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Caring for the Adult With Sickle Cell Disease:
Results of a Multidisciplinary Pilot Program
Nicole Artz, MD; Chad Whelan, MD; Sharon Feehan, DNP, FNP-BC
Background: Care for adults with sickle cell disease (SCD) is
often fragmented and costly. The chronic care model is recommended as a best practice approach to providing care
for patients with chronic disease. However, no published
reports exist examining the effectiveness of this approach in
adults with SCD.
Purpose: To examine selected quality and utilization measures at baseline and following implementation of a new
multidisciplinary program for adults with SCD at one academic institution.
Methods: Administrative data were obtained for all adults
with SCD admitted to the adult emergency department or
hospital or seen in the adult outpatient clinic during calendar years 2000-2009. Charts of all patients seen in the adult
multidisciplinary sickle cell clinic were abstracted using prespecified criteria.
Results: Prescribing of hydroxyurea increased from 13% at
baseline to 44%. An additional 53% of patients had a documented reason for no prescription. Decreases in admissions,
30-day readmissions, and lengths of stay resulted in an average savings of 458 bed days per year.
Conclusion: Multidisciplinary care for the adult with SCD provided in the context of the chronic care model can result
in significant improvements in important quality targets and
may reduce acute resource use.
Keywords: sickle cell disease n utilization
J Natl Med Assoc. 2010;102:1009-1016
Author Affiliations: Department of Medicine, Loyola University Health
System (Drs Artz and Whelan); and Department of Medicine, University of
Chicago Medical Center (Ms Feehan), Chicago, Illinois.
Correspondence: Nicole Artz, MD, Department of Medicine, Loyola
University Health System, 2160 S First Ave, Bldg 54, 007, Maywood, IL 60153
(nicoleartz@sbcglobal.net).
Introduction
S
ickle cell disease (SCD) is an inherited, chronic
disorder affecting multiple different organ systems and resulting in significant morbidity and
early mortality. Due to advances in early diagnosis and
treatment, more than 90% of children with the disease
now live into adulthood, placing a growing strain on
JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION
the health care delivery system.1 Data from Agency for
Healthcare Research and Quality show that the estimated cost for SCD hospitalizations in 2004 was $488
million and adults comprised nearly 75% of hospital
admissions.2 Unfortunately, care for adults with SCD
remains fragmented and fraught with mistrust between
patients and health care providers. 3-7 In addition, that
no centralized database for reporting quality measures
exists and what little published data are available suggests the majority of patients are not receiving recommended care.8-10
A multidisciplinary approach to care using the
chronic care model has been shown to be effective in
reducing utilization in patients with asthma, congestive
heart failure, and diabetes; to improve quality outcomes
in patients with diabetes;11 and is recommended as a best
practice approach to caring for patients with SCD by
organizations in both Britain and the United States.9,12
The chronic care model, as described by Wagner, has 6
components including: (1) community resources and
policies, (2) health care organization, (3) self-management support, )4) delivery system design, (5) decision
support, and (6) clinical information systems.13-16 This
approach seems ideally suited to addressing the multiple
challenges in providing care for this population.
However, to our knowledge, no published reports exist
examining the effectiveness of this approach in adults
with SCD. The focus of much of the prior work on SCD
in adults is on resource utilization and clinical outcomes.
We set out to examine selected quality of care measures
and acute health care utilization at baseline and following implementation of a new multidisciplinary care
team incorporating components of the chronic care
model for adults with SCD.
Methods
This is a prospective observational study designed to
assess pre- and postintervention quality and administrative outcomes of a new multidisciplinary adult sickle
cell treatment program initiated in October 2006 at an
academic tertiary care medical center on the south side
of Chicago. This study was approved by the institutional
review board.
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Multidisciplinary Care for Adults with Sickle Cell
Description of the Program
The adult sickle cell care team is comprised of a physician director, a nurse practitioner, and a licensed clinical social worker. The program uses a multidisciplinary
care approach to ensure continuity across the spectrum
of health care delivery. The components of the chronic
care model which were incorporated in the program are
denoted in parentheses.
Setting
The program was initiated at an academic tertiary
care medical center located on the south side of Chicago.
An average of 280 to 300 unique adults with SCD have 1
or more encounters per year at the institution. The payer
mix is approximately 60% Medicaid and 30% Medicare,
with the remaining a mix of private and uninsured. The
program was developed by an internist physician champion with broad support from many divisions, including
hematology, emergency medicine, anesthesia pain, nursing, and social work. It was funded through the
Department of Medicine with the goals of improving
care delivery, reducing need for acute resource use, and
Figure 1. Hospital Admissions at the Institution by
Year for All Adults With Sickle Cell Disease
advancing opportunities for meaningful research (chronic
care model component: health care organization).
Adult Sickle Cell Care Team
Physician director. The physician director is a practicing internist with training and board certification in
internal medicine and pediatrics. Twenty-five percent of
the physician’s time is dedicated to direct patient care and
to oversight of the program. The physician sees patients
in the outpatient clinic one-half day per week and is
responsible for training and clinical supervision of the
advanced practice nurse (chronic care model component:
delivery system design). Administrative responsibilities
include program budget management, coordination with
researchers to initiate basic science and clinical research,
and tracking administrative and quality data.
Nurse practitioner. The nurse practitioner provides
consultation for hospitalized patients assisting with treatment of pain, early recognition and management of lifeor organ-threatening complications, decisions regarding
need for blood transfusion, and discharge planning
(chronic care model component: delivery system design).
She serves as an advocate for the patient and works with
the health care team to educate and reduce mistrust. In
addition, she sees patients 2 half-days per week in
Figure 2. Hospital Admissions at the Institution
per Patient by Year for All Adults With Sickle Cell
Disease
Figure 3. Hospital Admissions by Month
Figure 4. Ongoing Reduction in 30-Day
Readmissions at the Institution by Year for All
Adults With Sickle Cell Disease
There was large variability in admissions prior to initiation
of the adult sickle cell program. There seems to be a
lower baseline with less variability after initiation of the
multidisciplinary program.
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Multidisciplinary Care for Adults with Sickle Cell
an outpatient clinic. The remainder of her time is spent
providing case-management services (chronic care
model component: delivery system design). Patients are
encouraged to call the nurse practitioner’s voice mail to
leave their prescription refill requests prior to running
out, thus avoiding the cycle of running out of adequate
analgesics for use at home, which may precipitate withdrawal, escalation of pain, and an otherwise unnecessary
trip to the emergency department (chronic care model
component: self-management support).
Social worker. The licensed clinical social worker
addresses the psychosocial needs of patients. In addition
to assisting with concrete needs (transportation, housing, utilities), her role includes helping patients identify
triggers for their vasocclusive crises, teaching patients
about nonmedicinal pain management techniques that
they can implement themselves, and providing cognitive
behavioral therapy when needed to reframe negative
thought patterns (chronic care model components: selfmanagement support and delivery system design). She
actively connects patients with community resources,
including local sickle cell organizations, vocational
training programs, mental health services, and coordinates support group meetings (chronic care model component: community resources and policies).
Additional services. All patients have access to a
provider via a 24-hour emergency pager. Patients are
taught to page the providers for assistance with treating
their crisis pain at home and advice regarding when to
go to the emergency department (chronic care model
component: self-management support). The care team
worked with the emergency department and inpatient
nursing leadership to develop an evidence-based crisis
treatment protocol, inpatient standardized order set, and
to obtain new patient controlled analgesia pumps for the
wards capable of delivering adequate analgesia for
patients with high opioid tolerance (chronic care model
component: decision support). All members of the care
team provide ongoing formal and informal education to
patients, physicians, nurses, and ancillary staff and
actively work to reduce misperceptions about drugseeking behavior and risk of addiction (chronic care
model component: self-management support). In the
rare event that a patient’s behavior is interfering with the
ability to provide them with safe and effective care, a
care plan is developed which offers structured behavioral guidance with consequences for deviations from
the plan so a positive and safe provider-patient relationship can be maintained. Care plans were necessary for
approximately 10 out of 157 patients.
Figure 6. Total Bed Days per Year
Figure 5. Inpatient Average Lengths of Stay (Days)
by Year for All Adults With Sickle Cell Disease
This figure shows a decrease in inpatient bed days for all
adults with sickle cell disease. The new multidisciplinary
program was initiated in October 2006.
Figure 7. Total Bed Days per Patient
This figure shows that total number of bed days per
patient were decreased in the years since initiation of the
multidisciplinary program and are at the lowest they have
been in the past 10 years in 2009.
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Figure 8. Total Bed Days by Month
There was large variability in inpatient bed days prior to
initiation of the adult sickle cell program.
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Multidisciplinary Care for Adults with Sickle Cell
Quality of Care Measures
All patients with a confirmed diagnosis of SCD who
were seen at least once in the multidisciplinary adult
sickle cell clinic were included for purposes of quality
of care measurement. Because we did not have a clinical
information system which we could use to abstract process measures, quality measures were obtained by individual chart review using specific criteria as explained
below. Unless otherwise specified, we chose to include
all patients with at least 1 visit to our outpatient clinic as
the denominator. Patients who were “actively followed”
were defined as those with at least 1 visit within the past
12 months.
Hydroxyurea. Hydroxyurea is currently the only
FDA-approved medication available for treatment of
SCD. It has been shown to significantly reduce the incidence of painful crises, acute chest syndrome, and mortality.17,18 It is widely believed that this medication is
underused in this population, but actual data on use are
lacking.8,19 We set out to determine the percentage of
patients who reported actively being prescribed hydroxyurea at the time of their first clinic visit with us, our
internal rate of prescribing, and our rate of documenting
an appropriate reason in patients who met severity criteria but were not prescribed the medication. Appropriate
Figure 9. Total Cost of Care of Inpatient
Hospitalizations by Year
Cost of inpatient care for adults with sickle cell disease was rising
prior to initiation of the dedicated multidisciplinary adult program
in October 2006. Since initiation of the program, cost of inpatient
care has been down approximately $1 000 000 per year.
reasons for not prescribing hydroxyurea included pregnancy or plans to get pregnant, hemoglobin SC disease,
patient refusal, and documented severe adverse reactions to the medication. Patients with mild disease and
those who came to clinic only once but did not return
were also included in the “reason documented” group
since we rarely initiate hydroxyurea on the initial visit.
Proteinuria. Nephropathy is a common complication of SCD occurring in up to one-third of adolescents
and adults.20,21 As with diabetic nephropathy, proteinuria
is an early sign of glomerular damage and responds to
treatment with an angiotensin-converting enzyme
(ACE) inhibitor.20,22 We defined proteinuria as a random
urine protein/creatinine ratio greater than 0.1 mg/dL on
2 or more measurements. We used a cut off of more than
0.2 mg/dL on 2 or more measurements to begin treatment with an ACE inhibitor or angiotensin receptor
blocker.
Vaccinations. Pneumovax and influenza vaccinations are recommended for all adults with SCD. We
measured our rate of either vaccinating patients with
pneumovax and for seasonal influenza or documenting
Figure 10. Total Hematology Outpatient Visits by
Year to the Adult Hematology Clinic or Infusion
Center for All Adults With Sickle Cell Disease
Figure 12. Hydroxyurea Use Pre and Post
Dedicated Adult Sickle Cell Program (n = 157)
Figure 11. Total Unique Adults With Sickle Cell
Disease by Year
Number of unique adults with sickle cell disease with 1 or
more encounters at the institution by year. The numbers have
been relatively stable since 2003.
1012 JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION
Only 13% of patients reported being on hydroxyurea at their
initial visit to the adult clinic. Forty-four percent of all patients
with 1 or more visits were prescribed hydroxyurea at the time
of their most recent clinic visit.
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Multidisciplinary Care for Adults with Sickle Cell
an appropriate reason for lack of vaccination. We considered the pneumovax to be up to date if it was given
with the prior 5 years.
Screening echocardiograms. Pulmonary hypertension is an increasingly recognized problem affecting
30% to 40% of adults with SCD, with a median survival
of 25.6 months from time of diagnosis.23,24 We chose to
investigate our rate of obtaining echocardiograms in
steady state within 2 years of the most recent visit.
Iron overload. Many patients with SCD develop
iron overload due to multiple blood transfusions throughout their life. We investigated our rate of screening for
iron overload. We defined iron overload as a steady-state
serum ferritin greater than 1000.
Administrative Data
All International Classification of Diseases, Ninth
Revision (ICD-9) codes for sickle cell disease (282.60,
282.62, 282.61, 282.42, 282.64, 282.69, 282.68, 282.63,
282.41) were used to pull encounters for the
administrative data analysis. Patients admitted to the
adult emergency department or hospital or seen in the
adult outpatient clinics were included. Data were
included for calendar years 2000-2009 in order to establish a baseline prior to initiation of the new program in
October 2006.
Statistical Testing
Descriptive statistics were used for resource utilization, adherence to quality measures, and patient volume.
Changes in resource utilization were assessed using
2-tailed unpaired t test and differences in adherence to
quality measures were assessed using c2 testing.
Results
One hundred fifty-seven patients had at least 1 visit
to the clinic. Of those patients, 66% were female, 64%
Figure 14. Influenza Vaccination Rates by Year
Figure 13. Postprogram Totals of Current
Hydroxyurea Missed Opportunities (n = 157)
This figure represents our rate of “missed opportunities” those
patients for whom we either prescribed hydroxyurea or who
documented a reason for not prescribing.
Figure 15. Iron Overload (n = 157)
This figure shows our rate of screening using the steady-state
serum ferritin. Thirty-right percent of screened patients met
criteria for iron overload, but only 8% of those reported being
on chelation therapy at their initial visit.
JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION
This figure represents where we are meeting our quality
targets of either vaccinating for influenza during flu season or
documenting a reason for no vaccination.
Figure 16. Missed Opportunity (n = 53)
This figure represents the percentage of patients who
met criteria for iron overload whom we failed to treat or
document a reason for no treatment.
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had hemoglobin SS, 15% had sickle ß-thalassemia, and
20% had hemoglobin SC disease. The average age was
31 years with a median of 27.5 years.
Administrative Outcomes
Figures 1 to 10 show changes in resource utilization.
There is a downward trend in admissions, 30-day readmissions, and lengths of stay, resulting in an average
savings of 458 bed days per year (average bed days for
years 2000-2006 compared with average bed days for
years 2007-2009, p value = .06 [-35.08 to 950.13]) and
concurrent reductions in cost of care. In the most recent
calendar year, 2009, we see the lowest number of admissions, 30-day readmissions, and total bed days of the
past nine years. Figures 3 and 8 show large variability in
admissions and total bed days in the years prior to the
program. There appears to be less variability since initiation of the program. The overall number of unique
patients treated at the institution was similar in the year
immediately before and after initiation of the program
(Figure 11).
Quality Outcomes
Hydroxyurea. Only 20 (13%) of patients reported
being on hydroxyurea at their initial visit to the clinic. Of
those, only 3 (15%) reported being on a dose consistent
with their goal dose. As of the last clinic visit, 44% of
patients with 1 or more visits to the clinic were prescribed hydroxyurea (Figure 12, p < .001). Of those, 41%
had been titrated to their maximally tolerated dose and
the remainder were being actively titrated. An additional
53% of patients did not meet criteria for hydroxyurea or
had a clearly documented reason for no prescription.
Thus, in this measure we met our quality target (prescribing in patients who met criteria or documenting a reason
for not prescribing) 97% of the time (Figure 13).
Proteinuria. One hundred thirteen patients (72%)
had been screened for proteinuria as of the last clinic
note. Fifty-three patients (47%) met criteria for proteinuria. Of the patients with proteinuria, we met our quality
targets in either treating with an ACE inhibitor or angiotensin receptor blocker or documenting a reason for no
treatment in 85% of patients.
Vaccinations. We documented an up-to-date pneumovax in 92 patients (59%) and documented a reason
for a lack of pneumovax in an additional 11 patients,
leaving us with a missed opportunity of 44%. Our rate of
influenza vaccination showed significant variability
from season to season (Figure 14).
Screening echocardiograms. Only 45% of patients
had an echocardiogram completed within the past 2 years.
Iron overload. One hundred thirty-eight patients
with 1 or more visits (88%) had a steady-state screening
serum ferritin. Of those, 53 (38%) qualified as having
iron overload. Only 8% of patients who qualified as having iron overload reported being on chelation therapy at
1014 JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION
the time of their initial visit to the multidisciplinary
clinic (Figure 15) vs 53% who were prescribed chelation
as of their last clinic visit (p < .001). An additional 21
(40%) had a clearly documented reason for no chelation
or had only 1 visit to the clinic. Thus, we met our quality
target for screening in 88% of patients and for treating in
92% of patients, leaving us with a “missed opportunity”
for treatment in 8% of patients with iron overload
(Figure 16).
Met all quality targets. We met all of our quality
targets in only 16% of patients.
Discussion
We present these results with the intent of starting an
open conversation about the state of care for adults with
SCD. Our results show that baseline quality of care was
poor and inpatient utilization at our institution was high
and rising. We suspect that this is the case at other institutions nationwide, although we cannot say this with
certainty, given the lack of available published information. Although we showed significant improvements in
quality measures such as prescribing hydroxyurea in
appropriate patients and screening and treatment for
iron overload, we note that even with a dedicated team
we were able to meet all quality targets in only 16% of
patients. Although some of the gap undoubtedly lies
with patients who made only 1 clinic visit or did not follow through with tests that were ordered, it is likely that
a greater portion lies in a lack of a systematic way of
tracking and automating these targets. The sixth component of the chronic care model, clinical information systems, was a challenge for us. Without an electronic medical record we did not have an automated reminder
system prompting us to follow through on missing quality measures. A major barrier to obtaining echocardiograms was the lack of reimbursement by insurance companies for purposes of screening. This was a frustrating
barrier to encounter, given the high prevalence of pulmonary hypertension in adults and the implications for
prognosis.
Our study has some important limitations to acknowledge. In regard to the quality measures, in the absence of
clear national or international guidelines, we chose to
focus on a few measures that we felt were most strongly
supported by data (ie, hydroxyurea and vaccinations), as
well as those that we felt had consensus among sickle
cell providers. We acknowledge that there are other
important measures that we did not track. We also
acknowledge the important limitations of using serum
ferritin as the main measure of iron overload. However,
this is the screening test that was available at our institution (an academic tertiary care center) at the time the
program was initiated, and we suspect it remains the test
most frequently used by the majority of physicians caring for these patients. We hope that in the future more
sophisticated, cost-effective, and noninvasive screening
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Multidisciplinary Care for Adults with Sickle Cell
methods for iron overload will be widely available.
This study was not designed to measure compliance
with treatment. Thus, we only measured and reported
those pieces of the process measures that we could
directly control. Nonetheless, we believe this is an
important first step. It is hard for a patient to be compliant with hydroxyurea if it has never been discussed and
prescribed.
This study was not a randomized, controlled trial and
thus any conclusions drawn about cause and effect are
purely speculative. This is particularly important to
remember when looking at our administrative data.
Reorganization of the general medicine and hematology
inpatient services happened concurrently and resulted in
all adult sickle cell patients being admitted to general
medicine; previously, patients could be admitted to the
general medicine or hematology service. In many ways,
this restructuring of the services worked in our favor,
allowing us to focus our inpatient quality improvement
and nursing education efforts on 1 unit and have more of
a physical presence during the day. However, a concurrent reduction in the number of general medicine beds
available contributed to overcrowding in the emergency
department and may have impacted emergency department utilization and admission rates. One may wonder if
the decrease in admissions simply reflects a decrease in
number of patients with SCD at our institution. However,
the total number of unique adults with SCD cared for at
our institution has been relatively stable between 2003
and 2009. Thus, we cannot explain the drop in admissions by a drop in total number of patients. Likewise, we
did not see a massive influx of new patients to the institution resulting in a greater number of individual patients.
Not all patients with SCD seen 1 or more times at the
institution chose to follow with our care team in the
clinic. We deliberately included all patients with SCD
(even those that did not follow with us in our clinic) for
purposes of administrative data analysis for several reasons. First, our goal was to improve care for all patients
with SCD and thus we were heavily involved in broad
quality improvement initiatives within the emergency
department and hospital wards such as obtaining highconcentration opioid patient controlled analgesia pumps,
developing standardized protocols, and participating in
nursing and house staff education. In addition, we consulted on any patient with SCD in the hospital, not just
those who followed with us in the clinic and likely
impacted acute resource use in these patients as well.
Finally, this study was not designed to look at overall
cost effectiveness. However, we suspect that the costs of
maintaining a program such as this are far offset by
improvements in quality of care delivered and reduced
need for acute resource use.
Our results show that significant improvements in
important quality targets can be accomplished in a relatively short period of time and suggest that
JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION
multidisciplinary care in the context of the chronic care
model may also reduce the need for acute resource use.
We assert that programs that specialize in caring for
patients with SCD, whether small or large, should
develop ways (ideally, electronic) of tracking and reporting their quality and administrative outcomes. We hope
that a centralized repository in which to track quality
and administrative outcomes will become available in
the future. This would allow programs to benchmark
their outcomes against those of similar programs and
share information in ongoing efforts to improve care
delivery for this vulnerable population.
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