Demographic Characteristics of HIV-infected Patients
A total of 9791 HIV-infected patients were found to meet the inclusion criteria. Characteristics of these patients are shown in Table 1. Approximately 69% (n = 6772) of individuals were aged between 18–49 years; 80.4% were males, and 44.4% were married. The main HIV infection route was heterosexual contact (51.9%), and the most common first-line ART regimen was TDF + 3TC + EFV (87.1%, n = 8525). About half of the individuals started ART within 30 days of diagnosis (48.7%, n = 4772) and had CD4 counts ≥ 200 cells/mm3 before ART(56.7%, n = 5549). In this study, 4907 (50.1%) patients had a VL test when ARTs were initiated. The percentage of patients with baseline VL results < 10,000 copies/mL, 10,000–99,999 copies/mL, and ≥ 100,000 copies/mL was 18.4%, 43.3%, and 38.3%, respectively.
Table 1
Characteristics of HIV patients initiating ART between 2012 and 2018 in Chongqing, China
Variables
|
Entire study cohort
N (%)
|
Baseline viral load testing
|
P value
|
Yes
N (%)
|
No
N (%)
|
Total
|
9791(100)
|
4907(100)
|
4884(100)
|
|
Age(years)
|
|
|
|
0.087
|
18–49
|
6772(69.2)
|
3433(70.0)
|
3339(68.4)
|
|
≥50
|
3019(30.8)
|
1474(30.0)
|
1545(31.6)
|
|
Sex
|
|
|
|
0.247
|
Male
|
7870(80.4)
|
3967(80.8)
|
3903(79.9)
|
|
Female
|
1921(19.6)
|
940(19.2)
|
981(20.1)
|
|
Marital status
|
|
|
|
< 0.001
|
Single
|
3905(39.9)
|
1901(38.7)
|
2004(41.0)
|
|
Married
|
4343 (44.3)
|
2277(46.4)
|
2066(42.3)
|
|
Divorced and others
|
1543(15.8)
|
729(14.9)
|
814(16.7)
|
|
Transmission route
|
|
|
|
< 0.001
|
Heterosexual contact
|
5085(51.9)
|
2505(51.0)
|
2580(52.8)
|
|
Homosexual contact
|
3856(39.4)
|
1919(39.1)
|
1937(39.7)
|
|
Injection drug use
|
81(0.8)
|
28(0.6)
|
53(1.1)
|
|
Unknown
|
769(7.9)
|
455(9.3)
|
314(6.4)
|
|
Baseline CD4 counts (cells/mm3)
|
|
|
|
< 0.001
|
< 200
|
4006(40.9)
|
2345(47.8)
|
1661(34.0)
|
|
≥ 200
|
5549(56.7)
|
2508(51.1)
|
3041(62.3)
|
|
Unknown
|
236(2.4)
|
54(1.1)
|
182(3.7)
|
|
Initial ART regimen
|
|
|
|
< 0.001
|
TDF + 3TC + EFV
|
8525(87.1)
|
4569(93.1)
|
3956(81.0)
|
|
Others
|
1266(12.9)
|
338(6.9)
|
928(19.0)
|
|
Year of ART initiation
|
|
|
|
< 0.001
|
2012–2015
|
4524(46.2)
|
2019(41.1)
|
2505(51.3)
|
|
2016–2018
|
5267(53.8)
|
2888(58.9)
|
2379(48.7)
|
|
Duration from HIV diagnosis to ART (days)
|
|
|
|
< 0.001
|
≤ 30
|
4772(48.7)
|
2779(56.6)
|
1993(40.8)
|
|
31–365
|
3655(37.3)
|
1589(32.4)
|
2066(42.3)
|
|
> 365
|
1364(14.0)
|
539(11.0)
|
825(16.9)
|
|
Baseline viral load (copies/ml)
|
|
|
|
-
|
< 10,000
|
903(9.2)
|
903(18.4)
|
-
|
|
10,000–99,999
|
2126(21.7)
|
2126(43.3)
|
-
|
|
≥ 100,000
|
1878(19.2)
|
1878(38.3)
|
-
|
|
Untested
|
4884(49.9)
|
-
|
4884(100)
|
|
Note. TDF, Tenofovir; 3TC, Lamivudine; EFV, Efavirenz. |
Effects of baseline VL on Death
The early mortality rate (deaths within the first 12 months) and the overall mortality rate (deaths during entire observation period) were 4.0 per 100 PY(370 deaths) and 2.1 per 100 PY (707 deaths) (Table 2). ART initiation at higher VL and absence of baseline VL testing were significantly associated with early deaths (10,000–99,999 copies/mL: AHR = 2.4; ≥100,000 copies/mL: AHR = 3.4; and untested: AHR = 2.6), and patients with VL ≥ 100,000 copies/mL exhibited a higher risk of overall mortality (AHR = 1.7). However, there was no association between baseline VL and mortality from 12 months to termination.
Table 2
Effects of baseline viral load on death among HIV patients initiating ART in Chongqing, China, 2012–2018
Baseline viral load (copies/ml)
|
Number
|
Deaths
|
Observed time (PY)
|
Mortality rate per 100 PY
|
HR
(95% CI)
|
P value
|
AHR
(95% CI)
|
P value
|
Study cohort observed from initiation to 12 months
|
Overall
|
9791
|
370
|
9337.4
|
4.0(3.6,4.4)
|
|
|
|
|
< 10,000
|
903
|
8
|
877.6
|
0.9(0.3,1.5)
|
1.0
|
|
1.0
|
|
10,000–99,999
|
2126
|
60
|
2045.4
|
2.9(2.2,3.7)
|
3.2(1.5,6.6)
|
0.002
|
2.4(1.1,5.0)
|
0.021
|
≥ 100,000
|
1878
|
131
|
1754.6
|
7.5(6.2,8.7)
|
8.1(4.0,16.6)
|
< 0.001
|
3.4(1.7,7.0)
|
0.001
|
Untested
|
4884
|
171
|
4659.8
|
3.7(3.1,4.2)
|
4.0(2.0,8.1)
|
< 0.001
|
2.6(1.3,5.3)
|
0.009
|
Study cohort observed from 12 months to termination
|
Overall
|
9058
|
337
|
24379.0
|
1.4(1.2,1.5)
|
|
|
|
|
< 10,000
|
860
|
24
|
2309.3
|
1.0(0.6,1.5)
|
1.0
|
|
1.0
|
|
10,000–99,999
|
1993
|
49
|
4781.1
|
1.0(0.7,1.3)
|
1.0 (0.6,1.6)
|
0.935
|
0.9(0.6,1.5)
|
0.781
|
≥ 100,000
|
1682
|
76
|
4095.3
|
1.9(1.4,2.3)
|
1.8(1.1,2.8)
|
0.016
|
1.1(0.7,1.7)
|
0.835
|
Untested
|
4523
|
188
|
13193.3
|
1.4(1.2,1.6)
|
1.4(0.9,2.1)
|
0.148
|
1.0(0.6,1.5)
|
0.983
|
Entire study cohort
|
Overall
|
9791
|
707
|
33716.4
|
2.1(1.9,2.2)
|
|
|
|
|
< 10,000
|
903
|
32
|
3186.9
|
1.0(0.7,1.4)
|
1.0
|
|
1.0
|
|
10,000–99,999
|
2126
|
109
|
6826.5
|
1.6(1.3,1.9)
|
1.5(1.0,2.3)
|
0.036
|
1.3(0.9,1.9)
|
0.196
|
≥ 100,000
|
1878
|
207
|
5849.9
|
3.5(3.1,4.0)
|
3.4(2.3,4.9)
|
< 0.001
|
1.7(1.2,2.5)
|
0.006
|
Untested
|
4884
|
359
|
17853.1
|
2.0(1.8,2.2)
|
2.0(1.4,2.9)
|
< 0.001
|
1.4(1.0,2.0)
|
0.076
|
*PY = person years; HR = hazard ratio; AHR = adjusted hazard ratio; covariates of the adjusted model included: age, sex, marital status, transmission route, baseline CD4 counts, initial ART regimen, year of ART initiation, duration from HIV diagnosis to ART. |
Effects of baseline VL on Virologic Failure
Of the 5043 patients who had VL tested at 12 months after treatment initiation, 230 patients (4.6%) exhibited virologic failure (Table 3). The virologic failure rate of patients with pre-ART VL < 10,000 copies/mL, 10,000–99,999 copies/mL, ≥ 100,000 copies/mL and untested were 1.3%, 2.8%, 7.0%, and 5.3%, respectively. The adjusted model showed that both VL ≥ 100,000 copies/mL and being untested for VL increased the risk of virologic failure, compared with VL < 10,000 copies/mL (≥ 100,000 copies/mL: AOR = 3.5; untested: AOR = 3.2).
Table 3
Effects of baseline viral load on virologic failure at 12 months among HIV patients initiating ART in Chongqing, China, 2012–2018
Variables
|
Number
|
Virologic failure
|
Virologic failure rate (95% CI)
|
OR
(95% CI)
|
P value
|
AOR
(95% CI)
|
P value
|
Overall
|
5043
|
230
|
4.6(4.0,5.1)
|
|
|
|
|
Baseline viral load (copies/ml)
|
< 10,000
|
522
|
7
|
1.3(0.4,2.3)
|
1.0
|
|
1.0
|
|
10,000–99,999
|
1272
|
35
|
2.8(1.9,3.7)
|
2.1(0.9,4.7)
|
0.079
|
1.7(0.8,4.0)
|
0.185
|
≥ 100,000
|
961
|
67
|
7.0(5.4,8.6)
|
5.5(2.5,12.1)
|
< 0.001
|
3.5(1.6,7.8)
|
0.002
|
Untested
|
2288
|
121
|
5.3(4.4,6.2)
|
4.1(1.9,8.9)
|
< 0.001
|
3.2(1.5,6.9)
|
0.003
|
*OR = odds ratio; AOR = adjusted odds ratio; virologic failure: VL ≥ 200 copies/ml; covariates of the adjusted model included: age, sex, marital status, transmission route, baseline CD4 counts, initial ART regimen, year of ART initiation, duration from HIV diagnosis to ART. |
Effects of baseline VL on death stratified by baseline CD4 counts
Given the interaction between VL and CD4 counts, a further analysis by stratification is presented in Table 4. In the different groups of baseline CD4, ART initiation at higher VL was significantly associated with early death (<200 cells/mm3: AHR = 3.3; ≥200 cells/mm3: AHR = 5.0), but there was no significant difference in the entire cohort.
Table 4
Effects of baseline viral load on death stratified by baseline CD4 counts among HIV patients initiating ART in Chongqing, China, 2012–2018
Baseline viral load (copies/ml)
|
CD4 < 200 cells/mm3
|
CD4 ≥ 200 cells/mm3
|
Deaths
|
Mortality rate per 100 PY
|
AHR
(95% CI)
|
P value
|
Deaths
|
Mortality rate per 100 PY
|
AHR
(95% CI)
|
P value
|
Study cohort observed from initiation to 12 months
|
Overall
|
285
|
7.6
|
|
|
73
|
1.4
|
|
|
< 10,000
|
5
|
2.4
|
1.0
|
|
2
|
0.3
|
1.0
|
|
10,000–99,999
|
43
|
5.9
|
2.3(0.9,5.8)
|
0.081
|
17
|
1.3
|
3.5(0.8,15.5)
|
0.092
|
≥ 100,000
|
119
|
9.6
|
3.3(1.4,8.2)
|
0.009
|
12
|
2.4
|
5.0(1.1,22.7)
|
0.036
|
Untested
|
118
|
7.6
|
2.5(1.0,6.2)
|
0.043
|
42
|
1.4
|
3.2(0.8,13.5)
|
0.106
|
Entire study cohort
|
Overall
|
476
|
3.7
|
|
|
205
|
1.0
|
|
|
< 10,000
|
16
|
2.1
|
1.0
|
|
15
|
0.6
|
1.0
|
|
10,000–99,999
|
70
|
3.1
|
1.3(0.7,2.2)
|
0.366
|
37
|
0.8
|
1.3(0.7,2.3)
|
0.457
|
≥ 100,000
|
178
|
4.4
|
1.6(1.0,2.7)
|
0.068
|
28
|
1.6
|
1.9(1.0,3.5)
|
0.050
|
Untested
|
212
|
3.6
|
1.3(0.8,2.2)
|
0.263
|
125
|
1.1
|
1.4(0.8,2.3)
|
0.269
|
*PY = person years; AHR = adjusted hazard ratio; covariates of the adjusted model included: age, sex, marital status, transmission route, initial ART regimen, year of ART initiation, duration from HIV diagnosis to ART. |