Adherence
Definitions
Adherence is the extent to which a person’s behaviour – taking medication, following a diet, and/or executing lifestyle changes – corresponds with agreed recommendations from healthcare providers (1). Therapeutic adherence is a summary term determined by persistence and compliance of medication intake.
Compliance can be defined as the extent to which a person follows medical advice relating to dose and dosing interval.
Persistence refers to the length of time a patient continues taking medication and is measured as the time from treatment initiation to treatment discontinuation.
Long-term therapies and adherence
Poor adherence with medications used to treat chronic conditions is a common phenomenon, even more critical when the disease is asymptomatic, when treatment does not provide a benefit which is immediately perceived by the patient and/or generates adverse reactions. This issue has been considered as a critical hurdle to treatment success and remains an important challenge to healthcare professionals (1). Recently, a meta-analysis of 21 observational studies in various
chronic diseases, such as cardiovascular diseases, HIV or diabetes, demonstrated that good adherence to beneficial treatment is associated with lower mortality (OR=0.56, CI 95%: 0.50-0.63) (2).
Osteoporosis is typically a chronic, asymptomatic condition requiring long-term treatment. However, even when diagnosed, osteoporotic patients do not usually perceive any clinical benefit from taking their medications, in the absence of extemporaneous measurement of their
condition (3,4).
A recent study concluded that approximately 50-75% of women who initiate any type of anti-osteoporosis drug therapy (bisphosphonates, calcitonin, HRT, SERM) are no longer persistent 12 months after initiation of the treatment (5).
Impact of poor adherence in osteoporotic patients
Compared to patients who adhere to their drug therapy, patients with inadequate adherence present with:
- Smaller increases in bone mineral density (BMD) (6)
- Weaker suppression of bone resorption (for antiresorptive agents) (7)
- Less decrease in fracture risk (8)
Determinants of poor adherence
Poor adherence to long term treatment is of multifactorial origin and many determinants have been identified (9):
Disease related
- Multiple co-morbidities
- Absence of symptoms
- Long-term therapy required
- No immediate advantage perceived from therapy
Drug related
- Costs
- Adverse effects
- Access to treatment
- Duration of treatment
- Frequency of administration
- Complexity of regimen: impact on quality-of-life
- Prevention vs. treatment
- Greater number of drugs
Emotive/patient related
- Denial of illness
- Lack of social support
- Lack of disease knowledge
- Disruption to lifestyle or inconvenience
- Patients’ own views about how they are best treated
- Patients’ concerns about the value or appropriateness of taking medicines
- Confusion or physical difficulties associated with taking medicines
Follow-up
- Time
- Cost
- Difficulties to follow-up
Others
- Patient-physician relationship
Proposals to overcome adherence issues
Health professional-patient relationship
- Improve communication between physician and patient
- Provide appropriate education
- Pharmacists to provide advice on treatment
Treatment setting (10)
- Choose simple dosing regimen that fits with patient’s lifestyle
- Choose treatment according to patient’s preference
Follow-up
- Monitor adherence and react promptly if poor compliance or lack of persistence is identified.
- Physician to provide frequent positive feedback (Use of biochemical markers of bone turnover(12) or BMD measurements to illustrate beneficial response to treatment)
- Self management programs (11)
References
- World Health organisation. Prevention and management of osteoporosis. World Health Organ Tech Rep Ser 2003;921:1-164
- Simpson AH, Eurich DT, Majumdar SR, Rajdeep SP, Tsuyuki RT, Varney J, Johnson JA. A meta-analysis of the association between adherence to drug therapy and mortality. BMJ 2006;333:15-20
- Reginster JY. Adherence and persistence: impact on outcomes and health care resources. Bone 2006;38:S18-21
- Reginster JY, Rabenda V, Neuprez A. Adherence, patient preference and dosing frequency: Understanding the relationship. Bone 2006;38:S2-6
- Weycker D, Macarios D, Edelsberg J, Oster G. Compliance with drug therapy for postmenopausal osteoporosis. Osteoporosis Int 2006;
- Toteston AN, Grove MR, Hammond CS, Moncur MM, Ray GT, Hebert GM, Pressman AR, Ettinger B. Early discontinuation of treatment for osteoporosis. Am J Med 2003 15;115:209-16
- Sebaldt RJ, Shane LG, Pham B, Cook R, Thabane L, Petrie A,…. Long-term effectiveness outcomes of non-compliance and non-persistence with daily regimen bisphoshonate therapy in patients with osteoporosis treated in tertiary specialist care. Osteoporosis Int 2004;15:S107 [Abstract P391SA]
- Eastell R, Garnero P, Vrijens L, Van de Langerijt L, Pols HAP, Ringe JD, … Influence of patient compliance with risedronate therapy on bone turnover marker and bone mineral density response: The IMPACT study. Calcif Tissue Int 2003;72:408 [Abstract P297]
- Sambrook P. Compliance with treatment in osteoporosis patients: An ongoing problem. Aust Fam Physician 2006;35:135-7
- Siris E, Rosen CJ, Harris ST, Abbott T, Barr CE, Silverman S. Adherence to bisphosphonate therapy: Relationship to bone fractures at 24 months in women with postmenopausal osteoporosis. Poster presented at NOF Sixth International Symposium on Osteoporosis 2005 [7April]
- Gold DT, McClung B. Approaches to patient education: emphasizing the long-term value of compliance and persistence. Am J Med. 2006;119:S32-7
- Delmas PD, Vrijens B, Roux C, Le-Moigne-Amrani A,. Eastell R, Grauer A, Watts NB, Pols HA, Ringe JD, Cahall D. A Reinforcement Message Based on Bone Turnover Marker Response Influences Long-Term Persistence with Risedronate in Osteoporosis: The IMPACT Study.. ASBMR 2003 [Poster M330]
