What is ADHERENCE?
The process or condition of adhering.
Adherence in Health/Clinical Pschology investigates why medical patients do not adhere to the advice they are given by doctors. We will investigate:
- Reasons why patients do not adhere & evidence
- Measuring adherence and non-adherence & evidence
- Improving adherence & evidence.
Reasons why people DO NOT adhere
Why do people choose not to adhere?
-Rational non-adherence: People make a rational decision not to adhere to medical advice because they believe it is not in their best interest to do so. In most cases they may have a good reason not too e.g.
- They have reason to believe the treatment is not working.
- The side effects are unpleasant or effect the quality of their lives.
- There are practical barriers to treatment such as cost or social difficulties.
-They may want to check that the illness is still there by not taking the medication to look for symptoms.
Rational non-adherence: EVIDENCE
Lowe and Raynor (2000)
Aim: To assess the extent to which intentional non-adherence to medical regimes is present in elderly patients.
Procedure: Self Report was used to question 161 patients aged 65+ and taking three or more drugs in their home environment on the medicines they take, the dose taken and the frequency. Responses were then compared to the medical records of the patients and they were asked about any discrepancies between their responses and the records.
Results: There was a discrepancy in 86 cases (53%). In 28 cases the discrepancy was due to administrative error and in three cases it was due to patient confusion. However, the remaining 55 pps had made a rational decision to alter their medication.
Reasons given: Side effects, adjustment according to symptoms, drug not working, adjustment to suit daily routine, drug not needed, didn't like taking the tablet, self limiting condition, misunderstanding, concern about cost.
Cognitive/Behavioural Theories of Adherence.
Locus of Control - Rotter 1966
This study found that the more a person feels in control the more likely they are to comply with their treatment programme. If we have an INTERNAL locus of control then we believe that we are in control of what we do and thus have a higher self efficacy - a greater belief that what we do makes a difference.
Psychoanalytic explanations for reasons why individuals do not adhere is that they are in avoidance/denial of the problem in the first place.
Here is a list of the ways that we can measure adherence and the issues for each method.
-Self Report - demand characteristics may occur and could be invalid as adherence is a personal topic so people are possibly going to be untruthful.
-Therapeutic Outcome - Have they got better? It doesn't prove that they have been adherent.
-Ask the doctor- Would doctors realistically have that knowledge?
-Mechanical methods- bottle may have leaked, just because it has been taken out of the bottle does not mean the patient consumed it.
-Pill and bottle count - Patients could have thrown them away/ overdosed.
-Biochemical testing - Other factors may affect samples etc, snapshot study?
Measuring Adherence - Evidence
Chung and Naya 2000 Study
Aim: To measure objectively adherence rates of asthma sufferers. Do pps take their medication regularly and at the correct time of the day?
Design: Longitudinal study (12 weeks)
Sample: 57 asthma patients in London
Procedure: An electronic track cap was put into the medicine bottle which recorded date and time of each use of the bottle. Pps were told adherence rates were being measured but were not informed of the track cap. Medicine was supposed to be taken twice a day, so a person was seen as adheering to the treatment if track cap was used twice a day, 8 hrs apart. The number of pills left at the end of 12 weeks counted.
Results: Over the 12 week period adherence was quite high - median 71%. The count of pills returned showed a higher adherence rate at 92%. (10 pps dropped out)
Conclusion: Adherence rates of asthma patients is high. The majority followed their prescribed treatment programme.
Measuring Adherence - Evidence
Lustman et al (2000)
Aim: To assess the efficacy of the anti-depressant Fluoxetine in treating depression by measuring glycemic control.
Method: A randomised controlled double blind study.
Sample: 60 pps with type 1 or type 2 diabetes and diagnosed with depression.
Procedure: Patients were randomly assigned to either fluoxetine or placebo group. Pps were assessed for depression using psychometric tests and their adherence to their medical regime was measured by measuring their GHb levels which indicated their glycemic control.
Results: Patients given fluocetine reported lower levels of depression. They also had lower (nearer to normal) levels of GHb, which indicated their improved adherence.
Conclusions: Measuring GHb in patients with diabetes indicates their level of adherence to prescribed medical regimes. Greater adherence was shown by patients who were less depressed, and previous research has suggested that reducing depression may improve adherence in diabetic patients.
How can we improve adherence in patients?
- Use a media campaign to raise self efficacy that it is better to adhere.
Cowpe study - where a chip pan advert led to adherence from the public in using them safely.
- Make sure your patient is not depressed.
Lustman study - diabetes and insulin.
- Use a fear appeal (mild) to almost scare pps into adhering.
Tooth decay study - mild fear appeal worked the best.
- Inform the pps that their adherence is being monitored.
Track cap study led to higher rates of adherence in asthma sufferers.
Use the Behaviorist Approach to improve adherence
- Feedback and self monitoring - the patients get regular reports on the state of their health so reinforcing their adherence.
- Contingency contracts: the patient negotiates a contract with the health worker concerning goals and rewards for achieving these goals.
- Modelling: The patient sees someone else who is successful in a support group or as a mentor.
- Direct reinforcements or incentives - e.g. being given money to continue a programme or come off drugs.
- Punishment in NY - Laws were changed so that people had to take the treatment (for tuberculosis) and come to the clinic and be seen to take it or force compulsory admission to hospital.
Improving Adherence to taking medication for asthm
Watt et al (2003)
Aim: To see if using a Funhaler can improve children's adherence to taking medication for asthma.
Methodology: A field experiment. Adherence is measured by self-report and physiological measures of calculating the volume of air inhaled by the child and the quantity of medication absorbed.
Sample:32 australian children (10 boys and 22 girls) aged 1.5 to 6 years, mean age 3.2 years. Had all been diagnosed with asthma and prescribed drugs delivered by pressurised metered dose inhaler. The parents gave informed consent.
Design: Repeated measures design, each pp had one week using normal pMDI inhaler then one week using the funhaler.
Procedure: Each child given a normal inhaler to use for one week, and the parents were given a questionnaire to complete. The second week, the children used the funhaler and the parents were given a questionnaire with matched questions at the end of the 2nd week.
Findings: 38% more parents were found to have medicated their children the previous day when using the funhaler, compared to the existing treatment. 60% more children took the recommended dose for each delivery compared to the normal inhaler.
Conc: By making the medical regime fun, adherence in children can be improved.