To explore the interaction between family history of diabetes and sleep duration on prevalence of type 2 diabetes mellitus (T2DM).

A cohort study was conducted among permanent residents aged from 18 to 75 years in Xuzhou in May 2013. On the basis of this, a followed–up study of five years was conducted among a collection of participants without T2DM, and the interaction between family history of diabetes and sleep duration on prevalence of T2DM in followed–up participants was evaluated. Non–conditional logistic regression analysis was used to analyse the association between family history of diabetes and sleep duration on prevalence of T2DM.

Total of 15 939 participants were involved inthe followed–up study, and after five years, finally 11 842 participants were still in the cohort. The average sleep duration of total participants was (7.2±1.1) hours per night. The accumulative rate of T2DM among the followed- up participants was 3.10%. After adjusting for the confounding factors, compared with that participants with sleep duration of 6–8 h/night, individuals with sleep duration<6 hours per night had a higher prevalence of T2DM (RR=1.54,95% CI: 1.21–2.13, P<0.01), and the risk of T2DM did not increase in individuals with sleep duration>8 hours per night (RR=1.31,95% CI: 0.96–1.74, P>0.05). Individuals with family history of diabetes were more likely to suffer from T2DM than those without(RR=4.35,95% CI:2.01- 7.14, P<0.01). After adjusted for potential confounding factors, individuals withfamily history of diabetes and sleep duration <6 hours per night had significantly increased risk prevalence of T2DM (RR=7.98,95% CI: 3.86–12.95, P<0.01) and the risk of T2DM in participants with the family history of diabetesand sleep duration>8 hours per night didn't increase significantly(RR=1.12,95% CI: 0.88 – 1.59, P>0.05) when compared with participants with sleep duration of 6- 8 hours per night without family history of diabetes. After adjusted for potential confounding factors, values of the relative excess risk of interaction (RERI),the attributable proportion(AP), and the synergy index(S) for the additive interaction betweenthe family history of diabetes and sleep duration<6 hours per night were 3.51(1.41- 6.77), 0.46(0.26-0.62) and 1.98(1.24-3.13) respectively, while 0.07(- 0.18-0.31)、0.02(- 0.15-0.10)and 0.95(- 0.04-2.01) for the additive interaction between the family history of diabetes and sleep duration>8 hours per night.

Additive interactions exist between family history of diabetes and sleep duration<6 hours per night. There is not combined interaction to the increased risk of T2DM when family history of diabetes and sleep duration>8 hours per night at the same time.

Diabetes mellitus, type 2; Family history; Sleep duration; Interaction