Changes in the frequency of use and abuse of drugs by Los Angeles County methadone maintenance patients: an observation based on urine drug testings in 1975 and 1979

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ABSTRACT
Introduction
Method
Results and discussion

Details

Author: R. D. BUDD
Pages: 27 to 30
Creation Date: 1981/01/01

Changes in the frequency of use and abuse of drugs by Los Angeles County methadone maintenance patients: an observation based on urine drug testings in 1975 and 1979

R. D. BUDD
Los Angeles County Coroner's Office. Los Angeles. California. United States of America

ABSTRACT

A survey has been made of the drugs found in the analysis of 10,000 urine specimens collected from Los Angeles County methadone maintenance patients during the summer of 1979. The results of this survey have been compared with the results of a survey carried out in the same County in 1975, indicating a marked decrease in use of drugs monitored in urine specimens. Some methodological limitations of data used in this study have also been discussed.

Introduction

There has been considerable controversy about the effectiveness of maintenance programmes. It is therefore important to determine whether they actually have been able to reduce abuse of opiates, especially heroin, in a given population.

In 1975 the laboratory of the Rancho Los Amigos Hospital began testing urine samples for drugs from methadone maintenance patients in Los Angeles County.

In the autumn of the same year a survey of the extent of drug use within the methadone maintenance population was carried out [ 1] . Four years later a second survey was carried out. Comparison of the two surveys provides one means of assessing the effectiveness of the methadone maintenance programmes.

Method

The population studied consisted of persons enrolled in Los Angeles County methadone maintenance programmes.

Some patients were enrolled in compliance with legal or probationary conditions, but most of the patients were there voluntarily. Patients could be terminated from the programme for violation of methadone regulations, such as continued drug abuse.

Collection of urine samples

Urine samples were collected at the individual methadone clinics under the supervision of clinic personnel. By state law, all persons enrolled are required to be tested at least weekly on a random time, short-notice basis, for methadone and morphine, and monthly for barbiturates and amphetamines. In practice, all patients were tested weekly for all drugs.

The urine samples were kept under refrigeration from the time of collection through analysis except while being transported to the laboratory. Results of the analyses were reported back to the clinics within 96 hours of the time of specimen collection.

Sample analysis

All urine samples were screened for the presence of opiates and barbiturates by radioimmunoassay [ 2] [ 3] and for the presence of methadone and amphetamines by Enzyme Multiplied Immunoassay Technique (EMIT) [ 4] [ 5] . All samples found positive for opiates, barbiturates and amphetamines, or negative for methadone, were confirmed by both gas chromatography and thin layer chromatography [ 2] [ 3] [ 5] [ 6] [ 7] . In the analysis strict quality control procedures were employed.

Results and discussion

Ten thousand urine samples were collected in May, June and July 1979 from the Los Angeles County methadone maintenance population and tested for the presence of opiates (codeine and morphine), barbiturates (allylbarbital, amobarbital, butabarbital, pentobarbital, phenobarbital and secobarbital), amphetamines (amphetamine and methamphetamine), methadone and, when necessary, the primary metabolite of methadone.

The results of this 1979 survey and the earlier 1975 survey [ 1] are summarized in tables 1 and 2. The results of the 1975 survey have been extrapolated to 10,000 samples.

The results indicate that while there has been little change in methadone usage, there has been a substantial decrease in the use of other drugs after four years. The percentage of drugs other than methadone identified in urine dropped from 23.0 per cent to 13.4 per cent (table 1) and the total number of drugs found dropped by more than one half (table 2). All of the drugs, other than methadone, were found less frequently than they were in 1975 (see table 2).

Table 1

Results of testing of 10,000 urine samples for methadone and other drugs

 

Number of samples

 

Result of analysis

1975

1979

Methadone
     
 
Positive for methadone
9633 9666
 
Positive for methadone metabolite only (negative for methadone)
141 219
 
Negative for methadone and its metabolite
226 115
Drugs other than methadone
     
 
Positive for drugs other than methadone
3362 1561
 
Positive for opiates
2487 1122
 
Positive for barbiturates
550 296
 
Positive for amphetamines
325 143

Table 2

Results of testing of 10,000 urine samples for drugs other than methadone

 

Number of samples

 

Drug

1975

1979

Percentage decrease

Morphine
1715 776 54.8
Codeine
772 346 55.2
Phenobarbital
354 210 40.7
Amphetamine
228 108 52.6
Methamphetamine
97 35 63.9
Amobarbital
44 29 34.1
secobarbital
74 25 66.2
Allylbarbital
19 16 15.8
Pentobarbital
34 13 61.8
Butabarbital
25 3 88.0
Total
3362 1561 53.6

The results also indicate that there has been no significant change in the preferred drugs of abuse (see tables 1 and 2). The opiates (codeine and morphine) are still by far the most frequently found drugs.

The results would appear to indicate that Los Angeles County methadone maintenance programmes have achieved some success in reducing use of drugs other than methadone among their populations. However, several factors must be considered in interpreting these results and their significance.

First, a sample in this study does not represent a person. The 1979 survey, for example, includes about 13 samples from each person in the methadon maintenance programmes. The samples were collected in a similar manner in 1975.

Secondly, metabolism may have affected the results of the surveys. Some of the morphine positives may be due to heroin or codeine metabolism; very few were probably actually due to morphine use itself. Some of the amphetamine positives may be due to methamphetamine metabolism. However, although many of the morphine and amphetamine positives may be due to metabolism of other drugs, this factor was probably present in the studies of both years.

Some of the drugs used were obtained on prescription. In a survey based on urine testing it was not possible to separate prescription use from non-prescription use. There is no reason, though, to suspect that prescription drug use would differ substantially over the four years.

While the results indicate a substantial decrease in drug use of tested drugs other than methadone over the four years, they may also indicate a switch from the drugs that are detected by our laboratory to drugs for which we do not test.

We do not have the information to substantiate or refute this notion. We also have no way to compare the frequency of use of other drugs in the two periods studied.

Finally, since methadone maintenance patients who continue to abuse drugs can be removed from the programme, the decrease in drug use found in the 1979 survey may indicate only a weeding out from the programme of persons who continue to abuse drugs.

References

001

N. C. Jain and others. "Patterns of drug use among methadone maintenance patients in Los Angeles County", Bulletin on Narcotics . vol. 29, No. 2 (1977), pp. 45-53.

002

N. C. Jain and others, "Mass screening and confirmation of codeine and morphine in urine by radioimmunoassay-GLC", Journal of Pharmaceutical Sciences. vol. 66, 1977, pp. 66-69.

003

N. C. Jain and others, "Mass screening and confirmation of barbiturates in urine by RIA/gas chromatograph", Clinical Toxicology . vol. 2, 1976, pp. 221-233.

004

EMIT Methadone Assay, Enzyme Immunoassay for rapid analysis of methadone in urine, Syva Corp., Palo Alto. California.

005

N. C. Jain and others, "Mass screening and confirmation of seven sympathomimetic amine drugs by EMIT-gas chromatograph", Journal of Analytical Toxicology . vol. 1. 1977. pp. 233-235.

006

R. D. Budd, D. F. Mathis and W. J. Leung, "Screening and confirmation of opiates by thin layer chromatography", Clinical Toxicology . vol. 16, No. 1 (1980), pp. 61-66.

007

R. D. Budd and W. J. Leung, "TLC confirmation of methadone and its- primary metabolite in urin". Clinical Toxicology. vol. 16, No. 1 (1980), pp. 55-59.