by Izzati Yussof, Nor Asyikin Mohd Tahir, Ernieda Hatah,
Noraida Mohamed Shah
This systematic review aimed to determine the rate and
identify correlates of adherence and persistence over five years of treatment
with adjuvant endocrine therapy in female breast cancer patients.
Methods
Relevant articles were identified from Medline, Embase,
AMED, PsycINFO, International Pharmaceutical Abstracts, and APA PsycArticles.
Studies that measured patient adherence in the implementation or persistence
phase for a period of at least five years using objective or multiple measures
of adherence and investigated correlates of adherence were included. The
titles, abstracts and full articles were screened and reviewed by two authors
and any discrepancies were discussed with a third author.
Results
Twenty-six studies were included. Mean rate of adherence at
five-year for implementation phase was 66.2% (SD = 17.3%), and mean
persistence was 66.8% (SD = 14.5%). On average, adherence decreased
by 25.5% (SD = 9.3%) from the first to fifth year. Higher rate of
adherence was observed through self-report in comparison to database or medical
record. Older age, younger age, higher comorbidity index, depression and
adverse effects were associated with lower adherence. Treatment with aromatase
inhibitors, received chemotherapy, and prior medication use were associated
with improved adherence.
Conclusion
Adherence to adjuvant endocrine therapy decreased from the
first to fifth year of treatment. On average, one-third of patients were not
adherent to treatment by the fifth year. Nineteen recurring factors were found
to be significantly associated with long-term adherence in multiple studies.
Further research using objective or multiple measures of adherence are needed
to improve validity of results.
