Survival-determining factors in patients with neurologic impairments who received home health care in Japan

Development and validation of a Bayesian survival model for inclusion body myositis

BACKGROUND

Associations between disease characteristics and payer-relevant outcomes can be difficult to establish for rare and progressive chronic diseases with sparse available data. We developed an exploratory bridging model to predict premature mortality from disease characteristics, and using inclusion body myositis (IBM) as a representative case study.

METHODS

Candidate variables that may be potentially associated with premature mortality were identified by disease experts and from the IBM literature. Interdependency between candidate variables in IBM patients were assessed using existing patient-level data. A Bayesian survival model for the IBM population was developed with identified variables as predictors for premature mortality in the model. For model selection and external validation, model predictions were compared to published mortality data in IBM patient cohorts. After validation, the final model was used to simulate the increased risk of premature death in IBM patients. Baseline survival was based on age- and gender-specific survival curves for the general population in Western countries as reported by the World Health Organisation.

RESULTS

Presence of dysphagia, aspiration pneumonia, falls, being wheelchair-bound and 6-min walking distance (6MWD in meters) were identified as candidate variables to be used as predictors for premature mortality based on inputs received from disease experts and literature. There was limited correlation between these functional performance measures, which were therefore treated as independent variables in the model. Based on the Bayesian survival model, among all candidate variables, presence of dysphagia and decrease in 6MWD [m] were associated with poorer survival with contributing hazard ratios (HR) 1.61 (95% credible interval [CrI]: 0.84-3.50) and 2.48 (95% CrI: 1.27-5.00) respectively. Excess mortality simulated in an IBM cohort vs. an age- and gender matched general-population cohort was 4.03 (95% prediction interval 1.37-10.61).

CONCLUSIONS

For IBM patients, results suggest an increased risk of premature death compared with the general population of the same age and gender. In the absence of hard data, bridging modelling generated survival predictions by combining relevant information. The methodological principle would be applicable to the analysis of associations between disease characteristics and payer-relevant outcomes in progressive chronic and rare diseases. Studies with lifetime follow-up would be needed to confirm the modelling results.

Tooth loss, swallowing dysfunction and mortality in Japanese older adults receiving home care services

AIM

Severe tooth loss and swallowing dysfunction occur more frequently in dependent older adult populations. Poor oral health and functional status are expected to have a negative impact on general health. We examined whether mortality is related to the number of teeth and swallowing function in dependent older Japanese individuals receiving home care services.

METHODS

Older adults aged ≥65 years who were receiving home care were included. The planned follow-up period was 3 years. Baseline data on the number of teeth, swallowing function, nutritional status, cognitive ability and activities of daily living were collected.

RESULTS

A total of 259 participants (mean age 85.0 ± 7.7 years) were enrolled. The mean length of follow up was 26.2 months. Severe tooth loss (≤9 present teeth) and swallowing dysfunction were observed in 68.0% and 32.0% of the participants, respectively. Cox's proportional hazards regression model showed that participants with both ≤9 teeth and swallowing dysfunction were at a higher risk of mortality compared with those with both ≥10 teeth and normal swallowing function (hazard ratio 2.89, 95% confidence interval 1.22-6.83). A significant interaction among severe tooth loss, swallowing dysfunction and mortality risk was observed.

CONCLUSIONS

Severe tooth loss and swallowing dysfunction were associated with increased mortality. The present study suggests that the maintenance of oral health and swallowing function has a positive effect on general health. Therefore, attention should be given to both tooth loss and swallowing function in dependent older adult populations. Geriatr Gerontol Int 2018; 18: 873-880.

Albumin, hemoglobin, body mass index, cognitive and functional performance in elderly persons living in nursing homes

The aim of this study is to produce the relation between cognitive and functional performance and some biochemical parameters in elderly population. So, we searched for the correlation between the activities of daily living (ADL), mini-mental state examination (MMSE) and body weight, age, hemoglobin, albumin, serum sodium level of 180 elderly people in five nursing homes. Face-to-face interviews and questionnaires were applied to evaluate ADL. To evaluate the cognitive function we used the MMSE. The average age of 180 people contacted was 71.5+/-5.1 (+/-S.D.), ranging 65-91 years; 112 of them were women (62.2%), 68 were men (37.8%). Of these elderly people, 25% had no medically diagnosed illnesses, whereas 17 of them (9.4%) were bedridden. There was a positive correlation between ADL and hemoglobin, albumin, body weight, cognitive function parameters and a negative one with age and serum sodium. There was a positive correlation between cognitive functions and hemoglobin, body weight, ADL and a negative one with serum sodium. Hemoglobin concentrations indicating anemia were observed in 30% of subjects, 3.9% of them had hyponatremia and 26.7% displayed a hypernatremia. There was a positive correlation between cognitive and physical function scores and hemoglobin, albumin levels in elderly patients. These results suggest that restoration of hemoglobin and albumin levels could improve cognitive and physical functional status in the elderly population.