Background and Aims
Chronic kidney disease (CKD) is a frequent complication to diabetes. CKD is associated with significantly increased risk of morbidity and mortality among people with diabetes. It is well known that the incidence and progression of CKD differ between men and women. Women are more likely to get CKD, while men have a more rapid progression of the disease. However, previous studies were based on small populations. We aimed to investigate the mortality with and without CKD in men and women with type 2 diabetes (T2D).

Method
Secular and age trends in mortality rates and sex differences were investigated in a dynamic, nationwide cohort of people with T2D. CKD was defined based on hospital diagnosis, procedure codes and laboratory measurements. Mortality rates were modelled as an age-period-cohort model using Poisson models with log person time, smooth effects of current age, and calendar time (date of follow-up), separate for each sex and CKD status.

Results
The study included 304,956 persons (55,9% men) and 1,2 million person-years. 87,696 persons were recorded with CKD, of which 34,967 persons had a CKD event during follow-up. The overall mortality rate was 37.8 [37.4; 38.2] versus 31.1 [30.4; 31.7] per 1000 person-years for people with T2D, without and with CKD, respectively. The mortality rate for people with T2D and CKD is larger and more pronounced in the younger ages. For elderly people the mortality rate is larger for people with T2D and without CKD. In general, mortality for men is higher than mortality for women at all ages, observed for both people with and without CKD. The overall secular trend per year was increasing for persons without CKD 2.0 [1.8; 2.2] %/year. For those with CKD, a decrease −2.4 [−2.1; −2.6] %/year was observed, decreasing until start 2017 followed by an increase. The overall M/F mortality ratios were 1.23 [1.20; 1.25] and 1.91 [1.83; 2.00], respectively.

Conclusion
The observed larger and more pronounced mortality rate for people with T2D and CKD in the younger ages, suggests a potential for early preventive intervention among young adults. Supported by an unrestricted grant from Bayer.