Table 1.

Hospitalisation rates and cost by current CD4 cell count and site (urban versus rural) in patients before and after ART initiation in a prospective cohort study in two sites in South Africa.

CD4 cell count stratum	Total patient years (%)	Number of hospitalisations	Hospitalisation rate per 100 patient years (95% CI)	Crude IRR1 of hospitalisation by CD4 count (95% CI2)	Mean length of stay [days] (95% CI)	Mean cost per stay [2009 USD] (95% CI)	Mean inpatient cost per patient year in cohort [2009 USD] (95% CI)
Both sites
Pre-ART3
≤100 cells/mm3	602.8 (8.6)	60	10.0 (7.6–12.8)	1.0	10.4 (7.4–13.4)	1,759 (1,254–2,263)	176 (95–290)
101–200 cells/mm3	1,233.9 (17.6)	78	6.3 (5.0–7.9)	0.6 (0.4–0.9)	8.6 (5.9–11.2)	1,453 (988–1,919)	92 (49–152)
201–350 cells/mm3	2,275.6 (32.5)	109	4.8 (3.9–5.8)	0.5 (0.3–0.7)	8.7 (6.7–10.6)	1,452 (1,126–1,778)	70 (44–103)
>350 cells/mm3	2,889.5 (41.3)	97	3.4 (2.7–4.1)	0.3 (0.2–0.5)	7.8 (5.6–10.0)	1,290 (934–1,645)	44 (25–67)
All pre-ART patients	7,001.7	344	4.9 (4.4–5.4)	-	8.7 (7.5–9.9)	1,460 (1,267–1,657)	72 (56–89)
On ART
≤100 cells/mm3	134.8 (5.3)	27	20.0 (13.2–29.1)	1.0	12.1 (6.6–17.5)	2,043 (1,128–2,957)	409 (149–860)
101–200 cells/mm3	456.9 (17.4)	44	9.6 (7.0–12.9)	0.5 (0.3–0.8)	13.4 (8.0–18.7)	2,241 (1,345–3,137)	216 (94–405)
201–350 cells/mm3	1024.8 (35.2)	75	7.3 (5.8–9.2)	0.4 (0.2–0.6)	9.3 (7.4–11.2)	1,559 (1,241–1,876)	114 (72–173)
>350 cells/mm3	1123.7 (42.1)	44	3.9 (2.8–5.3)	0.2 (0.1–0.3)	6.9 (4.8–9.0)	1,158 (805–1,511)	45 (23–80)
All ART patients	2740.2	190	6.9 (6.0–8.0)	-	10.1 (8.4–11.8)	1,693 (1,409–1,976)	117 (85–158)
Urban clinic
Pre-ART
≤100 cells/mm3	357.2 (6.9)	40	11.2 (8.0–15.2)	1.0	8.9 (4.9–13.0)	1,465 (801–2,129)	164 (64–324)
101–200 cells/mm3	827.1 (16.0)	57	6.9 (5.2–8.9)	0.6 (0.4–0.9)	6.4 (5.2–7.5)	1,049 (861–1,236)	72 (45–110)
201–350 cells/mm3	1,695.6 (32.6)	88	5.2 (4.2–6.4)	0.5 (0.3–0.7)	7.6 (5.8–9.5)	1,256 (950–1,562)	65 (40–100)
>350 cells/mm3	2,314.6 (44.6)	90	3.9 (3.1–7.8)	0.3 (0.3–0.5)	7.6 (5.3–9.9)	1,253 (876–1,631)	49 (27–127)
All pre-ART patients	5,194.5	275	5.3 (4.7–5.9)	-	7.6 (6.4–8.7)	1,242 (1,057–1,428)	66 (50–84)
On ART
≤100 cells/mm3	96.1 (4.4)	16	16.6 (9.5–27.0)	1.0	12.0 (3.6–20.4)	1,970 (595–3,345)	328 (57–903)
101–200 cells/mm3	355.0 (16.1)	34	9.6 (6.6–13.4)	0.6 (0.3–1.0)	12.3 (6.1–18.4)	2,014 (1,001–3,027)	193 (66–406)
201–350 cells/mm3	833.7 (37.8)	53	6.4 (4.8–8.3)	0.4 (0.2–0.7)	9.3 (6.8–11.8)	1,524 (1,110–1,938)	97 (53–161)
>350 cells/mm3	918.5 (41.7)	34	3.7 (2.6–5.2)	0.2 (0.1–0.4)	6.4 (3.9–8.9)	1,053 (648–1,457)	39 (17–76)
All ART patients	2203.3	137	6.2 (5.2–7.4)	-	9.6 (7.5–11.7)	1,581 (1,239–1,923)	98 (64–142)
Rural clinic
Pre-ART
≤100 cells/mm3	245.6 (13.6)	20	8.1 (5.0–12.6)	1.0	13.3 (9.1–17.5)	2.,345 (1,608–3,081)	191 (80–388)
101–200 cells/mm3	406.7 (22.5)	21	5.2 (3.2–7.9)	0.6 (0.3–1.4)	14.5 (5.1–23.9)	2,552 (894–4,210)	132 (29–333)
201–350 cells/mm3	580.0 (32.1)	21	3.6 (2.2–5.5)	0.4 (0.2–0.9)	12.9 (6.6–19.2)	2,275 (1,171–3,379)	82 (26–186)
>350 cells/mm3	574.9 (31.8)	7	1.2 (0.5–2.5)	0.1 (0.06–0.4)	10.0 (4.4–15.6)	1,763 (776–2,750)	21 (4–69)
All pre-ART patients	1,807.1	69	3.8 (3.0–4.8)	-	13.2 (9.7–16.7)	2,328 (1,716–2,939)	89 (51–141)
On ART
≤100 cells/mm3	38.7 (7.2)	11	28.4 (14.2–50.9)	1.0	12.2 (4.7–19.7)	2,148 (826–3,469)	611 (117–1766)
101–200 cells/mm3	101.9 (19.0)	10	9.8 (4.7–18.0)	0.3 (0.1–0.9)	17.1 (4.4–19.8)	3,015 (783–5,246)	296 (37–944)
201–350 cells/mm3	191.1 (35.6)	22	11.5 (7.2–17.4)	0.4 (0.2–0.9)	9.3 (6.7–12.0)	1,643 (1,174–2,111)	189 (85–367)
>350 cells/mm3	205.2 (38.2)	10	4.9 (2.3–9.0)	0.2 (0.06–0.4)	8.6 (3.9–13.2)	1,516 (692–2,340)	74 (16–211)
All ART patients	536.9	53	9.9 (7.4–12.9)	-	11.2 (8.4–14.1)	1,982 (1,473–2,492)	196 (109–321)

¹incident rate ratios

²confidence interval

³antiretroviral therapy