Children and Adolescents With Attention Deficit-Hyperactivity Disorder: 1. Prevalence and Cost of Care Larry Burd, PhD; Marilyn G. Klug, PhD; Matthew J

Children and Adolescents With Attention Deficit-Hyperactivity

Disorder: 1. Prevalence and Cost of Care

Larry Burd, PhD; Marilyn G. Klug, Larry Burd, PhD; Marilyn G. Klug, PhD; Matthew J. Coumbe, PhD; PhD; Matthew J. Coumbe, PhD;

Jacob Kerbeshian, MDJacob Kerbeshian, MD

Abstract The objective of this study was to use population-based data to estimate the The objective of this study was to use population-based data to estimate the

prevalence and cost of treatment for attention-deficit hyperactivity disorder prevalence and cost of treatment for attention-deficit hyperactivity disorder (ADHD). The case population was 7745, and the mean prevalence rate was (ADHD). The case population was 7745, and the mean prevalence rate was 3.9%, with a peak prevalence at 10 years of age. For children with ADHD, the 3.9%, with a peak prevalence at 10 years of age. For children with ADHD, the annual cost of care was $649 compared with that of controls at $495. Cost of annual cost of care was $649 compared with that of controls at $495. Cost of care attributable to ADHD was $694 - $495 = $154 (31%). Utilization by care attributable to ADHD was $694 - $495 = $154 (31%). Utilization by children with ADHD with publicly funded payers was increased 25 to 175% children with ADHD with publicly funded payers was increased 25 to 175% over that of children with privately funded coverage. In North Dakota, the over that of children with privately funded coverage. In North Dakota, the annual cost of care for children with ADHD was $5.1 million, 5.6% of all annual cost of care for children with ADHD was $5.1 million, 5.6% of all health care costs for children. The annual attributable cost of care was $1.79 health care costs for children. The annual attributable cost of care was $1.79 million. Thus, 1.9% of total health expenditures for children was attributable million. Thus, 1.9% of total health expenditures for children was attributable to ADHD. In the United States, the cost of care attributable to children with to ADHD. In the United States, the cost of care attributable to children with ADHD would be $2.15 billion annually. (ADHD would be $2.15 billion annually. (J Child NeurolJ Child Neurol 2003;18:555-561). 2003;18:555-561).

Current Study• In this study, we used the health claims data from the North

Dakota Department of Health, to determine:

1) the administrative prevalence of ADHD in the state of North Dakota

2) differences in cost of care for children and adolescents with ADHD compared with the subjects who do not have ADHD, and

3) differences in prevalence and cost by payer type (private coverage or publicly funded health insurance).

Inclusion Criteria: Cases Patients were included in the study as cases with ADHD if at any Patients were included in the study as cases with ADHD if at any

timed during either year they had an timed during either year they had an Internal Classification of Internal Classification of DiseasesDiseases, 9, 9thth edition (ICD-9), code of 314.00 or (attention-deficit edition (ICD-9), code of 314.00 or (attention-deficit disorder not otherwise specified), 314.00 (inattention type), 314.01 disorder not otherwise specified), 314.00 (inattention type), 314.01 (with hyperactivity/impulsiveness), or 314.8 (with other specific (with hyperactivity/impulsiveness), or 314.8 (with other specific manifestations). The code 314.9 (attention-deficit hyperactivity manifestations). The code 314.9 (attention-deficit hyperactivity disorder not otherwise specified) was also included to capture cases disorder not otherwise specified) was also included to capture cases from the from the Diagnostic and Statistical Manual of Mental Disorders-IV Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV(DSM-IV). This is the coding strategy used to specify children with a ). This is the coding strategy used to specify children with a diagnosis of ADHD in the DSM-IV. If the codes (314.xx) were diagnosis of ADHD in the DSM-IV. If the codes (314.xx) were identified in any order in the diagnostic formulation in the database at identified in any order in the diagnostic formulation in the database at any time during the year, the subject was classified as a case.any time during the year, the subject was classified as a case.

Inclusion Criteria:Controls

The controls were all remaining subjects 0 The controls were all remaining subjects 0 to 21 years of age in the database who did to 21 years of age in the database who did not have an ICD-9 code of 314.00, 314.01, not have an ICD-9 code of 314.00, 314.01, or 314.8 or the DSM-IV code 314.9 in their or 314.8 or the DSM-IV code 314.9 in their diagnostic formulation.diagnostic formulation.

In this sample, we had 24.5 controls for In this sample, we had 24.5 controls for each case.each case.

Limitations

The data are from North Dakota, a small The data are from North Dakota, a small rural state with a total population in 1997 of rural state with a total population in 1997 of 650,000. The data for this study are health 650,000. The data for this study are health care claims data and might reflect coding care claims data and might reflect coding error or bias.error or bias.

Two significant populations not represented Two significant populations not represented in these data were uninsured children and in these data were uninsured children and the Native American population.the Native American population.

Calculation of Costs

Two types of costs were defined: base cost and Two types of costs were defined: base cost and attributable cost. The base cost was the cost a attributable cost. The base cost was the cost a control child generated on average during the year. control child generated on average during the year. Attributable costs were costs added to the base Attributable costs were costs added to the base cost for a specific illness. The cost and group cost for a specific illness. The cost and group (ADHD or control) interactions were examined by (ADHD or control) interactions were examined by a linear equation with two cost elements. This a linear equation with two cost elements. This database does not include the cost of medication.database does not include the cost of medication.

0

2

4

6

8

10

12

Inf 2 4 6 8 10 12 14 16 18 20

Total

Male

Female

Graph of prevalence by age and gender

(male, female, and total group).

Graph of prevalence rate in percentage by age of cohort and payer type (public, private, or total group).

Comparison of Mean (1996-1997) Costs Between Children With ADHD and Without (Controls) by

Payment MethodHCFAHCFA

AnnualAnnual MeanMean

MeanMean Cost perCost per

NN CostCost VisitVisit

TotalTotal 98,99198,991

ADHDADHD 38723872 $648.55*$648.55* $158.59*$158.59*

ControlsControls 95,11995,119 $494.53$494.53 $112.10$112.10

PrivatePrivate 80,81980,819

ADHDADHD 28012801 $568.79*$568.79* $155.79*$155.79*


PublicPublic 18,17218,172

ADHDADHD 10711071 $856.03*$856.03* $166.37*$166.37*

ControlsControls 17,10117,101 $480.07$480.07 $109.84$109.84*Mean costs of children with ADHD significantly higher than those of controls (P<.01)

ADHD = attention-deficit hyperactivity disorder; HFCA = Health Care Financing Administration

Comparison of Mean (1996-1997) Costs Between Children With ADHD and Without (Controls) by

GenderHFCAHFCA

AnnualAnnual MeanMean

MeanMean Cost perCost per

NN CostCost VisitVisit

MaleMale 48,76048,760

ADHDADHD 29082908 $612.36*$612.36* $156.91$156.91


FemaleFemale 50,23150,231

ADHDADHD 964964 $757.92*$757.92* $163.66*$163.66*


*Mean costs of children with ADHD significantly higher than those of controls (P<.01)


Comparison of Mean (1996-1997) Costs Between Children With ADHD and Without (Controls) by Payment Method

InpatientInpatient OutpatientOutpatient

AnnualAnnual MeanMean AnnualAnnual MeanMean

MeanMean Cost perCost per MeanMean Cost perCost per

CostCost VisitVisit NN CostCost VisitVisit

TotalTotal 25,55325,553

ADHDADHD $8861.48*$8861.48* $5702.43*$5702.43* 613613 $1597.31$1597.31 $577.98*$577.98*

ControlsControls $5528.89$5528.89 $3942.54$3942.54 24,92024,920 $644.29$644.29 $288.24$288.24

PrivatePrivate 11,87211,872

ADHDADHD $9592.39$9592.39 $5881.46$5881.46 142142 $1815.32*$1815.32* $879.29*$879.29*


PublicPublic 13,66113,661

ADHDADHD $8717.90$8717.90 $5681.21$5681.21 471471 $1527.57*$1527.57* $497.48*$497.48*


*Mean cost of children with ADHD significantly higher than those of controls (P<.01)


Comparison of Mean (1996-1997) Costs Between Children With ADHD and Without (Controls) by Gender

InpatientInpatient OutpatienOutpatientt

AnnualAnnual MeanMean Annual Annual MeanMean

MeanMean Cost perCost per MeanMean Cost perCost per

CostCost VisitVisit NN CostCost VisitVisit

MaleMale 12,61712,617

ADHDADHD $9102.72$9102.72 $5947.87$5947.87 468468 $1470.68*$1470.68* $559.64$559.64

ControlsControls

$6811.52$6811.52 $4467.20$4467.20 12,14912,149 $642.20$642.20 $296.08$296.08

FemaleFemale 12,91612,916

ADHDADHD $8156.47*$8156.47* $4996.10*$4996.10* 145145 $2014.96*$2014.96* $639.31$639.31

ControlsControls

$4664.75$4664.75 $3886.29$3886.29 12,77112,771 $646.30$646.30 $280.79$280.79

*Mean cost of children with ADHD significantly higher than those of controls (P<.01)


Results

The prevalence of ADHD increases slowly from The prevalence of ADHD increases slowly from birth until 2 years of age, when the prevalence is birth until 2 years of age, when the prevalence is 0.3%. From 3 through 10 years of age, the 0.3%. From 3 through 10 years of age, the prevalence has a mean increase of 1.1% per year. prevalence has a mean increase of 1.1% per year. Prevalence peaks at 10.3% at 10 years of age and Prevalence peaks at 10.3% at 10 years of age and then decreases at a mean rate of about 1.0% per then decreases at a mean rate of about 1.0% per year until 18 years of age. After 18 years of age, year until 18 years of age. After 18 years of age, ADHD is diagnosed in 2% of the population.ADHD is diagnosed in 2% of the population.

Mean Cost Comparisons

The mean annual cost of care for children The mean annual cost of care for children with ADHD in the Health Care Financing with ADHD in the Health Care Financing Administration data was $649 per case or Administration data was $649 per case or 31% more than controls. The annual cost of 31% more than controls. The annual cost of attributable to ADHD was $154 ($649-attributable to ADHD was $154 ($649-$495) per case.$495) per case.

Proportion of Mean (1996-1997) Annual Number of Visits Between Children With ADHD and Without

(Controls) by Payment Type

HCFAHCFA

NumberNumber

NN %% Of VisitsOf Visits %%

TotalTotal 98,99198,991 337,141337,141

ADHDADHD 38723872 3.93.9 13,77913,779 4.1*4.1*

ControlsControls 95,11995,119 96.196.1 323,362323,362 95.995.9

PrivatePrivate 80,81980,819 274,389274,389

ADHDADHD 28012801 3.53.5 87408740 3.23.2


PublicPublic 18,17218,172 62,75262,752

ADHDADHD 10711071 5.95.9 50395039 8.0*8.0*


*Significant increase in proportion of number of visits for children with ADHD compared with proportion of children with ADHD in the sample (P<.01)

ADHD = attention-deficit hyperactivity disorder; HCFA = Health Care Financing Administration


(Controls) by Gender

HFCAHFCA

NumberNumber


MaleMale 48,76048,760 159,364159,364

ADHDADHD 29082908 6.06.0 97859785 6.06.0


FemaleFemale 50,23150,231 177,777177,777

ADHDADHD 964964 1.91.9 39943994 1.91.9






InpatientInpatient

NumberNumber


TotalTotal 46144614 60536053

ADHDADHD 183183 4.04.0 356356 5.9*5.9*

ControlsControls 44314431 96.096.0 56975697 94.194.1

PrivatePrivate 20122012 26742674

ADHDADHD 4040 2.02.0 6363 2.42.4


PublicPublic 26022602 33793379

ADHDADHD 143143 5.55.5 293293 8.7*8.7*




Proportion of Mean (1996-1997) Annual Number of Visits Between Children With ADHD and Without (Controls) by Gender

InpatientInpatient

NumberNumber


MaleMale 19591959 26822682

ADHDADHD 134134 6.86.8 263263 9.8*9.8*


FemaleFemale 26552655 33713371

ADHDADHD 4949 1.81.8 9393 2.82.8






OutpatientOutpatient

NumberNumber


TotalTotal 25,53325,533 67,08867,088

ADHDADHD 613613 2.42.4 28892889 4.3*4.3*


PrivatePrivate 11,87211,872 20,37020,370

ADHDADHD 142142 1.21.2 291291 1.41.4


PublicPublic 13,66113,661 46,71846,718

ADHDADHD 471471 3.43.4 25982598 5.6*5.6*

ControlsControls 13,19013,190 96.696.6 44,12044,120 94.494.4*Significant increase in proportion of number of visits for children with ADHD compared with proportion of children with ADHD in the sample (P<.01)



(Controls) by Gender


NumberNumber


MaleMale 12,61712,617 31,81131,811

ADHDADHD 468468 3.73.7 20842084 6.6*6.6*


FemaleFemale 12,91612,916 35,27735,277

ADHDADHD 145145 1.11.1 805805 2.3*2.3*




Inpatient Data

For inpatient data, the mean annual cost of For inpatient data, the mean annual cost of care for children with ADHD was $8861 or care for children with ADHD was $8861 or 60% more than controls, with an 60% more than controls, with an attributable cost of $3332 ($8861-$5529).attributable cost of $3332 ($8861-$5529).

Outpatient Data

For outpatient data, the mean annual cost of For outpatient data, the mean annual cost of care for children with ADHD was $1597. care for children with ADHD was $1597. This produced an attributable mean annual This produced an attributable mean annual cost of care for ADHD of $953 ($1592-cost of care for ADHD of $953 ($1592-$644), which was 148% greater than the $644), which was 148% greater than the cost for controls.cost for controls.

Public Payer Type

Annual mean costs for children with ADHD Annual mean costs for children with ADHD with public payers in the Health Care with public payers in the Health Care Financing Administration data set were Financing Administration data set were 78% higher than controls and 59% and 78% higher than controls and 59% and 176% higher than controls in the inpatients 176% higher than controls in the inpatients and outpatient data sets, respectively.and outpatient data sets, respectively.

Private Payer Type

Annual mean costs for children with ADHD Annual mean costs for children with ADHD in the inpatients data set were 10% higher in the inpatients data set were 10% higher for those with private payers and 19% for those with private payers and 19% higher in the outpatients data set. In the higher in the outpatients data set. In the Health Care Financing Administration data Health Care Financing Administration data sat, children with ADHD with public payers sat, children with ADHD with public payers had higher annual mean costs and mean had higher annual mean costs and mean costs per visit.costs per visit.

Comparison of Mean (1996-1997) Total Annual Costs Between Children With ADHD and Without

(Controls) by Payment Method, Gender, and Age Groups

HCFAHCFA

NN %% CostCost %%

TotalTotal 98,99198,991 $48,359,948$48,359,948

ADHDADHD 38723872 3.93.9 $2,546,024$2,546,024 5.3*5.3*

ControlsControls 95,11995,119 96.196.1 $45,813,924$45,813,924 94.794.7

PrivatePrivate 80,81980,819 $39,072,153$39,072,153

ADHDADHD 28012801 3.53.5 $1,609,533$1,609,533 4.1*4.1*


PublicPublic 18,17218,172 $9,287,796$9,287,796

ADHDADHD 10711071 5.95.9 $936,492$936,492 10.1*10.1*


*Significant increase in proportion of total cost for children with ADHD compared with proportion of children with ADHD in the sample (P<.01)




HCFAHCFA

NN %% CostCost %%

MaleMale 48,76048,760 $23,700,450$23,700,450

ADHDADHD 29082908 6.06.0 $1,803,345$1,803,345 7.6*7.6*


FemaleFemale 50,23150,231 $24,659,498$24,659,498

ADHDADHD 964964 1.91.9 $742,679$742,679 3.0*3.0*






InpatientInpatient

NN %% CostCost %%

TotalTotal 46144614 $25,912,447$25,912,447

ADHDADHD 183183 4.04.0 $1,628,127$1,628,127 6.3*6.3*

ControlsControls 44314431 96.096.0 $24,284,320$24,284,320 93.793.7

PrivatePrivate 20122012 $11,203,147$11,203,147

ADHDADHD 4040 2.02.0 $367,648$367,648 3.3*3.3*


PublicPublic 26022602 $14,709,301$14,709,301

ADHDADHD 143143 5.55.5 $1,260,479$1,260,479 8.6*8.6*



ADHD = attention-deficit hyperactivity disorder

Comparison of Mean (1996-1997) Total Annual Costs Between Children With ADHD and Without (Controls) by Payment

Method, Gender, and Age Groups

InpatientInpatient

NN %% CostCost %%

MaleMale 19591959 $13,337,729$13,337,729

ADHDADHD 134134 6.86.8 $1,233,750$1,233,750 9.2*9.2*


FemaleFemale 26552655 $12,534,718$12,534,718

ADHDADHD 4949 1.81.8 $394,377$394,377 3.13.1







NN %% CostCost %%

TotalTotal 25,53325,533 $17,050,071$17,050,071

ADHDADHD 613613 2.42.4 $991,152$991,152 5.8*5.8*


PrivatePrivate 11,87211,872 $8,941,555$8,941,555

ADHDADHD 142142 1.21.2 $256,992$256,992 2.9*2.9*


PublicPublic 13,66113,661 $8,108,516$8,108,516

ADHDADHD 471471 3.43.4 $734,160$734,160 9.1*9.1*





(Controls) by Payment Method, Gender, and Age GroupsOutpatientOutpatient

NN %% CostCost %%

MaleMale 12,61712,617 $8,493,406$8,493,406

ADHDADHD 468468 3.73.7 $699,253$699,253 8.2*8.2*


FemaleFemale 12,91612,916 $8,556,554$8,556,554

ADHDADHD 145145 1.11.1 $291,898$291,898 3.4*3.4*




Comparisons of Number of Visits

The proportion of the number of visits of The proportion of the number of visits of children with ADHD to the total number of children with ADHD to the total number of visits in the Health Care Financing visits in the Health Care Financing Administration data set is 4.1%, 5.9% in the Administration data set is 4.1%, 5.9% in the inpatients data, and 4.3% in the outpatient inpatients data, and 4.3% in the outpatient data. These proportions are significantly data. These proportions are significantly greater (P<.01) than the proportion of greater (P<.01) than the proportion of children with ADHD in the corresponding children with ADHD in the corresponding data set.data set.

Comparisons of Total Cost

Table 3 shows that children with ADHD Table 3 shows that children with ADHD accumulated costs totaling $2,546,024 + accumulated costs totaling $2,546,024 + $1,618,127 + $991,152 = $5,155,303 per $1,618,127 + $991,152 = $5,155,303 per year on average during 1996 and 1997. year on average during 1996 and 1997. Children with ADHD used 5.6% of the Children with ADHD used 5.6% of the $91,322,466 total cost incurred by all $91,322,466 total cost incurred by all children in the three data sets.children in the three data sets.

Mean Attributable Cost of Health Care to Children With ADHD in North Dakota for

1996 and 1997 by HCFA Dataset

HFCAHFCA

PayerPayer

GroupGroup NN

MeanMean

Attributable Attributable

CostCost

TotalTotal

AttributableAttributable

CostCost

PrivatePrivate 28012801 $66$66 $184,866$184,866

PublicPublic 10711071 $376$376 $402,969$402,969

TotalTotal 38723872 $154$154 $591,668$591,668


Mean Attributable Cost of Health Care to Children With ADHD in North Dakota for 1996

and 1997 by Inpatient Dataset

InpatientInpatient

PayerPayer

GroupGroup nn

Mean Mean


CostCost

TotalTotal


CostCost

PrivatePrivate 4040 $3888$3888 $155,420$155,420

PublicPublic 143143 $3249$3249 $464,607$464,607

TotalTotal 183183 $3332$3332 $609,756$609,756


Mean Attributable Cost of Health Care to Children With ADHD in North Dakota for 1996

and 1997 by Outpatient Dataset


PayerPayer

GroupGroup NN

MeanMean


CostCost

Total Total


CostCost

PrivatePrivate 142142 $1049$1049 $148,958$148,958

PublicPublic 471471 $974$974 $458,754$458,754

TotalTotal 613613 $1049$1049 $584,189$584,189


Policy Implications

The total mean annual cost of care The total mean annual cost of care attributable to ADHD in North Dakota in attributable to ADHD in North Dakota in 1996 and 1997 was $1.79 million.1996 and 1997 was $1.79 million.

Policy Implications

For children with private coverage, the For children with private coverage, the attributable cost of $489,344 was 27.4% of attributable cost of $489,344 was 27.4% of all health care costs attributable to AHDS.all health care costs attributable to AHDS.

Policy Implications

The attributable cost of care for children The attributable cost of care for children with publicly funded care was $1,326,057 with publicly funded care was $1,326,057 or 74.3% of the total attributable costs of or 74.3% of the total attributable costs of care attributable to ADHD in North Dakota care attributable to ADHD in North Dakota (see Table 4). This was 1.5% of the total (see Table 4). This was 1.5% of the total cost of care for all of the children in the cost of care for all of the children in the dataset.dataset.

Policy Implications

Utilization measured by the number of Utilization measured by the number of visits per year for children in the Health visits per year for children in the Health Care Financing Administration data set was Care Financing Administration data set was 3.1 visits per year for private payers versus 3.1 visits per year for private payers versus 4.7 for public payers.4.7 for public payers.

Policy Implications

In 1997, the United States population of In 1997, the United States population of 85,091,200 children with a 3.9% prevalence rate 85,091,200 children with a 3.9% prevalence rate for ADHD would produce a total population of for ADHD would produce a total population of 3,318,557 children with ADHD. The total annual 3,318,557 children with ADHD. The total annual cost of care would be $2.15 billion at an annual cost of care would be $2.15 billion at an annual cost of $649 per child. This result is similar to the cost of $649 per child. This result is similar to the estimates from Chan of an annual cost of care of estimates from Chan of an annual cost of care of $2.5 billion. The attributable cost of care for $2.5 billion. The attributable cost of care for ADHD was $154 per case for an annual cost of ADHD was $154 per case for an annual cost of care of $511,000 in North Dakota.care of $511,000 in North Dakota.

Documents

Children and Adolescents With Attention Deficit-Hyperactivity Disorder: 1. Prevalence and Cost of Care Larry Burd, PhD; Marilyn G. Klug, PhD; Matthew J