Smoking status affects bioimpedance-derived phase angle in men but not in women: The Pró-Saúde Study, Brazil.

OBJECTIVE: Phase angle (PhA) is determined by bioelectrical impedance (BIA) and it is interpreted as an index of cell membrane integrity. Smokers are susceptible to systemic oxidative stress and often adopt unhealthy habits, which may contribute to cellular damage. This unfavorable conjuncture may result in lower PhA in smokers. The aim of this study was to investigate the association between PhA and smoking status. METHODS: This cross-sectional study included 247 (48%) adult men. Body composition and PhA were determined using dual-energy x-ray absorptiometry and BIA, respectively. Blood sampling, food habits, and smoking status information were collected. Statistical analyses were performed for each sex separately. Analysis of covariance controlling for body mass index and age compared PhA values across smoking categories. Multiple linear regression determined whether smoking status was a PhA predictor. RESULTS: PhA was lower in male current smokers (6.6 ± 0.13°) compared with never-smokers (7 ± 0.06°; P = 0.038). The ratio of extracellular to intracellular water was higher in current (P = 0.003) and former male smokers (P = 0.006) compared with never-smokers. Body composition did not differ in male and female smoking categories. Male current smokers ingested more calories, protein, carbohydrates, and alcohol than never and former smokers (P < 0.05). Current female smokers had higher alcohol consumption compared with never smokers (P = 0.019). Male current smokers presented lower than never-smokers (unstandardized ß coefficient = -0.202; 95% confidence interval, -0.359 to -0.046). Smoking status was associated with PhA decrease only in men. CONCLUSION: The results from the present study suggest that being a current smoker results in lower PhA in men, even when controlling for other variables.

Performance of subjective global assessment and malnutrition inflammation score for monitoring the nutritional status of older adults on hemodialysis.

BACKGROUND & AIMS: Studies assessing the performance of 7-point subjective global assessment (7p-SGA) and malnutrition inflammation score (MIS) to assess longitudinal changes in nutritional status are lacking. Thus, we aimed to investigate whether longitudinal changes in 7p-SGA and MIS were associated with changes in objective parameters of nutritional status, as well as to evaluate the prognostic value of 7p-SGA and MIS on hospitalization events. METHODS: One hundred and four patients aged ≥60 years (70.2% male, age: 70.9 ± 6.9 years) on maintenance hemodialysis were studied. The 7p-SGA, MIS and objective parameters of nutritional status (anthropometrics, muscle strength, body cell mass and phase angle assessed by bioelectrical impedance analysis - BIA, albumin, creatinine and C-reactive protein) were assessed at baseline and 12 months after the enrollment. Follow-up for hospitalization events were carried out at 13.0 (interquartile range: 3.0; 21.0) months after the first year of enrollment. RESULTS: Analysis of repeated measures, stratified by gender, and adjusted for age and dialysis vintage, showed that for men, a 1-unit change in 7p-SGA was significantly associated (P < 0.05) with changes in all anthropometrics, muscle strength and BIA parameters. For women, changes in 7p-SGA were associated with most of the anthropometrics, muscle strength and BIA parameters. Similarly, for both genders, changes in MIS were associated with changes in most anthropometric, muscle strength, BIA measurements, albumin (only for men), and creatinine (only for women). In addition, when assessed by 7p-SGA, patients with a declining nutritional status had a higher relative risk (RR) of hospitalization events [RR: 2.08 (95 CI: 1.44-2.99; P < 0.001)] and length of hospital stay (days) [RR: 3.73 (95 CI: 3.29-4.22; P < 0.001)]. CONCLUSIONS: Longitudinal changes in 7p-SGA and MIS were associated with changes in most of the objective parameters tested during 12 months of follow-up. Furthermore, a declining 7p-SGA score predicted a greater number of hospitalization events and days of hospital stay.