Results

DEMOGRAPHIC AND SMOKING HISTORY DATA

The total number of pharmacies generating participants was 149 of a total of 1108 contacted (13.5%). The total number of questionnaires returned was 805.

Table 1 presents demographic and smoking history characteristics of the participants. Men and women were almost equally represented. The average age of respondents was 41 years (median 39 years), ranging from 18 to 87 years. Sixteen years is the minimum age to purchase cigarettes in New Zealand. The average duration of smoking was 19.7 years (median 18 years), ranging from two months to 67 years. Cigarette consumption was the main method of smoking (98% of respondents) with fewer than 2% reporting consumption of cigars or pipes as the main method. The average number of cigarettes smoked per day was 21.6 (median 20); the smallest number was two per day while one smoker consumed 75 per day.

PREVIOUS QUIT ATTEMPTS

Previous attempts to quit smoking had been made by 634 out of 805 (78.8%) total respondents, with men and women almost equally represented. Of the 634 purchasers who had made previous attempts to quit smoking, 325 (51.3%) reported the use of one or more nicotine-containing or other pharmaceutical products. This represents 40.4% of the total purchasers who completed the questionnaire. Analysis of the relationship between the use of nicotine-containing products, gender, and each of the number of years smoking, the number of cigarettes each day, and the age of the purchasers yielded no significant differences between the relevant subgroups.

Table 2 shows the products reported by the 325 respondents who had used one or more products in their previous quit attempts. The main products used were Nicotinell TTS, used by 195 purchasers, or Nicorette gum,28 used by 148 purchasers. Some respondents reported the use of more than one product previously. At the time of the study Nicotinell TTS had been available for purchase through pharmacy in New Zealand for about 18 months, while Nicorette gum had been available for nearly 10 years. The products Nicabate29 [a transdermal nicotine product—Marion Merrell Dow (known as Nicoderm in the United States)] and Nicobrevin (a non-nicotine product) were just starting to be heavily advertised during the period of the study.

PREVIOUS QUIT ATTEMPTS USING TRANSDERMAL NICOTINE

As detailed above, the number of previous attempts to quit smoking using a treatment course of Nicotinell TTS was reported by 195 out of 805 (24.2%) total respondents. One previous attempt using Nicotinell TTS had been made by 170 of this group, two attempts by 23, three attempts by two, and six attempts by one individual. For the first attempt the mean duration of use for each patch strength was similar and varied from 2.4 to 2.8 weeks. The maximum duration of use of any one patch strength was eight weeks. The mean total duration of patch use involving all strengths for the first attempt was 4.4 weeks, with a minimum of one week, a maximum of 13 weeks, and a median of three weeks.

For second attempts, the mean duration of use for each patch strength varied from 2.5 to 3.1 weeks. The mean total duration of patch use for all strengths for the second attempt was 4.3 weeks, with a minimum of one week, a maximum of 10 weeks, and a median of 3.5 weeks.

TEMPORAL RELATIONSHIP OF PREVIOUS PATCH USE TO CURRENT QUIT ATTEMPTS

The temporal relationship of previous quit attempts using Nicotinell TTS to the present attempt was noted by 195 out of 805 (24.2%) total respondents. The interval between the present attempt and the most recent past attempt is shown in table 3. For 151 (77.4%) of these respondents this interval was greater than six months. Only 16 (8.2%) of purchasers who had made a previous quit attempt using Nicotinell TTS had done so within the last three months. When duration of use was recorded, even if the current and previous courses of Nicotinell TTS were combined for these participants (which may well be inappropriate with a gap between courses), the longest combined usage would be 11 weeks. The mean duration of use overall for the previous course was 4.3 weeks, with a maximum duration of 10 weeks.

PATCH USAGE PATTERNS DURING CURRENT QUIT ATTEMPT

For 480 of 805 (59.6%) total respondents, this was their first purchase of Nicotinell TTS for the current treatment course. Prior purchases during the current course of Nicotinell TTS—that is, during the present quit attempt—were reported by 316 out of 805 (39.3%) total respondents.

Table 4 shows the usage pattern of the different patch strengths and the duration of use for 293 purchasers who had made prior purchases of Nicotinell TTS during the current treatment course and who recalled this information. The mean total duration of use of patches during the present attempt to quit smoking was 21.2 days, with a minimum of one day, a maximum of 91 days, and a median of 14 days. Only 10% of these respondents had used Nicotinell TTS for six weeks or more in the present attempt at the time of completion of the questionnaire.

CONCOMITANT SMOKING

Information about concurrent smoking was sought from the respondents who were purchasing Nicotinell TTS to continue their current treatment course. Of the 314 who gave information about concurrent smoking while using Nicotinell TTS during the present quit attempt, 225 (71.6%) reported that they had stopped smoking altogether, and 89 (28.3%) were still smoking. Of those who were still smoking, 85 reported on the number of cigarettes still smoked, which varied from one to 40 per day, with a median of five (compared with a median of 20 cigarettes per day before the current quit attempt). Analysis of the relationship between continued smoking while using Nicotinell, gender, and each of the number of years smoking, the number of cigarettes each day, and the age of the purchasers yielded no significant differences between the relevant subgroups.

SIDE EFFECTS

Information about side effects was sought from the respondents who were purchasing Nicotinell TTS to continue their current treatment course. Of the 301 who reported on side effects caused by Nicotinell TTS during their present quit attempt, 230 (76.4%) reported no problems. There were reports of side effects by 71 (23.6%) of the respondents. Of the total reports on side effects, skin irritation and sleep disturbances were the most common (table 5).

There were 23 purchasers who reported side effects and continued to smoke. There was no statistically significant relationship between concurrent smoking and the likelihood of experiencing side effects while using Nicotinell TTS.

Discussion

New Zealand was one of the first countries to allow non-prescription sale of transdermal nicotine; the product is classified as a pharmacy-only medicine, which restricts OTC sale to pharmacies. Pharmacists are expected to ask appropriate questions on sale of the product, and to provide counselling on its use.13 14 The pharmaceutical companies that market the products in New Zealand (Nicotinell TTS—Ciba-Geigy Pharmaceuticals; Nicabate—Marion Merrell Dow Pharmaceuticals) also provide support to pharmacists and consumers in the form of written material (starter packs) and telephone helplines. The products are priced OTC to correspond approximately with the cost of continuing to smoke at the consumer’s normal daily rate.

At the time of the start of the study, Nicotinell TTS had been available in New Zealand as a pharmacy-only medicine for approximately 18 months and Nicabate was just starting to be heavily marketed. Marketing was by direct advertising to the public in print and broadcast media, and to pharmacists by detailing and advertising in professional journals. At the time of the launch of Nicotinell TTS, the company (Ciba-Geigy New Zealand) provided extensive educational programmes to pharmacists on the use of the product.

Our study was initiated by open invitation to all community pharmacies in New Zealand. The total number of pharmacies generating participants was 149 from a total of 1108 contacted—a participation rate of 13.5%. It is difficult to say whether this was a “good” participation rate as this approach has not been attempted before. We were actually quite pleased with this response as there was no incentive for the pharmacies to become involved other than a willingness to assist in research. Given the busy and complex nature of community pharmacy practice, it was encouraging that a large number of pharmacists took the time and trouble to participate.

There was no attempt to differentiate between participating and non-participating pharmacies. It was not the intention of the study to assess the efficacy of the treatment or counselling provided by the pharmacists. The focus was on how transdermal nicotine was being used by purchasers in a non-prescription setting, and the pharmacists’ role was essentially to recruit agents for this research. For this reason the design was deliberately non-interventional.

It is possible that purchasers who agreed to participate were different in some way from those who did not. There was no attempt to assess this and the methodology would have been strengthened by a validation substudy. Anecdotally, pharmacists reported very few refusals when purchasers were invited to participate.

The study attempted to provide a “snapshot” of the ways in which consumers were using transdermal nicotine when purchased OTC. There was no attempt to establish efficacy and the study was not a clinical trial. It might rather be viewed as a form of postmarketing surveillance in a pharmacy setting whereby the “real life” use of the product was investigated. The methods employed were exploratory, there being relatively few reports of similar studies in the literature.15 20 The study has demonstrated that useful data can be obtained in this fashion. In some countries a proportion of the population may prefer direct purchase of some medicines in an OTC setting, avoiding the expense and inconvenience of a physician’s visit and reflecting an increasing move towards self-treatment.

OTC availability of transdermal nicotine products may lead to fewer opportunities for medical surveillance of their use, or for appropriate counselling and support to be offered to users. It could be argued that the effectiveness of transdermal nicotine as a quit-smoking aid is enhanced by intensive medical counselling, and there is evidence to support this view.30-34 On the other hand, a number of studies have demonstrated that less intensive or minimal intervention is still associated with successful use of the product when compared with placebo patches.15 35-40 In the context of this study we have assumed minimal intervention (routine initial questioning and counselling on first purchase) on the part of pharmacists selling transdermal nicotine, although we did not attempt to control or measure this aspect of the transaction.

In the overall context of smoking cessation strategies, a “stepped-care” approach for transdermal nicotine has been advocated.15 41 42 It could be argued that OTC availability allows an additional opportunity for some smokers who would initially prefer self-treatment as part of their quit-smoking attempt. The opportunity then exists for identification and referral of treatment failures to the next step of the strategy.

Apart from considerations of efficacy, precautions for nicotine usage still apply when the consumer has underlying cardiovascular morbidity or continues to smoke, or both. There are case reports of the onset of angina, myocardial infarction, and cerebral ischaemia in transdermal nicotine users, but the reported incidence of these is less than expected in a population of smokers, suggesting coincidence rather than a causal relationship.43-46 Continuing to smoke is inconsistent with the use of transdermal nicotine as an aid to quit, but little is known of the way in which products are used in practice (with or without prescription), and whether “at risk” patients are being identified and followed.

Another concern regarding the availability of transdermal nicotine is the potential for “transfer of addiction” from cigarettes to nicotine products. There are a number of reports of this occurring with nicotine gum, and some commentators predict that a similar potential exists with nicotine spray or inhaler products.26 27The release characteristics and pharmacokinetic profile of transdermal nicotine would appear to minimise the risk of addiction, and there is no evidence that this has developed in the trials performed to date.7 23 47 One of the aims of this study was to assess the potential for the development of “transfer of addiction” in the OTC use of transdermal nicotine.

Approximately 60% of purchases for the current course of Nicotinell TTS were by new users of the product. For those reporting previous attempts to quit smoking using the product, more than 90% had used it more than three months before the current quit attempt and fewer than 10% of such purchasers had made a quit attempt using Nicotinell TTS within the previous three months. Even if the current and previous courses of the product are combined for these participants, the longest combined usage would be 11 weeks. The maximum duration of use for the previous course was recorded as 10 weeks. Accordingly, we could find no evidence of usage of Nicotinell TTS for longer than the manufacturer’s recommended maximum of 12 weeks. These data suggest that there is no “transfer of addiction” from cigarettes to transdermal nicotine. It has to be acknowledged that these are not conclusive data and the only real way to address this issue would be through a prospective study.

It was of interest to note that the actual duration of patch use in the “real life” context in this study was about four or five weeks on average, considerably shorter than the manufacturers’ recommendations of up to 12 weeks of treatment with reducing patch strength. Pharmacists reported that the usual purchase was for one week’s supply at a time, with relatively few purchases for more than three weeks’ supply at a time. Perhaps this pattern of purchase could be exploited more effectively by pharmacists in terms of support to purchasers with their quit-smoking attempts. This purchase pattern suggests that encouraging compliance and sufficient use of the product is a greater problem than the potential for “transfer of addiction”.

Some 28% of respondents reported continued smoking while using transdermal nicotine, although the average number of cigarettes smoked per day was substantially less than that in their previous smoking history. The manufacturer’s instructions clearly state that purchasers should stop smoking altogether while using the patches.14 These instructions are meant to be reinforced by pharmacists when selling the product. No statistically significant relationship was found in this study between reported side effects with the use of transdermal nicotine and concomitant smoking while using the product.

Ideally, the use of transdermal nicotine should result in complete smoking cessation4; however, in many cases this obviously does not occur. Several authors have argued that concomitant smoking does not necessarily signify failure of the product6 48; others propose that early smoking while using transdermal nicotine is a strong predictor of failure to quit smoking.15 49 The reduction in intake of harmful cigarette smoke and the demonstration to the user that a substantial reduction in cigarette consumption can be achieved may be benefits in themselves. The cohort of transdermal nicotine users who continue to smoke may not be able to achieve abstinence without further counselling or intervention by health professionals. This reinforces the concept of a “stepped-care” approach to smoking cessation with the opportunity to identify those smokers who require more intensive therapy.41 42

Side effects were reported by 24% of Nicotinell TTS users in the current treatment course, with skin reaction and sleep disturbances the most frequently reported. These findings are consistent with previous studies.5 6 No serious adverse effects were described.

Although a number of purchasers reported previous medical conditions, mainly cardiovascular in nature, it did not appear that those who had pre-existing medical conditions experienced side effects more often than healthy respondents.

In summary, this study has provided useful preliminary data on the non-prescription availability of Nicotinell TTS. Within the limitations of the methods used, the actual duration of use of the product appeared to be shorter than that recommended by the manufacturer, and there was no evidence of transfer of addiction from cigarettes to transdermal nicotine. Concomitant smoking while using Nicotinell TTS was reported by a fairly high proportion (28%) of users; this did not, however, lead to an increased rate of reporting of side effects.