Association between body mass index and mortality in the Korean elderly: A nationwide cohort study

The Association of Body Mass Index on Falls Risk and Mortality in Hospitalized Patients of Different Old-Age Categories Requiring Nutritional Support

Malnutrition affect clinical outcomes in hospitalized old age patients, but the data on the related outcomes on the basis of different age categories are still limited. We aimed to investigate the interplay of associations among body mass index (BMI), falls risk, and mortality rate in different older adult patient age categories. This retrospective study included hospitalized patients aged ≥ 65 years who received artificial nutrition. Demographic, biochemical, and survival data were collected. BMI was evaluated using the World Health Organization BMI cutoffs for Asians, and patients were classified into high (≥ 23.0 kg/m2), normal (18.5-22.9 kg/m2), and low (< 18.5 kg/m2) BMI groups. The Morse Fall Scale was used to assess falls risk. By age categories, all patients (n = 4,642) were divided into the 65-74 (n = 2,649) and ≥ 75 (n = 1,993) years age groups. We found that the proportion of low-BMI and high risk of falls increased with age. Further, low-BMI was associated with increased falls risk in both age groups. Overall survival rate tended to be lower in the low-BMI and ≥ 75 years group than that in other patient groups, but did not differ significantly compared with the low-BMI and 65-74 years group. Low-BMI was associated with increased falls risk and mortality; however, the association depended on specific patient age groups.

Increased Risk of Dementia Following a Diagnosis of Hearing Impairment: A South Korean Nationwide Cohort Study

BACKGROUND

Among the older adults, hearing impairment is a common problem and may contribute to dementia.

OBJECTIVE

Therefore, we aimed to examine the association between hearing impairment and the risk of dementia among older adults in South Korea.

METHODS

Using the Korean National Health Insurance Service-Senior Cohort from 2005 to 2019, we collected data of 44,728 patients. Hearing impairment was determined using the national disability registry. Propensity score matching (1:1) was performed to match patients with and without hearing impairment (case: 22,364, control: 22,364). A Cox proportional hazards regression model was built to analyze the association between hearing impairment and dementia.

RESULTS

Patients with hearing impairment had a higher risk of dementia than those without hearing impairment (hazard ratio [HR] = 1.28, 95% confidence interval [CI] = 1.23-1.34). Assessing the degree of disability, both severe (HR = 1.25, 95% CI = 1.16-1.35) and mild conditions (HR = 1.29, 95% CI = 1.23-1.35) had an increased risk of dementia, respectively.

CONCLUSIONS

Older patients with hearing impairment exhibit an increased risk of dementia, thereby warranting a new approach to dementia care among these patients regardless of the degree of hearing impairment.

Malnutrition significantly affected centenarian prognoses: A prospective study with 5-year follow-up

BACKGROUND

The world is currently facing a much-needed conundrum, and population aging has become an important worldwide problem. Appropriate nutritional intervention could prolong survival time and reduce mortality rate. However, scarce study has involved the effects of nutrition on survival time in centenarians and evaluated the malnutrition with prognostic nutritional index (PNI) in relation to healthy aging. This prospective study was designed to investigate the effects of malnutrition through PNI assessment on mortality rate and survival time with 5-year follow-up in Chinese centenarians.

METHODS

A household survey was conducted on the centenarians in 18 cities and counties of Hainan province, and malnutrition was evaluated by PNI as an effective tool in 423 centenarians followed up for 5-year.

RESULTS

Prevalence of malnutrition was 19.4%. Body mass index (BMI) was significantly lower and malnutrition was significantly more in the dead group than those in the survival group (all P < 0.05). Multivariate Cox regression analysis indicated that BMI [Hazard ratio (HR): 0.913; 95%CI: 0.854-0.977] negatively affected mortality rate, whereas malnutrition (HR: 2.630; 95%CI:1.474-4.695) positively affected mortality rate in centenarians (all P < 0.05). When BMI was <18.5 kg/m2, malnutrition (HR: 4.401; 95%CI: 1.948-9.943) also positively affected mortality rate (P < 0.05).

CONCLUSIONS

This prospective study with 5-year follow-up demonstrated that malnutrition had positive effect on mortality rate, especially when BMI was lower than 18.5 kg/m2, in Chinese centenarians. In order to reduce mortality rate and prolong survival time, it is essential to pay attention to malnutrition in elderly population.

The Obesity Paradox and Mortality in Older Adults: A Systematic Review

“Obesity paradox” describes the counterintuitive finding that aged overweight and obese people with a particular disease may have better outcomes than their normal weight or underweight counterparts. This systematic review was performed to summarize the publications related to the obesity paradox in older adults, to gain an in-depth understanding of this phenomenon. PubMed©, Embase©, and Scopus© were used to perform literature search for all publications up to 20 March 2022. Studies were included if they reported data from older adults on the relation between BMI and mortality. The following article types were excluded from the study: reviews, editorials, correspondence, and case reports and case series. Publication year, study setting, medical condition, study design, sample size, age, and outcome(s) were extracted. This review has been registered with PROSPERO (no. CRD42021289015). Overall, 2226 studies were identified, of which 58 were included in this systematic review. In all, 20 of the 58 studies included in this review did not find any evidence of an obesity paradox. Of these 20 studies, 16 involved patients with no specific medical condition, 1 involved patients with chronic diseases, and 2 involved patients with type 2 diabetes mellitus. Seven out of the nine studies that looked at short-term mortality found evidence of the obesity paradox. Of the 28 studies that examined longer-term mortality, 15 found evidence of the obesity paradox. In the studies that were conducted in people with a particular medical condition (n = 24), the obesity paradox appeared in 18 cases. Our work supports the existence of an obesity paradox, especially when comorbidities or acute medical problems are present. These findings should help guide strategies for nutritional counselling in older populations.

Associations between obesity, self-reported weakness and their combinations with mortality in nursing home residents

OBJECTIVES

There are studies on associations between obesity and mortality in nursing home (NH) residents, but the presence of concomitant muscle weakness has not been examined. We considered that self-reported weakness might be a low muscle strength proxy marker. We aimed to examine associations of obesity alone, self-reported muscle weakness alone, and their combination with mortality in NH residents.

METHODS

This is a retrospective longitudinal follow-up study. We noted age, sex, nutritional status, functionality, number of chronic diseases, and regular medication. Obesity was assessed by the body fat-percentage method estimated by bioimpedance analysis. Weakness was identified by self-reported muscle weakness. Survival was evaluated with a univariate log-rank test and multivariate Cox regression analyses.

RESULTS

We included 214 participants. In a median follow-up time of 46 months, mortality occurred in 37.4%. In multivariate analysis adjusted by age, sex, undernutrition, number of chronic diseases, and regular medication, functional scores; 'non-weak non-obese' participants or 'weak alone' participants or 'weak+obese' participants had higher mortality risk when compared with the 'obesity alone' participants [hazard ratio (HR) = 2.6, 95% confidence interval (CI) = 1.2-5.5, p = 0.01; HR = 2.6, 95% CI = 1.2-5.9, p = 0.02; HR = 3.0, 95% CI = 1.2-7.7, p = 0.02].

CONCLUSION

This is the first report showing that obesity was associated with lower mortality risk if the weakness was not present in NH residents. However, obesity with concomitant weakness was associated with mortality risk similar to non-weak non-obese or weak alone participants. Our study suggests a simple consideration of weakness that can easily be integrated into everyday practice.

Association Between Body Mass Index and All-Cause Mortality in a Prospective Cohort of Southern Chinese Adults Without Morbid Obesity

Objective: This prospective study examined the relationship between body mass index (BMI) and all-cause mortality in Chinese adults without morbid obesity.

Methods: We prospectively examined the relationship between BMI and all-cause mortality in 12,608 Southern Chinese adults with age ≥35 years who participated in the National Key R&D Program from 2013–2014 to 2019–2020. Cox proportional hazards models were used to examine the association between BMI and all-cause mortality.

Results: The prevalence of being underweight, normal weight, overweight and having moderate obesity was 7.36%, 55.83%, 28.51% and 8.31%, respectively. A total of 683 (5.65%) deaths occurred during a median follow-up period of 5.61 years. The Cox proportional hazards models indicated that a continuous BMI level was negatively associated with all-cause mortality [adjusted-hazard ratio (HR) per 1 kg/m² increase: 0.96, 95% CI 0.93 to 0.98, p < 0.001]. Furthermore, the HRs of all-cause mortality in the underweight, overweight and moderate obesity groups were 1.31 (1.05, 1.64), 0.89 (0.73, 1.08) and 0.64 (0.44, 0.92), respectively in the confounder model relative to the normal weight group. Survival analysis further confirmed this inverse association of the four BMI categories with mortality.

Conclusion: BMI was negatively associated with all-cause mortality in southern Chinese adults without morbid obesity. Compared to the normal weight category, adults in the moderate obesity category had lower all-cause mortality, whereas being underweight was associated with increased all-cause mortality.

Impact of underweight on 3-year all-cause mortality in patients with acute severe hypertension: a retrospective cohort study

Body mass index (BMI) is used to measure body fat. We investigated the association between BMI and long-term clinical outcomes in patients with acute severe hypertension who visited the emergency department (ED). Cross-sectional study data were obtained from a single regional emergency medical center, including patients with elevated initial systolic blood pressure ≥ 180 mmHg or diastolic blood pressure ≥ 100 mmHg. The patients were classified into five groups according to BMI level (underweight, normal, overweight, obese class I, II and III). Among 4867 patients who presented with acute severe hypertension at the ED, 935 (19.21%) died within 3-years. In particular, 140 (44.59%) patients in the underweight group died from any cause, which was the highest among the five groups, and there was a reverse J-shaped association between BMI and 3-year all-cause mortality. Underweight patients had a significantly increased risk of all-cause mortality by 1.55-fold during the 3-year follow-up. Rather, obesity was associated with a reduction in the 3-year all-cause mortality. Comorbidities, including chronic kidney disease and acute hypertension-mediated organ damage, were independent predictors of all-cause mortality in patients who were not underweight. Underweight contributes to worsening long-term clinical outcomes in patients with acute severe hypertension. Clinicians should consider BMI as one of the physical examination parameters in patients with acute severe hypertension, and management including lifestyle modifications such as diet control and exercise should be undertaken considering BMI and comorbidities.

Long-Term Mortality in Critically Ill Tracheostomized Patients Based on Home Mechanical Ventilation at Discharge

Data regarding the long-term outcomes for tracheostomized patients receiving home mechanical ventilation (HMV) are limited. We aimed to determine the 1-year mortality rate for critically ill tracheostomized patients with and without HMV. Data of tracheostomized patients between 1 January 2015 and 31 December 2019 were analyzed. A Kaplan-Meier analysis was performed to assess the survival curve of the patients. Among the 124 tracheostomized patients, 102 (82.3%) were weaned from mechanical ventilation (MV), and 22 (17.7%) required HMV at discharge. The overall 1-year mortality rate was 47.6%, and HMV group had a significantly higher 1-year mortality rate than those weaned from MV (41.2% vs. 77.3%, p = 0.002). In the Cox proportional hazards regression, BMI (HR 0.913 [95% CI 0.850-0.980], p = 0.012), Sequential Organ Failure Assessment (SOFA) score (HR 1.114 [95% CI 1.040-1.193], p = 0.002), transfer to a nursing facility (HR 5.055 [95% CI 1.558-16.400], p = 0.007), and HMV at discharge (HR 1.930 [95% CI 1.082-3.444], p = 0.026) were significantly associated with 1-year mortality. Critically ill tracheostomized patients with HMV at discharge had a significantly higher 1-year mortality rate than those weaned from MV. Low BMI, high SOFA score, transfer to a nursing facility, and HMV at discharge were significantly associated with 1-year mortality.

A Simple Model for Predicting 10-Year Cardiovascular Risk in Middle-Aged to Older Chinese: Guangzhou Biobank Cohort Study

The aim of this paper is to develop 10-year cardiovascular disease (CVD) risk prediction models for the contemporary Chinese populations based on the Guangzhou Biobank Cohort Study (GBCS) and to compare its performance with models based on Framingham's general cardiovascular risk profile and the Prediction for Atherosclerotic CVD Risk in China (China-PAR) project. Subjects were randomly classified into the training (n = 15,000) and validation (n = 12,721) sets. During an average of 12.0 years' follow-up, 3,732 CVD events occurred. A 10-year sex-specific CVD risk prediction model including age, systolic blood pressure, use of antihypertensive medication, smoking, and diabetes was developed. Compared with the Framingham and China-PAR models, the GBCS model had a better discrimination in both women (c-statistic 0.72, 95% CI 0.71-0.73) and men (c-statistic 0.68, 95% CI 0.67-0.70), and the risk predicted was closer to the actual risk. This prediction model would be useful for identifying individuals at higher risks of CVD in contemporary Chinese populations.

Effectiveness of home visiting on patients with hypertension: A systematic review and meta-analysis

BACKGROUND

Blood pressure lowering treatments can help prevent cardiovascular disease. However, little is known about the possibility of home visiting programs for hypertension. This study aims to evaluate the effectiveness of home visiting programs on hypertensive patients.

METHODS

We systematically reviewed the medical literature and performed a meta-analysis. Five electronic databases were systematically searched from their inception to September 2019. Two reviewers independently assessed the risk of bias of the studies included in the review using tools developed by the Cochrane Collaboration. The meta-analysis was performed using Review Manager software (version 5.3).

RESULTS

Thirteen RCTs with 2674 participants were identified. The home visiting program demonstrated a greater reduction in systolic blood pressure (MD = -5.63, 95% confidence interval (CI): -8.32 to -2.94), diastolic blood pressure (MD = -4.14, 95% CI: -6.72 to -1.56) and waist circumference (MD = -2.61, 95% CI: -3.5, -1.72) during a 6 month intervention. However, there were no significant differences between the groups in terms of body mass index, weight, or blood lipids.

CONCLUSION

Home visiting programs were associated with improved BP control and reduced blood pressure, which indicate that it might be an effective method for management of hypertension.

Hypertriglyceridemia Is an Independent Risk Factor for Cardiovascular Diseases in Korean Adults Aged 30-49 Years: a Nationwide Population-Based Study

Objective

This study was conducted to estimate the incidence of cardiovascular disease (CVD) independently from low-density lipoprotein (LDL) cholesterol according to triglyceride (TG) levels in young adults.

Methods

Subjects aged 30–49 years with data from routine health check-ups provided by the National Health Insurance Service during 2009 were selected. The primary outcome was incident CVD, defined as a composite of ischemic heart disease and ischemic stroke during the follow-up period from 2009 to 2018.

Results

The mean age of study subjects (n=1,823,537) was 40.1±5.7 years, and the median follow-up period was 8.3 years. The quartiles of serum TG levels at the baseline were calculated: Q1, <74 mg/dL; Q2, 74–108 mg/dL; Q3, 109–166 mg/dL; and Q4: >166 mg/dL. The highest quartile of TG levels (Q4) had a significantly higher risk of the primary outcome than Q1 (hazard ratio [HR], 2.40 [95% confidence interval; CI, 2.33–2.47]). Q2 and Q3 also experienced the primary outcome more frequently than Q1 (HR, 1.37 [95% CI, 1.33–1.42] and HR, 1.80 [95% CI, 1.75–1.86], respectively). Even after adjustment for age, sex, obesity, alcohol drinking amount, smoking, LDL cholesterol, diabetes mellitus, hypertension, lipid-lowering medication use, and family history of CVD, there was a significant dose-response relationship between TG quartiles and the risk of the primary outcome (HR per quartile, 1.13 [95% CI, 1.12–1.14]).

Conclusion

In conclusion, in the Korean population aged 30–49 years, high TG levels independently increased future CVD risk in both men and women.

Association between intensive glycemic control and mortality in elderly diabetic patients in the primary care: A retrospective cohort study

OBJECTIVE

To examine the association between the most recent HbA1c values and the mortality of elderly Type 2 Diabetic (T2DM) patients managed in the public primary care setting and to explore the associating risk factors.

DESIGN

Retrospective cohort study.

SUBJECTS

All T2DM patients aged 65 or above, who attended a public primary care clinic for regular follow up from 01/01/2012 to 31/12/2012 were included. Their follow up status till 31/12/2017 was reviewed. Those who were deceased on or before 31/12/2017 were matched randomly with controls that were alive in the same cohort for comparison.

MAIN OUTCOME MEASURES

Patients' demographics, smoking status, duration of T2DM, biochemical parameters including the most recent HbA1c, lipid profile, renal function test, drug profile, co-morbidities and all-cause mortality were retrieved from Hospital Authority's CDARS and CMS systems.

RESULTS

Both high (>8.0%) and low (<6.5%) HbA1c values were associated with increased odd ratio of all-cause mortality among T2DM elderly patients treated in the primary care. There was a 3-fold increase in odd ratio when the HbA1c reading was very low (<6.0%). Associated risk factors for all-cause mortality in elderly T2DM patients included smoker status, lower BMIs, and higher LDL levels and use of sulphonylureas.

CONCLUSIONS

Glycemic target for elderly T2DM patients should be approached cautiously. Over-aggressive treatment may lead to increased mortality among elderly T2DM patients.

Trajectories of Body Mass Index and Their Associations with Mortality among Older Adults in Korea: Analysis of the Korean Longitudinal Study of Aging

Background

Weight change is a known risk factor for mortality. Previous Korean studies only considered mortality consequences of weight change between two time points over relatively short periods. This study investigated whether body mass index (BMI) trajectory patterns were associated with all cause-mortality based on continuous BMI observations during a 10-year follow-up period among Korean older adults.

Method

This study analyzed data from the 2006–2016 Korean Longitudinal Study of Aging database. The participants included in this study were 3,478 people aged 65 years or older who had no previous cancer history. A trajectory model was developed to classify different homogeneous trajectory subgroups according to BMI, and Cox proportional hazards models were used to investigate the association of BMI trajectory with all-cause mortality.

Result

We identified four trajectory groups: obese (OG); overweight (OWG); high normal weight (HNWG); and low normal weight (LNWG). The LNWG and HNWG experienced continuous weight loss during the study period. Trajectories with higher BMI were associated with lower mortality. The adjusted hazard ratios (95% confidence intervals) for all-cause mortality in the LNWG, HNWG, and OWG were 2.40 (1.69–3.40), 1.75 (1.26–2.45), and 1.38 (0.99–1.96), respectively, compared with those in the OG.

Conclusion

We found that the lower the BMI of the weight trajectory group, the higher the mortality over 10 years in Korean older adults. This result suggested that baseline obesity status and degree of weight loss during follow-up contributed to mortality in later life.

Dietary recommendations for patients with dementia

With the emergence of support for diet in the maintenance of cognition, clinicians have been justifiably eager to promote diet recommendations for their older patients. But popular diets, such as the Mediterranean diet, Dietary Approaches to Stop Hypertension (DASH), and the Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND), have not been shown to benefit cognition among patients who already have dementia or cognitive decline. In our experience, promoting these restrictive diets can be detrimental to patients with dementia who are already prone to eating disturbance; vulnerable to malnutrition; and, if underweight, demonstrate increased mortality. Moreover, we have seen both patient and caregiver satisfaction negatively affected by dietary modification. Clinicians need to be aware that any dietary recommendations for patients with dementia should be mitigated by the lack of evidence for improvement in cognition, the risks for exacerbating poor nutrition, and the potential for further limiting their quality of life.