The effects of hypoglycemia and dementia on cardiovascular events, falls and fractures and all-cause mortality in older people: a retrospective cohort study

Aims: Older people with diabetes are susceptible to harm from hypoglycemia, however the consequences of hypoglycemia in older people with dementia are not known. We aimed to test association between hypoglycemia and serious adverse events in older patients with diabetes and dementia, and whether the consequences of hypoglycemia were affected by presence of dementia. 
Materials and Methods: Cohort study using Clinical Practice Research Datalink in England (1997-2016). We selected participants, intervention (exposure) and follow-up to mirror two hypothetical target randomised controlled trials. Target trial 1’s exposure was hypoglycemia in patients with dementia. Target trial 2 examined adverse effects of hypoglycemia according to dementia status.We used Cox proportional hazard regression to estimate adjusted hazard ratios (aHR) for falls, fractures, cardiovascular events and mortality. 
Results: In target trial 1, hypoglycemia was associated with an increased risk during 12 months follow-up of falls and fractures - aHR 1.94 (95% CI 1.67 to 2.24), cardiovascular events - aHR 2.00 (95% CI 1.61 to 2.48) and mortality - aHR 2.36 (95% CI 2.09 to 2.67).In target trial 2, presence of dementia was associated with increased risk of adverse events after hypoglycemia (12 months follow-up): falls & factures - aHR 1.72 (95% CI 1.51 to 1.96) and mortality - aHR 1.27 (95% CI 1.15 to 1.41), but had no effect on cardiovascular events - aHR 1.14 (95% CI 0.95 to 1.36). 
Conclusions and Relevance: Hypoglycemia is associated with an early increased risk of serious adverse events in older people with diabetes and dementia.