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Keywords:

  • adherence;
  • compliance;
  • IBD;
  • ulcerative colitis;
  • colitis;
  • Crohn's;
  • medication;
  • treatment

Abstract

  1. Top of page
  2. Abstract
  3. MATERIALS AND METHODS
  4. RESULTS
  5. DISCUSSION
  6. CONCLUSIONS
  7. REFERENCES

Background: Nonadherence has been reported in over 40% of patients taking maintenance therapies (MT) for inflammatory bowel disease (IBD). Studies in other illness groups have shown that nonadherence is related to negative attitudes to treatment. The aim of this study was to assess patients' attitudes to MT for IBD (beliefs about personal need for MT and potential adverse effects) and to identify whether such beliefs are associated with adherence to MT.

Methods: A cross-sectional survey was conducted in which 1871 members of the National Association for Colitis and Crohn's Disease (NACC) completed validated questionnaires assessing beliefs about MT and adherence to MT.

Results: Low adherence to MT was reported by 29% of participants and was associated with doubts about personal need for MT (odds ratio [OR] = 0.56; 95% confidence interval [CI]: 0.48–0.64; P < 0.001) and concerns about potential adverse effects (OR = 1.66; 95% CI: 1.42–1.94; P < 0.001). Attitudinal analysis showed that while almost half (48%) of the participants were “accepting” of MT (high necessity, low concerns), a large proportion of the sample (42%) were “ambivalent” about MT (high necessity, high concerns), 6% were “sceptical” (low necessity, high concerns) and 4% were “indifferent” (low necessity, low concerns). Compared to those who were “accepting” of MT, participants in all 3 other attitudinal groups were significantly more likely to be nonadherent.

Conclusions: The way in which patients judge their personal need for MT relative to their concerns about MT can be a significant barrier to adherence. Interventions to facilitate optimal adherence to MT for IBD should address such perceptual barriers.

(Inflamm Bowel Dis 2008)

Many treatments effectively reduce relapse rates in patients with IBD1–3 but nonadherence rates of over 40% compromise this effectiveness.4–8 A number of demographic and clinical factors have been associated with nonadherence in IBD.9 Being single,4 male gender,4 3 times daily dosing,7 full-time employment,7 symptomatic remission,7, 10, 11 disease duration,5, 6, 12, 13 and variations in class of medication taken6, 14 have all been associated with lower levels of adherence in IBD. These studies help us to identify “at risk” groups, but clinical and sociodemographic factors are largely unchangeable and further research is needed to identify causes of nonadherence that can be changed. Systematic review of interventions to facilitate adherence have reported disappointing effects and called for more innovative approaches15 that address the proven causes of nonadherence in particular illness groups.16

The causes of nonadherence can be summarized as unintentional and intentional.17 Unintentional nonadherence occurs when the patient intends to take the treatment, but is prevented from doing so by limitations in capacity and resources (eg, forgetting, poor comprehension, lack of funds, etc). Intentional nonadherence, however, occurs when the patient decides not to take medication as advised, and can be understood in terms of preferences and beliefs. While unintentional nonadherence is common among those with IBD,6, 18, 19 intentional nonadherence has also been found to be prevalent among this patient group.13, 18 It follows that interventions to facilitate adherence to medication will be more effective if they address the perceptual factors (eg, beliefs and preferences) influencing motivation to start and continue with treatment, as well as the practical factors (eg, capacity and resources) influencing patients' ability to implement instructions to follow the agreed treatment plan. To facilitate the use of this “Perceptual and Practicalities approach”20 in routine clinical practice, busy clinicians require a simple framework for conceptualizing and understanding the key beliefs influencing adherence. The Necessity Concerns Framework (NCF)21 shows promise in this respect. The NCF posits that treatment adherence is associated with the way in which patients judge their personal need for a prescribed treatment relative to their concerns about its potential adverse effects.

Studies across a range of long-term conditions including renal disease,22 asthma,23, 24 HIV,25, 26 and depression27, 28 have demonstrated the utility of the NCF, with nonadherence related to doubts about personal need for treatment and concerns about potential adverse effects. Moreover, patients' judgments about prescribed medications may be influenced by more general attitudes to pharmaceuticals as a whole (eg, perceptions that medicines are fundamentally harmful, addictive poisons which are overused by doctors).29 Negative attitudes to medicines appear to be prevalent within the community, with many patients being suspicious of medicines.

Few studies have assessed beliefs about medicines among inflammatory bowel disease (IBD) patients,9 but there is some evidence that these issues are also relevant in IBD,30 with negative beliefs about medicines related to nonadherence.11 The aim of this study was to use the NCF to gain insight into the beliefs that are held about maintenance therapies (MT) prescribed for IBD, and to explore the associations between such beliefs and adherence to treatment.

MATERIALS AND METHODS

  1. Top of page
  2. Abstract
  3. MATERIALS AND METHODS
  4. RESULTS
  5. DISCUSSION
  6. CONCLUSIONS
  7. REFERENCES

Design

Approximately 5900 questionnaires were posted by random allocation to provide a cross-sectional survey of the 29500 members of the National Association for Colitis and Crohn's Disease (NACC).

Measures

Demographic and Clinical Details

Respondents were asked to specify their gender, age, diagnosis (ulcerative colitis [UC], Crohn's disease [CD], or other), length of time since diagnosis, the number of IBD-related visits to their general practitioner in the previous year, and the number of outpatient and inpatient IBD-related visits in the previous year. Participants were also asked to indicate which medication(s) they were currently being prescribed as ongoing maintenance treatment for IBD.

Adherence to Maintenance Medication

Reported adherence to medication was assessed using a 4-item Medication Adherence Report Scale (MARS).23 The MARS has been used to assess medication adherence in a variety of illness populations,23, 31–34 including IBD.14 An example of an item from the MARS is “I decide to miss a dose of these medicines.” Respondents indicate their degree of agreement with each statement about medicine-taking on a 5-point Likert type scale, ranging from always [1] to never [5]. Scores for each of the 4 items were summed to give a total score ranging from 4 to 20, with higher scores indicating higher levels of adherence. Participants in this study were categorized into high and low adherers with those scoring between 4–16 classified as low adherers, and those who scored above 16 classified as high adherers.

Specific Beliefs About MT and Medicines in General

Patients' beliefs about medication prescribed specifically for IBD, and attitudes to medicines in general, were assessed using the Beliefs about Medicines Questionnaire (BMQ).29 The “BMQ Specific” comprises 2 subscales assessing patients' beliefs about the necessity of a prescribed medication for controlling their illness, and their concerns about the potential adverse consequences of taking it. Examples of items from the necessity scale include “My health at present depends on this medicine” while an example item from the concerns scale includes “I sometimes worry about becoming too dependent on this medicine.” Respondents indicate their degree of agreement with each individual statement on a 5-point Likert scale, ranging from strongly disagree [1] to strongly agree [5]. A mean score for each subscale was computed by dividing total scores for that scale by the number of items in the scale, giving a mean score range of 1–5 for both the necessity scale (8 items) and the concerns scales (9 items).

The “BMQ General” comprises 3 4-item scales that evaluate beliefs that medicines are harmful, addictive, poisons, which should not be taken continuously (General-Harm), beliefs that medicines are overused by doctors (General-Overuse) and beliefs about the benefits of medicine (General-Benefits). The Sensitive Soma Scale was also included to assess perceptions of personal sensitivity to the adverse effects of medication. Respondents indicate their degree of agreement with each individual statement about medicines in general and perceived sensitivity on a 5-point Likert scale as described for the “BMQ Specific.” Mean scores for each subscale are computed by dividing total scores for that scale by the number of items in the scale, resulting in a mean score range of 1–5 for each subscale.

IBD Chronicity

An item from the Illness Perceptions Questionnaire (IPQ-R)35 was included to measure patients' beliefs about the chronicity of IBD (“My IBD will last for a long time”). Respondents indicate their degree of agreement with this statement on a 5-point Likert scale, ranging from strongly disagree [1] to strongly agree [5].

RESULTS

  1. Top of page
  2. Abstract
  3. MATERIALS AND METHODS
  4. RESULTS
  5. DISCUSSION
  6. CONCLUSIONS
  7. REFERENCES

Demographic and Clinical Details of Sample

Completed questionnaires were returned by 1871 members of the NACC, resulting in a 32% response rate. In all, 63% of respondents were female and the mean age was 50 (SD = 16.0); 49% of the sample had UC, 45% CD, and 6% other colitis (eg, collagenous; see Table 1).

Table 1. Demographic and Clinical Variables for the Sample (n=1871)
FactorMeanSD
Age50.115.9
 n%
Gender (female)115663.4
Diagnosis  
 Ulcerative colitis88348.9
 Crohn's disease80944.8
 Other diagnosis1146.3
GP visits for IBD in last year  
 None64635.7
 Once31817.6
 Twice27415.1
 Three/ more57331.6
Outpatient hospital visits for IBD in last year  
 None32918.1
 Once44024.3
 Twice43724.1
 Three/ more60833.5
Inpatient hospital visits for IBD in last year  
 None145280.1
 Once23212.8
 Twice794.4
 Three/ more502.8
Time since diagnosis of IBD  
 Within last year633.5
 1-2 years1437.9
 3-4 years22912.7
 5-9 years41322.9
 10-19 years52729.2
 Over 20 years43223.9

Adherence to MT Prescribed for IBD

Unintentional nonadherence was evident with 28% of the sample reporting that they forgot to take their MT at least sometimes, often, or always. Intentional nonadherence was also common, with nearly a third (32%) of the sample reporting that they altered the dose of their MT, while 17% of the sample reported that they decided to miss doses of MT. Almost 1 in 10 (9%) of the sample reported that they had stopped taking their MT altogether at least sometimes, often or always (Fig. 1).

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Figure 1. Percentage of patients who reported that they sometimes, often, or always engaged in each of 4 nonadherent behaviors.

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Specific Beliefs About MT

Dichotomizing the necessities and concerns scales at the mid-point showed that 1 in 10 (10%) of participants had low perceived need for MT (ie, scored below the mid-point on this scale). More specifically, when looking at the individual necessity items it was found that 18% of participants disagreed that their lives would be impossible without these medicines and 14% of participants disagreed that without this medicine they would be very ill. Concerns about MT were higher still with 48% indicating concerns about the potential adverse effects of medication prescribed for IBD (ie, scoring above the mid-point on this scale). When exploring individual concerns it was found that 73% of the sample were concerned about the long-term effects of MT, and over half (52%) of participants were concerned about dependency on MT.

Attitudinal Analysis

Participants were categorized into attitudinal groups (27) based on their beliefs about MT (Fig. 2). While nearly half (48%) of the sample were found to be “accepting” of MT (high necessity, low concerns), a large proportion of participants (42%) were “ambivalent” about MT (high necessity, high concerns). Those who were skeptical about MT (low necessity, high concerns) and those who were indifferent about MT (low necessity, low concerns) comprised the smallest groups, at 6% and 4%, respectively.

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Figure 2. Attitudinal analysis of beliefs about maintenance treatment (MT).

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Beliefs About Medicines in General

Beliefs about the harmfulness of medicines in general were consistently low, with only 16% holding the view that most medicines are poisons, while 13% agreed that most medicines are addictive. Beliefs about the overuse of medicines in general were more pronounced with 31% participants agreeing that doctors place too much trust in medicines, 33% agreeing that doctors used too many medicines, and 42% holding the view that doctors would prescribe fewer medicines if they spent more time with patients. Many participants endorsed the benefits of medicines; for example, 87% endorsed the view that medicines help many people live longer. When asked about personal sensitivity to medicines, nearly half of the sample reported that they had had a bad reaction to medicines in the past (45%), while a fifth reported that even very small amounts of medicine could upset their body (21%).

Beliefs About the Chronicity of IBD

Strong beliefs about the chronicity of IBD were evident with 92% of the sample agreeing that their IBD would last for a long time (mean score 4.68; range 1–5; SD 0.71).

Beliefs About MT and Adherence

Low adherence to MT was found to be associated with doubts about personal need for MT (odds ratio [OR] = 0.56; 95% confidence interval [CI]: 0.48–0.64; P < 0.001) and concerns about potential adverse effects (OR = 1.66; 95% CI: 1.42–1.94; P < 0.001). Mean scores (and 95% CI) for perceived need for MT and concerns about MT across high and low adherers are shown in Figure 3.

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Figure 3. Beliefs about maintenance treatment (MT) necessity and MT concerns for high and low adherers.

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Attitudinal Groups and Adherence

Comparisons of reported adherence were then made across the 4 attitudinal groups (accepting, ambivalent, skeptical, indifferent). Significant differences between groups in adherence to medication were found (F(3,210.44) = 36.99, P < 0.001)*. Post-hoc tests revealed that compared to those in the “accepting” group, those in all 3 other attitudinal groups reported significantly lower adherence (all significant at the 0.001 level). Furthermore, those in the “ambivalent” group reported higher adherence than those in both the “skeptical” group (P < 0.001), and the “indifferent” group (P < 0.01). While those who were skeptical reported the lowest levels of adherence, differences between the skeptical and indifferent group fell short of statistical significance (P > 0.05) (Fig. 4).

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Figure 4. Adherence to maintenance treatment (MT) across attitudinal groups.

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Predictors of Low Adherence

Logistic regression analysis was performed to assess the role of demographic and clinical variables and treatment beliefs (attitudinal groups) in the prediction of adherence. Demographic variables were entered in block 1, followed by clinical variables in block 2 and attitudinal groups in block 3 (Table 2). Low adherence was associated with younger age, a diagnosis given 5 or more years ago, and fewer outpatient visits in the previous year (less than 3 versus 3 or more). Treatment beliefs (attitudinal groups) were predictive of low adherence independent of sociodemographic and clinical predictors. Compared to those who were “accepting” of MT, low adherence was associated with an ambivalent attitude about MT (OR = 1.79; 95% CI: 1.37–2.33; P < 0.001), being skeptical about MT (OR = 4.59; 95% CI: 2.79–7.53; P < 0.001), and indifference about MT (OR = 3.87; 95% CI: 2.26–6.64; P <.001).

Table 2. Logistic Regression Model for Predictors of Low Adherence to MT for IBD
 OR95.% CISignificance
LowerUpper
1DemographicsGender.82.641.060.138
  Age.98.97.990.000
2Clinical variablesDiagnosis.90.691.150.379
  Time since diagnosis1.961.432.690.000
  GP visits1.06.791.420.694
  Outpatient visits.61.45.830.001
  Inpatient visits.77.551.080.131
3Attitudinal groupsCompared to accepting    
  Ambivalent1.791.372.330.000
  Skeptical4.592.797.530.000
  Indifferent3.872.266.640.000

Potential Origins of Beliefs About MT

Significant correlations were found between specific beliefs about MT prescribed for IBD and attitudes toward pharmaceuticals in general (Fig. 5). Increased concerns about MT were associated with negative attitudes about pharmaceuticals in general (ie, increased beliefs in the harm and overuse of medicines, reduced belief in the benefits of medicines, and increased beliefs in personal sensitivity to medicines). Increased beliefs in personal need for MT were associated with positive attitudes toward pharmaceuticals in general (ie, lower beliefs in the harm and overuse of medicines, increased beliefs in the benefits of medicines, and reduced beliefs in personal sensitivity to medicines). Increased beliefs in personal need for MT were also found to be associated with increased beliefs in the chronicity of IBD.

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Figure 5. Pearson correlation coefficients between adherence to maintenance treatment (MT), beliefs about MT, beliefs about medicines in general, and IBD chronicity beliefs.

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Subanalysis: The Role of Drug Type in Beliefs About Treatment and Adherence

For those participants on monotherapy it was possible to explore the role of drug type (5-aminosalicylate [5-ASA] medicines, immunosuppressant drugs, steroid medications) in beliefs about medicines and reported adherence. There was a significant effect of drug group upon beliefs about sensitivity to medications in general (F(2,135.69) = 9.285, P < 0.001)*. That is, participants exclusively taking steroids reported significantly higher beliefs in their sensitivity to medicines compared to those exclusively taking immunosuppressive medicines (P < 0.05) or 5-ASA medicines (P < 0.001). Differences between beliefs about sensitivity to medicines in general between those taking immunosuppressive medicines and 5-ASA medicines were not significant (P > 0.05).

No significant differences were found in beliefs about the necessity of medication across the 3 drug groups (F(2,999) = 0.68; P > 0.05). There was, however, a significant effect of drug type on concerns about treatment for IBD (F(2,997) = 17.68; P < 0.001). Participants prescribed steroids alone reported the highest concerns about their medication, significantly more so than those exclusively taking 5-ASA medicines (P < 0.001). Differences in concerns between those taking steroids and those taking immunosuppressants did not reach significance (Fig. 6).

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Figure 6. Concerns about maintenance treatment (MT) across drug groups.

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Reported adherence to medication was also found to differ significantly across therapeutic modality (F(2,145.37) = 36.11; P < 0.001)*. Participants solely prescribed steroid medication reported the lowest adherence, significantly less so than those exclusively taking immunosuppressive medication (P < 0.001) who were the most adherent of the 3 drug groups. Differences in adherence between those taking steroids exclusively and those only taking 5-ASA medications did not reach significance (P > 0.05) (Fig. 7).

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Figure 7. Adherence to maintenance treatment (MT) across drug groups.

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DISCUSSION

  1. Top of page
  2. Abstract
  3. MATERIALS AND METHODS
  4. RESULTS
  5. DISCUSSION
  6. CONCLUSIONS
  7. REFERENCES

This is the largest study of patient adherence in IBD and it provides an insight into some of the drivers for patient behavior. Many participants recognized the necessity of maintenance therapy but some patients clearly had doubts about their personal need for treatment, and almost three-quarters of the sample expressed concerns about the long-term effects of their treatment. Similar concerns have been reported in other patient groups including those with asthma, cardiac disease, renal failure, cancer, and HIV.22, 23, 26, 36 Both intentional and unintentional nonadherence was reported by many participants; increased doubts about personal need for MT, and increased concerns about the MT regimen, were found to be associated with nonadherence.

Participants were categorized into attitudinal groups (accepting, ambivalent, skeptical, indifferent) based on their beliefs about MT. Further analysis across these groups revealed that participants who were “accepting” of MT reported the highest levels of adherence, significantly higher than all other attitudinal groups; those who were “skeptical” about MT (low perceived need, high concerns) were the least adherent of the attitudinal groups. Multivariate analysis showed that attitudinal group significantly predicted nonadherence independent of clinical and demographic factors. Moreover, when compared to those who were accepting of MT, all other attitudinal groups (ambivalent, skeptical, indifferent) were associated with nonadherence.

Analysis of patient demographics and clinical data identified that younger age, longer disease duration (diagnosed 5 or more years ago), and fewer outpatient visits in the previous year (less than 3 versus 3 or more) were associated with poor adherence. Previous research has also reported poorer adherence among younger IBD patients.7, 12 Gender was unrelated to adherence in our study, concurring with previous studies finding no such association.13, 18 Evidence for an association between gender and adherence to treatment for IBD is somewhat inconsistent; a higher incidence of nonadherence to treatment among men with IBD has been reported previously,4 while others have found that females are less adherent to IBD maintenance therapy.14, 37

We found that greater disease duration predicted nonadherence, as did Lopez et al,13 but others report that longer IBD disease duration correlates with improved adherence to medication.5, 6, 12 There were no differences in adherence between UC and CD patients. Those patients with fewer hospital visits were found to be less adherent, but they also represent patients with less active disease.

The clinical and demographic characteristics of nonadherent patients are extensively published9 but largely unchangeable, hence the need for more intelligent assessment. Treatment beliefs are not fixed and offer a realistic opportunity to improve adherence to MT. Understanding the origins of patient beliefs will shape targeted interventions for those patients in the ambivalent, skeptical, and indifferent groups whose adherence levels are significantly lower than patients in the accepting group. This qualitative research will be undertaken by our group in the near future.

Beliefs about IBD were found to influence beliefs about prescribed treatment. Participants who believed in the chronicity of IBD reported greater personal need for MT, whereas weaker beliefs in the longevity of IBD were associated with doubts about personal need for MT. Patients may doubt their personal need for MT because the notion of IBD as a chronic condition, needing continuous treatment, may be at odds with their experience of it as an episodic problem.

We also explored the role of drug class on beliefs about treatment and adherence in those patients receiving monotherapy. No differences were found in beliefs about the necessity of medication across drug groups, but concerns about MT varied across drug groups. Participants who were taking long-term steroids had the highest concerns about their medication and these participants reported the lowest levels of adherence. Previous research has reported that steroids are viewed more negatively than other “regular” IBD medication.30 We found that participants exclusively taking 5-ASA medicines were the least concerned about their MT, which is in line with previous work reporting minimal concerns about 5-ASA medicines.30 Patients were most adherent to immunosuppressants, which is a finding that has also has been reported previously.1, 6, 14

Limitations

All participants in this study were members of the NACC chosen at random on a 1-in-5 basis. These patients will not be representative of the IBD population as a whole but there is no reason to think that their beliefs about medication necessity and concerns about MT and adherence behavior would be different from the general IBD population. Previous research has reported no differences in adherence rates between NACC members and nonmembers.7 We were disappointed with the questionnaire response rate of 32%, which is typical for this type of study. While we are unable to compare the responders to the general NACC population demographics, our study patient demographics are close to predicted, with a slight excess of females. Our interest lies in the relationship between patient beliefs and adherence, and the results are in line with studies in other chronic conditions.22, 25–28, 34, 36, 38, 39

This study employed a self-report measure of adherence. While it has previously been argued that self-report measures of adherence run the risk of obtaining socially desirable responses, the MARS is framed in a nonjudgmental manner in a bid to minimize occurrences of this. If anything, these measures are likely to underreport nonadherence, resulting in an acceptable type 1 error.

CONCLUSIONS

  1. Top of page
  2. Abstract
  3. MATERIALS AND METHODS
  4. RESULTS
  5. DISCUSSION
  6. CONCLUSIONS
  7. REFERENCES

This is the largest adherence study ever undertaken in patients with IBD and it provides valuable information about maintenance treatment beliefs. A recent systematic review reported a lack of medication adherence data in CD40; half of our participants reported a diagnosis of CD. Adherence to maintenance therapy reduces relapses10 and probably also protects against colon cancer.41 This study has provided support for the NCF in the context of nonadherence to MT for IBD. The response rate of this survey was low, and as such it is likely that the true extent of nonadherence in this instance is underestimated. If nonadherence to maintenance treatment for IBD is even more prevalent than reported in this study, then our findings have even more significance. The importance of research exploring the effect of treatment beliefs on adherence is paramount; beliefs are modifiable,42 but sociodemographic and clinical factors are largely unchangeable. Interventions to facilitate optimal adherence to maintenance treatment in IBD will need to address perceptual barriers to adherence (doubts about personal need for MT and concerns about MT) as well as practical barriers to adherence (eg, forgetfulness or regimen complexity).

  1. 1

    Welch's F statistic is reported (Levene's statistic was significant, indicating violation of the assumption of homogeneity of variance).

  2. 2

    Games-Howell post-hoc statistics are reported due to differences in population variance and sample size.

REFERENCES

  1. Top of page
  2. Abstract
  3. MATERIALS AND METHODS
  4. RESULTS
  5. DISCUSSION
  6. CONCLUSIONS
  7. REFERENCES
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