About the Program

Mission
The Asthma Adherence Pathway™ (AAP) seeks to improve adherence to asthma therapy and improve therapeutic outcomes by providing adherence educational services to patients and their families, as well as to providers and payers of care.

How the Program Works
Healthcare payers/administrators (e.g. HMOs, Medicare/Medicaid, self-insuring private companies, etc.) enroll in the AAP as a means of promoting asthma treatment adherence rates and improving the quality of life and productivity of their employees or subscribers.

Participating payers can enroll both patients (i.e. the payers’ subscribers or employees) and healthcare providers in the program. Enrolled parties are given codes allowing them to enter the password-protected part of the site.

Enrolled patients, upon the recommendation of their participating payer or provider, will go to the password-protected site to complete an online survey of their asthma history, symptoms, and treatment. The survey takes about ten minutes, and once it is finished, the patient can generate a printable summary of the issues and concerns raised. The results will also be available online to the participating provider, who will review the survey with the patient by appointment.

Enrolled providers can go to the password-protected site to review the results and recommended treatment strategies for a single patient survey. Providers can also examine the statistics yielded by select groupings of anonymous surveys. Additionally, providers will find that the password-protected site offers proven guidelines and practical strategies for helping their patients agree to and follow through with a cost-effective treatment plan.

Benefits
For patients and families: The program provides an opportunity to share concerns with healthcare providers who can use that information to help them control symptoms and improve quality of life by following an agreed-upon treatment program.

Physicians: The program provides a way to identify a patient's adherence; reasons for non-adherence to asthma therapy, and efficiently address those issues in a cost-effective manner.

Payers: The AAP program provides a disease management tool that enables providers to accurately diagnose and treat asthma; promotes adherence in a cost-effective manner; and reduces symptoms and improves the quality of life and productivity of their employees or subscribers. The AAP can also be accessed by multiple care givers or supervisers depending on the health care organization.

How To Participate
Patients or family members interested in participating in the Asthma Adherence Pathway program should contact their healthcare provider or their payer’s benefits administrator.

Healthcare payers or providers interested in the program should contact:

Dr. Andrew G. Weinstein
Asthma Management Systems
302 893 5455
info@asthma-ms.com

About Dr. Weinstein
Dr. Andrew G. Weinstein is a board-certified allergist and clinical immunologist and Associate Clinical Professor of Pediatrics at Thomas Jefferson Medical College.

He graduated from the University of Pennsylvania School of Medicine. He received his pediatric residency and allergy/immunology fellowship training at the Children’s Hospital of Philadelphia and the Hospital of the University of Pennsylvania. Dr. Weinstein completed two years of family therapy training at the Philadelphia Child Guidance Clinic. He is a Motivational Interviewing trainer having studied with Stephen Rollnick.

Dr. Weinstein has written extensively about asthma rehabilitation, medication adherence and psychosomatic asthma and is the  the principal author of more than 20 articles published in such journals as the Journal of Allergy and Clinical Immunology, the Annals of Allergy Asthma, and Immunology and The Journal of Asthma. He is a co-author of the asthma section of the 2003 World Health Organization report Adherence to Long Term Therapies: Evidence for Action. He has presented courses, workshops and seminars for physicians and allied health professionals at the Annual Meetings of the American Academy of Allergy Asthma and Immunology and the American College of Allergy Asthma and Immunology. He provides Adherence/Communication training for Pediatric, Family and Internal Medicine and Allergy/Immunology training programs as well as health plans. He developed the AsthmaPACT for the Asthma and Allergy Foundation of America which is the forerunner of the Asthma Adherence Pathway.

He is the chair of the Health outcomes Education Delivery and Quality Interest Section and the founding chair of the Adherence Committee of the American Academy of Allergy, Asthma and Immunology. Dr. Weinstein was the chair of the Medication Adherence Task Force of the Medical Society of Delaware and a past president of the Pennsylvania Allergy and Asthma Association.

About Dr. McQuaid
Elizabeth McQuaid's served as a consultant in developing the Asthma Adherence Clinical Pathway. Her current research interests focus on the psychosocial aspects of pediatric asthma, including adherence to pediatric asthma regimens across the adolescent transition and individual and family characteristics that influence pediatric asthma outcomes. She is current PI on two treatment trials to improve asthma management among low-income children, and a longitudinal study evaluating asthma management across the transition to high school. Dr. McQuaid is currently the Director of the Brown Clinical Psychology Training Consortium.

The Asthma Adherence Pathway is a result of more than 30 years of research and clinical practice. Dr Weinstein developed the area of Asthma Adherence Disease Management which requires four sequential components to be delivered to the patient. The first is is to diagnose the adherence status of the patient. Second, if the patient is non-adherent, identify the reason(s) why. Three, select strategies that are relevant to the patient’s concerns to improve adherence. And fourth, deliver the strategy in a way that will have an optimum effect, such as using Motivational Interviewing technique or other patient-centered communication programs

The Asthma Adherence Pathway was derived from the clinical treatment model developed at the Alfred I Dupont Hospital for Children Asthma Rehabilitation Program in Wilmington Delaware. It was subsequently applied to child and adult asthma patients in clinical practice and then placed on the Asthma and Allergy Foundation of America web site www.asthmaPACT.org. The treatment model has been shown to be effective in reducing hospitalization, emergency care and costs from severe asthma.

History and Development of the Program
By Dr. Andrew Weinstein

Like many physicians, I have been engaged in a career-long pursuit to improve the health of my patients. During my first year of pediatric residency at the Children’s Hospital of Philadelphia in 1973. I began to realize that many children with chronic diseases and their parents did not follow physicians’ treatment plans.

During my first six-week inpatient rotation, an adolescent boy with hemophilia (factor 8 deficiency), was admitted twice with his ankle and knee bleeding. When I first took his history, the cause of the trauma was a touch football game in the streets of South Philadelphia. His mother, a single parent, was frustrated that her son was not following the doctor’s common sense instructions: do not play games that can cause trauma. The hematology group was very concerned that the boy had developed antibodies to the factor replacement, compromising his treatment’s efficacy. Several weeks later, he was admitted again after "going for a deep out and I ran into the curb, but I held onto the ball for a touchdown." I was told by the attending, that the situation was very frustrating for the doctors and families, but there wasn’t much anyone could do about it.

As the two years of residency passed, the words of the attending rang true. Many children with a multiplicity of chronic diseases were being readmitted because the family -- and/or the child -- were not following an "effective" treatment plan. More importantly, no one was doing anything about it. During my residency, Salvador Minuchin M.D., a family therapist and author of Families and Family Therapy, and Lester Baker M.D., a pediatrician, were examining the relationship of stress, disease response, and family interaction (psychosomatics) at the Philadelphia Child Guidance Clinic (PCGC) and the Clinical Research Center of the Children’s Hospital of Philadelphia. They theorized that certain types of family interactions in children with anorexia nervosa, diabetes, and asthma were responsible for persistent symptoms that could lead to hospital admission. (Their theory was later published in Psychosomatic Families: Anorexia Nervosa in Context.1978)

I found this work very interesting and began to chart a career path that would include training in child psychiatry. I arranged a third year of pediatric residency at Hahnemann Hospital, which included six months of child psychiatry electives. Buoyed by my continued interest, I convinced Dr. Harold Lecks, the chairman of the allergy department at Children’s Hospital, to permit me to combine an allergy/clinical immunology fellowship with a family therapy training program, a once weekly evening extern program directed by Dr. Minuchin at the Child Guidance Clinic.

Dr. Minuchin's and colleagues’ family-therapy lectures and seminars gave me a framework to understand the structure and organization of families, spouse and child subsystems, and the adaptive and maladaptive ways families react to chronic childhood illness. Psychosomatic illness, including asthma, was part of the curriculum.
In 1982, I conducted a pediatric asthma adherence study at the Medical Center of Delaware’s pediatric clinic. I examined the effectiveness of the interventions I learned during my fellowship and measured adherence by prescribing theophylline and obtaining blood levels.

In 1985, I was asked to establish an inpatient asthma rehabilitation program at the Alfred I. duPont Institute in Wilmington. At that time the hospital’s goal was to become a full-service children’s hospital, shedding its image as a world-class orthopedic hospital for children.

The duPont Asthma Rehabilitation Program was organized around family involvement. Family members had to be willing to meet with our multidisciplinary team twice weekly for their child to be admitted. The team consisted of a pulmonologist, psychologist, social worker, gastroenterologist, physical therapist, nurse practitioner, primary nurse, and myself serving as allergist, clinical immunologist, and family therapist. From the beginning of the program, the goals for admission were to improve and maintain adherence with multiple drug and environmental recommendations and decrease or prevent psychosomatic asthma. We believed that nearly all asthma symptoms could be controlled if adherence and psychosomatic issues could be addressed.

We were interested in the most severely asthmatic children and their families. Most of the children/families were treated for 10-14 days. The hospital administrator was working with managed care, being very responsive to their concerns about cost. Our group continually revised our approach, made cuts to our program, and focused on what was essential for achieving adherence and preventing stress-induced asthma.

After discharge, the children and families were seen as outpatients with drug monitoring for adherence for most patients, since most were receiving theophylline as one of four to seven medications taken two to four times per day. Family sessions would continue as needed to improve adherence and reduce psychosomatic asthma.

In all, we cared for 59 consecutive patients with unusually good results. The median number of hospital days the year prior to admission for the group was seven; emergency care visits four. For each of the four years of follow-up the median number of hospital days and emergency visits was zero. Median total costs for asthma care the year prior to admission were $10,240. The costs during follow-up were:

  • Year one $4,036
  • Year two $2,801
  • Year three $2,316
  • Year four $1,936

These were significant savings, financially, for the health insurers. (Journal of Allergy and Clinical Immunology 1996; 101:264-73).

At several health plans’ requests we established a less expensive outpatient program that was designed to reduce hospitalization and emergency care but would be administered over five days. Family involvement with emphasis on adherence and psychosomatics were the key components. Eleven patients/families were treated with comparable, if not superior results, in that these children had more severe disease than the inpatient group (Journal of Allergy and Clinical Immunology 1998; 101:S178A).

What lessons might health policy makers learn from this body of work in developing a "better" treatment style for childhood asthma? A complete report can be found in the Final Report of the Medication Adherence Task Force, Weinstein, et. al (Del Med Jrl 2001; 73: 341-345), but the two most important points can be summarized as follows:
The first is that identifying adherence status can improve health and decrease medical costs secondary to hospital care. The data from the asthma rehabilitation program supports this claim. Non-adherence with treatments is an enormous problem affecting all areas of health care. It is estimated that 50% of patients do not follow medical advice.
The second is that physicians should have psychological, family systems, and communication training during medical school and residency training to help manage patients with chronic disease. These topics have been introduced in many medical schools. "Talking" appears to be an important part of healing. Physicians should not only be knowledgeable about an individual’s health needs. They should also be able to convey this information in a manner that encourages and motivates the individual to act responsibly. Using the family conference as a means to "activate" a plan can be helpful. Health policy makers may also want to train allied health professionals (e.g., nurses, educators) to carry out these tasks at significantly lower costs. Many of these individuals might be more sympathetic and interested than some physicians. The Asthma Adherence Pathway provides a survey for patients that was successfully used in the DuPont Asthma Rehabilitation Program. What is unique about the AAP is that it provides a disease management algorithm that connects the individual and unique concerns of a patient to recommended, proven guidelines that a physician can use to maximize patient adherence and outcomes.

Improving Adherence and Reducing Costs

The Problem
The human and financial costs for asthma care are considerable as mentioned above. Estimates for cost secondary to non-adherence have been as high $290 billion per year. With treatment, however, many of these costs are preventable.

EPR3 states that most asthma patients can be asymptomatic, with normal quality of life, if they take recommended anti-inflammatory medication, typically inhaled ICS.(1) But in practice, there is an unacceptably high level of preventable morbidity and mortality. Poor medication adherence (due largely to low motivation), poor inhaler technique and inadequate medication are major causes of treatment failure, but physicians have no practical tools to determine which are operative for a given patient.(2)

In out-patient studies, non-adherence rates for inhaled corticosteroids (ICS) range from 28%-56%.(3,4) Although there is no way to measure ICS adherence in patients who come to the ER due to an asthma exacerbation, most clinicians estimate that adherence is significantly lower than the outpatient findings above.(2) A 1979 study examining adherence to theophylline, a widely-used prophylactic medication of that era, found that only 2% of children had a therapeutic level when seen in the ER.(5) The investigators measured adherence with an assay used to determine therapeutic dose. This finding is consistent with studies that report only 8%-13% of patients continue to fill ICS prescriptions after one year.(3,4) Medication non-adherence is associated with increased symptoms,(6) ER visits,(7) hospitalizations(6) and use of oral steroids.(7)

One significant problem for clinicians attempting to follow EPR3 guidelines is the inability to accurately diagnose the adherence status of asthma patients.(2) Multiple studies have documented that many patients do not give a truthful report of medication use to physicians.(8,9) This is a critical problem for non-adherent (NA) patients with severe disease, since many who are not diagnosed as NA are seen in the ER and admitted to hospital and managed incorrectly, as if they were adherent, while the underlying cause of the symptoms, NA, goes unrecognized.(2) These patients are at risk for receiving excess medication, imaging, lab tests, office visits, ER visits, hospitalization and increased morbidity and mortality due to physicians? inability to diagnose the true cause of treatment failure,(2)

Increasing asthma knowledge through education yields little improvement in adherence or asthma outcomes.(10) Interventions that encourage patients to monitor symptoms or peak flow have shown significant but small effects on morbidity.(11) Self-management approaches, including identifying barriers to adherence, self-monitoring of medication, goal setting and problem solving result in fewer ER visits,(10) short-term improvements in adherence,(12,13) higher self-management self-efficacy,(14) improved QoL,(15) reduced symptoms,(12) and less beta-agonist use.(12) However, most self-management studies involved more than 5.5 hours of patient contact.(16)

The Solution
The Asthma Adherence Pathway™ allows patients to self-identify barriers to adherence and report non-adherence with medication prescribed. When adherence barriers are identified, specific strategies are recommended in combination with patient-centered communications skills such as motivational interviewing. This creates a non-judgmental atmosphere in which patients are comfortable discussing their true conflicts about adherence. These strategies help patients resolve ambivalence about medication and builds their intrinsic motivation.

Dr. Weinstein has preliminary validation data for both child and adult AAPs (see pdfs). He was a co-investigator in an NIH study Grant#7R44HL078252-05 which developed a brief (11 item) Adult Asthma Adherence Questionnaire which will help clinicians both identify patient and improve adherence status.(17) Dr. Weinstein continues to use electronic adherence monitors for inhaled corticosteroids to give feedback to promote adherence.

The rationale to monitor patients with severe persistent asthma was published by Dr. Weinstein in the February 2005 Annals of Allergy, Asthma and Immunology (see PDF). Dr. Weinstein has been successfull in using the AAP and electronic monitors for patients with severe asthma referred by Blue Cross Blue Shield of Delaware. Using this comprehensive and novel method the Asthma Monitoring Project was able to reduce asthma costs by 72% (Data on file BSBSDE). The AAP is now available for all clinicians caring for child and adult patients to promote adherence, reduce morbidity, enhance quality of life and reduce costs for care.

Conclusion
The healthcare industry has an unusual opportunity to improve care and reduce costs with a minimal investment. Health plans will save significant sums by reducing the frequency of hospital care. Pharmaceutical companies will increase sales of their products since individuals will be taking more of them. Physicians will be more productive and achieve more satisfaction in their practice by improving healthcare outcomes. Hospitals will be more efficient and reduce unnecessary admissions. This scenario can only be realized if clinicians can diagnose the adherence status and identify reasons for non-adherence. The Asthma Adherence Pathway™ is an online monitoring tool that helps physicians to do exactly that. It enables them to identify the existence of and likely reasons for non-adherent behavior, while offering the educational information, proven guidelines, and practical strategies that will help them promote adherence to asthma treatment plans.

References

(1) Guidelines for the Diagnosis and Management of Asthma, Expert Panel Report 3 (EPR3) 2007. NIH, NHLBI. August 2007. NIH publication no. 08-4051.

(2) Weinstein AG. Should patients with severe persistent asthma be monitored for medication adherence? Ann Allergy Asthma Immunol 2005;94:251-257.

(3) Bender BG, Pedan A, Varasteh LT. Adherence and persistence with fluticasone propionate/salmeterol combination therapy. J Allergy Clin Immunol 2006; 118:899-904.

(4) Marceau C, Lemiere C, Berbiche D, Perreault S, Blais L. Persistence, adherence, and effectiveness of combination therapy among adult patients with asthma. J Allergy Clin Immunol 2006;118:574-581.

(5) Sublett JL, Pollard SJ, Kadlec GJ, Karibo JM JM Non-compliance in asthmatic children: a study of theophylline levels in a pediatric emergency room population. Ann Allergy 1979 Aug;43(2):95-7.

(6) Bauman LJ, Wright E, Leickly FE, Crain E, Kruszon-Moran D, WadeSL, et al. Relationship of adherence to pediatric asthma morbidity among
inner-city children. Pediatrics 2002;110:e6

(7) Williams LK, Pladevall M, Xi H, Peterson EL, Joseph C, Lafata JE, et al.Relationship between adherence to inhaled corticosteroids and poor outcomes among adults with asthma. J Allergy Clin Immunol 2004;114:1288-93.

(8) Mawhinney H, Spector SL, Heitjan D, et al. As-needed medication usein asthma usage patterns and patient characteristics. J Asthma. 1993;30:61–71.

(9) Coutts JAP, Gibson NA, Paton JY. Measuring compliance with inhaledmedication in asthma. Arch Dis Child. 1992;67:332–333

(10) Ho J, Bender BG, Gavin LA, O’Connor SL, Wamboldt MZ, Walmboldt FS. Relations among asthma knowledge, treatment adherence, and outcome. J Allergy Clin Immunol 2003; 111: 498-502.

(11) Reddel H, Toelle BG, Marks GB, Ware SI, Jenkins CR, Woolcock AJ. Analysis of adherence to peak flow monitoring when recording of data is electronic. Thorax. 2007;62:741–742.

(12) Guevara JP, Wolf FM, Grum CM, Clark NM. Effects of educational interventions for self management of asthma in children and adolescents: systematic review and meta-analysis. BMI 2003; 326: 1308-9.

(13) Walders N, Kercsmar C, Schluchter M, Redline S, Kirchner HL, Drotar D. An interdisciplinary intervention for undertreated pediatric asthma. Chest 2006; 129: 292-9.

(14) Smith JR, Mildenhall S, Noble MJ, Shepstone L, Koutantji M, Mugford M, et al. The Coping with Asthma Study: a randomized controlled trial of a home based, nurse led psychoeducationl intervention for adults at risk of adverse asthma outcomes. Thorax 2005; 60: 1003-11.

(15) Cicutto L, Murphy S, Coutts D, O’Rourke J, Lang G, Chapman C, et al. Breaking the access barrier: evaluating an asthma centers’ efforts to provide education to children with asthma in schools. Chest 2005; 128: 1928-35.

(16) Cabana MD, Le TT. Challenges in asthma patient education. J AllergyClin Immunol 2005;115:1225-7

(17) Weinstein AG, Schatz M, Zeiger R, Turner-Bowker D, Saris-Blagma R and Cabin T Developing An Adult Asthma Adherence Questionnaire Ann of Allergy Asthma Immunol 2011;107:A35

       
 

Quick Facts About Asthma

The National Institutes of Health Asthma Fact Sheet estimates that:

 
       
 

12-15 million Americans suffer from asthma, including 4.8 million children under age 18

 
       
 

• Asthma is the most common chronic childhood disease, affecting more than one child in 20

 
       
 

Among children ages 5 to 17, asthma accounts for an annual loss of more than 10 million school days each year

 
       
 

For adults, asthma is the fourth leading cause of work loss resulting in nine million lost workdays each year.

 
       
 

There are approximately 1.8 million emergency room visits per year for asthma.

 
       
 

Asthma results in approximately 500,000 hospitalizations per year.

 
       
 

In 1995, 5,637 individuals died from asthma.

 
       
 

Every day in America:

 
       
 

40,000 people miss school or work due to asthma.

 
       
 

30,000 people have an asthma attack.

 
       
 

5,000 people visit the emergency room due to asthma.

 
       
 

1,000 people are admitted to the hospital due to asthma.

 
       
 

11 people die from asthma.

 
       
 

PREVELANCE

 
       
 

An estimated 20 million Americans suffer from asthma (1 in 15 Americans), and 50% of asthma cases are “allergic-asthma.” The prevalence of asthma has been increasing since the early 1980s across all age, sex and racial groups. [1]

 
       
 

Nearly 5 million asthma sufferers are under age 18. It is the most common chronic childhood disease, affecting more than one child in 20. [2]

 
       
 

Asthma is slightly more prevalent among African Americans than Caucasians. [3]

 
       
 

Ethnic differences in asthma prevalence, morbidity and mortality are highly correlated with poverty, urban air quality, indoor allergens, and lack of patient education and inadequate medical care.

 
       
 

MORBIDITY

Asthma accounts for one-quarter of all emergency room visits in the U.S. each year, with 2 million emergency room visits. [4]

 
       
 

Each year, asthma accounts for more than 10 million outpatient visits and 500,000 hospitalizations. [5]

 
       
 

The average length of stay (LOS) for asthma hospitalizations is 3 days. [6]

 
       
 

Asthma is the #1 cause of school absenteeism among children accounting for more than 14 million total missed days of school. [7]

 
       
 

Mortality

 
       
 

Each day 11 Americans die from asthma. There are more than 4,000 deaths due to asthma each year, many of which are avoidable with proper treatment and care. [8]

 
       
 

African Americans are three times more likely to die from asthma. African American Women have the highest asthma mortality rate of all groups, more than 2.5 times higher than Caucasian women [9] Social and Economic Costs

 
       
 

Social and Economic Costs

 
       
 

The annual cost of asthma is estimated to be nearly $18 billion.

 
       
 

Direct costs accounted for nearly $10 billion (hospitalizations the single largest portion of direct cost) and indirect costs of $8 billion (lost earnings due to illness or death). [10]

 
       
 

For adults, asthma is the fourth leading cause of work absenteeism and “presenteeism,” resulting in nearly 15 million missed or lost ("less productive") workdays each year (this accounts for nearly $3 billion of the "indirect costs" shown above). [11]

 
       
 

Among children ages 5 to 17, asthma is the leading cause of school absences from a chronic illness. It accounts for an annual loss of more than 14 million school days per year (approximately 8 days for each student with asthma) and more hospitalizations than any other childhood disease. It is estimated that children with asthma spend an nearly 8 million days per year restricted to bed. [12]

 
       
 

Disparities

 
       
 

ETHNIC

 
       
 

African Americans are three times more likely to be hospitalized from asthma. [13]

 
       
 

African Americans are three times more likely to die from asthma. [9]

 
       
 

GENDER

 
       
 

More females die of asthma than males, and women account for nearly 65% of asthma deaths overall. [14]

 
       
 

African American women have the highest asthma mortality rate of all groups, more than 2.5 times higher than Caucasian women. [9]

 
       
 

AGE

 
       
  Among children ages 5 to 17, asthma is the leading cause of school absences from a chronic illness. It accounts for an annual loss of more than 14 million school days per year (approximately 8 days for each student with asthma) and more hospitalizations than any other childhood disease. It is estimated that children with asthma spend an nearly 8 million days per year restricted to bed. [12]  
       
 

For adults, asthma is the fourth leading cause of work absenteeism and “presenteeism,” resulting in nearly 15 million missed or lost workdays each year, resulting in a total cost of nearly $3 billion in total lost productivity. [11]

 
       
 

References

 
       
 

[1] “Asthma at a Glance,” National Center for Environmental Health (NCEH), U.S. CDC, 1999

 
 

[2] “Morbidity and Mortality Report,” NCHS, U.S. CDC, 2003

 
 

[3] “Asthma: A Concern for Minority Populations,” NIAID, NIH 2001

 
 

[4] “New Asthma Estimates: Tracking Prevalence, Health Care and Mortality,” NCHS, CDC, 2001

 
 

[5] “New Asthma Estimates: Tracking Prevalence, Health Care and Mortality,” NCHS, CDC, 2001

 
 

[6] “National Hospital Discharge Survey,” NCHS, U.S. CDC, 2000

 
 

[7] “Condition of Education,” NCES, U.S. Department of Education 2001

 
 

[8] New Asthma Estimates: Tracking Prevalence, Health Care and Mortality,” NCHS, CDC, 2001

 
 

[9] “Asthma: A Concern for Minority Populations,” NIAID, NIH 2001

 
 

[10] “The Costs of Asthma,” Asthma and Allergy Foundation 1992 and 1998 Study, 2000 Update

 
 

[11] “Morbidity and Mortality Weekly Report,” Surveillance for Asthma, U.S. CDC, 2002

 
 

[12] “The Costs of Asthma,” Asthma and Allergy Foundation 1992 and 1998 Study, 2000 Update

 
 

[13] “Asthma: A Concern for Minority Populations,” NIAID, NIH 2001

 
 

[14] “New Asthma Estimates: Tracking Prevalence, Health Care and Mortality,” NCHS, CDC, 2001