison of PPPY healthcare cost between all beneficiaries in the complete vs discontinued HCV therapy cohorts.

PPPY healthcare costs (US $2012)	Complete therapy cohort	Discontinued therapy cohort	Complete vs discontinued therapy cohort
			Unadjusted cost difference	Adjusted cost difference^a (95% CI)	p-value
Number of patients, n	1017	953
Observation period^b, days, mean (SD)	1395 (999)	1257 (962)
All-cause healthcare costs	$13,294 (28,106)	$17,834 (38,328)	−$4540	−$3687 (−6503, −822)	0.0080
Hospitalizations	$3347 (14,965)	$6386 (28,754)	−$3039	−$2726 (−4734, −821)	0.0020
ER visits	$223 (607)	$286 (913)	−$63	−$56 (−119, 4)	0.0661
Outpatient visits	$5062 (14,602)	$5847 (10,477)	−$785	−$535 (−1537, 603)	0.3884
Pharmacy dispensing	$4663 (8039)	$5315 (10,009)	−$652	−$371 (−1099, 366)	0.3223
CHC-related healthcare costs	$3535 (10,285)	$5286 (21,240)	−$1750	−$1644 (−3138, −148)	0.0220
Hospitalizations	$953 (7852)	$2661 (19,825)	−$1708	−$1734 (−3202, −400)	0.0060
ER visits	$1 (15)	$3 (35)	−$1	−$1 (−4, 1)	0.2142
Outpatient visits	$450 (868)	$544 (1039)	−$94	−$88 (−178, 9)	0.0761
Pharmacy dispensing^c	$2131 (5782)	$2077 (6341)	$54	$179 (−286, 639)	0.4525

PPPY, per-patient per-year; HCV, hepatitis C virus; SD, standard deviation; CHC, chronic hepatitis C; CI, confidence interval; ER, emergency room; RBV, ribavirin.

^aAdjusted cost differences are obtained using ordinary least-squares regressions, adjusting for baseline characteristics including age, gender, type of beneficiary, geographic region, payer type, year of index date, Quan-Charlson comorbidity index, and healthcare costs. Confidence intervals (95% CI) and p-values were calculated using a non-parametric bootstrap with 999 replications.

^bThe observation period spanned from 48 weeks past the index date until the earliest date between the end of insurance coverage or the end of data availability.

^cCHC-related pharmacy dispensing costs were identified with NDC codes for any of these medicated treatments: peginterferon alfa-2a or alfa-2b, interferon alfa-2a or alfa-2b, or interferon alfacon-1, RBV, telaprevir, and boceprevir.