The incidence of childhood type 1 diabetes in Australia forms a regular cyclical pattern over time say researchers who suggest caution over using linear trends to predict future incidence.

Professor Tim Jones and Elizabeth Davis from the Telethon Kids Institute in Western Australia found five-yearly peaks and troughs in incidence trends Australia wide, which corroborated with findings previously reported for Western Australia.

“Interestingly the sinusoidal pattern was observed in both boys and girls and in all age groups suggesting that factors influencing the incidence of type 1 diabetes mellitus in Australia are similar across these subgroups,” they wrote in Diabetologia.

The non-linear temporal trends seen in the study may indicate a role for environmental factors such as viral infection or climatic factors, they said.

There was still much yet to be understood regarding the aetiology, natural history and critical windows in the development of childhood type 1 diabetes.

“Understanding more about the timescale and natural history of diabetes will help researchers identify factors relevant to different phases of the natural history and the likely multiple causal pathways of this complex disease,” they wrote.

In the meantime worldwide population based registers will continue to provide invaluable resources for monitoring incidence, they added.