Establishment of a nomogram model and scoring system for kidney stone prediction based on diet and lifestyle

To develop an effective tool for assessing the risk of kidney stones based on people's diet and lifestyle factors. A cross-sectional study was conducted on 6430 people in southern China from February to June 2022, and epidemiological data were collected through questionnaires. Variables with P <.05 in univariate analysis were subjected to least absolute shrinkage and selection regression analysis for predictor selection with nonzero coefficients. We utilized multivariate logistic regression analysis to screen out independent risk factors and then developed a nomogram to assess the risk of kidney stones occurrence. The concordance index (C-index), receiver operating characteristic curve and calibration curve were utilized for internal test the accuracy of nomogram prediction. decision curve analysis was used to evaluate the clinical applicability of nomogram. We further evaluated the risk of kidney stones based on the influence of available variables. Gender, age, daily water intake, main drinking water, primary food types, preferred beverage, body mass index value, daily steps taken and family history were identified as independent risk factors to established the nomogram. The favorable C-index value (0.759; 95% CI = 0.735-0.782), receiver operating characteristic curve (area under the curve value = 0.762) and calibration curves demonstrated the effectiveness of the prediction model. decision curve analysis curve showed the nomogram had positive net benefits across a threshold probability range of 0% to 89%. We further developed a scoring system and classified the risk of kidney stones into 4 grades. Individuals with a higher grade demonstrated an increasing trend in both the risk of kidney stone occurrence and the distribution of larger stone sizes. The established nomogram model and risk scoring system have favorable performance, which may provide lifestyle and dietary recommendations for the early prevention and recurrence reduction of kidney stone.