Association between serum chloride levels with mortality in incident peritoneal dialysis patients

L-shaped association between serum chloride levels with 90-day and 365-day all-cause mortality in critically ill patients with COPD: a retrospective cohort study

This study aimed to investigate the association between serum chloride levels and all-cause mortality in critically ill patients with chronic obstructive pulmonary disease (COPD). Data from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database were extracted for analysis. Demographic information, laboratory results, medical histories, vital signs, and prognosis-related data were collected. Cox proportional hazard models were used to assess the relationship between serum chloride levels and 90-day and 365-day mortality. Subgroup analyses were conducted to explore potential interactions between serum chloride levels and various factors. The study included patients with a median age of 72.00 years, of whom 52.39% were male. Higher quartiles of serum chloride levels were associated with significantly lower levels of weight, RBC, platelet, hemoglobin, and other variables (P < 0.05), accompanied by lower 90-day and 365-day mortality (P < 0.05). Cox proportional hazard model indicated that the risk of death was significantly lower in the fourth quartile of serum chloride levels compared with the first quartile after adjusting for confounders (90-day HR = 0.54, 365-day HR = 0.52, both P < 0.05). An L-shape relationship was observed, with risks of death decreasing as serum chloride levels increased, although the magnitude decreased when levels reached 102 mmol/L. This study demonstrated an independent L-shaped association between serum chloride levels and all-cause mortality in critically ill patients with COPD. This finding helps us to understand the prognostic value of serum chloride levels in critically ill patients with COPD.

Serum chloride as a marker of cardiovascular and all-cause mortality in chronic hemodialysis patients: 5-Year follow-up study

BACKGROUND

Hypochloremia has been associated with increased mortality in patients with hypertension, heart failure, sepsis, and chronic kidney disease (CKD). The pathophysiological mechanisms of this finding are not clear. There are no studies describing an association between serum chloride levels (Cl-) and mortality in incident chronic hemodialysis (HD) patients.

METHOD

Retrospective cohort study of the incident population in our chronic outpatient hemodialysis program between January 1, 2016, and January 1, 2021 (N=374). Survival time was collected in all patients and analyzed using the Kaplan-Meyer method. A multivariate Cox regression model was performed to predict the probability of survival, applying a stepwise procedure.

RESULTS

During the median follow-up period of 20 months, 83 patients died. The 5-year overall survival rate for our patients was 45%. Both natremia and chloremia had no significant differences when compared by sex, vascular access, or etiology. There was an inverse correlation between Cl- and interdialytic weight gain (r=-0.15) (p=0.0038). Patients belonging to the quartile with lower Cl- levels had less probability of survival than patients in the quartile with higher Cl- levels (27% and 68%, respectively, p=0.019). On the other hand, in the multivariate Cox regression model, variables significantly associated with higher mortality were being older, having higher baseline comorbidity by modified Charlson index, not taking diuretics and having lower albumin and chloride levels. Particularly, higher Cl- levels was independently associated with both lower all-cause mortality (adjusted hazard ratio [HR]=0.84; 95% confidence interval [CI], 0.77-0.92; p=0.0001) and cardiovascular mortality (HR 0.9; 95% CI, 0.83-0.97; p<0.0057).

CONCLUSIONS

Lower Cl- levels were associated with higher all-cause and cardiovascular mortality in incident patients on chronic hemodialysis in our health area.