The impact of NHS England prescription guidance for Clinical Commissioning Groups on prescribing rates of simple analgesia in primary care.

Problem

In the NHS in England in 2017/18, £17.4 billion was spent on pharmaceutical drugs, £8.9 billion of which was from GP prescriptions. In March 2018, as a measure to rationalise and optimise spending, NHS England published guidance for Clinical Commissioning Groups (CCGs) detailing a list of medications that could be bought over the counter and that should in most cases not be prescribed. This included simple analgesia.In this study, we investigate the impact of this guidance on the prescribing rates of simple analgesia in primary care. In addition, we explore whether CCGs have actively implemented this guidance, and whether there is any evidence that the guidance has created a health inequality.

Approach

The simple analgesics included were oral paracetamol; oral ibuprofen and topical non-steroidal anti-inflammatory drugs (NSAIDs). Practice-level prescribing data from January 2015 to March 2019 were obtained from NHS Digital and filtered for simple analgesia by use of their British National Formulary (BNF) codes. Linking the resulting data to quarterly practice list sizes allowed a calculation of monthly prescribing rates across England. Taking the “intervention” time point to be March 2018, an interrupted time series analysis (ITSA) was conducted to assess the effect of the intervention, both with and without an adjustment for seasonality.To explore a potential health inequality, we examined the association between practice-level prescribing rates and deprivation (using the Index of Multiple Deprivation [IMD] score) both 12 months before and 12 months after the intervention, using multivariable Poisson regression, adjusting for sex, proportion of over-65s and practice list size. Freedom of information (FOI) requests were submitted to all CCGs to elicit to what extent each had implemented the NHS England guidance.

Findings

Data analysis is currently underway. Initial results suggest that the intervention was associated with a ~4% reduction in prescribing rate of simple analgesia overall (adjusted incidence rate ratio [aIRR] 0.956, p < 0.001) after accounting for an underlying time trend and seasonality. Practice-level prescribing rates were significantly associated with IMD score, although the strength of this association was similar before and after the intervention (aIRR 2.44 [95% CI 2.33-2.57] pre-intervention and 2.42 [95% CI 2.30-2.56] post-intervention). All 195 CCGs responded to the FOI request. The results of these will be presented, along with ITSA analyses of individual simple analgesics.

Consequences

The results so far suggest that the NHS England guidance has resulted in a reduction in the prescribing of simple analgesia, without creating an additional health inequality. The value of varying strengths of implementation by CCGs requires exploration.