Background: Complications can be present at type 2 diabetes (T2D) diagnosis or develop later. We describe trends in burden of ischaemic heart disease (IHD) in T2D.
Methods: T2D cases in Denmark 1996-2020 in a national diabetes register were used. Events of IHD 1994-2020 were from the National Patient Register. Prevalence of IHD at time of T2D was described by a binomial model. New IHD and death during follow-up were analysed by rate models and used to estimate the time in the states (no IHD / IHD at T2D / IHD after T2D) .
Results: 410,4 persons with T2D 1996-2020 were included; 61,378 with pre-existing IHD. Prevalence of IHD at T2D diagnosis was increasing 1.7%/year. Incidence rates of IHD after diagnosis was decreasing 5.7%/year. Mortality among T2D persons without IHD decreased 5.7%/year; for those with IHD it decreased 3.5%/year. During the first years, expected lifetime was 8.1 and 8.8 years for men diagnosed at age 65 in 1998 and 2018, respectively. Time without IHD was 6.2 and 6.9 years, with new IHD 0.9 and 0.5 years and with preexisting IHD 1.0 and 1.5 years in 1998 and 2018. We saw an increase in expected lifetime, partly as increase in lifetime with preexisting IHD. Similar patterns were seen for women and for persons diagnosed in other ages.
Conclusions: We saw an increase in expected lifetime, as well as decreasing mortality rates regardless of IHD status. Prevalence of IHD at the time of diagnosis was increasing, possibly due to more detailed diagnoses of IHD; in our data only IHD complications after 1994 are included which may be a partial explanation of the increase in prevalent IHD at the date of T2D diagnosis. In general the IHD burden in T2D in Denmark is decreasing.
B.Carstensen: Stock/Shareholder; Novo Nordisk A/S. K.K.Clemmensen: Employee; Novo Nordisk A/S, Research Support; AstraZeneca, Novo Nordisk Foundation, Stock/Shareholder; Lundbeck, Novo Nordisk A/S. H.Amadid: Stock/Shareholder; Novo Nordisk.