Interventions to promote deprescribing are an important focus of research. Key decisions for such interventions are whether to target one or multiple medicines, and whether the intervention scope is deprescribing, or also extends to other aspects of medicines optimisation. This article reflects on how these decisions impact on developing interventions and measuring outcomes. Many behavioural strategies are common to deprescribing and medicines optimisation, however operationalisation may differ. Aspects to consider include the burden of multiple simple interventions versus one complex intervention, the extent to which the approach to deprescribing can be specified as part of the intervention, and variability in how the intervention is delivered across patients and providers. Outcomes should be selected based on the intervention target and scope and the audience for whom evidence is being produced. These may include medication changes, and process outcomes to assess intervention delivery. Targeting single medications may allow for a focus on specific clinical or symptom-related outcomes, rather than more general outcomes such as adverse drug reactions. Cost-related outcomes are also important to inform implementation decisions, and modelling approaches may be more feasible for interventions targeting single medications.

Background There is evidence gastrointestinal (GI) motility may play a role in the development of GI cancers. Weak opioids (codeine and dihydrocodeine) decrease GI motility, but their effect on GI cancer risk has not been assessed. Aim To assess the association between weak opioids and cancers of the GI tract. Methods A series of nested case-control studies was conducted using Scottish general practice records from the Primary Care Clinical Informatics Unit Research database. Oesophageal (n=2,432), gastric (n=1,443), and colorectal cancer (n=8,750) cases, diagnosed between 1999 and 2011, were identified and matched with up to five controls. Weak opioid use was identified from prescribing records. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using conditional logistic regression, adjusting for relevant comorbidities and medication use. Results There was no association between weak opioids and colorectal cancer (adjusted OR=0.96, CI 0.90, 1.02, p=0.15). There was an increased risk of oesophageal (adjusted OR=1.16, CI 1.04, 1.29, p=0.01) and gastric cancer (adjusted OR=1.26, CI 1.10, 1.45, p=0.001). The associations for oesophageal cancer, but not gastric cancer, were attenuated when weak opioid users were compared with users of another analgesic (adjusted OR=1.03 CI 0.86, 1.22, p=0.76 and adjusted OR=1.29 CI 1.02, 1.64, p=0.04 respectively). Conclusion In this large population-based study, there was no consistent evidence of an association between weak opioids and oesophageal or colorectal cancer risk, but a small increased risk of gastric cancer. Further investigation is required to determine whether this association is causal or reflects residual confounding or confounding by indication.