Document 7402333

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Transcript Document 7402333

The “Law of the Few” and
ADHD & Psychostimulants
(Adderall, Ritalin, Concerta)
1
Stanley Milgram and Our “Small-World”
• The Law of the Few: Certain people are critical to social epidemics.
Question: How are human beings connected?
“Small-World” research experiment
(e.g., from Omaha, Nebraska to a stockbroker in Massachusetts)
• Connectors: a very small number of special people—who thrive at
making innumerable “weak tie” acquaintances—and through whom
the rest of us are all linked (measure: # of Facebook friends?)
5 or 6 steps = “Six Degrees of Separation” because not all degrees
are equal
2
Background & Significance
So what? What is the significance of ADHD and psychostimulants?
– ADHD is the most commonly diagnosed behavioral disorder in
children, making up more than 50% of all child psychiatric diagnoses
– 75-85% of children diagnosed with ADHD are prescribed
psychostimulant drugs (e.g., Ritalin, Adderall, Concerta, Dexedrine)
– the U.S. population consumes 90% of the world’s production of
psychostimulants
– school-age children in the U.S. consume 4 times more psychiatric
medication than children in the rest of the world combined
3
Background & Significance
So what? What is the significance of ADHD and psychostimulants? cont’d . . .
– an estimated 3-5% of school-age children have the disorder (NIH
Consensus Statement, 1998); other estimates 4-12% (Vanderbilt, MUSC);
(1.5-to-6 million kids, 1-to-3 students in every classroom in the U.S.)
– ADHD prevalence estimates from actual community samples range from
as low as 1.7% (Calif. Bay Area) to as high as 26% (military bases near Virginia Beach)
– rates of psychostimulant use vary as much as 3-fold between states and
10-fold within them (Rappley et al., 1995; Wennberg & Wennberg, 2000; Zito et al., 1997)
– At the peak age for psychostimulant use, 11, almost 1 in every 9 boys in
the U.S. uses these drugs (Cox et al., Journal of Pediatrics, February 2003).
– big $$: approximately $3 billion spent in 2005 on ADHD related drugs
(new potential growth markets: pre-schoolers and adults)
4
DSM-IV Diagnostic Criteria for ADHD
Diagnostic and Statistical Manual of Mental Disorders, 4th edition (American Psychiatric Association)
Either (1) or (2)
(1). 6 (or more) of the following 9 symptoms of inattention have persisted for at least 6 months to a degree that
is maladaptive and inconsistent with developmental level:
Inattention
(a) often fails to give close attention to details or makes careless mistakes in schoolwork,
work, or other activities
(b) often has difficulty sustaining attention in tasks or play activities
(c) often does not seem to listen when spoken to directly
(d) often does not follow through on instructions and fails to finish schoolwork, chores, or
duties in the workplace (not due to oppositional behavior or failure to understand instructions)
(e) often has difficulty organizing tasks and activities
(f) often avoids, dislikes, or is reluctant to engage in tasks that require sustained mental effort
(such as schoolwork or homework).
(g) often loses things necessary for tasks or activities (e.g. toys, school assignments, pencils,
books, or tools)
(h) is often easily distracted by extraneous stimuli
(i) is often forgetful in daily activities
5
DSM-IV Diagnostic Criteria for ADHD
Diagnostic and Statistical Manual of Mental Disorders, 4th edition (American Psychiatric Association)
(2). 6 (or more) of the following 9 symptoms of hyperactivity-impulsivity have persisted for at least 6 months to
a degree that is maladaptive and inconsistent with developmental level:
Hyperactivity
(a) often fidgets with hands or feet or squirms in seat
(b) often leaves seat in classroom or in other situations in which remaining seated is expected
(c) often runs about or climbs excessively in situations in which it is inappropriate (in adolescents or
adults, may be limited to subjective feelings of restlessness)
(d) often has difficulty playing or engaging in leisure activities quietly
(e) is often "on the go" or often acts as if "driven by a motor"
(f) often talks excessively
Impulsivity
(g) often blurts out answers before questions have been completed
(h) often has difficulty awaiting turn
(i) often interrupts or intrudes on others (e.g. butts into conversations or games)
ADHD’s inherent subjectivity lends itself to criticisms of being a convenient social construct (for
“medicalizing” and medicating annoying behavior) and fuels the controversy over the disorder.
6
Four Aspects to the Controversy Over ADHD/Stimulants
1.
Allegation: ADHD is not a real disorder and could be part of a larger
feminist conspiracy to make little boys more like little girls.
etiology (its cause) is unknown and no independent medical test for diagnosing ADHD;
biology/nature vs. environment/nurture debate
2.
Allegation: ADHD is a conspiracy on the part of public schools to
warehouse kids instead of effectively teaching and disciplining them.
initial identification of ADHD is often by teachers or other school personnel in academic settings
3.
Allegation: Ritalin is really “kiddie cocaine” and parents who give their
kids these kinds of drugs are simply doping up their problem children.
psychostimulants are powerful, potentially addictive drugs susceptible to personal abuse and illegal diversion
(classified as Schedule II drugs by the DEA, along with Oxycontin and morphine)
4.
Allegation: ADHD is over-diagnosed and psychostimulants are overprescribed across the country.
number of ADHD diagnoses and psychostimulants Rx’s increased dramatically in the 1990s
7
Ritalin/ADHD’s Tipping Point (early 1990s)
• 400-500% increase in ADHD diagnoses in the 1990s
– 1991: 800,000 to 950,000 children diagnosed with ADHD
– 2001: 4 to 4.75 million children diagnosed with ADHD
• 800-900% increase in psychostimulant use in the 1990s
– 1991: 2 million psychostimulant prescriptions
– 2001: 21 million psychostimulant prescriptions
8
Per Capita Ritalin Use Over Time (1981-1996)
9
Ritalin/ADHD’s Tipping Point
10
Increased Public Awareness During Clinton Years
“As many of you know, the Journal of the American Medical Association recently
reported that the number of preschoolers, ages 2-4 who are taking psychotropic drugs
increased dramatically from 1991 to 1995 [200,000-300,000 or 1.5% of the total]. We
know that the increase for Ritalin alone was 150 percent, and the use of anti-depressants
increased over 200 percent. Now I am no doctor, as is obvious, but I am a parent and I
have been a longtime children’s advocate. And these findings concern me. I know they
concern Dr. Hyman [Director, NIMH], Secretary [Donna] Shalala and countless other
experts.”
The White House -- March 20, 2000
11
Public Policy Implications & Questions
• Over-diagnosis of ADHD (Are we “pathologizing” childhood?)
Does the U.S. have a monopoly of wisdom on diagnosing and treating ADHD? TYPE II error
• Over-use of psychostimulants (public health issue)
waste of limited resources; Society for Neuroscience findings, 2001
-------------------------------------------------------------------• Under-diagnosis of ADHD (public health/education issues)
Children with unmet mental health needs are more likely to suffer academically and developmentally.
TYPE I error
• Under-use of psychostimulants (public health/education issues)
Studies show that untreated ADHD can lead to increased self-medication and drug addiction.
12
Research Question
What explains the enormous variation
in psychostimulant consumption across the U.S.?
13
Methylphenidate and Amphetamine
Distribution, 2005 (DEA data)
(average = 4,150 grams/100,000 individuals)
grams/per 100,000 Individuals
0 to 1,600
Low
1,600 to 3,150 Below Average
3,150 to 5,150 Average
5,150 to 6,750 Above Average
6,750 to 8,350 High
8,350 to 11,000 Extremely High
14
(4.6%)
(25.5%)
(43.5%)
(19.6%)
(4.9%)
(1.8%)
National Profile of Psychostimulant Use
Data Set: DEA’s Automation of Reports & Consolidated Orders System (ARCOS)
-
access via Freedom of Information Act
(chocolates and flowers helped expedite an otherwise extraordinarily tedious and time-consuming process)
-
not a sample: tracks every ounce of psychostimulant distribution in the U.S.
from its point of manufacture through commercial distribution channels to points
of sale at the dispensing/retail level: hospitals, pharmacies, practitioners and
academic medical centers
15
Characteristics of Counties with High and Low Use of Psychostimulants, DEA ARCOS data
* difference in means significant at the .10 level, ** at the .05 level, *** at the .01 level
Variable
Distribution Rate (Grams of Psychostimulant/per 100K)***
Socio-demographic and Economic
Characteristics
Total Population***
Per Capita Income***
Unemployment Rate***
% of Pop. With Some Form of Health Insurance***
White Population as Percentage of Total Population**
Black Population as Percentage of Total Population
Asian Population as Percentage of the Total Population
State has Schedule II Rx Monitoring Program***
Children/Adolescents as a % of the Population***
Mean for all
U.S. Counties
Low Consumption
n=1,015 counties
High Consumption
n=1,015 counties
(Standard Error)
(Standard Error)
(Standard Error)
3,359 grams
1,796 grams
4,923 grams
(37.31)
(20.72)
(43.50)
89,327
65,680
114,000
(52.22)
(86.25)
(59.34)
$21,397
$20,118
$22,760
(130.8)
(159.2)
(204.6)
4.9%
5.4%
4.4%
(0.049)
(0.079)
(0.055)
82.9%
82.1%
83.7%
(0.10)
(0.137)
(0.131)
87.9%
87.1%
88.6%
(0.290)
(0.455)
(0.362)
9.7%
10.2%
9.4%
(0.280)
(0.438)
(0.352)
2.45%
2.5%
2.4%
(0.280)
(0.441)
(0.358)
30.7%
34.3%
27.0%
(0.008)
(0.012)
(0.012)
29.0%
29.2%
28.8%
(0.061)
(0.10)
(0.075)
16
Characteristics of Counties with High and Low Use of Psychostimulants, DEA ARCOS data
* difference in means significant at the .10 level, ** at the .05 level, *** at the .01 level
Variable
Educational
Characteristics
Students--to--Teacher Ratio***
Private Students--to--Public Students Ratio***
Private Coed--to--Private Non-Coed Students***
Private Sectarian--to--Private Non-Sectarian Students***
HMO Penetration (% of Individuals Enrolled in HMOs)***
Health System Characteristics
Number of HMOs Operating in a County***
MDs/per 100,000 Individuals***
Child Psychiatrists as Percentage of Total MDs***
Psychiatrists as Percentage of Total MDs***
GPs, FPs as Percentage of Total MDs***
Pediatricians as Percentage of Total MDs***
Neurologists as Percentage of Total MDs***
Female MDs--to--Male MDs Ratio
Young MDs(<55)--to--Senior MDs(>55) Ratio***
Mean for all
U.S. Counties
Low Consumption
n=1,015 counties
High Consumption
n=1,015 counties
(Standard Error)
(Standard Error)
(Standard Error)
14.6
14.3
14.8
(0.048)
(0.070)
(0.066)
.058
.043
.069
(0.001)
(0.0018)
(0.002)
58.0
38.0
68.3
(8.609)
(8.092)
(12.33)
23.8
14.5
28.5
(2.755)
(2.072)
(3.990)
12.1%
10.2%
14.1%
(0.248)
(0.322)
(0.374)
3.9
3.4
4.5
(0.069)
(0.092)
(0.101)
112
86
139
(2.690)
(3.50)
(4.00)
0.4%
0.3%
0.5%
(0.026)
(0.038)
(0.036)
3.0%
2.5%
3.4%
(0.099)
(0.149)
(0.119)
41.1%
47.7%
34.7%
(0.515)
(0.757)
(0.662)
5.5%
4.9%
6.1%
(0.129)
(0.200)
(0.166)
0.9%
0.7%
1.1%
(0.046)
(0.085)
(0.039)
.210
.210
.210
(0.004)
(0.006)
(0.004)
1.8
1.6
1.9
(0.023)
(0.035)
(0.030)
17
Main Limitation of Existing Studies: Generalizability
Most of what we know about ADHD is based on local community
studies of children with the disorder.
Thus, to date we have relied primarily on massive meta-analyses
and the NIH funded Multimodal Treatment Study of ADHD
(MTA) to cobble together a national profile of the child
population diagnosed with ADHD.
18
A National Profile of Children Diagnosed with ADHD
Data Set: National Health Interview Survey (NHIS)
-
nationally representative, cross-sectional health survey conducted
jointly by the National Center for Health Statistics (NCHS) and the
Centers for Disease Control & Prevention (CDC)
-
sample size: 37,573 households; 97,059 persons in 38,171 families
-
child component: 12,910 children less than 18 years old;
response rate, 91%
-
survey question: “Has a doctor or a health professional ever told you that
[child’s name] has ADHD?”
19
Characteristics of Children Diagnosed with ADHD
* difference in means significant at the .10 level, ** at the .05 level, *** at the .01 level
Variable
Demographic
Male***
Female***
Age (mean)***
Birth Weight (mean in ounces)**
White***
Black**
Asian***
Geographic Region
Northeast**
Midwest
South***
West***
Overall Mean
(S.E.)
ADHD? Yes
(n=590, 5%)^
ADHD? No
(n=10,728, 95%)^
.512
.767
.498
(.005)
(.020)
(.006)
.488
.233
.502
(.005)
(.020)
(.006)
9.52
11.7
9.39
(.056)
(.150)
(.052)
118.4
116.1
118.7
(.227)
(1.06)
(.253)
.766
.838
.764
(.006)
(.017)
(.006)
.153
.117
.156
(.005)
(.015)
(.005)
.081
.045
.080
(.003)
(.009)
(.003)
.184
.147
.186
(.005)
(.019)
(.006)
.251
.273
.250
(.007)
(.021)
(.007)
.352
.423
.348
(.007)
(.026)
(.007)
.212
.157
.215
(.006)
(.018)
(.006)
20
Characteristics of Children Diagnosed with ADHD
* difference in means significant at the .10 level, ** at the .05 level, *** at the .01 level
Variable
Family
# of persons in the family (mean)***
Relationship with Parents
Mother: biological***
Mother: step, adoptive, foster, none***
Parents Present
Mother and Father***
Mother, no Father***
Father, no Mother
Neither Mother nor Father*
Parents’ Marital Status
Married***
Divorced/Separated/Never Married/Widowed***
Mother’s Highest Level of Education
Less Than College
College Degree or More***
Overall Mean
(S.E.)
ADHD? Yes
(n=590, 5%)^
ADHD? No
(n=10,728, 95%)^
4.43
4.12
4.46
(.019)
(.061)
(.021)
.965
.900
.965
(.002)
(.015)
(.002)
.035
.100
.034
(.002)
(.015)
(.002)
.706
.604
.709
(.006)
(.024)
(.006)
.226
.286
.225
(.005)
(.022)
(.005)
.041
.060
.040
(.002)
(.011)
(.002)
.027
.050
.026
(.002)
(.010)
(.002)
.754
.640
.758
(.005)
(.025)
(.006)
.246
.360
.242
(.005)
(.025)
(.006)
.768
.830
.768
(.005)
(.020)
(.005)
.232
.170
.232
(.004)
(.020)
(.005)
21
Mayes, Bokhari, Scheffler, 2005
Conditional Probability of a Child Being Diagnosed with ADHD
0.2000
White Male Child
Male Child w/o Bio Mom
Male Child w/o Dad in House
White Male Child w/o Bio Mom
White Male Child w/o Bio Mom & w/o Dad In House
0.1500
0.1000
0.0500
0.0000
2
3
4
5
6
7
8
Family Size
22