Measuring patient adherence/compliance to therapy has important value in clinical practice as well as research. In practice lack of adherence decreases clinical outcomes and in research it causes bias in findings.
International society of pharmacoeconomics and outcomes research defines patient adherence as "the consistency and accuracy with which a patient follows a recommended medical regimen, usually referring to a pharmacotherapeutic regimen.
One of the main issue hindering better clinical outcomes are lack of good patient adherence or compliance to therapy. In this age of increased patient rights, the patient could deny a better therapy due to various reasons. As a health care professional it is the duty of the pharmacists to work for improving patient adherence to their treatment. There are quality control and quality assurance measures to check and improve patient adherence. And adherence to therapy is a dynamic process, it varies time to time in the same patient, so achieving good adherence and maintaining it are equally important. Patient adherence to therapy plays a vital role in case of chronic treatments. It becomes more and more important if the disease of importance to the social health. Example, high adherence to antiretroviral drugs and anti-tubercular therapy decreases the chances of spread of HIV and TB infections. The adherence also has indirect social and family health relevance as in case of diabetes mellitus, arthritis, or psychiatric disorders, the patient become more disabled with lack of adherence to therapy and the burden on care takers increases. So eventually lack of patient adherence to therapy shall decrease their, familial, as well as societal quality of life.
There is couple of methods for measuring patient adherence;
* Direct observation
* Electronic monitoring
* Pill count method
* Prescription refill rate
Direct observation: When possible patients could take the medicines under the direct observation of health care professional. It is not convenient when patient have to take multiple doses in a day or frequently. This model is successfully practiced by Directly Observed Therapy Short-course (DOTS) in Revised National Tuberculosis Control Program in India. Recently some pharmacies are authorized by the authorities as DOTS centers in the country, this makes it convenient for the patient to stop by and take their medicines under direct observation. This method gives the true data on patient adherence.
Electronic monitoring: Microprocessor driven devised could be used along with medications to record and transfer the data of medicine consumption. This method will be convenient for the patients as it may not be convenient to write down about consumption of medicines always. Specially designed software could improve the accuracy of information on patient adherence. Electronic monitoring is the most widely used method for compliance assessment in clinical trials.
Pill count method: It is a simple method of counting how many medicines consumed by the medicines from the medicine packet/box of the patient. Patients are advised to bring the strips of medicines at the time of visit to health care professional. Some patients shall deliberately remove medicines which actually they did not consume.
Prescription refill rate: If all the prescription refills are electronically documented for all the pharmacies, this measurement will work out. Still it is not clear that patient is consuming all doses even if they get their medicines refilled.1
Attendance: Attendance for the follow up visits will give a rough idea about the adherence of the patient to medicines in chronic conditions.
Better clinical outcomes are almost always affected with complex issues. Taking medicines properly is only one aspect in patient adherence. Following proper lifestyle, diet pattern, use of health care technologies are some of the other contributing factors. Adherence to therapy involves convenience, familial, social, and psychological aspects. So, it is very relative and dynamic process which needs continuous monitoring. Detailed patient interviews shall bring a better picture about overall adherence of patients towards their health care.
Generally patients could be categorized in to non-compliers, partial compliers, compliers, and over compliers. These terms are self explanatory. Over compliers do more than the recommended, which may not be good all the times.
The value of adherence or compliance mostly depends on the nature of disease and its consequences. The consequences mainly include the disease burden on health as well as financial burden for treatment. The reasons for non-adherence could be lack of awareness, non-willingness, financial burden, frustration with long standing or fast growing disease, adverse drug reaction, social stigma, forgetfulness, inconvenience. Efficient counseling, patient reminders, and medication therapy management could improve patient adherence to treatment.1
1. Berger ML et al. Health care cost, quality and outcomes, ISPOR, 2003: 22-25.