Direct medical costs in the preceding, event and subsequent years of first severe hypoglycaemia requiring hospital transfer: A population-based cohort study

Aims To estimate healthcare services use and the direct medical costs accrued by patients with diabetes mellitus (DM) in the year of first severe hypoglycaemia (SH), the years before and after event year.

Materials and Methods We analyzed a population‐based, retrospective cohort including all DM adults managed in primary care setting from the Hong Kong Hospital Authority between 2006‐2013. DM patients who had first recorded SH during the observation period were identified, and matched to control group of patients without SH based on the propensity score method. Direct medical costs in the years before, during and after the first SH were determined by summing up the costs of health services utilized within respective year.

Results After matching, a total of 22,694 DM patients was identified in first recorded SH group (n=11,347) and non‐SH control group (n=11,347). Patients with first SH on average utilized 7.85 outpatient clinic visits, 1.89 emergency visits and 17.75 nights of hospitalization in the event year. Mean direct medical cost in the event year was US$11,751, more than twofold of that in the preceding year (US$4,846, p<0.001) and subsequent years (US$4,198‐4,700, p<0.001), and 4.5 times of that in two years before the event (US$2,481, p<0.001). Incremental costs of SH versus matched control in the event year and preceding year were US$10,873 (p<0.001) and US$3,974 (p<0.001), respectively.

Conclusions SH is associated with excessive hospitalization admission rates and direct medical costs in the event year and, in particular, in the year before as compared to patients without SH.