Polypharmacy and drug-drug interactions among older and younger male prisoners in Switzerland

• Date: 29 August 2019
• Published date: 29 August 2019
• DOI: https://doi.org/10.1108/IJPH-07-2018-0040
• Pages: 250-261
• Author: Beatrice Annaheim,Tenzin Wangmo,Wiebke Bretschneider,Violet Handtke,Bernice S. Elger,Angelo Belardi,Andrea H. Meyer,Raphael Hösli,Monika Lutters
• Subject Matter: Health & social care,Criminology & forensic psychology,Prisoner health,Sociology,Sociology of crime & law,Public policy & environmental management,Policing,Criminal justice

Polypharmacy and drug-drug interactions

among older and younger male prisoners

in Switzerland

Beatrice Annaheim, Tenzin Wangmo, Wiebke Bretschneider, Violet Handtke, Bernice S. Elger,

Angelo Belardi, Andrea H. Meyer, Raphael Hösli and Monika Lutters

Abstract

Purpose –The purpose of this paper is to determine the prevalence of polypharmacy and drug–drug

interactions (DDIs) in older and younger prisoners, and compared if age group is associated with risks of

polypharmacy and DDIs.

Design/methodology/approach –For 380 prisoners from Switzerland (190 were 49 years and younger;

190 were 50 years and older), data concerning their medication use were gathered. MediQ identified if

interactions of two or more substances could lead to potentially adverse DDI. Data were analysed using

descriptive statistics and generalised linear mixed models.

Findings –On average, older prisoners took 3.8 medications, while younger prisoners took 2.1 medications.

Number of medications taken on one reference day was higher by a factor of 2.4 for older prisoners when

compared to younger prisoners (p ¼0.002). The odds of polypharmacy was significantly higher for older

than for younger prisoners (W¼5 medications: odds ratio ¼5.52, p ¼0.035). Age group analysis

indicated that for potentially adverse DDI there was no significant difference (odds ratio ¼0.94; p ¼0.879).

However, when controlling for the number of medication, the risk of adverse DDI was higher in younger than

older prisoners, but the result was not significant.

Originality/value –Older prisoners are at a higher risk of polypharmacy but their risk for potentially adverse

DDI is not significantly different from that of younger prisoners. Special clinical attention must be given to older

prisoners who are at risk for polypharmacy. Careful medication management is also important for younger

prisoners who are at risk of very complex drug therapies.

Keywords Prison, Elderly prisoners, Polypharmacy, Drug–drug interactions, Older prisoners,

Polymedication

Paper type Research paper

Introduction

Polypharmacy or polymedication literally means the use of more than one drug at any time. In the

literature, it frequently denotes the concurrent use of five or more drugs (Jokanovic et al., 2015;

Masnoon et al., 2017; Mosshammer et al., 2016; WHO, 2018). Polypharmacy is sometimes

also negatively connoted as the inappropriate use of multiple medications or as the use of

medications that are not clinically indicated (Fulton and Allen, 2005; Jokanovic et al., 2015).

To date, there is neither an agreed-upon definition of polypharmacy nor a cut-off point regarding

the number of medications involved (Masnoon et al., 2017). However, it is accepted that there

are certain risks associated with polypharmacy. For instance, polypharmacy increases the risk of

adverse drug reactions and decreases drug compliance (Hajjar et al., 2007; Shah and Hajjar,

2012). In the elderly population, it is associated with inappropriate prescribing, functional decline

and an increased risk for geriatric syndromes (Hajjar et al., 2007; Maher et al., 2014; Shah and

Hajjar, 2012). Polypharmacy also increases the risk of drug–drug interactions (DDIs) (Hajjar et al.,

2007; Maher et al., 2014). DDI is a situation in which one drug modifies the effect of another when

Received 2 July 2018

Revised 29 October 2018

Accepted 29 October 2018

Ethics approval and consent to

participate: ten cantonal ethics

committees approved this study

(EKBB Basel, Bern, Aargau,

Luzern, St Gallen, Valais, Vaud,

Fribourg, Zurich and Thurgau); EK

184/11. Anonymous data were

collected from medical records

requiring no consent from data

subjects. The authors

acknowledge the financial support

of the Swiss National Science

Foundation (SNSF) as well as the

OPO Stiftung. The authors declare

that they have no competing

interests. The authors would like to

thank the team of MediQ for their

support. The authors are grateful

to participating prisons that

provided us access to the data

and the many assistants for

supporting us with data entry and

data checking.

(Information about the authors

can be found at the end of

this article.)

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INTERNATIONALJOURNAL OF PRISONER HEALTH

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VOL. 15 NO. 3 2019, pp. 250-261, ©Emerald Publishing Limited, ISSN 1744-9200 DOI 10.1108/IJPH-07-2018-0040