Aims: The association between recent and more distant weight changes before and after the diagnosis of type 2 diabetes has been little researched. The aim of this study is to determine the influence of patients’ weight history before diabetes diagnosis on the observed 6-year weight changes after diagnosis.

Methods: A clinical cohort study combined with self-reported past weight history. In total 885 patients aged ≥40 years and newly diagnosed with clinical type 2 diabetes were included. Body weight was measured immediately after diabetes diagnosis and again at the 6-year follow up examination (median, 5.7 years). At diagnosis patients reported their weight 1 year and 10 years previously, and also at the age of 20. Multivariate linear regression analyses controlled for 20 baseline patient characteristics.

Results: The median (interquartile range) age at diagnosis was 63.2 (53.9; 71.4) years. Median body weight was 80.0 (72.0; 90.0) kg 10 years before diagnosis, 85.0 (75.0; 95.0) kg 1 year before diagnosis, 82.4 (72.0; 94.0) kg at diagnosis, and 80.0 (70.0; 91.1) kg at 6-year follow up. Each kg of weight gain during the year preceding the diagnosis was associated with a weight change (95% CI) of -0.20 (-0.28; -0.13) kg during the follow up period. In all models age and body mass index at diagnosis predicted future weight changes, while the weight at age 20 (-0.01 (-0.06; 0.03) kg/kg), and the weight change from 10 years to 1 year before diagnosis (-0.01 (-0.06; 0.04) kg/kg), did not predict weight change after diagnosis.

Conclusions: During the first on average 5.7 years after diagnosis of type 2 diabetes, patients generally follow a course of declining average weight, and these weight developments are related primarily to recent weight changes, body mass index, and age, but not to the more distant weight history.