Low-carb diets up death risk in CKD

Adults with chronic kidney disease (CKD) may see excess mortality risk if they keep a low-carbohydrate diet (LCD), reports a recent study. Such an effect is absent in adults without CKD.

Accessing the Third National Health and Nutrition Examination Survey, researchers assessed the diets of 1,158 adult CKD patients and 9,523 controls without CKD. An LCD score was calculated using a 24-hour dietary recall interview, while mortality was monitored from baseline until 31 December 2015.

Participants were stratified according to quartiles of the LCD score. In the CKD group, the highest and lowest LCD quartiles had a mean daily carbohydrate intake of 61.9 percent and 37.9 percent of the total energy intake, respectively. In non-CKD controls, the corresponding mean values were 61.4 percent and 37.6 percent.

Over a median follow-up of 24 years, 751 all-cause deaths were reported in the CKD group, yielding a mortality rate of 65 percent. In comparison, 2,624 deaths in the non-CKD group corresponded to a 28-percent mortality rate.

Multivariable Cox regression analysis revealed that in adults with CKD, those in the top vs bottom quartiles of LCD score were significantly more likely to die of all causes (hazard ratio [HR], 1.51, 95 percent confidence interval [CI], 1.01–2.24; p_trend=0.045). A similar effect was reported for the second (HR, 1.32) and third (HR, 1.31) quartiles, though statistical significance was not reached.

In non-CKD controls, the second (HR, 1.16), third (HR, 1.01), and fourth (HR, 1.08) quartiles of LCD score had statistically comparable all-cause mortality risks as compared with the bottom quartile (p_trend=0.657).