Inverse relationship between body mass index and mortality in older nursing home residents: a meta-analysis of 19,538 elderly subjects

Body mass index (BMI) and mortality in old adults from the general population have been related in a U-shaped or J-shaped curve. However, limited information is available for elderly nursing home populations, particularly about specific cause of death. A systematic PubMed/EMBASE/CINAHL/SCOPUS search until 31 May 2014 without language restrictions was conducted. As no published study reported mortality in standard BMI groups (<18.5, 18.5-24.9, 25-29.9, ≥30 kg/m(2)), the most adjusted hazard ratios (HRs) according to a pre-defined list of covariates were obtained from authors and pooled by random-effect model across each BMI category. Out of 342 hits, 20 studies including 19,538 older nursing home residents with 5,223 deaths during a median of 2 years of follow-up were meta-analysed. Compared with normal weight, all-cause mortality HRs were 1.41 (95% CI = 1.26-1.58) for underweight, 0.85 (95% CI = 0.73-0.99) for overweight and 0.74 (95% CI = 0.57-0.96) for obesity. Underweight was a risk factor for higher mortality caused by infections (HR = 1.65 [95% CI = 1.13-2.40]). RR results corroborated primary HR results, with additionally lower infection-related mortality in overweight and obese than in normal-weight individuals. Like in the general population, underweight is a risk factor for mortality in old nursing home residents. However, uniquely, not only overweight but also obesity is protective, which has relevant nutritional goal implications in this population/setting.

Percutaneous endoscopic gastrostomy (PEG) tube feeding of nursing home residents is not associated with improved body composition parameters

OBJECTIVES

To study differences in nutritional status and body composition, by feeding modality, among disabled nursing home residents.

DESIGN

A retrospective chart-review study.

SETTING

A nursing wing of a public urban geriatric center.

PARTICIPANTS

Three groups of patients: non-dysphagic, orally-fed dysphagic and percutaneous endoscopic gastrostomy -fed dysphagic patients.

INTERVENTION

Standard nursing care.

MEASUREMENTS

Basal metabolic rate, total energy expenditure and nitrogen balance under oral or percutaneous endoscopic gastrostomy feeding. Dietary intake was assessed during a 3-days period by daily-food intake protocols and a 24-hours urinary creatinine excretion to detect nitrogen balance and calculate body composition parameters.

RESULTS

Data of 117 patients (55.5% females), mean age 84.6±7.5 (range 66-98 years) was analyzed. Dysphagic patients (60) differed from non-dysphagic patients (57) by lower body mass index (p=0.020), fat mass index (p=0.017), daily protein intake (p<0.0001), daily energy intake (p<0.001), protein related energy intake (p<0.001) and a negative nitrogen balance (p<0.001). In regression analyses, dysphagia was associated with increased risk of having a body mass index lower than 22.0kg/m2 (OR=2.60, 95% CI 1.135-5.943), a negative nitrogen balance (OR=2.33, 95% CI 1.063-4.669), a low fat mass index (OR=2.53, 95% CI 1.066-6.007), and low daily protein and energy intakes per body weight (OR=2.87, 95% CI 1.316-6.268 and OR=2.99, 95% CI 1.297-6.880). Compared with orally-fed dysphagic patients (21pts.), percutaneous endoscopic gastrostomy -fed patients (39pts.) received an additional mean energy intake of 30.5% kcal per day and mean protein intake of 26.0%. This additional intake was not associated with improved body composition parameters (such as fat free mass, skeletal mass or body mass index).

CONCLUSION

Dysphagic nursing home residents are characterized by worse nutritional, metabolic and body composition parameters, compared with non-dysphagic residents. Body composition parameters did not differ between orally-fed and percutaneous endoscopic gastrostomy-fed dysphagic patients, despite significantly better nutritional and metabolic parameters in PEG-fed patients. Other approaches (perhaps physical training, pharmacological etc.) should be sought to improve body composition of such patients.

Skeletal muscle mass abnormalities are associated with survival rates of institutionalized elderly nursing home residents

BACKGROUND

Knowledge about the changes in skeletal muscle mass in nursing home residents is very limited. We hypothesized that such patients have different types of skeletal muscle mass abnormalities that may affect mortality rates. Therefore, the objective of this study was to evaluate the prevalence and extent of skeletal muscle mass decline, its different clinical phenotypes (sarcopenia, wasting/atrophy and cachexia) and the mortality rates associated with these abnormalities.

METHODS

A retrospective chart-review study comprising 109 institutionalized nursing home residents. Body mass index, body fat mass, fat free mass, skeletal muscle mass and survival rates were assessed.

RESULTS

Skeletal muscle mass abnormalities were found among 73 out of 109 (67.0%) patients and were more prevalent in males compared with females (97.8% and 43.8%, respectively, p<0.001). Most of these patients had muscle wasting/atrophy (51.4%) or sarcopenia (40.3%), and 9.7% suffered from cachexia. One third of the patients with abnorrmal skeletal muscle mass showed a moderate decline of skeletal muscle mass (34.7%) while the remainder (65.3%) had very low levels of skeletal muscle mass. Each group was characterized by typical medical conditions associated with skeletal muscle mass abnormality. A Kaplan-Meier survival plot of mortality showed only lower one-year survival rates in the group with sarcopenia (60%) and muscle atrophy or cachexia (53%), compared with elderly participants with a normal skeletal muscle mass (73%), (p<0.0001). There were no significant differences in 1-year mortality rates between patients with abnormal skeletal muscle mass (whether sarcopenia, cachexia or wasting).

CONCLUSION

About two thirds of nursing home patients show skeletal muscle mass abnormalities, most within the range of very low skeletal muscle mass rather than moderately low skeletal muscle mass, that are associated with shorter survival rates, compared with normal skeletal muscle mass patients.