Potentially inappropriate medication prescribing is associated with socioeconomic factors: a spatial analysis in the French Nord-Pas-de-Calais Region

Abstract

Background: potentially inappropriate medication (PIM) prescribing is common in older people and leads to adverse events and hospital admissions.

Objective: to determine whether prevalence of PIM prescribing varies according to healthcare supply and socioeconomic status.

Methods: all prescriptions dispensed at community pharmacies for patients aged 75 and older between 1 January and 31 March 2012 were retrieved from French Health Insurance Information System of the Nord-Pas-de-Calais Region for patients affiliated to the Social Security scheme. PIM was defined according to the French list of Laroche. The geographic distribution of PIM prescribing in this area was analysed using spatial scan statistics.

Results: overall, 65.6% (n = 207,979) of people aged 75 years and over living in the Nord-Pas-de-Calais Region were included. Among them, 32.6% (n = 67,863) received at least one PIM. The spatial analysis identified 16 and 10 clusters of municipalities with a high and a low prevalence of PIM prescribing, respectively. Municipalities with a low prevalence of PIM were characterised by a high socioeconomic status whereas those with a high prevalence of PIM were mainly characterised by a low socioeconomic status, such as a high unemployment rate and low household incomes. Markers of healthcare supply were weakly associated with high or low prevalence clusters.

Conclusion: significant geographic variation in PIM prescribing was observed in the study territory and was mainly associated with socioeconomic factors.

Keywords: inappropriate prescribing; older people; pharmacoepidemiology; scan statistics.