Controlled Substance Prescribing
Trends and Physician and Pharmacy
Utilization Patterns: Epidemiological
Analysis of the Maine Prescription
Monitoring Program, 2006 - 2010
Kenneth McCall, PharmD
Chunhao Tu, PhD
Matthew Lacroix, PharmD
Kevin Wallace, MD
Christina Holt, MD
Jonathan Balk, PharmD Candidate
Outline
• Background
• Pharmacoepidemiological PMP Analysis
– Methods
– Prescription trends from 2006-2010
– Physician and pharmacy utilization patterns
• Future Directions
BACKGROUND
Maine PMP Overview
• Established in 2004
• Data from over 300 retail and mail-order
pharmacies licensed to dispense in Maine
• Data submitted at least twice per month.
• Data available to health care professionals (e.g.,
pharmacists and prescribers) online (after
registration – only 40% of prescribers and 15% of
pharmacists)
• Quarterly threshold reports sent to prescribers
www.maine.gov/pmp
4
Non-heroin opiate admissions by state per 100,000
population aged 12 and older: 1998-2008
MAINE LEADS THE NATION IN
ADMISSIONS FOR PRESCRIPTION
OPIOID ABUSE
Non-heroin opiate admissions by state per 100,000
population aged 12 and older: 1998-2008
Source: Center for Behavioral Health Statistics and Quality, Substance Abuse and Mental Health Services Administration,
Treatment Episode Data Set (TEDS), Data received through 8.31.09.
Non-heroin opiate admissions by state per 100,000
population aged 12 and older: 1998-2008
Source: Center for Behavioral Health Statistics and Quality, Substance Abuse and Mental Health Services Administration,
Treatment Episode Data Set (TEDS), Data received through 8.31.09.
Non-heroin opiate admissions by state per 100,000
population aged 12 and older: 1998-2008
Source: Center for Behavioral Health Statistics and Quality, Substance Abuse and Mental Health Services Administration,
Treatment Episode Data Set (TEDS), Data received through 8.31.09.
MAINE LEADS THE NATION IN
ADMISSIONS FOR PRESCRIPTION
OPIOID ABUSE
IN MAINE, THERE WERE MORE
ADMISSIONS FOR PRESCRIPTION OPIOID
ABUSE IN 2010 THAN FOR ALCOHOL
Poisoning deaths involving opioid analgesics,
cocaine, and heroin: US, 1999-2006
Death rates for poisonings involving opioid analgesics:
Comparison of state and US rates: 2006
IN MAINE, THERE ARE MORE DEATHS
EACH YEAR FROM OPIOID POSIONING
THAN FROM AUTOMODILE ACCIDENTS
Pharmacoepidemiological PMP Analysis
Methods
• Design
– Retrospective dataset analysis.
– The Maine PMP began in 2004 and collects Schedule
II, III, and IV new and refill prescription information
from licensed pharmacies.
– Individuals who received one or more controlled
substance prescriptions from a licensed pharmacy
during state fiscal years 2006 to 2010 (July 1, 2005 to
June 30, 2010; herein referred to by year only) are
included in the study population.
– Data was cleaned and coded prior to analysis.
Methods
• Analysis
– The two-sided Welch’s two-sample t test was used to
compare the difference between two groups for
continuous variables.
– The Chi-square test was applied to examine the statistical
association between two categorical variables and equal
proportions, and the Cochran-Mantel-Haenszel (CMH) test
was used to examine the associations between classes for
multiple categorical data groups.
– The association between ordinal variables13 was measured
using gamma statistics () with corresponding 95%
confidence interval (CI) and significance testing for
temporal trends was performed with the CochranArmitage test.
PRESCRIPTION TRENDS FROM
2006-2010
Unique Patients Per Year
Maine PMP
Number of Unique Patients
445000
403289
411822
426806
434942
433972
2007
2008
2009
2010
437500
430000
422500
415000
407500
400000
2006
Patients / Year
Trend Line
Number of unique patients per year
increased by 31,653 from 2006-2009,
while the US census bureau estimates
the Maine population only grew by
around 5,000
Number of Prescriptions by Drug Enforcement
Agency (DEA) Class, Maine PMP Data, 2006-2010
22.4% Increase, P < 0.001
3,000,000
2,500,000
CIV
2,000,000
CIII
CII
1,500,000
1,000,000
28.6%
Increase,
P < 0.001
500,000
0
2006
2007
2008
2009
2010
Prescriptions for controlled drugs
increased by 22.4% in 5 years, whereas
the estimated Maine population only
increased by 0.4%.
Class II drugs, which have the highest
potential for abuse, had the greatest
rate of increase in prescriptions among
DEA classes from 2006 to 2010.
Frequency of Prescriptions by Drug Category,
Maine PMP Data, 2006 & 2010
Prescriptions (2006)
Prescriptions (2010)
Narcotics
Hypnotics
Narcotics
Hypnotics
Stimulants
Other
Stimulants
Other
0%
1%
10%
35%
13%
55%
36%
50%
Narcotics are the most frequently
prescribed drug category and stimulants
are the fastest growing drug category.
Narcotic Prescriptions, Maine PMP,
2006-2010
Fiscal Year
# of Rxs
2006
1,125,323
2007
1,177,114
2008
1,250,582
2009
1,271,667
2010
1,268,242
12.7%
Increase
P < 0.001
Days-Supply / Rx
mean (SD)
13.34
(12.50)
13.88
(12.66)
14.52
(12.82)
15.19
(13.48)
15.57
(13.45)
16.7%
Increase
P < 0.001
Hypnotic Prescriptions, Maine PMP,
2006-2010
Fiscal Year
# of Rxs
2006
707,793
2007
756,992
2008
830,105
2009
882,343
2010
904,723
27.8%
Increase
P < 0.001
Days-Supply / Rx
mean (SD)
26.11
(17.03)
26.70
(17.37)
27.34
(17.99)
28.12
(19.32)
28.67
(19.60)
9.8%
Increase
P < 0.001
Stimulant Prescriptions, Maine PMP,
2006-2010
Fiscal Year
# of Rxs
2006
207,242
2007
228,209
2008
260,797
2009
287,547
2010
319,001
54.1%
Increase
P < 0.001
Days-Supply / Rx
mean (SD)
30.64
(11.02)
30.75
(11.05)
30.99
(11.59)
31.51
(12.83)
31.20
(13.18)
2.8%
Increase
P < 0.001
The mean days-supply per prescription
has significantly increased for all
controlled drug categories; narcotics,
hypnotics, and stimulants.
Oxycodone Prescriptions, Maine PMP,
2006-2010
Fiscal Year
# of Rxs
Mean Dose
Strength (mg)
2006
150,504
14.45
2007
183,877
15.04
48.1%
Increase
P < 0.001
2008
206,113
14.97
2009
194,615
16.37
2010
222,804
15.56
7.7%
Increase
P < 0.001
Alprazolam Prescriptions, Maine PMP,
2006-2010
Fiscal Year
# of Rxs
Mean Dose
Strength (mg)
2006
135,774
0.601
2007
140,471
0.619
14.1%
Increase
P < 0.001
2008
147,916
0.631
2009
150,752
0.649
2010
154,842
0.668
11.1%
Increase
P < 0.001
Amphetamine/dextroamphetamine
Prescriptions, Maine PMP, 2006-2010
Fiscal Year
# of Rxs
Mean Dose
Strength (mg)
2006
73,983
17.61
2007
83,831
18.02
59.2%
Increase
P < 0.001
2008
98,491
18.15
2009
107,099
18.33
2010
117,758
18.51
5.1%
Increase
P < 0.001
The mean dose per tablet of
oxycodone, alprazolam, and
amphetamine/dextroamphetamine
has significantly increased.
Percent increase in Controlled Substance Rxs, CII Rxs, Dayssupply per Rx (narcotics), and Strength per dose (oxycodone):
Indexed to 2006 Levels
Maine PMP Data
1.4
1.29
1.3
1.22
1.2
1.17
2006
1.08
1.1
1
1
1
1
1
2007
2008
2009
2010
0.9
0.8
CS Rxs
CII Rxs
Days Supply
Strength
GRAMS of amphetamine/dextroamphetamine and oxycodone
dispensed each year: Maine PMP Data, 2006-2010
Amphetamine
Oxycodone
58.5% Increase, P < 0.001
308131
284432
274672
242728
194382
53.1% Increase, P < 0.001
63318
2006
71362
2007
83588
2008
88124
2009
96900
2010
In 2010, more than 300,000 grams of
oxycodone and nearly 100,00 grams of
amphetamine were dispensed to
patients in Maine. Compared to 2006,
this represents a significant 58.5% and
53.1% increase, respectively.
PHYSICIAN AND PHARMACY
UTILIZATION PATTERNS
Distribution of individuals (number/%) receiving controlled prescriptions
by number of prescribers and number of pharmacies in 2010
Number of
Prescribers
Used
Number of Pharmacies Used
1
2
3
4
>5
Total
1
246,386
16,224
2,874
655
312
266,451
2
56.79
61,498
3.74
24,732
0.66
4,349
0.15
1,049
0.07
492
61.42
92,120
3
14.17
20,790
5.70
12,030
1.00
4,187
0.24
1,171
0.11
584
21.23
38,762
4
4.79
7,802
2.77
5,723
0.97
2,736
0.27
1,000
0.13
569
8.93
17,830
>5
1.80
5,359
1.32
5,450
0.63
3,643
0.23
2,064
0.13
2,172
4.11
18,688
1.24
341,835
1.26
64,159
0.84
17,789
0.48
5,939
0.50
4,129
4.31
433,851
78.79
14.79
4.10
1.37
0.95
100.00
Total
• Most individuals (82.7%) obtained their
prescriptions for controlled drugs from one or
two prescribers in 2010.
Distribution of individuals (number/%) receiving controlled prescriptions
by number of prescribers and number of pharmacies in 2010
Number of
Prescribers
Used
Number of Pharmacies Used
1
2
3
4
>5
Total
1
246,386
16,224
2,874
655
312
266,451
2
56.79
61,498
3.74
24,732
0.66
4,349
0.15
1,049
0.07
492
61.42
92,120
3
14.17
20,790
5.70
12,030
1.00
4,187
0.24
1,171
0.11
584
21.23
38,762
4
4.79
7,802
2.77
5,723
0.97
2,736
0.27
1,000
0.13
569
8.93
17,830
>5
1.80
5,359
1.32
5,450
0.63
3,643
0.23
2,064
0.13
2,172
4.11
18,688
1.24
341,835
1.26
64,159
0.84
17,789
0.48
5,939
0.50
4,129
4.31
433,851
78.79
14.79
4.10
1.37
0.95
100.00
Total
• Most individuals (93.6%) received their
prescribed controlled drugs from one or two
pharmacies in 2010.
Distribution of individuals (number/%) receiving controlled prescriptions
by number of prescribers and number of pharmacies in 2010
Number of
Prescribers
Used
Number of Pharmacies Used
1
2
3
4
>5
Total
1
246,386
16,224
2,874
655
312
266,451
2
56.79
61,498
3.74
24,732
0.66
4,349
0.15
1,049
0.07
492
61.42
92,120
3
14.17
20,790
5.70
12,030
1.00
4,187
0.24
1,171
0.11
584
21.23
38,762
4
4.79
7,802
2.77
5,723
0.97
2,736
0.27
1,000
0.13
569
8.93
17,830
>5
1.80
5,359
1.32
5,450
0.63
3,643
0.23
2,064
0.13
2,172
4.11
18,688
1.24
341,835
1.26
64,159
0.84
17,789
0.48
5,939
0.50
4,129
4.31
433,851
78.79
14.79
4.10
1.37
0.95
100.00
Total
• The vast majority of individuals who used only
one prescriber also used a single pharmacy
(92.5%).
Distribution of individuals (number/%) receiving controlled prescriptions
by number of prescribers and number of pharmacies in 2010
Number of
Prescribers
Used
Number of Pharmacies Used
1
2
3
4
>5
Total
1
246,386
16,224
2,874
655
312
266,451
2
56.79
61,498
3.74
24,732
0.66
4,349
0.15
1,049
0.07
492
61.42
92,120
3
14.17
20,790
5.70
12,030
1.00
4,187
0.24
1,171
0.11
584
21.23
38,762
4
4.79
7,802
2.77
5,723
0.97
2,736
0.27
1,000
0.13
569
8.93
17,830
>5
1.80
5,359
1.32
5,450
0.63
3,643
0.23
2,064
0.13
2,172
4.11
18,688
1.24
341,835
1.26
64,159
0.84
17,789
0.48
5,939
0.50
4,129
4.31
433,851
78.79
14.79
4.10
1.37
0.95
100.00
Total
• The greater the number of prescribers, the
more likely the prescription recipient used a
greater number of pharmacies ([ = 0.711;
95% CI = (0.709, 0.714)]).
Number and percent of Schedule II, III, or IV prescription
recipients who used five or more physicians, five or more
pharmacies, either or both in 2010.
DEA Class
II
III
IV
>5 Prescribers
>5
Pharmacies
4,534
3.00%
3,429
1.53%
2,011
0.98%
1,808
1.19%
649
0.29%
554
0.27%
>5 Prescribers >5 Prescribers
OR >5
AND >5
Pharmacies
Pharmacies
5,744
598
3.81%
0.40%
3,766
312
1.69%
0.14%
2,382
183
1.16%
0.09%
A significantly greater percentage of individuals taking Schedule II drugs used five
or more prescribers and/or five or more pharmacies than those taking only
Schedule III or IV drugs (P<0.001).
Future Directions
•
•
•
•
Geographic analysis
Data linkages with state mortality data
Pediatric and Geriatric prescribing trends
Prescribing trends among prescribers who are
registered with PMP versus prescribers who
are not registered
QUESTIONS?