Table 2.
Multivariable Analysis of Risk Factors for Healthcare Utilization
| Characteristic | Primary HIV CareVisits IRR (95% CI) |
Mental Health Visits IRR (95% CI) |
InpatientVisits IRR (95% CI) |
|---|---|---|---|
| Hepatitis Serostatus | |||
| HIV mono-infection | 1.0 (REF) | 1.0 (REF) | 1.0 (REF) |
| HIV/HBV co-infection | 1.02 (0.97–1.07) | 0.86 (0.69–1.06) | 1.23 (1.05–1.44) |
| HIV/HCV co-infection | 1.02 (0.99–1.05) | 1.27 (1.08–1.50) | 1.22 (1.10–1.36) |
| HIV/HBV/HCV tri-infection | 0.93 (0.86–1.00) | 0.82 (0.57–1.18) | 1.31 (1.02–1.68) |
| Unknown serostatus | 1.01 (0.99–1.03) | 1.24 (1.03–1.48) | 0.93 (0.85–1.03) |
| Age (years)* | |||
| 18 – 34 | 1.0 (REF) | 1.0 (REF) | 1.0 (REF) |
| 35 – 49 | 0.94 (0.92–0.96) | 1.26 (1.05–1.50) | 0.94 (0.86–1.02) |
| 50 – 64 | 1.03 (1.00–1.06) | 1.34 (1.10–1.64) | 1.08 (0.97–1.20) |
| ≥ 65 | 1.08 (1.02–1.15) | 1.08 (0.76–1.53) | 1.49 (1.21–1.83) |
| Race/Ethnicity | |||
| White | 1.0 (REF) | 1.0 (REF) | 1.0 (REF) |
| Black | 1.04 (1.01–1.06) | 0.60 (0.53–0.69) | 1.07 (0.98–1.17) |
| Hispanic | 1.04 (1.01–1.07) | 0.50 (0.41–0.60) | 1.03 (0.93–1.15) |
| Other/Unknown | 0.98 (0.93–1.04) | 0.47 (0.33–0.68) | 0.77 (0.58–1.02) |
| Gender | |||
| Male | 1.0 (REF) | 1.0 (REF) | 1.0 (REF) |
| Female | 1.09 (1.07–1.12) | 1.54 (1.29–1.84) | 1.16 (1.06–1.26) |
| HIV risk factor | |||
| Heterosexual | 1.0 (REF) | 1.0 (REF) | 1.0 (REF) |
| MSM† | 1.02 (1.00–1.05) | 1.65 (1.41–1.93) | 0.90 (0.82–1.00) |
| IDU‡ | 1.04 (1.01–1.08) | 1.49 (1.24–1.79) | 1.28 (1.14–1.43) |
| Other/Unknown | 0.98 (0.93–1.04) | 1.34 (0.58–3.10) | 1.54 (1.27–1.87) |
| CD4 count (cells/mm3)# | |||
| >500 | 1.0 (REF) | 1.0 (REF) | 1.0 (REF) |
| 201–500 | 1.07 (1.05–1.08) | 0.96 (0.88–1.04) | 1.53 (1.41–1.65) |
| 51–200 | 1.20 (1.18–1.23) | 0.95 (0.83–1.08) | 3.15 (2.86–3.47) |
| ≤ 50 | 1.49 (1.44–1.54) | 0.80 (0.67–0.95) | 7.49 (6.79–8.26) |
| HIV-1 RNA (copies/mL)# | |||
| <400 | 1.0 (REF) | 1.0 (REF) | 1.0 (REF) |
| ≥400 | 1.21 (1.19–1.22) | 1.09 (1.00–1.18) | 1.71 (1.60–1.82) |
| ART§ | |||
| No | 1.0 (REF) | 1.0 (REF) | 1.0 (REF) |
| Yes | 1.20 (1.18–1.23) | 1.10 (0.97–1.25) | 0.94 (0.86–1.03) |
| Insurance# | |||
| Private | 1.0 (REF) | 1.0 (REF) | 1.0 (REF) |
| Medicaid | 1.17 (1.13–1.20) | 1.66 (1.42–1.94) | 1.82 (1.60–2.07) |
| Medicare/Dual eligible | 1.16 (1.13–1.19) | 1.46 (1.24–1.72) | 1.75 (1.53–2.01) |
| Ryan White/Uninsured | 1.22 (1.19–1.25) | 1.63 (1.36–1.95) | 1.21 (1.07–1.38) |
| Unknown/Missing | 0.69 (0.66–0.72) | 0.70 (0.55–0.88) | 0.65 (0.50–0.85) |
| Year | |||
| 2006 | 1.0 (REF) | 1.0 (REF) | 1.0 (REF) |
| 2007 | 0.93 (0.91–0.95) | 1.07 (0.98–1.16) | 1.14 (1.05–1.24) |
| 2008 | 0.93 (0.91–0.94) | 1.12 (1.01–1.24) | 1.05 (0.97–1.14) |
| 2009 | 0.93 (0.92–0.95) | 0.90 (0.82–0.99) | 1.20 (1.11–1.31) |
| 2010 | 0.93 (0.91–0.95) | 0.71 (0.64–0.79) | 1.17 (1.07–1.27) |
| 2011 | 0.85 (0.83–0.87) | 0.66 (0.60–0.73) | 1.06 (0.96–1.16) |
*
Age was assessed annually on July 1.
†
Patients who reported sex with both men and women were categorized as MSM.
‡
Patients who reported IDU in addition to any other risk factor were categorized as IDU.
#
CD4, HIV-1 RNA, and insurance data are the first available for each year.
§
ART refers to concurrent use of ≥3 antiretroviral medications from ≥2 classes at any time during the calendar year.
The unit of analysis for all models was person-year. Incidence rate ratios (IRRs) are interpreted as the relative number of visits compared to the reference group after adjusting for other listed characteristics and clinical care site. Statistically significant results (p≤0.05) are shown in bold.