Introduction:

The body mass index is an indicator that is often used to identify overweight and obesity in adults. In the population with chronic kidney disease, observational studies have reported contradictory results regarding the association between obesity and mortality. Also, different authors have observed as those having a body mass index higher, a better nutritional status is showed.

Objective:

To establish a comparative study of subjects according to their body mass index.

Material and Method:

Observational, analytical and longitudinal study. A total of 170 prevalent patients with chronic kidney disease on treatment with hemodialysis or online hemodiafiltration were recruited. The body mass index based on actual weight and size of the patient at the time of data collection was calculated. Patients who died during the follow-up period were recorded.

Results:

The patients who died had a lower body mass index, although the differences were not statistically significant. Patients who met the target body mass index also had higher levels of hydration, a lower rate of fat, and lower blood levels of transferrin, a greater Kt/ve and a greater number of months in renal replacement therapy.

Conclusions:

A body mass index = 25 kg / m² was not associated, in our case, with higher mortality, although a trend in this direction is observed. Patients with body mass index = 25 kg / m² had a better nutritional status.