NSW Bureau of Crime Statistics and Research

Did the heroin shortage increase

amphetamine use in NSW?Lucy Snowball, Steve Moffatt, Don Weatherburn

and Melissa Burgess

Background

• Dec 2000/Jan 2001: significant reduction in heroin supply, purity and increase in cost– Onset of ‘heroin shortage’

• Concerns about drug substitution– Cocaine and amphetamines (ATS)

• Fears about ATS– Effects (psychosis, violence, depression)

– Australian treatment methods centred around heroin addiction

Previous studies

• Previous research has found mixed results:– Darke et al (2006) found a drop in ATS use– Maher (2007), Longo (2004) found an increase

• Previous research has been hampered by unrepresentative samples and low sample sizes

Current study

• Aim: To determine whether there was evidence of a switch from heroin to ATS as a result of the heroin shortage

• Data: use/possess series for narcotics and amphetamines, Jan 1995 – Sept 2007

• Method: Vector auto regression (VAR) and ARIMA modelling

Methodological issues

• Narcotics use/possess as a proxy for heroin?

• Are use/possess arrests a good indicator for drug use?

Emergency admissions vs. Arrests rates: Heroin

Figure 1a: Quarterly heroin-related hospital presentations and use/possess narcotics arrests, March qtr 1998 - March qtr 2007

0

100

200

300

400

500

600

700

800

900

1000

Mar

-98

Sep

-98

Mar

-99

Sep

-99

Mar

-00

Sep

-00

Mar

-01

Sep

-01

Mar

-02

Sep

-02

Mar

-03

Sep

-03

Mar

-04

Sep

-04

Mar

-05

Sep

-05

Mar

-06

Sep

-06

Mar

-07

Hospital admissions (Heroin)

Use/possess incidents (Narcotics)

Emergency admissions vs. Arrest rates: ATS

Figure 1b: Quarterly amphetamine-related hospital prsentations and amphetamines use/possess arrests, March qtr 1998 - March qt 2007

0

20

40

60

80

100

120

140

160

180

Mar

-199

8

Sep

-199

8

Mar

-199

9

Sep

-199

9

Mar

-200

0

Sep

-200

0

Mar

-200

1

Sep

-200

1

Mar

-200

2

Sep

-200

2

Mar

-200

3

Sep

-200

3

Mar

-200

4

Sep

-200

4

Mar

-200

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Sep

-200

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Mar

-200

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Sep

-200

6

Mar

-200

7

Ho

spit

al a

dm

issi

on

s

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100

200

300

400

500

600

700

800

Use

/po

sses

s ar

rest

s

Hospital admissions(amphetamines)

Use/possess arrests(amphetamines)

Methodological issues

• Narcotics use/possess as a proxy for heroin?

• Are use/possess arrests a good indicator for drug use?

• When did the heroin shortage start?

Table 2: Monthly use/possess arrest rates for emphatamines and narcotics, Janurary 1995 - September 2007

0

50

100

150

200

250

300

350

400

Jan-

95

Jul-9

5

Jan-

96

Jul-9

6

Jan-

97

Jul-9

7

Jan-

98

Jul-9

8

Jan-

99

Jul-9

9

Jan-

00

Jul-0

0

Jan-

01

Jul-0

1

Jan-

02

Jul-0

2

Jan-

03

Jul-0

3

Jan-

04

Jul-0

4

Jan-

05

Jul-0

5

Jan-

06

Jul-0

6

Jan-

07

Jul-0

7

Use/possess narcotics

Use/possess amphetamines

Amphetamines and narcotics use/possess

Correlations, use/possess amphetamines and narcotics

0

50

100

150

200

250

300

350

400

1995

/Jan

1995

/Jun

1995

/Nov

1996

/Apr

1996

/Sep

1997

/Feb

1997

/Jul

1997

/Dec

1998

/May

1998

/Oct

1999

/Mar

1999

/Aug

2000

/Jan

2000

/Jun

2000

/Nov

2001

/Apr

2001

/Sep

2002

/Feb

2002

/Jul

2002

/Dec

2003

/May

2003

/Oct

2004

/Mar

2004

/Aug

2005

/Jan

2005

/Jun

2005

/Nov

2006

/Apr

2006

/Sep

2007

/Feb

2007

/Jul

2007

/Dec

Possession and/oruse of narcoticsPossession and/oruse of amphetamines

r = -0.39

r = 0.80

r= -0.58

r = -0.38

r = -0.38

Correlations

Methodological issues

• Narcotics use/possess as a proxy for heroin?

• Are use/possess arrests a good indicator for drug use?

• When did the heroin shortage start?

• Is narcotics use centred around different locations than ATS use?

Map of narcotics arrests

Map of amphetamine arrests

Types of analysis• Vector autoregression

– Whole of NSW

– High use LGAs: Sydney, Marrickville, Bankstown, Liverpool, Fairfield, Wollongong, Newcastle

• ARIMA regression– Entire time period (Jan 1995 – Sept 2007)

– After first drop (Mar 1999 – Sept 2007)

– After onset of ‘heroin shortage’ (Dec 2000 – Sept 2007)

– Period of heroin drop (Mar 1999 – Apr 2002)

VAR Results – High use LGAs 

Lag Coefficient (with standard error) p-val Coefficient (with standard error) p-val1 0.012 (0.091) 0.894 -0.033 (0.076) 0.6642 -0.012 (0.108) 0.914 -0.006 (0.080) 0.9413 -0.154 (0.112) 0.168 -0.086 (0.078) 0.2704 -0.010 (0.109) 0.358 0.088 (0.079) 0.2615 0.098 (0.092) 0.289 0.056 (0.075) 0.456

Narcotics model Amphetamines model

VAR Results – NSW Lag Coefficient (with standard error) p-val Coefficient (with standard error) p-val1 -0.076 (0.090) 0.398 -0.092 (0.076) 0.2232 0.017 (0.107) 0.870 0.029 (0.080) 0.7143 -0.244 (0.107) 0.023 0.005 (0.077) 0.9494 -0.097 (0.109) 0.377 -0.075 (0.077) 0.3325 0.199 (0.094) 0.035 0.028 (0.072) 0.694

R-squared = 0.348

Narcotics model Amphetamines model

R-squared = 0.268

Results - ARIMAModel 1

Jan 1995 - Sep 2007Model 2

Mar 1999 - Sep 2007Narcotics 0.079 (0.090) 0.055 (0.105)Constant -0.368 (1.354) -2.470 (1.705)AR(1) -0.367 (0.055)* -0.384 (0.061)*AR(3) -0.136 (0.069)* -0.158 (0.080)*

Model 3 Dec 2000 - Sep 2007

Model 4 Dec 2000 - Apr 2002

Narcotics 0.020 (0.086) 0.105 (0.264)Constant -1.793 (1.833) -6.366 (4.601)AR(1) -0.264 (0.106)* -0.366 (0.149)*AR(3) - -

Summary and discussion

• No evidence of drug substitution was found

• Although ATS use increased after the ‘shortage’, this is part of a long term increasing trend

Amphetamines use/possess, 1995 – 2007

y = 1.0394x + 57.049R2 = 0.7579

0

50

100

150

200

250

300

350

Jan95

Jul95

Jan96

Jul96

Jan97

Jul97

Jan98

Jul98

Jan99

Jul99

Jan00

Jul00

Jan01

Jul01

Jan02

Jul02

Jan03

Jul03

Jan04

Jul04

Jan05

Jul05

Jan06

Jul06

Jan07

Jul07

Possession and/or use of amphetamines, NSW Linear (Possession and/or use of amphetamines, NSW)

Reported incidents

Summary and discussion

• No evidence of drug substitution was found• Although ATS use increased after the

‘shortage’, this is part of a long term increasing trend

• Rather than focusing on heroin and supply reduction policies, need to focus on ATS use and how this can be reduced

• Note that these results hold for NSW only