Introduction As health reforms move Ireland from a mixed public-private system toward universal healthcare, it is important to understand variations in prescribing practice for patients with differing health cover and socioeconomic status. This study aims to determine how prescribing patterns for patients aged ≥65 years in primary care in Ireland differ between patients with public and private health cover.

Methods This was an observational study using anonymised data collected as part of a larger study from 44 general practices in Ireland (2011-2018). Data were extracted from electronic records relating to demographics and prescribing for patients aged ≥65 years. The cohort was divided between those with public health cover (via the General Medical Services (GMS) scheme) and those without. Standardised rates of prescribing were calculated for pre-specified drug classes. We also analysed the number of medications, polypharmacy, and trends over time between groups, using multilevel linear regression adjusting for age and sex.

Results Overall, 42,456 individuals were included (56% female). Most were covered by the GMS scheme (62%, n=26,490). The rate of prescribing in all medication classes was higher for GMS patients compared to non-GMS patients, with the greatest difference in benzodiazepine anxiolytics. The mean number of unique medications prescribed to GMS patients was 10.9 (SD 5.9), and 8.1 (SD 5.8) for non-GMS patients. The number of unique medications prescribed to both GMS and non-GMS cohorts increased over time. The increase was steeper in the GMS group where the mean number of medications prescribed increased by 0.67 medications/year. The rate of increase was 0.13 (95%CI 0.13, 0.14) medications/year lower for non-GMS patients, a statistically significant difference.

Conclusion Our study found a significantly larger number of medicines were prescribed to patients with public health cover, compared to those without. Increasing medication burden and polypharmacy among older adults may be accelerated for those of lower socioeconomic status. These findings may inform planning for moves towards universal health care, and this would provide an opportunity to evaluate the effect of expanding entitlement on prescribing and medicines use.

The authors have declared no competing interest.

This research was funded by the Health Research Board in Ireland (HRB) through an Investigator Led Projects grant (grant number ILP-HSR-2019-006). BC is supported by an Emerging Investigator Award grant from the HRB (grant number EIA-2019-09).

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

Approval was granted by the Irish College of General Practitioners Research Ethics Committee.

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The dataset analysed during the current study is not publicly available as provisions for data sharing were not included in the initial ethical approval.