234 AIDS/HIV
sometimes required to take as many as 20 pills per day. Al-
though efforts are underway to develop simpli“ed treatment
regimens (Cohen, Hellinger, & Norris, 2000), treatments will
continue to be complex, requiring considerable patient effort
and tracking.
Treatment adherence is a common concern for all areas of
medicine, but it takes on increasing importance in the area of
HIV care because of the severe consequences associated with
even modest deviations from prescribed regimens. Several
studies document a strong association between poor adher-
ence and failure to suppress viral load (Montaner et al., 1998;
Paterson et al., 2000). For example, Paterson et al. (2000) re-
port that failure to maintain viral suppression to undetectable
levels was documented in 22% of patients with adherence of
95% or greater, whereas nearly two-thirds of patients with ad-
herence rates ranging from 80% to 94% experienced virologic
failure. Patients with less than 80% adherence faired even
worse, with only 20% of those patients avoiding drug failure.
Moreover, patients with adherence of 95% or greater had
fewer days in the hospital than those with less than 95% adher-
ence, and experienced no opportunistic infections or deaths.
These dramatic “ndings are particularly noteworthy given that
in other areas of medicine, acceptable adherence levels are
often considered to be in the 80% to 90% range (Haynes,
McKibbon, & Kanani, 1996), and underscore the long-term
self-management challenges faced by HIV-positive patients.
The unforgiving nature of combination therapy treat-
ments suggests that many patients who initiate combi-
nation therapies have a time-limited opportunity to succeed with
treatment. Even brief drug holidays can lead to rapid viral repli-
cation, drug resistance, and (ultimately) failure to respond to
other combination therapies. Further, patients initiating combi-
nation therapy treatments face what may well be a lifetime of
intensive pill taking, given the inevitability of rapid viral •re-
boundŽ among patients who discontinue therapy (Dornadula
et al., 1999). The complexity of the drug regimen is not the only
factor rendering treatment adherence a challenge. Under even
the best of circumstances, combination therapy can cause a host
of unpleasant and sometimes severe side effects including fa-
tigue, nausea, vomiting, and diarrhea, as well as longer term side
effects (i.e., oral numbness, metallic taste, lipodystrophy, and
peripheral neuropathy; Rabkin & Chesney, 1999).
Several studies provide estimates of the prevalence of
therapy adherence problems involving HIV-positive persons.
Among patients recruited from an infectious disease clinic,
17% reported missing one or more doses in the last two days,
and 31% of respondents reported missing one or more doses
of combination therapy in the last “ve days (Catz, Kelly,
Bogart, Benotsch, & McAuliffe, 2000). Similar estimates of
poor adherence were reported in a study involving partici-
pants in a multisite HIV treatment trial (Chesney et al., 2000),
and in a community sample of predominately African
American men and women (Kalichman, Ramachandran, &
Catz, 1999). Adherence based on self-report may underesti-
mate the frequency of missed dosages. A study comparing the
use of self-report, unannounced pill counts, and electronic
pill cap monitoring found that median adherence was 89%,
73%, and 67% by self-report, pill count, and electronic med-
ication monitor, respectively (Bangsberg et al., 2000).Interventions to Promote Adherence. Research inves-
tigating correlates and barriers to HIV treatment adherence
point to the challenges that lie ahead in designing effective
behavioral interventions to improve adherence. Risk factors
that characterize individuals who are at elevated risk for con-
tracting HIV, including poverty, social marginilization, sub-
stance abuse, and mental illness, are also likely to serve as
barriers to HIV treatment adherence. Qualitative research
summarized by Rabkin and Chesney (1999) identi“ed sev-
eral obstacles faced by individuals who lack adequate
economic resources when they try to adhere to their HIV
medications. Patients who are at elevated risk for substance
use disorders (e.g., Malow et al., 1998) and psychiatric ill-
ness (e.g., Stein et al., 2000) are also less likely to adhere to
their medication regimen. These “ndings highlight the
dilemma faced by many physicians when working with indi-
viduals whose life circumstances make adequate treatment
adherence unlikely. Indeed, some physicians argue that be-
cause of the risks of developing multidrug resistance from
poor adherence, some newly diagnosed patients may be
served best by delaying initiation of combination therapies in
favor of “rst treating acute illnesses and resolving other basic
psychosocial issues such as substance abuse, housing, and
health insurance (Bangsberg, Tulsky, Hecht, & Moss, 1997).
Psychosocial factors, including social support, psychol-
ogical distress, and self-ef“cacy beliefs also appear to be
important factors contributing to combination therapy adher-
ence (Catz, et al., 2000; Mostashari, Riley, Selwyn, & Altice,
1998). In an effort to identify other patient factors that could
help to account for missed dosages, several recent studies
also report on open-ended responses provided by patients
concerning reasons for missed dosages (see Catz et al., 2000;
Chesney et al., 2000; Weidle et al., 1999). •Simply for get-
tingŽ and confusion about the treatment regimen are cited
commonly as reasons for missed dosages, as are concerns
over side effects, and dif“culties in “tting complicated pill-
taking regimens into a daily routine. Many patients also raise
concerns about the psychological impact of being reminded
frequently of one•s disease, and fear that others will “nd out
that they are HIV-positive.