Evaluation of medication compliance in patients on antidepressants at an outpatient tertiary cancer center setting

Abstract

Objective. The purpose is to evaluate antidepressant compliance in a cancer population at a tertiary cancer center and to determine if there are covariates of importance in predicting the level of compliance in the study population.

Methods. Patients who received at least three prescriptions covering parts of each month for a continuous 6-month period with at least one of the months being in 2006 from a tertiary cancer center were identified as the prevalent population of interest for this retrospective study. Data collected included demographics, cancer and co-morbid diagnoses, and compliance to antidepressant medication using medication possession ratio (MPR) by patient, medication class, and individual agents. Analysis was conducted using descriptive statistics, analysis of variance, and logistic regression (using MPR ≥ 80 as cutoff).

Results. The study population included 297 patients with demographics showing 69% female, 71% Caucasian, a mean age of 52.94 (SD: 12.42), and an average 403 days of follow-up. The MPR for the total study population was 0.87 with 78% of the population having an MPR of ≥80% and 22% having an MPR of less than 80%. While there was no significant difference in MPR by different pharmaceutical classes, there were significant differences in the MPR by specific agents (p = 0.02), with nortriptyline having the lowest MPR of 0.79 and doxepin, fluoxetine, mirtazapine, and venlafaxine all having MPR over 0.90. There was also a trend toward a difference in MPR between Caucasians versus non-Caucasians, p = 0.055.

Conclusion. There appears to be relatively good compliance to antidepressant medications in the study population.

Keywords

compliance medication procession ratio antidepressant usage cancer

Get full access to this article

View all access options for this article.

References

Haynes RB , Taylor DW , Sackett DL , eds. Compliance in health care. Baltimore: John Hopkins University Press, 1979.

Hess LM , Raebel MA , Conner DA , Malone DC Measurement of adherence in pharmacy administrative databases: a proposal for standard definitions and preferred measures. Ann Pharmacother 2006; 40: 1280-8.

Masand PS , Roca M. , Turner MS , Kane JM Partial adherence to antipsychotic medication impacts the course of illness in patients with schizophrenia: a review. Prim Care Companion J Clin Psychiatry 2009; 11(4): 147-54.

Vestbo J. , Anderson JA , Calverley PM , Celli B. , Ferguson GT , Jenkins C. et al. Adherence to inhaled therapy, mortality, and hospital admission in COPD. Thorax 2009; 64(11): 939-43.

Ziller V. , Kalder M. , Abert US , Holzhauer W. , Ziller M. , Wagner U. et al. Adherence to adjuvant endocrine therapy in postmenopausal women with breast cancer. Ann Oncol 2009; 20(3): 431-6.

Ruddy K. , Mayer E. , Patridge A. Patient adherence and persistence with oral anticancer treatment. CA Cancer J Clin 2009; 59(1): 56-66.

Patridge AH , Avorn J. , Wang PS , Winer EP Adherence to therapy with oral antineoplastic agents. J Natl Cancer Inst 2002; 94: 652-61.

Valeberg BT , Miaskowski C. , Hanestad BR , Bjordal K. , Moum T. , Rustoen T. et al. Prevalence rates for and predictors of self-reported adherence of oncology outpatients with analgesic medications. Clin J Pain 2008; 24: 627-36.

Kirk MC , Hudis CA Insight into barriers against optimal adherence to oral hormonal therapy in women with breast cancer. Clin Breast Cancer 2008; 8(2): 155-61.

10.

Watson M. , Haviland JS , Greer S. , Davidson J. , Bliss JM Influence of psychological response on survival in breast cancer: a population-based cohort study. Lancet 1999; 354: 1331-6.

11.

Prieto JM , Atala J. , Blanch J. , Carreras E. , Rovira M. , Cirera E. et al. Role of depression as a predictor of mortality among cancer patients after stem-cell transplantation. J Clin Oncol 2005; 23: 6063-71.