Table 2.

Multivariable regression of adherence percentage on pillbox organizer use and confounders for 237 individuals with 2504 person-years of follow-up.

Term in multivariable linear regression model	Coefficient (95% CI)
Pillbox organizer use	4.47 (1.98–6.97)
Once-daily therapy	0.78 (−3.12 to 4.68)
Adherence, per 10% adherence	6.33 (5.81–6.86)
CD4+ T cell count, per 100 cells/μL	−0.05 (−0.99 to 0.90)
CD4+ T cell count lagged by 2 months, per 100 cells/μL	0.25 (−0.83 to 1.33)
Nadir CD4+ T cell count, per 100 cells/μ	−0.88 (−9.64 to 7.87)
Nadir CD4+ T cell count lagged by 2 months, per 100 cells/mL	1.69 (−6.81 to 10.18)
Viral load, per 100,000 copies/mL	−0.12 (−0.24 to 0.01)
Viral load 2 months prior to study, per 100,000 copies/mL	−0.10 (−0.20 to 0.01)
Calendar date, per 30 days	−0.0− (−0.07 to 0.02)
Duration of current regimen, per 30 days	0.04 (−0.03 to 0.10)
Age, per year	0.14 (0.01–0.28)
No. of days intoxicated in past month, per day	−0.05 (−0.18 to 0.08)
Injection drug use	−3.73 (−6.42 to 31.03)
Slept on street or in shelter	−0.98 (−3.82 to 1.87)
Crack use	−2.46 (−5.14 to 0.22)
Female sex	−2.89 (−5.86 to 0.08)
Man who has sex with men	−0.03 (−2.66 to 2.60)
Blacka	−6.45 (−8.80 to 34.10)
Hispanica	−2.20 (−6.75 to 2.36)
Other ethnicitya	−4.42 (−10.91 to 2.07)
Mono- or dual-nucleoside exposure	−1.45 (−5.45 to 2.54)
Antiretroviral naive, prior to study	0.70 (−2.13 to 3.53)
Unboosted PI-based regimenb	−0.56 (−3.25 to 2.13)
PI- and NNRTI-based regimenb	0.46 (−4.55 to 5.47)
NRTI only regimenb	2.36 (−5.73 to 10.45)
Boosted PI-based regimenb	0.60 (−4.52 to 5.72)
No. of antiretroviral drugs in current regimen, per drug	−0.38 (−2.22 to 1.47)
No. of antiretroviral drugs experienced, per drug	0.24 (−0.53 to 1.01)
No. of treatment regimens experienced, per regimen	0.25 (−2.32 to 2.81)

NOTE. Pill count adherence percentage was calculated as the difference between the current and previous pill counts divided by the prescribed number of doses for the same period. Data was fit using cross-validated deletion/substitution/addition algorithm. Person-years of follow-up includes all person-months with data available for pillbox organizer use, all confounders, and pill count adherence. Data for confounders were lagged by 1 month, unless otherwise noted. NNRTI, nonnucleoside reverse-transcriptase inhibitor; NRTI, nucleoside reverse-transcriptase inhibitor; PI, protease inhibitor.

^aWhite ethnicity as baseline.

^bNNRTI-based regimen as baseline.