Weight loss before a diagnosis of type 2 diabetes mellitus is a risk factor for diabetes complications

Our goal was to investigate the relationship between weight loss before a diagnosis of type 2 diabetes mellitus (T2DM) and diabetic complications among hospitalized patients with T2DM. We conducted a cross-sectional study and evaluated 347 and 642 hospitalized patients with T2DM who experienced and did not experienced weight loss before T2DM diagnosis, respectively. We used propensity score matching to reduce the confounding bias between the groups. In addition, a logistic regression analysis of the matched data was performed to evaluate the risk of diabetic complications. A total of 339 patients who experienced weight loss were matched to 339 patients who did not experience weight loss. After adjusting for age, gender, origin, occupation, smoking history, alcohol use, and duration of diabetes, the logistic regression analysis showed that compared with patients who did not experience weight loss, patients who lost ≤5 kg had a higher risk of diabetic nephropathy (DN) (odds ratio [OR]: 2.05, 95% confidence interval [CI]: 1.35–3.10) and diabetic retinopathy (OR: 1.79, 95% CI: 1.11–2.87). However, we did not observe a dose–response relationship in terms of weight loss. We found that weight loss before a diagnosis of T2DM might serve as a risk factor for DN and diabetic retinopathy. Our findings demonstrate that we should strengthen the management and prevention of complications in patients who experience weight loss of ≤5 kg prior to a T2DM diagnosis, particularly those who are centrally obese.