Economic Evidence for U.S. Asthma Self-Management Education and Home-Based Interventions

Abstract

The health and economic burden of asthma in the United States is substantial. Asthma self-management education (AS-ME) and home-based interventions for asthma can improve asthma control and prevent asthma exacerbations, and interest in health care-public health collaboration regarding asthma is increasing. However, outpatient AS-ME and home-based asthma intervention programs are not widely available; economic sustainability is a common concern. Thus, we conducted a narrative review of existing literature regarding economic outcomes of outpatient AS-ME and home-based intervention programs for asthma in the United States. We identified 9 outpatient AS-ME programs and 17 home-based intervention programs with return on investment (ROI) data. Most programs were associated with a positive ROI; a few programs observed positive ROIs only among selected populations (e.g., higher health care utilization). Interpretation of existing data is limited by heterogeneous ROI calculations. Nevertheless, the literature suggests promise for sustainable opportunities to expand access to outpatient AS-ME and home-based asthma intervention programs in the United States. More definitive knowledge about how to maximize program benefit and sustainability could be gained through more controlled studies of specific populations and increased uniformity in economic assessments.

In the United States, asthma affects >22 million persons and costs approximately $63 billion annually.^{1, 2} Uncontrolled asthma is common in this population, affecting 50% of adults and 38% of children.³ Moreover, estimates indicate asthma-related emergency department (ED) visits and hospitalizations account for 30% of expenditures.² Together, these data suggest ample opportunity to improve asthma control and prevent asthma exacerbations, which could reduce the economic burden of asthma.

Certainly, uncontrolled asthma is multifactorial.³ Access and adherence to medical care consistent with the 2007 National Asthma Education and Prevention Program Guidelines for the Diagnosis and Management of Asthma (EPR-3) are fundamental.^{4, 5} In the EPR-3, complementary key components of asthma management include asthma self-management education (AS-ME) at multiple points of care, as well as control of environmental factors. Moreover, individually tailored, multi-faceted home-based interventions are recommended as a means to provide AS-ME and/or reduce environmental asthma triggers for specific populations.⁴

Despite the EPR-3 and growing emphasis on prevention and health care-public health collaboration in the United States^{4, 6–8}, there is limited availability of AS-ME outside of the traditional physician’s office visit (hereafter referred to as “intensive AS-ME”⁴; examples include AS-ME provided through a group class or an individual visit dedicated to asthma education with an allied health professional) and home-based intervention programs (e.g., programs offering individually tailored education or assistance regarding environmental trigger reduction in the home).^{4, 7, 9–11} Economic sustainability is a common concern.^{10, 12} Improved understanding of these programs’ economic implications could be useful to clinicians, health care administrators, public health officials, policy makers, investigators, and others considering such programs for the outpatient or home setting.

Thus, this review examines existing literature regarding economic outcomes reported for intensive outpatient AS-ME or home-based intervention programs for asthma in the United States.

Review Approach

For this narrative review, the following databases were searched in January 2016 for studies on asthma-related education or home-based intervention programs (heretofore referred to as “programs”) with cost or economic data (see Table E1 in the Online Repository for a complete list of search terms and strategies): PubMed/Medline (1946–present), Embase (1947–present), Cochrane Library (1800–present), and CINAHL (1981–present). Other relevant articles were identified through manual searching of articles’ reference lists. Similar search terms were used to conduct an online search of non-peer-reviewed materials (e.g., white papers, publicly available websites) and identify additional documents for reference list review. No data were obtained through personal communication.

Inclusion criteria were: (1) the program included provision of intensive outpatient AS-ME or ≥1 asthma-related home visit; (2) the program was provided to persons with asthma (i.e., tertiary prevention rather than primary or secondary prevention); (3) the program was conducted in the United States; and (4) asthma-specific data on return on investment (ROI) or calculated cost savings (positive or negative) were reported. Disease management programs met the first inclusion criterion if intensive outpatient AS-ME or ≥1 asthma-related home visit was specifically mentioned as a program component.

Exclusion criteria were: (1) the program was restricted to an inpatient, ED, school, residential camp, or military setting; (2) the program description mentioned “asthma education” without specifying AS-ME; or (3) reported ROI or cost savings data did not include asthma-specific calculations.

Abstracted data included program participants, personnel, components, health care utilization outcomes (i.e., utilization of medical care for asthma), and economic outcomes (i.e., ROI or calculated cost savings [positive or negative]). Given this review’s focus, the program sample sizes presented herein are those used to calculate ROI or cost savings; these might have differed from the total number of persons who participated.

A descriptive analysis was performed using Microsoft Excel. Programs that offered both intensive outpatient AS-ME and ≥1 asthma-related home visit were classified as asthma-related home visit programs. Also, programs were stratified by whether a benefit-cost ratio (i.e., ROI) was explicitly reported, because it could not be ascertained if calculations of cost savings without accompanying ROI data consistently included program operating costs.

Intensive Outpatient AS-ME Programs

We identified 9 U.S. programs that provided intensive outpatient AS-ME and reported ROI (Table I).^13–32 All but one were reported in peer-reviewed literature.¹⁵ An additional 18 U.S. programs providing intensive outpatient AS-ME reported cost savings without ROI data (Table E2).

Table I.

U.S. Programs With Return On Investment Data For Intensive Outpatient Asthma Self-Management Education (AS-ME), By State^a

State: Program (Dates)	Reference	Participants (Nb); Health Insurance Sector	Intervention(s); Personnel; Program Cost	Health Care Utilization Outcomec	Economic Outcomec	Study Design
Arkansas: Arkansas Foundation for Medical Care Quality Enhancing Intervention (2004–present)	Peer- reviewed journal:13 Other:14	Adults and children with asthma (aged 4–30 years) with ≥2 ED visits or hospitalizations (227); Medicaid	•AS-ME:   regular phone   calls •case   management •linkage to   subspecialty   care (if   indicated); nurse; total of $43,534 in baseline year, then $63,958 in year 1, $21,772 in year 2	↓ ED visits	ROI: $6.35 per $1 Time to realize ROI: 3 years	Pre– post
California: Asthma Tools and Training Advancing Community Knowledge (2008–2011)	Peer- reviewed journal: N/A Other:15	Children aged 1–18 years with asthma and ED visit (NR); Medicaid or Medicaid MCO	•AS-ME:   individual   session in   clinic •linkage to PCP •medical exam   in specialty   clinic •additional   services or   supplies (if   indicated, e.g.,   education on   spacer or   nebulizer use,   free asthma   medication   and spacer,   referral to   Asthma Start   program for   home visit [see   Table III]);   asthma   educator, nurse,   physician;   total of $32,000   in 3 years	No change in health care utilization (outpatient, ED, hospital, pharmacy)	ROI: <$1 per $1 Time to realize ROI: 3 years	RCT
Illinois: Pediatric Asthma Intervention (1999–2002)	Peer- reviewed journal:16 Other:17	Children aged ≤16 years with asthma (212); commercial insurance, Medicaid	Three AS-ME interventions: •Group 1 (G1):   AS-ME in 1   group session   (~20 minutes)   + individual   AAP •Group 2 (G2):   G1   intervention +   phone access   to asthma   educator   •Group 3 (G3):   G2   intervention +   case   management; CHW, nurse; $94/child for G1, $141– 155/child for G2, $389– 663/child for G3	Average among G1–G3: ↓ ED visits by   64% ↓ hospitalizations   by 81% ↓ outpatient visits   by 58%	G1 ROI: $43.64 per $1 G2 ROI: $27.66– $30.46 per $1 G3 ROI: $7.79–$13.29 per $1 Time to realize ROI: 2 yearsd	Pre– post
Massachusetts: Asthma Outreach Program (circa 1993)	Peer- reviewed journal:18–20 Other:21	Children aged 1–15 years with asthma and ED visit, hospitalization, or physician referral (65 [control=32, intervention= 33]); health maintenance organization	•AS-ME: ≥1   nurse visit for   individual   families •AAP •case   management •education on   trigger   reduction •review of   inhaler and   peak flow   meter   technique •linkage to PCP   or allergy   consult (if   indicated); nurse; $190 PMPM	↓ ED visits by   57% ↓ hospitalizations   by 75%	ROI: $6.49 per $1 Time to realize ROI: ~3 yearsd	RCT
Michigan: Self- Management Program for Adult Asthma (1986–1987)	Peer- reviewed journal:22 Other:21	Adults aged 18–70 years with asthma and ED visit (241 [control=122, intervention= 119]); NR	•AS-ME: 3   group sessions   (6–10 persons   each) •education on   asthma   triggers and   inhaler   technique •relaxation   exercises; nurse; $89/person	↓ ED visits by   59%	ROI: $22.50 per $1 Time to realize ROI: 1 year	RCT
New York: Open Airways (circa 1986)	Peer- reviewed journal:23–25 Other:21	Children aged 4–17 years with asthma and ≥1 wheezing episode in the past 12 months (310 [control=103, intervention= 207]); NR	•AS-ME: 6   group sessions   for families   (10–15   families each)   in clinic; health educator; $1,558 per family	Among all participants: No difference in   ED visits or   hospitalizations Among children with ≥1 hospitalization in the past year ↓ ED visits by   59% ↓ hospitalizations   by 58%	ROI (among all participants): $0.62 per $1 ROI (if ≥1 hospitalization in the past year): $11.22 per $1 Time to realize ROI: 2 yearsd	RCT
North Carolina: Asthma Self- Management Program (1996)	Peer- reviewed journal:26 Other: N/A	Persons aged ≥14 years with asthma (110); commercial insurance	•AS-ME: 8   group sessions •education on   communication   strategies with   clinicians,   inhaler use, and   trigger   reduction •supplies   (asthma   journal, peak   flow meter,   relaxation   tape); NR; ~$450 per participant	↓ ED visits ↓ urgent care     visits	ROI $2.54 per $1 Time to realize ROI: 3 yearsd	Pre– post
Ohio: Self- Management Program for Adult Asthma (circa 1990)	Peer- reviewed journal:27, 28 Other: N/A	Adults aged 27–70 years with asthma ≥6 months (47); NR	•AS-ME: 7   group   sessions •asthma diary •education on   peak flow   meter use; NR; $208 per participant	↓ hospitalizations	ROI: $2.28 per $1 Time to realize ROI: 2 yearsd	Pre– post
Multi-state: National Cooperative Inner-City Asthma Studye (circa 1997)	Peer- reviewed journal:29–31 Other:32	Low-income children aged 5–11 years with ≥2 asthma medications, ≥1 hospitalization or unscheduled visit, or uncontrolled symptoms (1,033 [control=518, intervention= 515]); NR	•AS-ME: 2   group sessions   for caregivers   and 2 group   sessions for   children •linkage to   community   resources •review of   inhaler   technique •supplies   (bedding   encasements) •physicians   received   spacer, peak   flow meter,   EPR-3, and   blank AAP for   each child; social worker ± exterminatorf; average $337 per child	↓ hospitalizations	ROI (all participants): <$1 per $1 ROI (if ≥1 hospitalization or ≥2 unscheduled visits in the past 2 months): >$1 per $1 Time to realize ROI: 2 years	RCT

AAP, asthma action plan; AS-ME, asthma self-management education; CHW, community health worker; ED, emergency department; MCO, managed care organization; PCP, primary care provider; PMPM, per member per month; N/A, not available; NR, not reported; RCT, randomized controlled trial.

^aExcludes programs that included home visits. Evidence supporting home visit programs is presented in Table III.

^bSample sizes reported herein are those used to determine economic outcomes.

^cQuantitative data are provided if these were available. These are not adjusted to today’s dollars; they are reported in each program at the time of report or publication.

^dActual time to realize ROI might be shorter because this estimate included pre-intervention data (typically 1 year of pre-intervention data) used to calculate ROI.

^eParticipating states/districts: IL, MD, MI, MO, NY, OH, and Washington DC.

^fHomes of children who were found to be cockroach allergic on allergy testing received professional application of insecticide over 2 visits.

All 4 U.S. Census regions were represented among the 9 programs with ROI data (Figure E1). Most programs (6/9) occurred in exclusively urban settings^{15–21, 23–25, 27–31}; 1 included both urban and suburban sites²², and information was not available for the remaining 2 programs.^{13, 14, 26}

Over half of programs with ROI data (5/9) only enrolled children^{15, 16, 18–20, 23–25, 29–31}, and 2 others included both children and adults.^{13, 14, 26} Only 2 were adult-specific.^{22, 27, 28} Beyond asthma, eligibility requirements for most programs (6/9) included some specification of asthma severity, control, or risk. Sample sizes used to determine ROI were available for 8/9 programs (median=220; range, 47–1,033).

Most programs (6/9) provided intensive outpatient AS-ME in ≥1 group session (maximum=8); 3 provided AS-ME to individuals or individual families (2 face-to-face^{15, 18–20}, 1 through regular phone calls^{13, 14}). Program personnel included nurses, respiratory therapists, social workers, and community health workers (CHWs). Also, programs varied widely in scope and type of additional interventions offered (e.g., case management, linkage to clinical or social services, supplies such as peak flow meters or bedding encasements).

The methodology used to evaluate program outcomes was primarily randomized controlled trial (RCT; 6/9); pre–post analysis was applied to 3 programs.^{13, 26–28} Length of participant follow-up (reported for 8/9 programs) ranged from 6 months–2 years. ROI calculations all incorporated ED visits and hospitalizations but varied substantially in other included considerations (e.g., discount rates and costs of medications, nebulizers, ambulances, or scheduled or unscheduled office visits). For all but one program^{27, 28}, reported ROIs excluded potential cost savings from reductions in work or school absenteeism.

Reductions in asthma-related ED visits or hospitalizations for program participants were reported for most (6/9) programs. In another program, decreased ED visits and hospitalizations occurred exclusively among program participants with ≥1 hospitalization in the past year.^23–25 No effect on asthma-related health care utilization was reported for only 1 program.¹⁵

Eight out of 9 programs were associated with a positive ROI (i.e., >$1 return per $1 invested) for all or some participants (Table II); among these, 2 programs achieved positive ROIs only among participants with higher health care utilization for asthma (e.g., ≥1 hospitalization or ≥2 unscheduled visits within a certain timeframe prior to program participation).^{23–25, 29–31} Estimated time to achieve ROI ranged from 1–3 years.

Table II.

Distribution of Return on Investment (ROI) for Intensive Outpatient Asthma Self-Management Education (AS-ME) and Asthma-Related Home Visit Programs in the United States

Return on Investment	Number of U.S. Programs
	AS-ME	Home Visit
Positive (>$1 per $1 invested)	6	14
Varied by populationa	2	1
Negative (<$1 per $1 invested)	1	2

ROI, return on investment

^aPositive ROI reported for some program participants (e.g., younger age or higher health care utilization prior to program entry) but not others.

Asthma-Related Home Visit Programs

We identified 17 U.S. programs that provided ≥1 asthma-related home visit and reported ROI (Table III).^{8, 21, 33–84} Approximately half (9/17) were identified in peer-reviewed literature.^{36, 46–48, 54, 60, 63, 64, 76, 77, 80, 81, 83, 84} An additional 25 U.S. programs providing ≥1 asthma-related home visit reported cost savings without ROI data (Table E3).

Table III.

U.S. Programs With Return On Investment Data For Asthma-Related Home Visits, By State

State: Program (Dates)	Reference	Participants (Na); Health Insurance Sector	Intervention(s); Personnel; Program Cost	Health Care Utilization Outcomeb	Economic Outcomeb	Study Design
California: Asthma Start (2001–present)	Peer- reviewed journal: N/A Other:21, 33–35	Children aged ≤18 years with asthma referred through multiple mechanisms (NR); Medicaid MCO	•2–3 home   visits •AS-ME •case   management •supplies   (bedding   encasements,   cleaning   supplies,   cockroach   traps, HEPA   vacuum) •linkage to   PCP; social worker; NR	↓ ED visits by   90% ↓ hospitalizations   by 90%	ROI: $5–7 per $1 Time to realize ROI: NR	Pre–post
Illinois: Sinai Pediatric Asthma Initiative-2 (2004–2005)	Peer- reviewed journal:36 Other: N/A	Children aged 2–16 years with severe, poorly controlled asthma (50); Medicaid	•3–4 home   visits •AAP (if   indicated) •AS-ME •education on   device or   medication   technique •linkage to   PCP; CHW; NR	↓ urgent health care utilization (ED visits, hospitalizations, or urgent clinic visits) by 75%	ROI: $5.58 per $1 Time to realize ROI: 2 yearsc	Pre–post
Indiana: Parkview ED Asthma Call Back Program (2009–present)	Peer- reviewed journal: N/A Other:37–41	Persons who visit ED for asthma (NR); NR	•≤3 home visits   (if indicated)   with supplies   (bedding   encasements,   cleaning   supplies,   HEPA   vacuum) •AS-ME •linkage to PCP   (if indicated) •medication   assistance   program; health department staff, nurse, respiratory specialist; NR	↓ ED visits	ROI: $20 per $1 in the first year, $23.75 per $1 in 2012 Time to realize ROI: 1 year	Comparison group, not RCT
Massachusetts: Cambridge Health Alliance (CHA) Partnership with Cambridge Public Health Department’s Healthy Homes Program (2002–present)	Peer- reviewed journal: N/A Other:21, 42–45	Children aged ≤12 years with asthma eligible for home visits, but all children with asthma eligible for other CHA services (NR); Medicaid MCO	•3+ home visits   (if indicated)   with supplies   (bedding   encasements,   cleaning   supplies, fire   extinguisher,   smoke   detector) •AS-ME •asthma registry •clinician   training •linkage to PCP   and school; health department staff, nurse; NR	↓ ED visits by   50% ↓ hospitalizations   by 45%	ROI: $4.29 per $1 Time to realize ROI: 7 yearsd	NR
Massachusetts: Community Asthma Initiative (2005–present)	Peer- reviewed journal:46–48 Other:8, 21, 49–53	Children with asthma (2–18 years) with prior ED visit or hospitalization (661 [control=559, intervention= 102]); Medicaid MCO, commercial insurance	•1+ home visits •AS-ME •case   management • linkage to   social services •supplies   (bedding   encasements,   HEPA vacuum,   IPM materials); CHW, nurse; $219 per child per month	↓ ED visits by   68% ↓ hospitalizations   by 85%	ROI: $1.33 per $1 Time to realize ROI: 4 yearsc	Comparison group, not RCT
Michigan: Asthma Network of West Michigan MATCH program (1994–present)	Peer- reviewed journal:54 Other:21, 55–59	Adults and children with moderate to severe asthma or uncontrolled asthma (NR); commercial insurance, Medicaid MCO	•3–6+ home   visits •AAP •AS-ME •case   management •linkage to PCP   and (if   indicated)   school,   daycare, work,   or social   services •psychosocial   interventions •spacer; AE-C, social worker; NR	↓ ED visits by   60% ↓ hospitalizations   by 64% ↓ hospital length-   of-stay by 46%	ROI: $2.10 per $1e Time to realize ROI: NR (but ED and hospital charges ↓ in the first year of the pilot)	Pre–post
Michigan: Healthy Homes University in Lansing (2005–present)	Peer- reviewed journal:60 Other:55, 61	Children aged ≤18 years with asthma from low-moderate income households (243); commercial insurance, Medicaid	•4 home visits •AS-ME •supplies   bedding   encasements,   cleaning   supplies,   HEPA vacuum,   IPM materials); variedf; $1,055 per household for administrative operating costs + $230 per home visit for staff and travel + average of $387 for supplies given to familiesg	↓ ED visits by   53% ↓ hospitalizations   by 68% ↓ unscheduled   visits by 48%	ROI: >$1 per $1e Time to realize ROI: 3 years	Pre–post
Minnesota: Environmental Improvements for Children’s Asthma (2005– 2009)	Peer- reviewed journal: N/A Other:62	Low-income children with: (1) moderate or severe persistent asthma or (2) milder asthma but ED visit, hospitalization, or school absence (255); NR	•2 home visits •supplies   (allergen-   reducing   products); AE-C; $621 per home ($321 for staff + $301 for supplies)	Parent report from entire sample ↓ ED visits ↓ hospitalizations Subanalysis of health plan data (n=48) ↓ ED visits by   44% ↓ hospitalizations   by 68%	ROI (total health care): $2.19 per $1 ROI (asthma- related health care): $1.76 per $1 Time to realize ROI: 4 years	Pre–post
Minnesota: Reducing Environmental Triggers of Asthma (2011–2013)	Peer- reviewed journal:63, 64 Other:8, 56, 65, 66	Children with asthma living in low-income housing (118); NR	•3–4 home   visits •AS-ME •education on   reducing   environmental   asthma triggers •supplies   (bedding   encasements,   cleaning   supplies,   HEPA filter,   vacuum); nurse; average of $424 per family (range, $286–624)	↓ ED visits ↓ hospitalizations ↓ urgent care   visits	ROI: $1.61 per $1 Time to realize ROI: 1 year	Pre–post
New York: The Bronx Improving Asthma Care for Children Project (2002–2005)	Peer- reviewed journal: N/A Other:67–69	Children with: (1) moderate or severe asthma or (2) prior ED visit or hospitalization (NR); Medicaid MCO	•1 home visit •AS-ME •case   management •clinician   training; case manager, respiratory therapist, others; $78 PMPY among pediatric asthma plan membersh	↓ ED visits by   75% ↓ hospitalizations   by 66%	ROI: $10 per $1 among pediatric asthma members of the health plan; $3 per $1 across the entire health plan Time to realize ROI: 3 years	Comparison group, not RCT
New York: Monroe Plan for Medical Care’s Improving Asthma Care for Children Initiative (2001–2004)	Peer- reviewed journal: N/A Other:21, 69–72	Children with asthma (NR); Medicaid MCO, S-CHIP	•1 home visit •AAP •allergy testing •AS-ME •case   management •linkage to   social services •supplies   bedding   encasements,   HEPA filter) •spirometry; outreach worker; $30 PMPM	↓ ED visits by   78% ↓ hospitalizations   by 60%	ROI: $1.48 per $1 Time to realize ROI: 4 yearsc	Pre–post
Ohio: Home Health Asthma Pathway within the Cincinnati Children’s Medical Center Asthma Improvement Collaborative (2008–2011)	Peer- reviewed journal: N/A Other:73–75	Children with asthma and ED visit or hospitalization meeting additional criteriai(NR); Medicaid	•3–5 home   visits •AS-ME •case   management •linkage to PCP   and MCO •medication   review; nurse; $1.2 million total over 3 years	↓ acute utilization   (ED visits and   hospitalizations),   but this did not   differ from   comparison   group	ROI: <$1 per $1 Time to realize ROI: 3 years	Comparison group, not RCT
Pennsylvania: National Jewish Medical and Research Center Disease Management Program for Asthma (western Pennsylvania) (circa 1999)	Peer- reviewed journal:85 Other:21	Adults and children aged >12 years with moderate or severe asthma (317); Medicaid MCO	•2 home visits •AS-ME •case   management •physician   education and   helpline; home health care agency, nurse; $303 per patient per 6 months	↓ ED visits by   76% ↓ hospital days by   37% ↓ ICU admissions   by 66%	ROI: $4.64 per $1 Time to realize ROI: 1.5 yearsc	Pre–post
Rhode Island: Parents of Asthmatics Quit Smoking (2001–2004)	Peer- reviewed journal:76, 77 Other: N/A	Children ≤17 years with asthma and with caregivers who smoked (224); Medicaid MCO	•3 home visits •AS-ME •linkage to PCP •tobacco   cessation   counseling for   caregiver; nurse; $34,481 total ($17,240 for children <6 years; $15,851 for children with moderate or persistent asthma)	↓ hospitalizations ↓ outpatient visits	ROI <$1 per $1 for entire program and children aged ≥6 years (n=112) ROI >$1 per $1 for children <6 years (n=112) Time to realize ROI: 2 yearsc	Pre–post
Virginia: Optima Health Asthma Management Services (1994–present)	Peer- reviewed journal: N/A Other:21, 78, 79	Adults and children with asthma and ED visit, hospitalization, or physician referral (NR); commercial insurance, Medicaid	•home visits   (average=4) •AAP •AS-ME •case   management; case manager, nurse, respiratory therapist; $425 PMPY	Medicaid: ↓ ED visits by   33% ↓ hospitalizations   by 32% Commercial insurance: ↓ ED visits by   18% ↓ hospitalizations   by 54%	ROI (combined Medicaid & commercial populations): $4.40 per $1 Time to realize ROI: 5 years	Pre–post
Washington: Seattle-King County Healthy Homes (1999–present)	Peer- reviewed journal:80, 81 Other:55, 82	Children with uncontrolled asthma (373 [control=191, intervention= 182]); Medicaid	• 2–4 home   visits • AS-ME • case   management • linkage to   social services • supplies   (bedding   encasements,   cleaning   supplies, IPM   materials [if   indicated],   vacuum); CHW; $205 per home visit	↓ urgent health care utilization (ED visits, hospitalizations, or urgent clinic visits)	ROI: $1.90 per $1 Time to realize ROI: 2 yearsc	RCT
Multi-state: Inner City Asthma Studyj (1998–2000)	Peer- reviewed journal:83, 84 Other: N/A	Low-income children aged 5–11 years with asthma meeting multiple criteriak (800 [control=392, intervention= 408]); commercial insurance, Medicaid, Medicaid MCO, uninsured	•home visits   (median=5) •supplies   (bedding   encasements,   cleaning   supplies,   HEPA vacuum,   and [if   indicated]   HEPA air   cleaner or vent   filter) •pest control (if   indicated); CHW with environmental counselor training; $1,472 per family	No change in ED   visits or   hospitalizations ↓ unscheduled   clinic visits by   19%	ROI: <$1 per $1 Time to realize ROI: 2 years	RCT

AAP, asthma action plan; AE-C, certified asthma educator; AS-ME, asthma self-management education; CHW, community health worker; ED, emergency department; ICU, intensive care unit; IPM, integrated pest management; MCO, managed care organization; N/A, not available; NR, not reported; PCP, primary care provider; PMPM, per member per month; PMPY, per member per year; RCT, randomized controlled trial; ROI, return on investment; S-CHIP, State Children's Health Insurance Program.

^aSample sizes reported herein are those used to determine economic outcomes.

^bQuantitative data are provided if these were available. These are not adjusted to today’s dollars; they are reported in each program at the time of report or publication.

^cActual time to realize ROI might be shorter because this estimate included pre-intervention data (typically 1 year of pre-intervention data) used to calculate ROI.

^dROI calculations for shorter time intervals were not available, so the minimum time required to realize a positive ROI is unclear.

^eROI data obtained from non-peer-reviewed reference; ROI not reported in peer-reviewed source.

^fStaff had degrees in biology, medical technology, or environmental science, with prior experience in clinical research, low-income housing, and environmental contaminant investigation.

^gAlso, for the 12% of households required custom home remediation, the average cost of these services was $2,647 per household.

^h$3.37 PMPY health plan-wide; total program cost ~$500,000 over 3 years.

ⁱChildren were eligible for home visits through the Home Health Asthma Pathway component if they met additional criteria such as medication nonadherence, unresolved home environmental triggers, or need for more AS-ME; children not meeting these criteria could receive other services (e.g., case management) from the overall program (i.e., the Cincinnati Children’s Medical Center Asthma Improvement Collaborative).

^jParticipating states: AZ, IL, MA, NY, TX, WA.

^kAdditional inclusion criteria were: (1) allergy to ≥1 indoor allergen and (2) ≥1 hospitalization or ≥2 urgent visits for asthma in the past 6 months. Children had to meet all inclusion criteria to be eligible to participate.

All 4 U.S. Census regions were represented among the 17 programs with ROI data, but programs were predominantly located in the Midwest (7/17) and Northeast (6/17). Most programs (12/17) operated in urban settings^{33–36, 42–44, 46–49, 60, 62, 65–67, 70, 71, 73–75, 80, 81, 83, 84}, and information was not available for the remaining 5 programs.^{37–41, 54, 59, 76–79, 85} Program descriptions indicated health insurance plans operated or served as partners in over one-third (6/17) of programs.^{33, 43, 54, 55, 59, 67, 70, 71, 78, 79}

All 17 programs enrolled children (13 exclusively, and 4 included both children and adults^{37–41, 54, 55, 57–59, 78, 79, 85}); none were adult-specific. Eligibility requirements varied across programs. Sample sizes used to determine ROI were available for 9 out of 17 programs (primarily in peer-reviewed literature). Median sample size for calculating ROI was 255 (range, 50–800).

Most (13/17) programs provided ≥1 home visit to all program participants. In 4 programs, home visits were a program component offered to selected individuals based on varied or unspecified criteria.^{37–44, 55, 73–75, 78, 79} Among 15 of the 17 programs, total number of home visits per individual ranged from 1–8; another program averaged 4 home visits per participant^{78, 79} and one provided a median of 5 home visits per person.^{83, 84} The time frame over which home visits occurred (when reported) varied from 2 weeks to 1 year.

Program personnel included nurses, respiratory therapists, certified asthma educators, social workers, environmental health specialists, health department or home health care staff, and CHWs (4/17 programs). Descriptions for 10/17 programs indicated participants received supplies, typically bedding encasements or cleaning supplies. Only 1 program gave spacers to participants.^{54, 59} Linkages to primary care providers were reported in 8 out of 17 programs; other linkages included school, child care, work, pest management, and other social services.

Pre–post evaluation was the most common method to measure program outcomes (9/17 programs). RCTs were conducted for 2 programs^{80, 81, 83, 84}, and a comparison group (non-randomized) was used to assess 4 additional programs.^{46–49, 75} Evaluation methodology was not available for 2 programs.^{43, 44, 54, 59} Length of participant follow-up (reported for 10/17 programs) ranged from 6 months–3 years.

Program descriptions varied widely in whether methodology to determine ROI was mentioned (typically but not universally present in peer-reviewed literature). When available, ROI calculations differed in which data were incorporated (e.g., discount rates, medications, office visits, or obtaining hospitalization costs from participants’ insurance claims data versus estimating costs from hospital surveys). Program costs were reported for 12 out of 17 programs. Notably, ROI determination methods were largely uniform in excluding cost savings related to reduced work/school absenteeism, with the exception of 1 program.⁸⁵

Decreases in asthma-related ED visits or hospitalizations for program participants were reported for most (15/17) programs. A few program descriptions also included outcomes such as shorter hospitalization length-of-stay, fewer intensive care unit admissions, and reduced urgent care or unscheduled office visits.^{36, 54, 59, 60, 66, 80, 84, 85}

Most programs (14/17) were associated with a positive ROI. Two programs had negative ROIs^{75, 84}, and 1 program achieved a positive ROI only among selected participants (i.e., aged <6 years).⁷⁶ Median estimated time to achieve ROI was 3 years (range, 1–11 years).

Summary

In our literature review of economic outcomes for intensive outpatient AS-ME and home-based intervention programs for asthma in the United States, we found ROI data for 9 programs providing intensive outpatient AS-ME and 17 programs offering asthma-related home visits. Most programs were associated with a positive ROI; a few programs observed positive ROIs only among selected populations (e.g., higher urgent health care utilization for asthma or younger children). Methodology to calculate ROIs (when reported) varied across programs.

This review builds on prior work^{63, 86} by updating, comprehensively synthesizing, and examining current evidence regarding economic sustainability of intensive outpatient AS-ME and home-based intervention programs for asthma in the United States. These findings represent timely evidence for clinicians, health care administrators, public health officials, policy makers, investigators and others to consider expanding health care-public health collaboration efforts to improve asthma control.^{7, 8, 87} This review’s categorization of programs by state can facilitate local activities while providing a broader understanding of the current state of evidence. Additionally, provision of subtopic-specific materials in the Online Repository (i.e., Tables E4 and E5 on evidence for CHWs, Tables E6 and E7 on evidence for adult-focused programs, Tables E8 and E9 on evidence for programs involving health insurance plans) can inform ongoing discussions about how and when to implement programs with certain personnel or populations.

This review had several limitations. Publication bias might have caused positive findings to be overrepresented in the literature. For example, publication bias could be a reason why fewer ROIs were found for more recent (e.g., 2000–present) intensive outpatient AS-ME programs compared to older programs; other potential explanations include funding availability or views on the value or achievability of ROIs for such programs. Another limitation relevant to both intensive outpatient AS-ME and home-based asthma interventions was that studies without observed cost savings might have omitted cost data in their reports. Among studies with cost savings data, price years of dollar values were inconsistently reported, so we could not convert dollar values to a single price year for direct comparison. Similarly, heterogeneity in ROI calculation methodology could limit comparability of ROI across programs (e.g., effects of age, season, or time itself might not be fully addressed in a pre–post design compared to RCT). This review focused on cost-benefit analyses involving direct medical costs (e.g., ED visits, hospitalizations); program cost-effectiveness and effects on indirect costs (i.e., work or school absenteeism) were beyond the scope of this review. Lastly, these findings might not be generalizable to programs outside the United States or U.S. programs conducted in inpatient^{88, 89}, military^{90, 91}, school⁹², or residential camp settings.⁹³

Future Directions

This review highlights opportunities to improve understanding of economically sustainable programs offering intensive outpatient AS-ME and multifaceted home-based asthma interventions. No economic outcome data were available for programs in rural settings. Compared to children, evidence for adult-specific programs offering intensive outpatient AS-ME and home-based asthma interventions was relatively limited. Similarly, programs involving CHWs were less abundant than programs involving health professionals, despite increasing interest in this topic. The literature could be more conclusive if methodology to determine ROI was more consistent. For home-based intervention programs, a remaining question is the relative impact of AS-ME, environmental education, and supplies or services for environmental trigger reduction on health and economic outcomes (either immediately following or several years after program participation).

Conclusions

In conclusion, this review examines current economic evidence regarding intensive outpatient AS-ME and home-based intervention programs for asthma in the United States. Interpretation of existing data is constrained by heterogeneous ROI calculations and other limitations. Nevertheless, the literature suggests promise for sustainable opportunities to strengthen health care-public health collaboration for improved asthma control, especially among populations at higher risk for adverse events. More definitive knowledge about how to maximize program benefit and sustainability could be gained through more controlled studies of specific populations and increased uniformity in economic assessments.

Abbreviations used

AS-ME

asthma self-management education

CHW

community health worker

ED

emergency department

EPR-3

2007 National Asthma Education and Prevention Program Guidelines for the Diagnosis and Management of Asthma

RCT

randomized controlled trial

ROI

return on investment