Análisis descriptivo El lugar.

Table 3 presents the results of a two-step hierarchical regression analysis, in which the illness perceptions were regressed onto benzodiazepine use at T2. In Step 1 we entered the three demographic variables. Because we are primarily interested in which illness beliefs are related to amount of use and because past behaviour is a predictor for future behaviour (19), we did not enter benzodiazepine use at T1 in Step 1. It appeared that gender, age andIt appeared that gender, age and

educational level predicted benzodiazepine use at T2 (R2_{= .08; p < .01). InIn}

Step 2 the illness perceptions were entered. These variables added 6% to the explained variance (R2_{= .14; p < .01) with consequences (β = .18; p < .01)}

and control (β = .14; p < .05) being significant predictors of benzodiazepine use at T2.

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Table 3 Linear multiple regression analyses predicting benzodiazepine use at T2

Step Variables entered ß ß

1 Gender .19** .19** Age -.22** -.16 Educational level -.13* -.11 Length of use .10 .04 2 Illness identity .09 Psychological cause .02 Consequences .18** Control/cure .14* Timeline .04 R² .08 .14 R² Change .07 Model F 6.10** 5.09** ** p < .01 * p < .05

Discussion

The main findings of the present study were that, of the illness perceptions, consequences and control significantly predicted benzodiazepine use. Thus, the belief that complaints become more serious and the belief that patients would have little control over the outcome of their illness if they were not taking benzodiazepines, were related to a higher level of benzodiazepine use. This is in line with other studies describing the role of illness perceptions in health outcome (20-24). Although the data are prospective, the causal direction of the relationship cannot be interpreted with certainty. For instance, it cannot be ruled out that when patients use a higher dose of benzodiazepine, they strategically construe their illness as more serious. However, on the basis of theoretical considerations and empirical evidence, it is very plausible that illness beliefs have effects on well-being (7;8) and on behaviour (25).

The variance in benzodiazepine dosing that could be explained by the illness beliefs was only 6 % (R2_{=.06). Nevertheless, 6 % has a significant and}

relevant contribution when taking into account the large number of patients using benzodiazepines. In the Netherlands, 10-15% of the population use benzodiazepines on a regular basis, and 3% use them chronically (3). TheThe

number of prescriptions for benzodiazepines in 2003 was almost 11 million and the number of prescriptions for benzodiazepines is growing by 1% each year (1;20). In other words, if interventions were to succeed in changing illness beliefs in the direction of the illness being less serious, a maximum reduction of 6 % in benzodiazepine use would make a substantial difference. In addition, the 6 % variance must be considered against the background of other possible influences on dosing, such as doctors’ recommendations and social influences. Although many factors could have influenced and probably did actually influence benzodiazepine use between T1 and T2, the patients’ beliefs survived all these influences. This means that a patient’s perception of how the illness would be if he or she did not use benzodiazepines may be a robust and central factor in explaining benzodiazepine use.

The correlational results shed some light on the validity of the measures. The more complaints were perceived as being related to their illness, the more

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severely patients perceived their illness, as indicated by positive relations with the dimensions consequences and timeline. In addition, the longer patients thought their illness would last if they no longer used benzodiazepines, the less control they perceived and the more severely they evaluated their illness. The correlations were small to moderate and all in expected directions.

The sample consisted of chronic benzodiazepine users; they used benzodiazepines for an average period of twelve years. Many patients reported sleeplessness, tension, worry and anxiety as the main problems for which they used benzodiazepines. Most patients reported more than one complaint to be the reason for their use. These percentages do not necessarily reflect the actual medical indications for which they use the medicine but they illustrate the patients’ perspective. The fact that the present sample used benzodiazepines chronically is reflected by the high agreement to statements that, if they no longer used benzodiazepines, their illness would have severe consequences and would last longer. In addition, patients showed low agreement with the statements on having control on their illness. The combination of high seriousness (consequences and lasting longer) and low control in the case of no longer using benzodiazepines indicates their reliance on benzodiazepines.

Illness beliefs are expected to be related to benzodiazepine dosing through two different but related pathways. Firstly, the more serious an illness is perceived to be, the more intensive a cure should be to be effective. Secondly, the more serious an illness is perceived to be, the stronger the emotional reactions to the illness will be and the more benzodiazepines might be used to lower this distress. These relations are plausible but were not addressed in the present study. Future studies could include measures of medicine functions and well-being to test the hypothesized mediation.

To conclude, this study suggests that of the illness perceptions, consequences and control/cure predict benzodiazepine use. Interventions can now be developed in order to change these illness perceptions which may result in improved patient decision-making and adequate coping behaviour, which, in turn, may reduce reliance on benzodiazepines. On the one hand, interventions might aim at lowering the negativity of the consequences of the illness. For a large part this might be done by providing patients with alternative means to cope with their illness. In the case of benzodiazepine use, many patients might benefit from skills to lower worrying, to decrease distress or to support a good night’s sleep. On the other hand, interventions might aim to lower the perceived functions of benzodiazepine use, for example, to educate them about the tolerance patients develop for benzodiazepines that results in lowered effectiveness. In intervention studies it has been shown that self-management programs can produce significant improvements (29). Our findings contribute to the knowledge needed to decide which cognitions should then be targeted in such interventions.

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CHAPTER 4