For a drug to work, it must be taken correctly and regularly. It is not uncommon for patients to deviate from the doctor’s stated treatment regimen; as a result, the effect of the medicine can be called into question and with it the entire healing process.
Compliance and noncompliance
In science, the necessary adherence to therapy and the consistent following of the doctor’s instructions for taking the medication is called “compliance,” the opposite of which is called “non-compliance. “Thus, if a medication does not work, it is often due to the patient’s behavior. For example, patients read the package insert, are alarmed by the long list of possible side effects, and occasionally skip taking the tablets in the belief that they are actually doing themselves some good. Other patients start the therapy, but stop taking the medication as soon as the symptoms improve or undesirable side effects occur. The subjective feeling that “I’m doing quite well today” and forgetfulness also contribute to poor adherence to therapy. This is especially true if several medications have to be taken daily or if the treatment lasts for a longer period of time.
Noncompliance widespread
Studies repeatedly show that many patients’ adherence to therapy is not good. Depending on the clinical picture, the extent of this noncompliance is estimated to be between 12 and 35 percent. In particular, patients with respiratory diseases, diabetes mellitus and sleep disorders often do not adhere to their medication. In the case of prescribed long-term medication, the figures are even more alarming: only around 40 to 50 percent of patients with chronic diseases such as high blood pressure or asthma follow medical advice to take their medication. The consequences of poor adherence to therapy are often underestimated; they usually weigh far more heavily than the burden of any side effects.
Causes of noncompliance
There are many reasons why patients do not comply with medication: social, economic, disease-related, therapy-related, or personal factors may play a role. Well-known, for example, is the so-called “tooth brushing effect”, whereby the patient takes the medicine irregularly, but adheres correctly to the prescription a few days before a visit to the doctor. Or one speaks of so-called “drug vacations”, when predominantly on the weekend or on vacation the intake is suspended for a certain time.
Measurement of adherence to therapy
To be able to investigate the extent and causes of poor adherence to therapy, it is important to measure compliance. A distinction is made between direct and indirect methods of measurement:
- Direct method is the measurement of drug concentrations in the blood,
- Indirect methods include patient diaries, tablet counting (how many are left, so how many were taken in a given time period), and physician discussions with the patient about ingestion patterns.
Effects of non-compliance
The fatal effects of non-compliance with therapy can be seen, for example, in studies of patients who have had an organ transplant and are subsequently given permanent medication to suppress their own immune system so that it does not reject the new organ. On average, one in four patients does not follow the rules for taking these so-called immunosuppressants. As a consequence, the immune system fights against the new organ until it finally fails. Similar devastating consequences of lack of adherence to therapy have also been observed in patients infected with the HI virus. In addition to the health consequences, there is also an economic aspect: those who do not take their medication properly risk more frequent visits to the doctor, longer treatment times and hospital stays, which means, on the one hand, lost work and thus lost productivity and, on the other, a burden on the general healthcare system. The direct and indirect costs of non-compliance in Germany, for example, are estimated at 7.5 to 10 billion euros per year. By way of comparison, the total cost of health borne by statutory health insurers in 2006 was approximately 137 billion euros, illustrating the considerable magnitude of the costs caused by treatment noncompliance.
Education and care important
However, the patient is not always solely to blame for a lack of adherence to therapy.A poor relationship of trust between doctor and patient often also plays a role: the doctor provides too little information, and many patients know too little about their disease and its treatment and are not aware of how important it is to take their medication regularly. Patient education could significantly improve compliance. Sometimes family or friends also do not make it easy for the patient, for example when the disease is declared a taboo subject. On the other hand, an open approach to a condition, as well as support and motivation from family members, promotes the patient’s acceptance of his or her condition and its treatment. In addition to the physician, the pharmacist also plays an important role in the question of whether a patient demonstrates a high level of adherence to treatment. Recent scientific studies have shown that the interaction between patient, physician and pharmaceutical care by the pharmacist provides the basis for effective treatment adherence. Adherence to therapy is also an issue for pharmaceutical researchers. In the meantime, they have developed combination preparations for many diseases requiring the treatment of several drugs: instead of two or three different tablets, only one containing all active ingredients. Pharmaceutical forms that release an active ingredient continuously over a period of hours or days, known as sustained-release forms, also contribute to adherence to therapy. This is because, for example, it is sufficient to take the tablet once a day, for example at breakfast.
