"Just keep taking the tablets": adherence to antidepressant treatment in older people in primary care.
Maidment R, Livingston G and Katona C.;
Commented by , 25 Sep 2002
Aim of the study
To investigate the prevalence and correlates of adherence/compliance to antidepressants in over 65s in primary care.
Method
67 patients prescribed antidepressants in a single large rural general practice were interviewed by a research assistant using a range of questionnaires. Patients were excluded if the antidepressants were not for depression (eg pain), if they had insufficient English, or if they were too cognitively impaired to give informed consent.
The interviewer collected the following information:
- Demographic, depression and drug history.
- General Health Questionnaire (GHQ-28); Geriatric Mental State-Depression Scale; National Adult Reading Scale; and Mini-Mental State Examination.
- The Questionnaire on Patient Education; UKU Side Effects Rating Scale; Beliefs about Medicines Questionnaire; and Schedule for Assessing the Three Components of Insight.
- Adherence was assessed using the 5-point Global Adherence Measure.
Adherence was analysed statistically as the dependent variable. Backward linear regression was used to identify independent predictors of adherence.
Results
111 elderly patients on antidepressants in the practice were identified via the database and confirmed by their GP to be eligible. 13 were excluded because the prescription was not for depression or they could not give consent. 67 out of 98 eligible were interviewed; 22 refused participation, 5 carers refused participation, 3 were uncontactable, and 1 had insufficient English.
Of the 67 patients completing the study, only 45 (67%) were fully adherent. Seven were mostly adherent, three adhered sometimes, three rarely and nine never. The linear regression suggested that adherence increased with information given and cognitive impairment, and decreased with concerns about taking antidepressants and severity of side effects.
The mean time on antidepressants was four-and-a-half years, and most patients were taking medication for other conditions. 49% were on SSRIs, 43% on tricyclics.
Discussion
It is known that some older people are meticulous in taking their medication, others are not for a variety of reasons. This is the first study assessing adherence to antidepressants in older people, previous studies have looked at discontinuation rates only.
The results suggest that ⅓ of older patients stop antidepressants completely, and ⅓ of the remainder appear to be adherent, but are not.
These results are broadly in line with adherence in older people for other (non-antidepressant) medication, and your younger adults taking antidepressants. Interestingly, adherence in cognitively impaired people was improved in this study, probably because their carers were monitoring and ensuring they took their tablets.
The key points that the authors infer from this study are that:
- Education, eliciting and addressing specific concerns about antidepressant medication, and choosing medication that minimises side effects, will improve adherence in older people.
- Improving outcomes for patients with depression requires a process of care to be adopted, similar to that already made in other chronic diseases.
In summary, non-adherence to antidepressant medication is a significant problem in older patients. There is little point in prescribing if a patient is not going to take the medication reliably. The reasons given in this study by older people for not adhering to antidepressants could potentially be addressed by careful education and follow-up addressing concerns and side effects.