Retrospective analysis of adherence to HIV treatment and healthcare utilization in a commercially insured population

Figures & data

Table 1. Baseline patient demographic characteristics, overall and stratified by STR vs MTR.^a.

Demographic characteristics^b	Overall N = 15,153	STR N = 8,715	MTR N = 6,438
Age (years) at index, mean ± SD	43.9 ± 10.3	42.2 ± 10.4	46.2 ± 9.7
Age (years) by categories, n (%)
18–29	1,758 (11.6)	1,320 (15.1)	438 (6.8)
30–39	3,358 (22.2)	2,215 (25.4)	1,143 (17.8)
40–49	5,563 (36.7)	3,068 (35.2)	2,495 (38.8)
50–59	3,731 (24.6)	1,792 (20.6)	1,939 (30.1)
60–69	646 (4.3)	285 (3.3)	361 (5.6)
>69	97 (0.6)	35 (0.4)	62 (1.0)
Male, n (%)	13,285 (87.7)	7,764 (89.1)	5,521 (85.8)
Geographic region, n (%)
South	7,987 (52.7)	4,688 (53.8)	3,299 (51.2)
West	2,880 (19.0)	1,535 (17.6)	1,345 (20.9)
Midwest	2,541 (16.8)	1,478 (17.0)	1,063 (16.5)
Northeast	1,708 (11.3)	984 (11.3)	724 (11.2)
Other^c	37 (0.2)	30 (0.3)	7 (0.1)
Year of index, n (%)
2011	6,146 (40.6)	2,942 (33.8)	3,204 (49.8)
2012	2,154 (14.2)	1,174 (13.5)	980 (15.2)
2013	1,539 (10.2)	953 (10.9)	586 (9.1)
2014	1,629 (10.8)	975 (11.2)	654 (10.2)
2015	1,929 (12.7)	1,361 (15.6)	568 (8.8)
2016	1,756 (11.6)	1,310 (15.0)	446 (6.9)
Years of follow-up mean ± SD	3.02 ± 1.72	2.88 ± 1.66	3.21 ± 1.78
4 or more years, n (%)	3,818 (25.2)	1,961 (22.5)	1,857 (28.8)
Treatment history, n (%)
Naïve	2,772 (18.3)	2,080 (23.9)	692 (10.7)
Experienced	12,381 (81.7)	6,635 (76.1)	5,746 (89.3)

^aFor MTRs, a complete ART regimen is comprised of at least three agents, including a core and backbone agent, across at least two classes.

^bPatient demographics were identified at the date of the index.

^cOther regions include Puerto Rico and unknown regions.

ART: antiretroviral therapy; MTR: multi-tablet regimen; SD: standard deviation; STR: single-tablet regimen.

Table 2. Adherence during the first year of follow-up and across 4-years of follow-up.

PDC during first year of follow-up	Overall N = 15,153	STR N = 8,715	MTR N = 6,438	Adjusted p-value^a
All PLHIV, n (%)	87 (17)	88 (15)	85 (18)	<.001
PDC ≥ 90%, n (%)	9,517 (63)	5,794 (67)	3,723 (58)	<.001
PDC among PLHIV with ≥4 years of follow-up (PDC ≥ 90%, n (%))	Overall N = 3,818	STR N = 1,961	MTR N = 1,857	Adjusted p-value^a
1^st year	2,569 (67)	1,397 (71)	1,172 (63)	<.001
2^nd year	2,122 (57)	1,206 (63)	916 (51)	<.001
3^rd year	2,008 (57)	1,166 (61)	842 (51)	<.001
4^th year	1,804 (53)	1,090 (58)	714 (46)	<.001
PDC category, n (%)	Year 1 N = 15,153	Year 2 subgroup^b N = 9,494	Year 3 subgroup^c N = 5,821	Year 4 subgroup^d N = 3,818
Very high, ≥95%	6,245 (41)	2,879 (30)	1,452 (25)	846 (22)
High, 90% to < 95%	3,272 (22)	2,416 (25)	1,544 (27)	1,056 (28)
Moderate, 80% to < 90%	2,556 (17)	1,703 (18)	1,073 (18)	688 (18)
Low, <80%	3,080 (20)	2,496 (26)	1,752 (30)	1,228 (32)

^aSTR vs MTR multivariate-adjusted comparisons were conducted using logistic, negative binomial, or linear regressions for binary, count or continuous measures of PDC, respectively, accounting for baseline characteristics with statistically significant differences (all demographic variables, select comorbidities and comedications, and select baseline healthcare resource use).

^bPLHIV with ≥2 years of follow-up.

^cPLHIV with ≥3 years of follow-up.

^dPLHIV with ≥4 years of follow-up.

HIV: human immunodeficiency virus; MTR: multi-tablet regimen; PDC: proportion of days covered; PLHIV: people living with HIV; SD: standard deviation; STR: single-tablet regimen.

Figure 1. Proportion of PLHIV with ≥90% adherence over time with ≥4 years of follow-up, stratified by STR vs MTR. Wilcoxon rank-sum tests and Chi-square tests were used for comparison of continuous and categorical variables, respectively. Comparisons between STR and MTR by year that were significant at the p < .001 level are marked with an asterisk (*). HIV: human immunodeficiency virus; MTR: multi-tablet regimen; PLHIV: people living with HIV; STR: single-tablet regimen.

Table 3. All-cause and HIV-related HRU in the overall sample during the observation period and stratified by ART regimen.

All-cause HRU	Overall N = 15,153	STR N = 8,715	MTR N = 6,438	Adjusted p-value^e
IP stays^a
Number of stays, mean ± SD^b	0.09 ± 0.36	0.08 ± 0.32	0.11 ± 0.40	<.001
≥1 IP stay, n (%)	2,175 (14)	1,014 (12)	1,161 (18)	<.001
Length of stay (days), mean ± SD^c	6.43 ± 10.01	6.11 ± 7.59	6.68 ± 11.57	.639
OP visits
Number of total visits, mean ± SD	11.95 ± 11.87	10.87 ± 10.54	13.41 ± 13.32	<.001
≥1 OP visit, n (%)	15,131 (99.9)	8,702 (99.9)	6,429 (99.9)	.698
≥1 ER visit, n (%)	5,792 (38)	3,118 (36)	2,674 (42)	<.001
HIV-related HRU^d
IP stays
Number of stays, mean ± SD	0.06 ± 0.27	0.05 ± 0.23	0.07 ± 0.31	<.001
≥1 IP stay, n (%)	1,563 (10)	704 (8)	859 (13)	<.001
Length of stay (days), mean ± SD	5.93 ± 10.16	5.64 ± 7.66	6.16 ± 11.73	.654
OP visits
Number of total visits, mean ± SD	5.13 ± 3.32	4.81 ± 2.96	5.57 ± 3.71	<.001
≥1 OP visit, n (%)	15,079 (99.5)	8,665 (99.4)	6,414 (99.6)	.626
≥1 ER visit, n (%)	3,212 (21)	1,663 (19)	1,549 (24)	<.001

^aIP includes both acute care and skilled nursing facility claims.

^bNumber of visits were calculated on a per-person-per-year basis.

^cLength of stay was calculated on a per-stay basis across all stays during the study period.

^dHIV-related HRU encounters were determined by identifying claims with an associated HIV diagnosis code (ICD-9-CM: 042, V08; ICD-10-CM: B20 and Z21).

^eMultivariate adjusted comparisons were conducted using logistic, negative binomial, or linear regressions for binary, count or continuous measures of PDC, respectively, accounting for baseline characteristics with statistically significant differences (all demographic variables, select comorbidities and comedications, and select baseline healthcare resource use).

ART: antiretroviral therapy; ER: emergency room; HIV: human immunodeficiency virus; HRU: healthcare resource utilization; ICD-9/10-CM: International Classification of Diseases, Ninth/Tenth Revision, Clinical Modification; IP: inpatient; MTR: multi-tablet regimen; OP: outpatient; SD: standard deviation; STR: single-tablet regimen.

Figure 2. The proportion of PLHIV with ≥1 HIV-related ER or IP stays with ≥4-years of follow-up, by adherence category. Adherence among PLHIV was categorized as low for PDC <80%, moderate for 80–90%, high for 90–95%, or very high for PDC ≥95%. The difference between the low and very high adherence at the 4-year follow-up was: IP stay, 15.1% vs 7.2%, p < .0001 and ER visit, 26.9% vs 17.1%, p < .0001. ER: emergency room; HIV: human immunodeficiency virus; IP: inpatient; PDC: proportion of days covered; PLHIV: people living with HIV.