Summary
Introduction
Material and method
Results
PERSONAL HISTORY
Drug history
PATTERNS OF DRUG MISUSE
B. Clinical Groups
CHANGING PATTERNS OF DRUG MISUSE
Discussion
Acknowledgements
Bibliography
Author: R. GARDNER , P. H. CONNELL
Pages: 9 to 15
Creation Date: 1971/01/01
This paper reports the findings obtained from a questionnaire given to all opioid users attending a special drug dependence clinic between March 1968 and February 1969.
Demographic data include details of notification, area of referral and referring agent, nationality, age, sex and social class. Other data presented include marital status, employment, forensic history, medical history, psychiatric history, drug history and patterns of drug misuse. Clinical groupings by age are defined.
The changing patterns of drug misuse are noted, and discussion includes consideration of the comparison between the present population and earlier studies, morbidity, classification and recent developments.
The rising incidence of heroin misuse among young people led to the Second Interdepartmental Report (1965) which confirmed that the addict be treated under a medical rather than a criminal label. Its recommendations (except for compulsory admission of addicts) were implemented (Dangerous Drugs Act 1967). The setting up of the Clinic, the experience in which is the basis of this study, and the design of a questionnaire suitable for obtaining standard data at all treatment centres is described elsewhere (Connell and Gardner). This hospital holds special sessions to deal not only with opioid dependence, but also with other types of drug dependence.
* Drug Dependence Clinical Research and Treatment Unit.
One hundred and seven new cases of opioid users (50 % of total users attending the clinic) were seen between
March 1968-February 1969. The questionnaire was administered to 83%. The data on the remaining 17% was therefore not so comprehensive for patterns of drug misuse. Other sources of data included identification of patients by contacting the Home Office; hospital notes from elsewhere; Probation Officers' reports; other informants; further history from the patient; physical examination and analysis of urine for the presence of drugs.
DEMOGRAPHIC DATA
New Cases: The total numbers of patients seen in the year are shown in table 1. The greater proportion attended in the first three months of the clinic's opening. From October 1968 individuals previously misusing heroin appeared regularly with methadone as their main opioid of misuse, and this trend continued throughout 1969.
Notification: The majority, including all those referred to the Clinic by prescribing general practitioners and other treatment centres, were already known to the Home Office. Those with a shorter duration of opioid misuse and often obtaining opioid drugs solely from an illegal source, were significantly less likely to be known to the Home Office (table 5).
Month |
Heroin |
Methdone |
Other opioids * |
Total |
---|---|---|---|---|
March-May
|
52 | 2 | 2 | 56 |
June-August
|
12 | 0 | 2 | 14 |
September-November
|
13 | 2 | 2 | 17 |
December-February
|
14 | 6 | 0 | 20 |
TOTAL
|
91 | 10 | 6 | 107 |
* Morphine (2); Pethidine (2); Opium (1); Chlorodyne (1).
Area of Referral and Referring Agent: Only 37 % were living in South London, others from this area were possibly attending treatment centres which had opened earlier. The areas of South London from which these patients came were far too widespread to be regarded as being within the district of the Maudsley Hospital. Sources of referral are indicated in table 2.
No. of patients |
Percentage |
|
---|---|---|
Notification (Home Office)
|
||
Known
|
61 | 57.0 |
Not known
|
46 | 43.0 |
Area from which referred
|
||
S.E. London
|
22 | 20.6 |
S.W. London
|
18 | 16.8 |
Rest London
|
45 | 42.1 |
Outside London
|
22 | 20.6 |
Referring agency
|
||
Prescribing G.P.
|
30 | 28.0 |
Self
|
22 | 20.6 |
Other T.C. or Hospital
|
22 | 20.6 |
Social Agencies
|
20 | 18.7 |
G.P. (non-prescribing)
|
13 | 12.1 |
National origin
|
||
British
|
87 | 81.0 |
North American
|
16 | 15.0 |
Other
|
4 | 4.0 |
Age groups
|
||
14-19
|
27 | 25.2 |
20-24
|
35 | 32.7 |
25 +
|
45 | 42.1 |
Sex
|
||
Male
|
85 | 79.4 |
Female
|
22 | 20.6 |
Social class (father)
|
||
I + II
|
27 | 31.0 |
III
|
37 | 42.6 |
IV + V
|
23 | 26.4 |
Unclassified
|
20 |
-
|
Present marital status
|
||
Never married
|
72 | 68.6 |
Married/widowed
|
18 | 17.1 |
Separated/divorced
|
15 | 14.3 |
Not known
|
2 |
-
|
Present
|
||
Working, full-time
|
32 | 30.4 |
Working, part-time
|
7 | 6.7 |
Unemployed
|
66 | 62.9 |
Not known
|
2 |
-
|
Social class (patient)
|
||
I + II
|
17 | 18.7 |
III
|
27 | 29.7 |
IV + V
|
47 | 51.6 |
Unclassified
|
16 |
-
|
Nationality: Patients born in the United Kingdom represented 77 % of the total and four were born in the Republic of Ireland. All but four individuals in this series (two North Americans, one Indian and a West Indian) were Caucasians. There were eleven Canadians (all over the age of 29) who had lived in this country for a mean duration of 6.6 years, receiving heroin from medical practitioners legally. Patients of all "other" nationalities were older than 26 years.
Age: The mean age was 26.6 (SD±10.8) with a range of 14-79 years. Fifty-three (50 %) were aged between 16-22 and twenty-six were aged 30 or more. Two age groups were not statistically separate but scrutiny of the distribution suggested further analysis of groups below and above the age of 25. In the older age group, heroin users (present or past) aged 35 or more are over represented in this series in comparison with those known to the Home Office in 1968-15.6% as against 4.4% (X 2 = 20.4, one degree of freedom, p < 0.01).
Sex: The ratio of males : females is 4 : 1 and compares with the Home Office figures of 5 : 1. The sexes are similar with respect to age distribution and patterns of drug misuse. More women had been married (not statistically significant) and three were unmarried mothers.
Social Class: Patients coming from a background of social class I-II (Registrar General's Classification 1957) represented 31 % of this series. There was no significant correlation between age at first attendance and social class, nor between sex and social class.
Schooling: There was only one school boy in this series (table 3).
Marital Status: The older addicts were more likely to have been married and half their marriages had already ended in separation or divorce. Of the 16 who were married at first attendance (table 2) only four showed continuing stability.
Employment: Table 2 indicates the high proportion of unemployed at first attendance and that 51.6% had only achieved semi-skilled or unskilled work. Employment at first attendance was not correlated with age nor with duration of opioid misuse.
Forensic: Seventy-five (70%) had been found guilty of offences of which 38 % were unconnected with the Drug Acts. Nine individuals had been in either Borstal or prison as well as approved school. Only fourteen had no forensic record (table 3).
No. of patients |
Percentage |
|
---|---|---|
Schooling
|
||
Until age 16
|
83 | 77.6 |
After age 16
|
23 | 21.5 |
"O" Level
|
(15) | |
"A" Level
|
(7) | |
Further education
|
(11) | |
Not applicable
|
1 | 0.9 |
Forensic history
|
||
No offence
|
14 | 13.1 |
Not known
|
18 | 16.8 |
Court offences
|
75 | 70.1 |
Juvenile only
|
(11) | |
Adult only
|
(23) | |
Juvenile and adult
|
(41) | |
Approved School
|
(10) | |
Borstal
|
(11) | |
Prison
|
(30) | (28.0) |
Probationa
|
(18) | |
Medical history
|
||
Abscess
|
23 | (21.5) |
Jaundice
|
20 | (18.7) |
Overdose
|
9 | |
Pulmonary infection
|
4 | |
Septicaemia
|
4 | |
Endocarditis
|
1 | |
Hospital admission b
|
46 | (43.0) |
Psychiatric history
|
||
Child guidance clinic
|
13 | (14.0) |
School maladjusted boys
|
2 | |
Suicidal attempt/gesture
|
22 | (20.6) |
Hospital admission
|
4 |
a At first attendance.
b In connexion with drug taking.
Medical: Table 3 lists the reported complications of drug misuse. 43% had previously been admitted to hospital, ususally for drug withdrawal or some complication of drug misuse.
Psychiatric: A background of behaviour disorder and adolescent problems was not uncommon (table 3). Formal psychiatric illness was rare (three with a history of hospital admission for depression), but 21% had made some suicidal attempt-usually by overdose. The relevance of this in terms of psychiatric diagnosis is unclear but some suicidal attempts were related to depression following withdrawal of CNS stimulants. A number of patients described showed paranoid symptoms due to the direct psychotoxic effects of these drugs (cocaine or amphetamine)(Connell, 1958).
Onset of drug misuse: In this series the mean age of onset of drug misuse was 18.1 years (SD±6.8) with a range of 13-59 years, all but five individuals having started before the age of 25. The two largest groups first misused amphetamine and cannabis respectively (table 4). Excluding non-British cases, they differed with respect to social class; significantly more of those starting on cannabis came from a social class I-II background (x2 = 4.09, one degree of freedom, p < 0.05). First misuse of the amphetamine-barbiturate pill (table 4) was associated solely with the younger age group, whereas all but two of those who had started directly on an opioid or progressed to one from alcohol, were in the older age group.
No. of patients |
Percentage |
|
---|---|---|
First drug misused
|
||
Amphetamine
|
38 | 38.8 |
A-B pill
|
21 | |
Amphet. Tab .
|
14 | |
Meth. amp.
|
3 | |
Cannabis
|
33 | 33.7 |
Opioid
|
15 | 15.3 |
Alcohol
|
10 | 10.2 |
Amyl Nitrite, L.S.D
|
2 | 2.0 |
Not known
|
9 |
-
|
Age first used opioid
|
||
14-19
|
58 | 57.4 |
20-24
|
24 | 23.8 |
25-29
|
13 | 12.9 |
30+
|
6 | 5.9 |
Not known
|
6 |
-
|
Opioid first misused
|
||
Heroin
|
93 | 87.7 |
Morphine
|
5 | 4.7 |
Pethidine
|
3 | 2.8 |
Opium
|
3 | 2.8 |
Methadone and Chlorodyne
|
2 | 1.9 |
Not known
|
1 |
-
|
Duration of progression to daily misuse (years)
|
||
0-1
|
59 | 56.7 |
1-2
|
13 | 12.5 |
2-3
|
11 | 10.6 |
3-6
|
8 | 7.7 |
Not applicable
|
13 | 12.5 |
Not known
|
3 |
-
|
Duration of opioid misuse (years)
|
||
0-1
|
26 | 25.7 |
1-2
|
19 | 18.8 |
2-5
|
23 | 22.8 |
5-10
|
15 | 14.9 |
10+
|
18 | 17.8 |
Not known
|
6 |
-
|
Main drugs misused i/v
|
||
Heroin
|
89 | (84.0) |
Methamphetamine
|
64 | (62.0) |
Cocaine
|
41 | (44.0) |
Methadone
|
23 | (24.0) |
Barbiturate
|
8 | (9.0) |
Source of opioid at first attendance
|
||
Illegal
|
62 | 58.0 |
General Practitioner
|
30 | 28.0 |
Treatment Centre
|
15 | 14.0 |
Age first misused opioid: The mean age of onset of opioid misuse was 21.2 years (SD± 6.8). More than one-half had started before the age of 20 (including 24 % of the older age group) and 81.2% had misused opioids before the age of 25 (see table 4).
First opioid misused: Fifty-nine (94%) of the younger age group had started on heroin whereas only thirty-five (78%) of the older age group had done so (table 4).
Duration of progression to daily misuse: Daily misuse took one year or more to achieve in thirty-two cases (31%) (table 4), the under twenties progressing more rapidly. Fear that heroin would not be prescribed may have lead to false claims of daily use in some cases, but thirteen individuals did give a history of sporadic (less than daily) use ("NA" in table 4).
Duration of opioid misuse: The mean duration of opioid misuse was 5.6 years with a range of 3 months-31 years. Duration was significantly correlated with age, patterns of drug misuse and source of opioid at the time of first attendance (table 5). Of those who had misused opioids for less than one year, 50 % were teenagers.
r |
p |
|
---|---|---|
Source of opioid
a (solely illegal/from G.P.)
|
0.500 |
.001
|
Home Office
b (not known/known)
|
0.446 |
.003
|
Other opioid (ever/never)
|
0.422 |
.011
|
A.B. pill
c (present/past/never)
|
0.484 |
.001
|
Amphetamine (ever/never)
|
0.464 |
.002
|
Methamphetamine i/v (ever/never)
|
0.458 |
.003
|
a This factor correlates significantly with Home Office (not known/known), r = 0.421; p <.005.
b Duration of opioid misuse in this instance was sub-divided into 1 year, 1-2, 3-9 and 10 +.
c Amphetamine barbiturate.
A. The clinic
Tables 4 and 6 indicate the presenting patterns of drug misuse, the mode of administration and the source of opioid at first attendance.
"Present" drug misuse: During the month before first attendance at the Clinic heroin had been the most widely misused opioid followed by methadone (table 6). Thirty-eight patients (26%) were misusing both these opioids, sixteen of them daily. Seven used methadone daily. Opioids other than methadone were rarely used with heroin. Combinations of heroin and methadone with one or more CNS stimulant drug were common, methamphetamine being injected by fifty-two (49%) of this series. Current misuse of amphetamine-barbiturate tablets with opioid drugs was unusual (see table 6) and probably explained by temporal progression from amphetamine to opioid misuse, e.g. in five instances there was a negative urinalysis for opioids at first attendance.
"Past" drug misuse: Only the opium and chlorodyne addicts and two addicts who were doctors taking morphine and pethidine respectively, had never misused heroin. All but ten had misused either cocaine or methamphetamine by injection. "Mandrax" (methaqualone and diphenhydramine) had been favoured by 79 % of those who had misused a non-barbiturate hypnotic (table 6). Table 4 indicates the drugs commonly injected intravenously.
The most typical of the older age group were among the over thirties and of the younger group, the teenagers. Table 7 indicates the main factors significantly correlated with age.
The older age group (25 years +): This included all "other nationalities" the two "therapeutic" addicts and the three with professional access to drugs. Those administering drugs by the oral route (four cases), with a duration of opioid misuse exceeding four years and all who had used another opioid than heroin or methadone, were in this group. Addicts currently misusing cocaine daily (table 6) had a mean age of 32.6 years and a mean duration of opioid misuse of 12.4 years. They often combined this drug with a CNS depressant-a non-barbiturate hypnotic in six instances and a barbiturate in two. Three older addicts were currently receiving prescriptions of barbiturates exceeding 800 mg. daily. This group included everyone who had either first misused alcohol or started directly on an opioid. Only 26 % had used the amphetamine-barbiturate pill (table 7). The Canadians were the most homogenous group amongst the older addicts. They came from a social class III-V background, their onset of drug misuse was illicit, all but one had misused cannabis and they had injected heroin intravenously. All denied misusing LSD type drugs. After several prison sentences in Canada they had come to this country to avoid further imprisonment. A striking feature was the ease with which they had obtained prescriptions for heroin on arrival in far larger doses than they had previously misused, some of them having left Canada within days of release from prison. All showed some ability to hold down a job even if this was generally an unskilled one. In contrast were the older British addicts with a predominantly social class I-II background, three having a private income. Eight of these had not worked for many years.
Present use * |
Past use |
||||
---|---|---|---|---|---|
Drug |
Daily |
Less than daily |
Ever/not now |
Never |
Not known |
Heroin
|
|||||
Number
|
73 | 22 | 7 | 4 | 1 |
Percentage
|
68.9 | 20.7 | 6.6 | 3.8 | |
Methadone
|
|||||
Number
|
23 | 31 | 21 | 22 | 10 |
Percentage
|
23.7 | 32 | 21.6 | 22.7 | |
Other opioid
|
|||||
Number
|
6 | 5 | 30 | 53 | 13 |
Percentage
|
6.4 | 5.3 | 31.9 | 56.4 | |
Cocaine
|
|||||
Number
|
12 | 8 | 31 | 42 | 14 |
Percentage
|
12.9 | 8.6 | 33.3 | 45.2 | |
Barbiturates
|
|||||
Number
|
6 | 7 | 22 | 54 | 18 |
Percentage
|
6.7 | 7.9 | 24.7 | 60.7 | |
Non-barbiturate hypnotic
|
|||||
Number
|
10 | 11 | 16 | 57 | 13 |
Percentage
|
10.6 | 11.7 | 17 | 60.6 | |
Amphetamine
|
|||||
Number
|
44 | 11 | 29 | 19 | 4 |
Percentage
|
42.7 | 10.7 | 28.2 | 18.4 | |
Amphetamine barbiturates pill
|
|||||
Number
|
0 | 11 | 48 | 39 | 9 |
Percentage
|
0 | 11.2 | 49 | 39.8 | |
Hallucinogens
|
|||||
Number
|
0 | 4 | 30 | 55 | 18 |
Percentage
|
0 | 4.5 | 33.7 | 61.8 | |
Cannabis
|
|||||
Number
|
3 | 25 | 50 | 17 | 12 |
Percentage
|
3.2 | 26.3 | 52.6 | 17.9 |
* Within one month of first attendance.
r |
p |
|
---|---|---|
Duration opioid (years)
|
0.793 |
.0001
|
Source opioid (solely illegal from G.P.)
|
0.427 |
.005
|
Other opioid (present/past/never)
|
0.444 |
.006
|
A.B.
* pill (present/past/never)
|
0.468 |
.002
|
Amphetamine (ever/never)
|
0.419 |
.007
|
Methamphetamine i/v (ever/never)
|
0.510 |
.001
|
* A.B. = Amphetamine barbiturate.
The Younger Age Group: These were all British and approximated to the young "non-therapeutic" addict whose increasing numbers evoked the Second Brain Report. Their onset of drug taking often followed the socio-cultural pattern of weekend amphetamine misuse, commonly of the amphetamine-barbiturate pill (Connell
1965) and progressing later to other drugs, often including methamphetamine by injection (table 7). Alternatively, they had first misused cannabis and progressed to other drugs. All had started their opioid misuse with heroin by injection, although a proportion later misused methadone as well.
Methadone: This drug was found to have been increasingly misused throughout the year. Of those who had never misused methadone at first attendance (table 6) seven later did so illegally. Comparison of six monthly periods (table 8) indicates that less new cases had" never" misused methadone and more were currently misusing it after September although both factors just failed to reach statistical significance. Reasons for misusing this drug included (i) the prescription of 10 mg. ampoules of methadone rather than 10 mg. tablets of heroin by some treatment centres as in all the referrals from other centres to this clinic: (ii) methadone was claimed to be more easily available than heroin from illegal sources (though derived from National Health Service supplies) by the end of 1968: (iii) it was not on the restricted list and was obtained from general practitioners either when the individual wished to readdict himself or to supplement a prescription from a treatment centre; and (iv) in the belief that it was easier to "get off" methadone than heroin.
Number of Patients |
|||
---|---|---|---|
History |
March-August |
September-February |
Total |
Never
|
18 | 4 | 22 |
Ever
|
42 | 33 | 75 |
Present
*
|
26 | 28 | 54 |
Past
|
16 | 5 | 21 |
* Within one month of first attendance.
Methamphetamines: From November 1968 no new cases presented on this drug ampoules of which had been withdrawn from retail sale by pharmacists in October 1968.
Barbiturates: At first attendance six of the eight cases who had misused barbiturates intravenously were North Americans. Later in the year six others (British) started misusing these drugs intravenously, the presence of barbiturates being confirmed by urinalysis. Between March and May 1969 six new cases treated claimed intravenous usage, and barbiturate was detected in the urine of five of them.
This series differs from the population known to the Home Office (Spear, 1969) and hence to most treatment centres in that the over thirty-fives and the North Americans are over represented. It confirms previous studies (Bewley, Kosviner et al., 1968; Willis, 1969) that British cases are not limited to the socially underprivileged section of the community, the coloured population is not prominent, and a high proportion of drug users are unemployed and in semi-skilled or unskilled work (Bewley, 1968; Hewetson and Ollendorff, 1964; Hicks, 1969; Willis, 1969).
The proportion with a forensic record unrelated to the Drugs Acts and often preceding the onset of drug misuse, is also in accord with the findings of others (Bewley, 1968; Willis, 1969; James, 1969) confirming that this problem cannot be regarded solely under a medical label. Morbidity was somewhat less than that reported by Bewley and Ben Arie (1968), whose subjects were hospitalized addicts. There was little evidence of formal psychiatric illness although central nervous stimulants produced psychotoxic effects in many of the cases, particularly those who had misused such drugs by injection. This finding is confirmed by that of Bewley (1968) but it is in contradistinction to the findings of Willis (1969) who did not note psychosis in any patient. However, Willis did not publish data on drug misuse and it may be that his population was not involved in amphetamine or cocaine use to the extent likely to produce psychosis or admission to hospital. Nor does he publish data on psychotic episodes prior to admission which many of our patients described. The data on previous psychiatric history (table 3) in this series suggest not only developing personality disorders in some patients, but also depressive reactions.
Classification of addicts remains difficult and there is an overlap between various categories. Mode of onset, although valuable in the epidemiological field, is less helpful in the clinical setting. For instance, the concept of "therapeutic" and "non-therapeutic" groups is not helpful in this study since ( a) there are only two "therapeutic" addicts, and ( b) one of them (British) probably had more in common clinically with the Canadians than with the other "therapeutic" addict, or the British teenagers. Nor is it likely that other treatment centres will find such a concept helpful. Operational definitions to obtain treatment populations such as have been employed by Dole et al. (1966) are important if there is to be any valid comparison of diagnostic and treatment methods from various centres. Simple data on age and duration of drug misuse (with some objective evidence of the latter) might well provide a framework to which more detail could be added, e.g. type of drug, modes of onset and administration, dosage, intermittent or daily use etc. and around which meaningful categorization or diagnostic groupings could be proposed. Such an approach is described elsewhere (Gardner and Connell).
The increasing misuse of methadone, including its use in ampoule form (Bewley, 1968; Spear, 1969; Connell, 1970) was confirmed in this series. It is clear that methadone is replacing heroin, thus undermining the rationale of restricting the prescription of heroin to licensed doctors (Bewley, 1968; Connell, 1969) and multiplying the sources from which legal opioid drugs may be obtained and misused. It has yet to be demonstrated that methadone is any less addictive than heroin or that its use by injection prevents any of the serious complications found in heroin addicts. Indeed Isbell et al. (1948) considered that its abuse potential was as serious as that of morphine and predicted (Isbell, 1948) that addicts would freely misuse methadone if it were available. 1 Stricter control of this drug and/or upon doctors prescribing it would seem to be indicated.
The increase in the numbers of individuals misusing barbiturates intravenously is also a growing problem which was noted in this series and confirmed by a recent study (Mitcheson et al., 1970). A questionnaire designed for use at treatment centres (Connell and Gardner) would
1. In the United Kingdom death of opioid users from the self-administration of methadone has increased (Gardner, 1970a), the linctus preparation presenting special hazards (Gardner, 1970b).
appear to be a simple, quick and effective way of noting differences in prescribing patterns or changing fashions in drugs misused by addicts.
Our thanks are due to Miss B. Kingsley B.Sc. of the Biometrics Unit, Institute of Psychiatry for statistical help and programming for analysis by the London University Atlas computer; and to Mrs. J. Barette and Miss L. Stamp for assistance in data collection.
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