Research

Prospective analysis of the medicine possession ratio of antidepressants in the private health sector of South Africa, 2006 - 2011

Francois Naude Slabbert, Brian H Harvey, Christiaan Beyers Brink, Martha Susanne Lubbe

Abstract


Background. Major depressive disorder (MDD) is a disabling mental illness with high morbidity and mortality rates. Inadequate treatment efficacy, unfavourable side-effect profiles and consequent shortfalls in compliance are major stumbling blocks in its treatment. Non-compliance data in low- to middle-income countries are lacking.

Objective. To investigate the prevalence of antidepressant (AD) non-compliance in the private healthcare sector of South Africa (SA).

Methods. We conducted a prospective cohort study analysing AD medicine claims (N=35 175) for 14 135 patients, obtained from a nationally representative pharmaceutical benefit management company, over a 6-year study period (1 January 2006 - 31 December 2011). The medicine possession ratio (MPR) was used as a proxy to determine compliance with AD medication. Only patients >18 years of age whose treatment had been initiated by a psychiatrist following an appropriate International Classification of Diseases (10th edition) (ICD-10) diagnosis of a mood disorder were included. A patient was considered compliant if the MPR was between ≥80% and ≤110% over a >4-month treatment period.

Results. After the first 4 months, only 34% of patients were compliant. A statistically significant association was found between active ingredient consumed and compliance (p<0.0001). Only 26.2% of patients who received amitriptyline-containing products were compliant, compared with 38.8% and 38.7% for venlafaxine and duloxetine, respectively.

Conclusion. Compliance data collected from pharmacy claims provide a workable estimate of the broader clinical scenario they represent. Although differences between classes of AD were evident, non-compliance was found to be high in the private healthcare environment of SA, comparable with global trends.


Authors' affiliations

Francois Naude Slabbert, Medicine Usage in South Africa (MUSA), School of Pharmacy, Faculty of Health Sciences, North-West University, Potchefstroom, North West, South Africa

Brian H Harvey, Centre of Excellence for Pharmaceutical Sciences, School of Pharmacy, Faculty of Health Sciences, North-West University, Potchefstroom, North West, South Africa

Christiaan Beyers Brink, Division of Pharmacology, School of Pharmacy, Faculty of Health Sciences, North-West University, Potchefstroom, North West, South Africa

Martha Susanne Lubbe, Medicine Usage in South Africa (MUSA), School of Pharmacy, Faculty of Health Sciences, North-West University, Potchefstroom, North West, South Africa

Full Text

PDF (153KB)

Keywords

Pharmacoepidemiology; Antidepressants; Compliance; Medicine possession ratio; Major depressive disorder; South Africa

Cite this article

South African Medical Journal 2015;105(2):139-144. DOI:10.7196/SAMJ.8394

Article History

Date submitted: 2014-04-29
Date published: 2015-01-05

Article Views

Abstract views: 1369
Full text views: 577

Comments on this article

*Read our policy for posting comments here