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Failure to take prescribed medicine for chronic diseases is a massive, world-wide problem

Patients fail to receive needed support

Poor adherence to the long-term treatment of chronic diseases, like cardiovascular diseases, HIV/AIDS, or depression is an increasing, world-wide problem of striking magnitude. Adherence problems are observed in all situations where the self-administration of treatment is required, regardless of the type of disease.

A number of rigorous reviews have found that in developed countries, adherence among patients suffering from chronic diseases averages only 50%, and it is even lower in developing countries

In Gambia, China, and the United States only 27%, 43% and 51%, respectively, of patients adhere to their medication regimen for high blood pressure. Similar patterns have been reported for other conditions such as depression (40%-70%), asthma (43% for acute treatments and 28% for maintenance), and HIV/AIDS (37%-83%).

These are some of the findings of the WHO’s newly published report entitled Adherence to long-term therapies: evidence for action.

"Poor adherence is the primary reason for not achieving the full health benefits medicines can provide to patients. It causes medical and psychosocial complications of disease, reduces patients’ quality of life, increases the likelihood of development of drug resistance and wastes health care resources,“ said Dr Derek Yach, Executive Director, Noncommunicable Diseases and Mental Health, World Health Organization. “Taken together, these direct consequences impair the ability of health care systems around the world to achieve population health goals.”

In the United States, the United Kingdom and in Venezuela, only 30%, 7% and 4.5%, of treated patients, respectively, had good control of blood pressure. In Sudan, only 18% of non-adherent patients achieved good blood pressure control compared to 96% of those who adhered.

The adherence problem is set to expand as the worldwide burden of chronic diseases increases. Noncommunicable diseases (e.g. cardiovascular disease, cancer, diabetes), mental health disorders, HIV/AIDS and tuberculosis combined represented 54% of the global burden of illness in 2001 and are expected to exceed 65% in 2020.

"Better adherence will not threaten health care budgets. On the contrary, adherence to those medicines already prescribed will result in a significant decrease in the overall health budget," said Dr Eduardo Sabaté, Medical Officer, WHO. “This is due to the reduction in the need for more costly interventions, such as frequent and longer hospitalizations, unnecessary use of emergency room and highly expensive intensive care services.” Rational use of medicines means good prescribing and full adherence to the prescriptions.

Patients are too often blamed when prescribed treatment is not followed in spite of the evidence that health-care providers and health systems can greatly influence patients' adherence behaviour.

"Health professionals witness the need for better patients' adherence to the treatments they are prescribed. Given that the health care system is partially at fault, incentives must be created to reinforce the efforts of all health professionals in favour of adherence," said Dr Rafael Bengoa, Director, Management of Noncommunicable Diseases, WHO.

At present, there is no doubt that health care teams are failing to provide behavioural support to patients; they are generally not trained to do so. Moreover, health systems do not enable health professionals to support patients’ behavioural change; they have not been designed for it.

The report was developed using a wide variety of chronic conditions and risk factors and looked for their commonalities. Lessons from those diseases with greater experience on adherence interventions, such as hypertension (high blood pressure), asthma, diabetes, and tuberculosis (Directly Observed Treatment Short Course or DOTS), served as a guide to explore many others of which very little is known, such as cancer, depression, epilepsy, HIV/AIDS and tobacco smoking.

Improving adherence may well result in better health outcomes than making available new technologies. An investment that pays, better adherence will avoid excess costs to already stretched health systems and will improve the lives of people with chronic diseases.

For more information contact:

Ms Melinda Henry
Telephone: +41 (22) 791 2535
Mobile phone: +41 (79) 477 1738
Fax: +41 (22) 791 4858
E-mail: henrym@who.int