Smoking cessation with behaviour therapy or acupuncture—A controlled study

Res. The-. Vol. 21, No. 4, pp. 417424, 1983 Printedin Great Britain

00057967/83$3.00+ 0.00

Behm.

Pergamon Press Ltd

SMOKING CESSATION WITH BEHAVIOUR THERAPY OR ACUPUNCTURE-A CONTROLLED STUDY JEAN A. COTTRAUX,‘* RAOUL HARF,2-4 JEAN-PIERREBOISSEL,~JACQUESSCHBATH,~ MARTINE BOUVARD’ and JO~~LLE GILLET~ ‘Medical Psychology Dept, Hapital Neurologique, 59 boulevard Pinel, 69003 Lyon: ‘Clinical

*Pneumology Dept, HBpital Ste Eugtnie, Lyon; Pharmacology Unit, HBpital Neurocardiologique, aispensaires antituberculeux, Lyon, France

Lyon;

and

(Received 3 December 1982)

Summary-Five hundred and fifty-eightcigarettesmokers (mean 31 cigarettes/day)were randomizedin four groups: Acupuncture, Behaviour Therapy, Placebo Medication and Waiting-list Control. The life-table analysis of smoking cessation showed, at a 12-month follow-up, no difference between Acupuncture, Behaviour Therapy and Placebo. Differences appeared only in an analysis of the abstinent subjects at each data point. Behaviour Therapy and Acupuncture accounted for significantly more abstinent subjects than Placebo at the end of the 2-week therapeutic phase. However at 9 and 12 months Acupuncture had a statistically-significant greater number of abstinent subjects than Behaviour Therapy, but there was no difference between Acupuncture and Placebo. The percentage decrease in smoking from baseline appeared significantly greater at 12 months in the first three groups than in the Control conditions. However, as in most smoking-cessation studies, the overall effect was small and non-specific. The results reflect the importance of maintenance programmes and of the prevention of addiction.

INTRODUCTION

Behavioural medicine and behaviour-therapy techniques have been applied to smoking cessation many times. However, no studies have shown a significant durable effect (Hunt and Bespalec, 1974; McFall and Hammen, 1971). More recently, the rapid-smoking technique has produced some encouraging outcomes, but its effectiveness and safety have been disputed (Lichtenstein and Danaher, 1976). To date, there is no convincing evidence that the rapid-smoking technique is either effective or safer (Lichenstein and Danaher, 1976). Acupuncture has been studied more recently, but the durability of its effects may also be questioned (Lagrue, Poupy, Grillot and Ansquer, 1980; Lamontagne, Annable and Gagnon, 1980). The aim of the present study was to compare the effectiveness of two inexpensive, harmless and quick techniques to help smoking cessation in a large population. The two techniques compared were Poupy’s (1977) method of needle acupuncture and behavioural group therapy involving stress-reduction and self-control techniques. Although the predictive value of personality factors and the relationship of psychosocial factors to treatment outcomes were also measured, the present report deals only with the question of effectiveness. MATERIALS

AND

METHODS

Subjects Volunteers were recruited by an 8-day advertisement campaign on TV and radio and in Lyon’s three daily newspapers. A trial comparing behaviour therapy acupuncture and a new medication was announced. Each advertisement stated that the therapy was free of charge, but it was clearly expressed that the study requested a random allocation of Ss to the therapeutic procedures. Ss were required to be born in France, between 18 and 50 yr of age, and to have smoked more than 10 cigarettes/day for at least 2 yr. They also have to live in Lyon’s administrative area, and be accessible by phone. Only one member per family group was admitted. Ss who did not comply with the requirements of this study, demanded a specific technique or were tobacco store keepers, were excluded. The eligible Ss had to call one of 10 centres for a first screening. They were called *To whom

all correspondence

should

be addressed. 417

418

JEAN A. COTTKAUXet al.

back for a second screening and received an appointment for an evaluation session consisting of a demographic and medical-history questionnaire and a questionnaire evaluating the smoking rate. The total amount of cigarettes smoked since the beginning of the habit was calculated. An abbreviated version of the MMPI (minimult) was completed. A motivation questionnaire inspired by Mausner (1973) was administered. On the questionnaire the S rated from 0 to 10, 12 statements to determine whether the decision to enter the treatment derived from pressure by others, fear of illness or relatively free will. Before leaving the screening session, the volunteers had to sign a consent form which explained the experimental conditions, namely random allocation and follow-up contact during 1 yr. Out of the 1329 Ss who called, 317 were excluded because they did not meet the eligibility criteria and 448 called for entry after the completion of the four groups, 6 Ss refused to sign the consent form. Thus a total of 558 Ss participated in the study. Those calling after the study commenced, received a letter commending their desire to stop smoking and advising them to get in touch with another smoking-cessation clinic.

A fully-randomized between-group comparison design was used. A Placebo group and a no-intervention Waiting-list Control group were included to account for placebo effects and spontaneous changes in smoking, respectively. The sample was randomized in four groups: Behaviour Therapy (n = 138); Acupuncture (n = 140); Placebo Medication (n = 140); and Control (Waiting-list; n = 140). The only criterion for stratification was the presence or absence of one smoker in the home. Trea tnlen ts Behuviour Therapy. The treatment phase for all three experimental groups lasted 2 weeks. The Behaviour Therapy package was aimed at helping people to quit smoking and helping them to maintain their progress through stress reduction. To address these goals, group therapy was conducted in groups of 15 Ss with two therapists. Three weekly sessions were conducted and the length of each session was 3 hr. Ss discussed their habit, its reinforcing and aversive values, the difficulty of quitting and the positive effects of quitting. They were told that the programme was designed to reduce the stress of withdrawal. Ss were trained in Schultz’s relaxation procedure and individual GSR feedback was used to enhance relaxation. A systematic desensitization programme designed to reduce the stress of withdrawal was implemented. Under deep relaxation Ss had to imagine themselves in scenes which portrayed them as abstinent. Fifteen scenes were presented in which the length of imagined abstinence increased from 1 hr to 3 months. At the end of the first session, Ss were informed that the objective was to be abstinent at the end of the treatment phase, but that they could use progressive steps to reach this ultimate goal. Each was then allowed to decide his or her reduction level for the next week, and a contractual agreement was made with the group. Each day for 3 months Ss were required to record their smoking rate on self-evaluation sheets and then to mail it to the therapists. At the third and last session Ss received a relaxation and stress-desensitization audiotape to use every day for at least 3 months. Ss quitting during the therapeutic phase were strongly approved and taken as model for the other participants. Acupuncture. Acupuncture was made according to Poupy’s (I 977) recommendations. Three weekly sessions of 20 min each were made by an experienced acupuncturist. The needles were Shuai’ Gu pricked symmetrically for 20 min on the so-called ‘gall bladder’, ‘ lung’ (auriculotherapy), and Tong zi Liao points. Placebo. In the Placebo group, Ss received lactose capsules called “Medel 50” with an authoritative prescription warning them to avoid alcohol, and stating that an overdose would result in gastric side-effects. The prescription called for the pills to be taken 3 times a day, one pill before each meal. Each S met twice for 10 min with a doctor during the 2-week treatment period. The time spent by the therapists in contact with the Ss was balanced across the three groups. Control. In the Control group Ss were put on a l-year waiting-list and told they would have the choice of their treatment next year. The procedures used in this study were accepted by the INSERM ethics committee following the Helsinki Declaration (1975).

Smoking

cessation

with behaviour

therapy

or acupuncture

419

Follow -up At the end of the treatment period, Ss in Acupuncture, Behaviour Therapy and Placebo groups, completed a smoking-rate evaluation form and a minimult. Each patient of the three groups was contacted by mail or phone at 3-month intervals to assess smoking rate and the critical events occurring in his (her) life. The inquirer was blind to the treatment conditions of the Ss. A l-year follow-up session was organized to reassess smoking rate, weight, life events, personality factors (minimults) and opinions of the study. At that time Control Ss and unsuccessful Ss were free to choose the treatment they wished. In contrast with the Ss of the three experimental groups, Control Ss had no contact with the investigators prior to the 12-month reassessment. Stutistical

methods

One hundred patients were required to find a 10% difference with the Control group with an cxerror of 5%. All the Ss were maintained in their initial group throughout the study. A comparison of baseline data for the four groups was achieved through Chi-squared tests. The assessment of smoking behaviour required more complex statistical analysis. Some Ss stopped, resumed smoking and stopped again, some stopped convincingly and some decreased or increased their cigarette consumption. To represent those discrete phenomena we chose three methods of statistical analysis. (1) At each 3-month follow-up assessment the number of Ss who considered themselves abstinent at that point were compared. A Chi-squared analysis was used only if the smallest expected value exceeded 5 in each cell. In order to keep an overall confidence level of 0.05 nominal P values have been adjusted for multiple testing according to Tukey’s (1977) simple procedure. In addition pairwise comparisons between groups were made using Bonferoni-Goodman confidence intervals (Miller, 1966). Twenty-eight Ss (5% of the whole sample) were lost to follow-up at 12 months. They were counted as smokers at each data point but at 12 months several issues have been taken into account. They were counted as smokers, non-smokers and eventually as smokers or non-smokers according to the known ratio of successes and failures in each group. (2) A life-table analysis was carried out on relapse rate. According to the principles of life-table analysis all the Ss were considered as non-smokers at the beginning of the study the first relapse was counted as a definition failure. Log rank was calculated at 12 months for the relapse rate. (3) The rate of smoking reduction was also compared among the four S groups. To make this comparison, the percentage of smoking reduction from the pre-treatment assessment to the 12-month assessment was calculated for each S within the four groups for abstinent as well as non-abstinent Ss. Distribution was skewed. Logarithmic transform did not sufficiently modify the shape of the distribution to allow the use of an ANOVA method. Accordingly Chi-square was chosen for the statistical analysis. Then the Ss within each group were assigned, on the basis of smoking reduction, to fixed categories of percent change in smoking rate. Chi-squared analyses were performed to compare the four groups.

RESULTS

Compliance Only 130 Ss in Acupuncture, 119 in Behaviour Therapy and 125 in Placebo attended at least l-2 sessions. For the number of Ss who attended all 3 sessions their respective treatment were 110 in Acupuncture, 73 in Behaviour Therapy and 124 in Placebo therapy. Chi-squares comparing Ss who attended 3 sessions to those who attended O-2 sessions showed a statistically-significant difference (x2 = 48.18, df 2, P < 0.01). The fact that Behaviour Therapy had the lowest compliance rate suggests a relationship between low compliance and the complexity of therapy. Between-group

comparability

of the Ss characteristics

As represented in Table 1 the between-group comparability of baseline data was established for mean smoking rate, smoking duration, previous attempts to stop smoking, sex, age, educational level, contact with another smoker at home and at work, antecedent of depression, presence of an illness related to smoking as a risk factor (angina pectoris, myocardial infarction, intermittent claudication, chronic pulmonary disease, sinusitis, rhinitis). The four groups were balanced for

420

JEAN A. COTTRAUXet al. Table

1. Baseline

Acupuncture (?I = 140) Smoking rate/day (No. of cigs) Mean k SEM Duration of smoking habit (yr) Mean + SEM Previous attempt to stop smoking Never Once Several times Other smoker(s) at home Contact with another smoker at home Mean age Less than 2&30 30-40 40-50+ Sex Male Female Educational level School certif. and below General certif. of education; univ. degrees Others Antecedent of depression Illness related to smoking as risk factor Statistical

analysis

reveals

no differences

-

31.30 + 1.02 18.6 k 0.66

data Behaviour Therapy (n = 138) 31.46kO.97

Chi-squares

qf

abstinent

Control

31.55 + 1.07

30.97 f I.12

17.7 + 0.66

18.5 f 0.66

I5 63 62 52 I08

21 61 66 50 II5

I9 61 60 54 II2

33 60 47 53 II9

36 49 45

38 45 46

39 57 44

35 63 40

I08 32

I05 33

105 35

II8 22

94

93

77

96

38 8 27

36 9 28

52 II 31

37 7 22

I7

I8

22

the four groups

at P < 0.05.

these variables except for previous attempts to stop smoking group, but without reaching the 5% level of significance. Comparison

(n = 140)

18.00 + 0.66

22 between

Placebo (n = 140)

Ss in Acupuncture,

Behaviour

which were less frequent

Therapy

and Placebo

in the Control

at each data point

comparing

the three groups (Table 2) showed a significant difference at 15 days 12 months (P < 0.02). Pairwise comparisons showed that the number of abstinent Ss at 15 days was significantly greater in Behaviour Therapy or Acupuncture than in the Placebo group (P < 0.004). But at 9 and 12 months Acupuncture had a significantly greater number of abstinents than Behaviour Therapy (P < 0.004). However at 9 and 12 months (P < 0.02), 9 months

(P < 0.02) and

Table 2. Comparison

of Acupuncture, Behaviour Ss at each measurement Acupuncture

Treatment stage (months) _ _~~.~.~_~._!~!%!~(n~ 0.5

Post-treatment 3

6

9

I2

A = abstinent smokers).

Therapy point) Behaviour Therapy

and Placebo

(abstinent

Placebo (n = 140)

30(21X) I08 2

39 (28%) 91 8

14(100/;) 125 I

A NA LFU

22 (16%) 115

22(16X) I08 8 15(ll%) II4 9 10 (7%) 115

14(100/,) I25 I l3(9%) 126 I 15(11X) 124

IO (:$) 120° 8

19 (1:5’::.) I19 2

A NA LFU A NA LFU A NA LFU A NA LFU

21 (I&) 1I4 5 22 (16%) II2 6 23 (16%) I08 9 Ss; NA = non-abstinent

Ss; LFU = lost to follow-up

(counted

as

Smoking

cessation

with behaviour

Table 3. Evaluation

therapy

of the abstinent

A = abstinent; Non-abstinent,

Ss at 12 months Behaviour Therapy (n = 138)

Placebo (n = 140)

Control (n = 140)

108 23 (16%) 9

120 10 (7%) 8

119 19 (13.5%) 2

122 9 (6%) 9

117 23

128 10

121 19

131 9

108 32

120 18

119 21

122 18

115.42 24.58

127.38 10.62

120.72 19.28

130.38 9.62

Acupuncture (n = 140) NA vs A vs LFU Hypothesis I (All the drop-outs are smokers) NA A Hypoihesis II (All the drop-outs are non-smokers) NA A Hypothesis III (The percentage of abstinent and non-abstinent Ss in each group is attributed to the drop-outs) NA A

421

or acupuncture

NA = non-abstinent Ss; LFU = lost to follow-up (counted as smokers). P = 0.02; Hypothesis I, P = 0.02; Hypothesis II, P = NS; Hypothesis III, P = 0.01.

Acupuncture and Placebo, as well as Behaviour Therapy statistical difference.

and Placebo showed no significant

Abstinent Ss at 12 months Table 3 represents an analysis of abstinent Ss at the 1Zmonth follow-up, there is only a difference if the comparison is made with the Control group (P < 0.02). There is no difference if all the drop-outs are counted as non-smokers. If all the drop-outs are counted as smokers, or if the percentage of abstinent and non-abstinent Ss in each group is attributed to the drop-outs there still is a significant difference between the four groups. Pairwise comparisons performed according to Hypothesis I (all the drop-outs are smokers) showed a superiority of Acupuncture over Behaviour Therapy (P -=x0.002) and Control (P < 0.002) but no difference between Acupuncture and Placebo, Behaviour Therapy and Placebo, Behaviour Therapy and Control, Placebo and Control. Pair-wise comparisons performed according to Hypothesis III (the percentage of abstinent and non-abstinent Ss is attributed to the drop-outs) showed statistically-significant greater effect of Acupuncture compared to Behaviour Therapy and Control, and of Placebo over Control (P < 0.002). Other comparisons showed no difference. Life table analysis The rate of relapsed Ss were compared between Acupuncture, Behaviour Therapy and Placebo. The log rank test performed at 12 months revealed no significant differences between Acu-

05

I 3

I 6

I 9

I 12

Months

Fig. 1. Maintenance

of smoking cessation. All Ss are considered as non-smokers study. The first relapse is counted as a definitive failure.

at the beginning

of the

422

JEAN A. COTTKAUXet (II.

Table 4. Mean percentage Treatment Stage (months)

and SEM of smoking Behaviour Therapy

Acupuncture

49.3 28.1 25.5 26.0 25.6

* 3.5 k 3.5 +_ 3.1 k 3.6 + 3.7

Smokers

at each data

0.5 3 6 9 12

35.2 14.3 I I.8 Il.4 10.7

* f k k k

48.3 22.7 18.2 13.6 Il.7

puncture, Behaviour Therapy and Placebo smoking-cessation maintenance. Analysis

qf‘ smoking

43.4 25.3 25.2 21.8 23.6

(lost to follow-up

3.5 2.7 2.9 2.7 2.7

k * + + +

Control

excluded)

63.8 +_ 3.3 35.1+ 3.9 27.7 + 3.4 20.5 k 3.6 18.5 F4.1

point

(No. of cigs)

Placebo

All Ss (lost to follow-up 0.5 3 6 9 12

reduction

3.6 3.5 2.8 3.2 3.8

* 3.00 k 3. IO +_ 3. IO k 3.6 +_ 3.6

and abstinent 37.1 17.0 17.5 12.3 I 1.4

4.9 rfr 3.5 Ss excluded)

* 2.8 + 2.6 k 2.6 + 3.1 &-2.9

-2.12

(log rank = 2.65 NS). Figure

+ 2.8

1 represents

the curve of

reduction

The mean percentage and SEM of smoking reduction is shown in Table 4, for all the abstinent and non-abstinent Ss. Table 5 represents the distribution of percentage of smoking reduction in all the Ss and non-abstinent Ss. A Chi-squared analysis was performed on the follow-up data from all Ss in the four treatment groups. The analyses revealed a significant difference between the percentage of smoking reduction among the four groups (P = 0.003). Inspection of data suggests a superiority of Acupuncture, Behaviour Therapy and Placebo over the Control group. The same Chi-squared analysis carried out in non-abstinent Ss revealed a significant difference between Acupuncture, Behaviour Therapy, Placebo and the Control group (P = 0.03). The inspection of data suggests again a superiority of Behaviour Therapy, Acupuncture and Placebo over the no-treatment Control group. DISCUSSION Our study fails to demonstrate the effectiveness of one treatment over another, furthermore the treatment effects seem to be non-specific. In the long run, placebo seemed to be as effective as Table

5. Distribution

Smoking

of the percentage of smoking excluded)

reduction

Acupuncture

reduction

Behaviour Therapy

Ss lost to follow-up

Placebo

Control

n

All Ss at I2 months z < _907<, - 90”‘0 .i .\- < - 40’/I 0 -40” 0 < . .\’ < -20” 0 -2o”‘<.X

23 16 18 I7 39 I2 6

IO 20 28 14 42 4 I2

20 14 27 12 48 IO 7

9 4 19 I9 43 17 20

62 54 92 62 172 43 45

I5 27 12 48 10 7

4 I9 19 43 I7 20

55 92 62 172 43 45

xz = 45.34; (I/‘= 18; P = 0.0003.

- 99”,, < _I.< -4O’X, -40” .< I < -2OY -2O”,, + 30”,,
Non-abstinent ~~ at ~~ I2 months _~_ ~_ I6 20 18 28 I7 14 39 42 I2 4 6 12

15: P = 0.003.

Smoking

cessation

with behaviour

therapy

or acupuncture

423

behaviour therapy and acupuncture (in the way both treatments were used in our study) for smoking cessation. Initially, behaviour therapy and, to a lesser degree, acupuncture seem able to induce a significant behavioural change that is only temporary. To enable a comparison of these results with results of other studies it has been necessary to obtain three kinds of measurements: abstinence at given points, rate of relapse and percentage of reduction. According to classical surveys on smoking-cessation programmes, when non-specific procedures are used, only 20”/” of the abstinent subjects at the end of a smoking-cessation programme remain so 6 month later (Hunt and Bespalec, 1974). These effects are comparable to the combined results from previous studies which used specific procedures: a mean smoking cessation of 26% at the end of the treatment, and of 13% at 6 months are quite similar to these figures. However the rapid-smoking procedure has been credited with a 60% abstinence rate at 6 months (Lichtenstein and Danaher, 1976; Tongas, 1978). Since our aim was to develop a quick, painless and harmless technique the rapid-smoking procedure was not included in our study. Many subjects may be deterred from entering an aversive smoking-cessation programme and it may create a sample bias. Because only strongly-motivated subjects or those with peculiar personality features, might enter such a programme, we felt it was better to use more commonly-attractive techniques. Sample bias may explain the positive outcomes of rapid smoking with some researchers, and negative ones with some others. A recent study (Poole, Sanson-Fisher and Allengerman, 1981) on different modalities of rapid smoking found a 64% rate of smoking cessation at post-treatment, but at 6 months the cessation rate had dropped to 26% and at 12 months it had dropped to 21%. In light of our study’s objectives, a 5% increase in the success rate would not seem to justify taking the cardio-respiratory risks created by rapid smoking. Another study (Lamontagne et al., 1980) compared acupuncture for smoking withdrawal, acupuncture for relaxation and self-monitoring. This study found no difference between the three conditions and the figures are similar to ours at 6 months, as 20% of the subjects were abstinent when self-monitoring was used. Our study of reduction suggests as well that we obtained a non-specific effect because the three experimental groups did not differ significantly from each other after 12 months. Any kind of intervention is better than no intervention to reduce smoking rate but the most effective intervention remains unclear since the placebo effect seems as strong as the so-called specific effects. The conclusions seem to be consistent with all the surveys on smoking-cessation programmes (Lichtenstein and Danaher, 1976). Our behaviour-therapy programme may be criticized as being too rapid despite the maintenance procedures we used (relaxation and desensitization tape plus self-observation during 3 months). But with the population we had, a long-lasting therapy programme might have resulted in a lower rate of compliance which would have made it difficult to draw conclusions. From such data is raised the issue of selecting the subjects .according to their characteristics and matching them to appropriate treatments. Our forthcoming study on motivational and socio-demographic data may shed some light on this question. CONCLUSIONS As far as smoking cessation is concerned the overal effect of both acupuncture and behaviour therapy is small and non-specific, furthermore there is no clear difference between the methods evaluated. These results stress the potential importance of maintenance procedures to preserve the therapeutic effect. The results could be explained by the characteristics of our sample. which is less selected than in most studies on smoking cessation. Moreover our sample was made up of seemingly heavier smokers than in the general population. A further study of the MMPI and motivation scales may reveal a relationship between outcomes and subjects’ expectations or personality types and outcomes. This study does point out, however, that any intervention is better than waiting-list to ensure smoking reduction. But neither acupuncture, nor a behaviour-therapy package involving stress reduction and self-control, appears to be a powerful method for smoking cessation. Future research should stress the prevention of chemical dependency, through sociallearning programmes. It might be easier to never start than to quit. Acknowledgemenls-The authors wish to express their appreciation to F.I.L., FR3 Rhbne-Alpes, le Progres, le Dauphine Lib%, le Journal Rhone-Alpes, Evelyne Mallard, Christian Juenet, Lionel Collet, Marie-Jo&e Faucon, Henri Chambon. Serge Ferry, Jean Bourdeix and Margaret Salinger for their help. This work was supported by a grant from INSERM.

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JEAN A. COTTRAUX et al.

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