Children and Adolescents With Attention Deficit-Hyperactivity Disorder: 1. Prevalence and Cost of Care

1
Children and Adolescents With Attention
Deficit-Hyperactivity Disorder 1. Prevalence and
Cost of Care

• Larry Burd, PhD Marilyn G. Klug, PhD Matthew J.
  Coumbe, PhD Jacob Kerbeshian, MD

2
Abstract

• The objective of this study was to use
  population-based data to estimate the prevalence
  and cost of treatment for attention-deficit
  hyperactivity disorder (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 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 children with
  ADHD with publicly funded payers was increased 25
  to 175 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 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 to ADHD. In the
  United States, the cost of care attributable to
  children with ADHD would be 2.15 billion
  annually. (J Child Neurol 200318555-561).

3

• Current Study
• In this study, we used the health claims data
  from the North Dakota Department of Health, to
  determine
• the administrative prevalence of ADHD in the
  state of North Dakota
• differences in cost of care for children and
  adolescents with ADHD compared with
  the subjects who do not have ADHD, and
• differences in prevalence and cost by payer type
  (private coverage or publicly funded health
  insurance).

4
Inclusion Criteria Cases

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

5
Inclusion CriteriaControls

• The controls were all remaining subjects 0 to 21
  years of age in the database who did not have an
  ICD-9 code of 314.00, 314.01, or 314.8 or the
  DSM-IV code 314.9 in their diagnostic
  formulation.
• In this sample, we had 24.5 controls for each
  case.

6
Limitations

• The data are from North Dakota, a small rural
  state with a total population in 1997 of 650,000.
  The data for this study are health care claims
  data and might reflect coding error or bias.
• Two significant populations not represented in
  these data were uninsured children and the Native
  American population.

7
Calculation of Costs

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

8
Graph of prevalence by age and gender (male,
female, and total group).
9
Graph of prevalence rate in percentage by age of
cohort and payer type (public, private, or total
group).
10
Comparison of Mean (1996-1997) Costs Between
Children With ADHD and Without (Controls) by
Payment Method
HCFA
Annual Mean
Mean Cost per
N Cost Visit
Total 98,991
ADHD 3872 648.55 158.59
Controls 95,119 494.53 112.10
Private 80,819
ADHD 2801 568.79 155.79
Controls 78,018 503.11 113.23
Public 18,172
ADHD 1071 856.03 166.37
Controls 17,101 480.07 109.84
Mean costs of children with ADHD significantly
higher than those of controls (Plt.01) ADHD
attention-deficit hyperactivity disorder HFCA
Health Care Financing Administration
11
Comparison of Mean (1996-1997) Costs Between
Children With ADHD and Without (Controls) by
Gender
HFCA
Annual Mean
Mean Cost per
N Cost Visit
Male 48,760
ADHD 2908 612.36 156.91
Controls 45,852 491.81 113.55
Female 50,231
ADHD 964 757.92 163.66
Controls 49,267 497.12 110.75
Mean costs of children with ADHD significantly
higher than those of controls (Plt.01) ADHD
attention-deficit hyperactivity disorder HFCA
Health Care Financing Administration
12
Comparison of Mean (1996-1997) Costs Between
Children With ADHD and Without (Controls) by
Payment Method
Inpatient Outpatient
Annual Mean Annual Mean
Mean Cost per Mean Cost per
Cost Visit N Cost Visit
Total 25,553
ADHD 8861.48 5702.43 613 1597.31 577.98
Controls 5528.89 3942.54 24,920 644.29 288.24
Private 11,872
ADHD 9592.39 5881.46 142 1815.32 879.29
Controls 5703.71 3929.51 11,730 766.21 394.97
Public 13,661
ADHD 8717.90 5681.21 471 1527.57 497.48
Controls 5468.87 3937.16 13,190 553.78 196.79
Mean cost of children with ADHD significantly
higher than those of controls (Plt.01) ADHD
attention-deficit hyperactivity disorder HFCA
Health Care Financing Administration
13
Comparison of Mean (1996-1997) Costs Between
Children With ADHD and Without (Controls) by
Gender
Inpatient Outpatient
Annual Mean Annual Mean
Mean Cost per Mean Cost per
Cost Visit N Cost Visit
Male 12,617
ADHD 9102.72 5947.87 468 1470.68 559.64
Controls 6811.52 4467.20 12,149 642.20 296.08
Female 12,916
ADHD 8156.47 4996.10 145 2014.96 639.31
Controls 4664.75 3886.29 12,771 646.30 280.79
Mean cost of children with ADHD significantly
higher than those of controls (Plt.01) ADHD
attention-deficit hyperactivity disorder HFCA
Health Care Financing Administration
14
Results

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

15
Mean Cost Comparisons

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

16
Proportion of Mean (1996-1997) Annual Number of
Visits Between Children With ADHD and Without
(Controls) by Payment Type
HCFA
Number
N Of Visits
Total 98,991 337,141
ADHD 3872 3.9 13,779 4.1
Controls 95,119 96.1 323,362 95.9
Private 80,819 274,389
ADHD 2801 3.5 8740 3.2
Controls 78,018 96.5 265,649 96.8
Public 18,172 62,752
ADHD 1071 5.9 5039 8.0
Controls 17,101 94.1 57,713 92.0
Significant increase in proportion of number of
visits for children with ADHD compared with
proportion of children with ADHD in the sample
(Plt.01) ADHD attention-deficit hyperactivity
disorder HCFA Health Care Financing
Administration
17
Proportion of Mean (1996-1997) Annual Number of
Visits Between Children With ADHD and Without
(Controls) by Gender
HFCA
Number
N Of Visits
Male 48,760 159,364
ADHD 2908 6.0 9785 6.0
Controls 45,852 94.0 149,579 94.0
Female 50,231 177,777
ADHD 964 1.9 3994 1.9
Controls 49,267 98.1 173,783 97.8
Significant increase in proportion of number of
visits for children with ADHD compared with
proportion of children with ADHD in the sample
(Plt.01) ADHD attention-deficit hyperactivity
disorder HCFA Health Care Financing
Administration
18
Proportion of Mean (1996-1997) Annual Number of
Visits Between Children With ADHD and Without
(Controls) by Payment Type
Inpatient
Number
N Of Visits
Total 4614 6053
ADHD 183 4.0 356 5.9
Controls 4431 96.0 5697 94.1
Private 2012 2674
ADHD 40 2.0 63 2.4
Controls 1972 98.0 2611 97.6
Public 2602 3379
ADHD 143 5.5 293 8.7
Controls 2459 94.5 3086 91.3
Significant increase in proportion of number of
visits for children with ADHD compared with
proportion of children with ADHD in the sample
(Plt.01) ADHD attention-deficit hyperactivity
disorder HCFA Health Care Financing
Administration
19
Proportion of Mean (1996-1997) Annual Number of
Visits Between Children With ADHD and Without
(Controls) by Gender
Inpatient
Number
N Of Visits
Male 1959 2682
ADHD 134 6.8 263 9.8
Controls 1825 93.2 2419 90.2
Female 2655 3371
ADHD 49 1.8 93 2.8
Controls 2606 98.2 3278 97.2
Significant increase in proportion of number of
visits for children with ADHD compared
with proportion of children with ADHD in
the sample (Plt.01) ADHD attention-deficit
hyperactivity disorder HCFA Health Care
Financing Administration
20
Proportion of Mean (1996-1997) Annual Number of
Visits Between Children With ADHD and Without
(Controls) by Payment Type
Outpatient
Number
N Of Visits
Total 25,533 67,088
ADHD 613 2.4 2889 4.3
Controls 24,920 97.6 64,199 95.7
Private 11,872 20,370
ADHD 142 1.2 291 1.4
Controls 11,730 98.8 20,079 98.6
Public 13,661 46,718
ADHD 471 3.4 2598 5.6
Controls 13,190 96.6 44,120 94.4
Significant increase in proportion of number of
visits for children with ADHD compared with
proportion of children with ADHD in the sample
(Plt.01) ADHD attention-deficit hyperactivity
disorder HCFA Health Care Financing
Administration
21
Proportion of Mean (1996-1997) Annual Number of
Visits Between Children With ADHD and Without
(Controls) by Gender
Outpatient
Number
N Of Visits
Male 12,617 31,811
ADHD 468 3.7 2084 6.6
Controls 12,149 96.3 29,727 93.4
Female 12,916 35,277
ADHD 145 1.1 805 2.3
Controls 12,771 98.9 34,472 97.7
Significant increase in proportion of number of
visits for children with ADHD compared with
proportion of children with ADHD in the sample
(Plt.01) ADHD attention-deficit hyperactivity
disorder HCFA Health Care Financing
Administration
22
Inpatient Data

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

23
Outpatient Data

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

24
Public Payer Type

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

25
Private Payer Type

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

26
Comparison of Mean (1996-1997) Total Annual Costs
Between Children With ADHD and Without (Controls)
by Payment Method, Gender, and Age Groups
HCFA
N Cost
Total 98,991 48,359,948
ADHD 3872 3.9 2,546,024 5.3
Controls 95,119 96.1 45,813,924 94.7
Private 80,819 39,072,153
ADHD 2801 3.5 1,609,533 4.1
Controls 78,018 96.5 37,462,620 95.9
Public 18,172 9,287,796
ADHD 1071 5.9 936,492 10.1
Controls 17,101 94.1 8,351,304 89.9
Significant increase in proportion of total cost
for children with ADHD compared with proportion
of children with ADHD in the sample (Plt.01) ADHD
attention-deficit hyperactivity disorder HCFA
Health Care Financing Administration
27
Comparison of Mean (1996-1997) Total Annual Costs
Between Children With ADHD and Without (Controls)
by Payment Method, Gender, and Age Groups
HCFA
N Cost
Male 48,760 23,700,450
ADHD 2908 6.0 1,803,345 7.6
Controls 45,852 94.0 21,897,105 92.4
Female 50,231 24,659,498
ADHD 964 1.9 742,679 3.0
Controls 49,267 98.1 23,916,819 97.0
Significant increase in proportion of total cost
for children with ADHD compared with proportion
of children with ADHD in the sample (Plt.01) ADHD
attention-deficit hyperactivity disorder HCFA
Health Care Financing Administration
28
Comparison of Mean (1996-1997) Total Annual Costs
Between Children With ADHD and Without (Controls)
by Payment Method, Gender, and Age Groups
Inpatient
N Cost
Total 4614 25,912,447
ADHD 183 4.0 1,628,127 6.3
Controls 4431 96.0 24,284,320 93.7
Private 2012 11,203,147
ADHD 40 2.0 367,648 3.3
Controls 1972 98.0 10,835,499 96.7
Public 2602 14,709,301
ADHD 143 5.5 1,260,479 8.6
Controls 2459 94.5 13,448,822 91.4
Significant increase in proportion of total cost
for children with ADHD compared with proportion
of children with ADHD in the sample (Plt.01) ADHD
attention-deficit hyperactivity disorder
29
Comparison of Mean (1996-1997) Total Annual Costs
Between Children With ADHD and Without (Controls)
by Payment Method, Gender, and Age Groups
Inpatient
N Cost
Male 1959 13,337,729
ADHD 134 6.8 1,233,750 9.2
Controls 1825 93.2 12,143,979 90.8
Female 2655 12,534,718
ADHD 49 1.8 394,377 3.1
Controls 2606 98.2 12,140,341 96.9
Significant increase in proportion of total cost
for children with ADHD compared with proportion
of children with ADHD in the sample (Plt.01) ADHD
attention-deficit hyperactivity disorder
30
Comparison of Mean (1996-1997) Total Annual Costs
Between Children With ADHD and Without (Controls)
by Payment Method, Gender, and Age Groups
Outpatient
N Cost
Total 25,533 17,050,071
ADHD 613 2.4 991,152 5.8
Controls 24,920 97.6 16,058,919 94.2
Private 11,872 8,941,555
ADHD 142 1.2 256,992 2.9
Controls 11,730 98.8 8,684,563 97.1
Public 13,661 8,108,516
ADHD 471 3.4 734,160 9.1
Controls 13,190 96.6 7,374,356 90.9
Significant increase in proportion of total cost
for children with ADHD compared with
proportion of children with ADHD in the sample
(Plt.01) ADHD attention-deficit hyperactivity
disorder
31
Comparison of Mean (1996-1997) Total Annual Costs
Between Children With ADHD and Without (Controls)
by Payment Method, Gender, and Age Groups
Outpatient
N Cost
Male 12,617 8,493,406
ADHD 468 3.7 699,253 8.2
Controls 12,149 96.3 7,794,153 91.8
Female 12,916 8,556,554
ADHD 145 1.1 291,898 3.4
Controls 12,771 98.9 8,264,766 96.6
Significant increase in proportion of total cost
for children with ADHD compared with proportion
of children with ADHD in the sample (Plt.01) ADHD
attention-deficit hyperactivity disorder
32
Comparisons of Number of Visits

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

33
Comparisons of Total Cost

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

34
Mean Attributable Cost of Health Care to Children
With ADHD in North Dakota for 1996 and 1997 by
HCFA Dataset
HFCA
Payer Group N Mean Attributable Cost Total Attributable Cost
Private 2801 66 184,866
Public 1071 376 402,969
Total 3872 154 591,668
ADHD attention-deficit hyperactivity disorder
HCFA Health Care Financing Administration
35
Mean Attributable Cost of Health Care to Children
With ADHD in North Dakota for 1996 and 1997 by
Inpatient Dataset
Inpatient
Payer Group n Mean Attributable Cost Total Attributable Cost
Private 40 3888 155,420
Public 143 3249 464,607
Total 183 3332 609,756
ADHD attention-deficit hyperactivity disorder
HCFA Health Care Financing Administration
36
Mean Attributable Cost of Health Care to Children
With ADHD in North Dakota for 1996 and 1997 by
Outpatient Dataset
Outpatient
Payer Group N Mean Attributable Cost Total Attributable Cost
Private 142 1049 148,958
Public 471 974 458,754
Total 613 1049 584,189
ADHD attention-deficit hyperactivity disorder
HCFA Health Care Financing Administration
37
Policy Implications

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

38
Policy Implications

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

39
Policy Implications

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

40
Policy Implications

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

41
Policy Implications

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