Hemoglobin concentration and cognitive impairment in the renal REasons for Geographic And Racial Differences in Stroke (REGARDS) Study

An Examination of the Non-linear Relationship Between Cognition and Total Hemoglobin Among the Cognitively Normal Older Adults by Gender

Objectives: This exploratory study aimed to identify the potential non-linear relationship between hemoglobin (Hgb) and cognition among cognitively normal older adults and how this relationship differs in terms of gender in generalized additive models (GAM). Methods: This is a secondary data analysis using Wave II (2010-2011) data from the National Social Life, Health, and Aging Project. A generalized additive model was used to understand the non-linear relationship between Hgb and cognition, and to identify critical Hgb point related to cognition. Results: While both genders had a non-linear association between Hgb and cognition, the degree of non-linearity was more pronounced in male older adults with EDF value close to 2. The inflection point of 15.10 g/dL for male older adults and inflection point of 11.72 g/dL for female older adults were obtained. Conclusion: Further studies are needed to validate these results and develop precision medicine approaches to integrate these results into clinical practice.

Association between hemoglobin level and cognitive profile in old adults: A cross-sectional survey

OBJECTIVE

In the present study, the association between Hemoglobin (HGB) level and cognitive profile was investigated and whether it affected the dementia risk in older adults.

METHODS

A cross-sectional population-based survey that included 3519 individuals ≥65 years of age was conducted in 2019. Basic demographic characteristics were collected. The neuropsychological assessments and blood tests were administered to evaluate cognition and HGB level. Generalized additive models were used to analyze the non-linear association between HGB levels and cognitive function. Logistics regression models were utilized to analyze the associations between HGB level and dementia risk.

RESULTS

Overall, 459 (12.7%) participants were diagnosed with dementia and there were more females (54.7%) than males (45.3%). The number of subjects with anemia (3%) or hyperhemoglobinemia (5.2%) was higher than participants with normal HGB level. A visual representation of the relationship between HGB level and Mini-Mental State Examination (MMSE) score showed an inverted U-curve, which is more evident in female. Logistics regression models showed that anemia (odds ratio, OR = 1.826, 95% confidence interval, CI: 1.166-2.860, p < 0.01), but not hyperhemoglobinemia, significantly increased the risk of dementia. These trends were not the same for males and females. An abnormal HGB level had greater effects in females, resulting in higher risk of dementia for females with anemia or hyperhemoglobinemia than subjects with normal HGB level including males.

CONCLUSION

Both low and high HGB levels can lead to cognitive decline in the incidence of dementia, indicating an inverted U-shaped curve association may exist between HGB level and global cognitive profile.

Anemia and Cognitive Performance in the ELSA-Brasil Cohort Baseline

OBJECTIVE

The association between cognitive performance and hemoglobin concentration has long been a topic of debate, but few data for middle-aged persons have been explored. The authors examined the association between anemia and cognitive performance at baseline assessment in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil), a multicenter cohort study of individuals from six Brazilian cities.

METHODS

A total of 13,624 participants (mean age=51.6 years [SD=9.0]) were included in this cross-sectional study. Cognitive performance was evaluated by using standardized scores for verbal learning, late recall, word recognition, a semantic verbal fluency test, and the Trail-Making Test, Part B (TMT-B). The association between anemia and cognitive performance was examined by using linear regression models adjusted for sociodemographic characteristics and cardiovascular risk factors.

RESULTS

Anemia was diagnosed in 713 (5.2%) participants. No association was found between anemia and worse cognitive performance for the main models. Global cognitive scores were similar between participants with and without anemia in adjusted models for the entire sample (β=-0.004; 95% CI=-0.052, 0.044) or for men (β=0.047; 95% CI=-0.053, 0.146) and women (β=-0.015; 95% CI=-0.070, 0.040) separately. In addition, hemoglobin levels (in quintile groups) were not associated with global cognitive scores. Similarly, no significant associations with anemia or hemoglobin levels were observed when each cognitive performance test was evaluated separately.

CONCLUSIONS

Anemia and hemoglobin levels were not associated with worse cognitive performance in this large cohort.

The cross-sectional association between mean corpuscular volume level and cognitive function in Chinese over 45 years old: Evidence from the China Health and Retirement Longitudinal Study

Fewer studies have focused on the independent association between mean corpuscular volume (MCV) and cognitive performance. This study was designed to characterize the cross-sectional association between MCV and cognitive performance in a large sample of Chinese residents (age≥45 years) from the China Health and Retirement Longitudinal Study (CHARLS). A total of 4023 male and 4173 female adults with MCV ≥ 80 fl were included for analysis. By multivariable linear regression analysis, for the total subjects, MCV level was significantly negatively associated with global cognitive function and episodic memory. When adjusted by sex, only in male subjects, higher MCV level was associated with reduced scores for global cognitive function, episodic memory and mental status. Via binary logistic regression analysis, the higher MCV level (MCV>100 fl) was associated with poor global cognitive function (OR = 1.601; 95% CI = 1.198–2.139; p = 0.001), episodic memory (OR = 1.679; 95% CI = 1.281–2.201; p<0.001), and mental status (OR = 1.422; 95% CI = 1.032–1.959; p = 0.031) for the whole participants. When testing this association by sex, the significant relationship between higher MCV level with worse episodic memory was observed both in male (OR = 1.690; 95% CI = 1.211–2.358; p = 0.002) and female (OR = 1.729; 95% CI = 1.079–2.770; p = 0.023) subjects; while the association between higher MCV level and poor global cognitive function (OR = 1.885; 95% CI = 1.329, 2.675; p<0.001) and mental status (OR = 1.544; 95% CI = 1.034, 2.306; p = 0.034) only existed in male subjects. Further studies are warranted to clarify the association between MCV level and cognitive performance by considering sex into consideration both cross-sectionally and longitudinally.

Hemoglobin, anemia, and poststroke cognitive impairment: A cohort study

OBJECTIVES

Several studies have demonstrated that anemia was associated with cognitive impairment. The aim of this study was to explore the relationship between hemoglobin and cognitive impairment in patient with acute ischemic stroke.

METHODS

In total, 326 patients with acute ischemic stroke were followed up for 1 month. The main outcome was the incidence and severity of poststroke cognitive impairment (PSCI) assessed by Mini-Mental State Examination (MMSE). The impact of hemoglobin levels and anemia on PSCI was assessed by multiple regression models controlling for potential confounders.

RESULTS

During the 1-month follow-up, 193 (59.2%) patients developed PSCI. Anemia was independently associated with PSCI (OR = 3.637; 95% CI, 1.216-10.881; P = .021) after adjusting for demographics, vascular risk factors, stroke severity, and functional outcome. When the hemoglobin levels stratified into tertiles, higher hemoglobin levels were associated with better cognitive function. This result was however not significant after adjusting for the same confounders above.

CONCLUSIONS

Low hemoglobin levels are associated with an increased risk of PSCI. Targeted interventions in this population may reduce the incidence of PSCI and require further evaluation.

Association between anemia and cognitive decline among Chinese middle-aged and elderly: evidence from the China health and retirement longitudinal study

Background

Our objective was to characterize the relationship of anemia and hemoglobin concentrations with cross-sectional cognitive functions and changes in cognitive functions over 2 years in a large sample of Chinese middle aged and elderly.

Methods

Ten thousand nine hundred eighteen adults aged 45 years or older participating in the China Health and Retirement Longitudinal Study (CHARLS) were used for cross-sectional analyses and 9324 were used for longitudinal analysis. Cognitive functions were assessed by memory recall (episodic memory), mental status (TICS), and global cognitive function at baseline survey (Visit 1) and first follow-up survey (Visit 2). The lower the cognitive test score, the worse the cognitive function. Anemia was defined as hemoglobin concentrations lower than 13 g/dl for men and lower than 12 g/dl for women. Adjusted multivariate regression analyses were used to explore the relationships of different cognitive domains with anemia and hemoglobin concentration.

Results

Overall, the prevalence of anemia was 12.86% and the mean hemoglobin concentration was 14.37 ± 2.20 g/dl. After adjusting for socio-demographic and health-related covariates, the cross-sectional association between anemia and global cognitive function [β (95%CI) = − 0.49(− 0.69~ − 0.29)], episodic memory [β (95%CI) = − 0.14(− 0.23~ − 0.05)], and TICS [β (95%CI) = − 0.23(− 0.38~ − 0.08)] were significant and did not differ by gender. The hemoglobin concentration was also associated with global cognitive function among the whole sample (P < 0.05 for all). The longitudinal analyses showed global cognitive function and episodic memory were associated with anemia independent of covariates (P < 0.05 for all). Sensitivity analyses further provided significant results showing the association between anemia and cognition decline (P < 0.05).

Conclusion

There was a cross-sectional and longitudinal association between anemia and accelerated decline in cognitive functions in Chinese middle-aged and elderly. This suggests that anemia and low hemoglobin concentrations are independent risk factors of cognitive decline.

Cardiovascular health and cognitive functioning among centenarians: a comparison between the Tokyo and Georgia centenarian studies

ABSTRACTObjectives:Centenarians have survived into very late life, but whether they reach very old age in good health remains unclear. The purpose of this study was to compare the cardiovascular health status and cognitive functioning of centenarians in the United States with centenarians in Japan.

DESIGN, SETTING, AND PARTICIPANTS

This cross-national design compared centenarians from the United States and Japan. The sample of U.S. centenarians was recruited from the Georgia Centenarian Study and included 287 centenarians. The sample of Japanese centenarians was recruited from the Tokyo Centenarian Study and included 304 centenarians.

MEASUREMENTS

Cognitive functioning was assessed with a mental status questionnaire, and cardiovascular disease by a health history assessment, blood pressure, and selected blood parameters.

RESULTS

The results suggest that Tokyo centenarians had lower disease experiences and BMI values, when compared to Georgia centenarians, but blood pressure was higher among Japanese centenarians. Lower levels of hemoglobin in Japanese centenarians and higher levels of C-reactive protein in Georgia were also found. The positive association of hypertension and albumin levels with cognitive functioning and the negative association of stroke occurrence with cognitive functioning were replicated in both countries. Differential effects were obtained for heart problems, BMI, and C-reactive protein (with positive effects for Tokyo centenarians, except for C-reactive protein).

CONCLUSION

For extremely old individuals, some markers of cardiovascular disease are replicable across countries, whereas differential effects for cardiovascular health also need to be considered in cardiovascular health.

Haemoglobin, magnetic resonance imaging markers and cognition: a subsample of population-based study

Background

Low haemoglobin is highly prevalent among the elderly and has been associated with dementia. However, the mechanisms underlying this association with cognitive dysfunction, either through cerebrovascular disease or neurodegeneration, remain poorly understood. We aimed to examine the association of decreased haemoglobin levels with markers of cerebral small vessel disease (CSVD), neurodegeneration and cognitive impairment in an elderly Asian population.

Methods

A total of 796 Chinese, Malay and Indian participants aged 60 years and older from the Epidemiology of Dementia in Singapore study were included in this study. After providing information on demographics, anthropometry and cardiovascular risk factors, participants underwent 3-T brain magnetic resonance imaging (MRI) to measure markers of CSVD, including cerebral microbleeds, cortical cerebral microinfarcts, lacunes, enlarged perivascular spaces and white matter hyperintensities, as well as neurodegenerative markers, including cortical thickness and subcortical structure volumes quantified using FreeSurfer. Cognition was assessed using a detailed neuropsychological assessment. Logistic and linear regression models were constructed, adjusting for age, gender, education, race, body mass index, smoking, hypertension, hyperlipidaemia, diabetes, glomerular filtration rate and other MRI markers, to test the association between haemoglobin levels and the MRI markers and cognition.

Results

Decreased haemoglobin levels were associated with cerebral microbleeds, specifically lobar microbleeds (OR, 1.21; 95% CI, 1.04–1.40; p = 0.015). Decreased haemoglobin levels were also associated with occipital cortical thinning (mean difference, − 0.011; 95% CI, − 0.019, − 0.004; p = 0.003) and smaller accumbens volume (mean difference, − 0.01; 95% CI, − 0.02, 0.00; p = 0.005). A significant association was also observed between decreased haemoglobin levels and poorer global cognitive performance (mean difference, − 0.04; 95% CI, − 0.09, 0.00; p = 0.048). In cognitive domain analysis, associations were again observed between decreased haemoglobin levels and worse performance on attention (mean difference, − 0.05; 95% CI, − 0.10, − 0.01; p = 0.028) and language (mean difference, − 0.06; 95% CI, − 0.12, 0.00; p = 0.048) domains; however, these associations did not survive multiple comparison.

Conclusions

Decreased haemoglobin levels were associated with lobar microbleeds, neurodegenerative markers and cognitive dysfunction. Future studies should ascertain whether iron, folate or vitamin B₁₂ supplementation is able to ameliorate the onset and progression of cognitive impairment and dementia associated with low haemoglobin.

Chronic kidney disease-related physical frailty and cognitive impairment: a systemic review

AIM

The objective of this review was to assess chronic kidney disease-related frailty and cognitive impairment, as well as their probable causes, mechanisms and the interventions.

METHODS

Studies from 1990 to 2015 were reviewed to evaluate the relationship between chronic kidney disease and physical frailty and cognitive impairment. Of the 1694 studies from the initial search, longitudinal studies (n = 22) with the keywords "Cognitive and CKD" and longitudinal or cross-sectional studies (n = 5) with the keywords "Frailty and CKD" were included in final analysis.

RESULTS

By pooling current research, we show clear evidence for a relationship between chronic kidney disease and frailty and cognitive impairment in major studies. Vascular disease is likely an important mediator, particularly for cognitive impairment. However, non-vascular factors also play an important role. Many of the other mechanisms that contribute to impaired cognitive function and increased frailty in CKD remain to be elucidated. In limited studies, medication therapy did not obtain the ideal effect. There are limited data on treatment strategies, but addressing the vascular disease risk factors earlier in life might decrease the subsequent burden of frailty and cognitive impairment in this population. Multidimensional interventions, which address both microvascular health and other factors, may have substantial benefits for both the cognitive impairments and physical frailty in this vulnerable population.

CONCLUSIONS

Chronic kidney disease is a potential cause of frailty and cognitive impairment. Vascular and non-vascular factors are the possible causes. The mechanism of chronic kidney disease-induced physical frailty and cognitive impairment suggests that multidimensional interventions may be effective therapeutic strategies in the early stage of chronic kidney disease. Geriatr Gerontol Int 2017; 17: 529-544.

Hemoglobin, Anemia, and Cognitive Function: The Atherosclerosis Risk in Communities Study

BACKGROUND

Our objective was to characterize the relationship of low and high hemoglobin concentrations and normocytic, microcytic, and macrocytic anemia with cross-sectional cognition and change in cognition over a median of 6 years.

METHODS

Cross-sectional and prospective analyses of 13,133 participants (mean age 57 years, 56% women, 24% black, 10% anemia) in the Atherosclerosis Risk in Communities (ARIC) study (baseline 1990-1992) were carried out. Anemia was defined as hemoglobin concentrations lower than 13g/dl for men and lower than 12g/dl for women and was subclassified as normocytic (mean corpuscular volume [MCV] 80-100 fL), microcytic (MCV < 80 fL), and macrocytic (MCV > 100 fL). Cognition was assessed by delayed word recall test (DWRT), digit symbol substitution test (DSST), word fluency test (WFT), and global Z-score at Visit 2 (1990-1992) and Visit 4 (1996-1998). Adjusted linear regression models and splines were used.

RESULTS

Cross-sectionally, anemia overall was associated with lower cognitive test scores on DSST and global Z-score among men and women (all p < .05), but not on DWRT or WFT. Anemia subtypes were associated similarly with cognition, with strongest associations for the DSST and global Z-score. Additionally, elevated hemoglobin level was associated with nonsignificantly worse cognition in cross-sectional analyses, suggesting a nonlinear association of hemoglobin with cognition. In contrast, anemia overall and anemia subtypes were not associated with cognition in prospective analyses (all p > .05).

CONCLUSIONS

There was a cross-sectional, but not prospective, nonlinear association between hemoglobin concentrations and cognitive function, although only associations of low levels of hemoglobin (anemia) were statistically significant. Subtypes of anemia had similar magnitudes of associations with cognition.

Clinical symptoms, signs and tests for identification of impending and current water-loss dehydration in older people

BACKGROUND

There is evidence that water-loss dehydration is common in older people and associated with many causes of morbidity and mortality. However, it is unclear what clinical symptoms, signs and tests may be used to identify early dehydration in older people, so that support can be mobilised to improve hydration before health and well-being are compromised.

OBJECTIVES

To determine the diagnostic accuracy of state (one time), minimally invasive clinical symptoms, signs and tests to be used as screening tests for detecting water-loss dehydration in older people by systematically reviewing studies that have measured a reference standard and at least one index test in people aged 65 years and over. Water-loss dehydration was defined primarily as including everyone with either impending or current water-loss dehydration (including all those with serum osmolality ≥ 295 mOsm/kg as being dehydrated).

SEARCH METHODS

Structured search strategies were developed for MEDLINE (OvidSP), EMBASE (OvidSP), CINAHL, LILACS, DARE and HTA databases (The Cochrane Library), and the International Clinical Trials Registry Platform (ICTRP). Reference lists of included studies and identified relevant reviews were checked. Authors of included studies were contacted for details of further studies.

SELECTION CRITERIA

Titles and abstracts were scanned and all potentially relevant studies obtained in full text. Inclusion of full text studies was assessed independently in duplicate, and disagreements resolved by a third author. We wrote to authors of all studies that appeared to have collected data on at least one reference standard and at least one index test, and in at least 10 people aged ≥ 65 years, even where no comparative analysis has been published, requesting original dataset so we could create 2 x 2 tables.

DATA COLLECTION AND ANALYSIS

Diagnostic accuracy of each test was assessed against the best available reference standard for water-loss dehydration (serum or plasma osmolality cut-off ≥ 295 mOsm/kg, serum osmolarity or weight change) within each study. For each index test study data were presented in forest plots of sensitivity and specificity. The primary target condition was water-loss dehydration (including either impending or current water-loss dehydration). Secondary target conditions were intended as current (> 300 mOsm/kg) and impending (295 to 300 mOsm/kg) water-loss dehydration, but restricted to current dehydration in the final review.We conducted bivariate random-effects meta-analyses (Stata/IC, StataCorp) for index tests where there were at least four studies and study datasets could be pooled to construct sensitivity and specificity summary estimates. We assigned the same approach for index tests with continuous outcome data for each of three pre-specified cut-off points investigated.Pre-set minimum sensitivity of a useful test was 60%, minimum specificity 75%. As pre-specifying three cut-offs for each continuous test may have led to missing a cut-off with useful sensitivity and specificity, we conducted post-hoc exploratory analyses to create receiver operating characteristic (ROC) curves where there appeared some possibility of a useful cut-off missed by the original three. These analyses enabled assessment of which tests may be worth assessing in further research. A further exploratory analysis assessed the value of combining the best two index tests where each had some individual predictive ability.

MAIN RESULTS

There were few published studies of the diagnostic accuracy of state (one time), minimally invasive clinical symptoms, signs or tests to be used as screening tests for detecting water-loss dehydration in older people. Therefore, to complete this review we sought, analysed and included raw datasets that included a reference standard and an index test in people aged ≥ 65 years.We included three studies with published diagnostic accuracy data and a further 21 studies provided datasets that we analysed. We assessed 67 tests (at three cut-offs for each continuous outcome) for diagnostic accuracy of water-loss dehydration (primary target condition) and of current dehydration (secondary target condition).Only three tests showed any ability to diagnose water-loss dehydration (including both impending and current water-loss dehydration) as stand-alone tests: expressing fatigue (sensitivity 0.71 (95% CI 0.29 to 0.96), specificity 0.75 (95% CI 0.63 to 0.85), in one study with 71 participants, but two additional studies had lower sensitivity); missing drinks between meals (sensitivity 1.00 (95% CI 0.59 to 1.00), specificity 0.77 (95% CI 0.64 to 0.86), in one study with 71 participants) and BIA resistance at 50 kHz (sensitivities 1.00 (95% CI 0.48 to 1.00) and 0.71 (95% CI 0.44 to 0.90) and specificities of 1.00 (95% CI 0.69 to 1.00) and 0.80 (95% CI 0.28 to 0.99) in 15 and 22 people respectively for two studies, but with sensitivities of 0.54 (95% CI 0.25 to 0.81) and 0.69 (95% CI 0.56 to 0.79) and specificities of 0.50 (95% CI 0.16 to 0.84) and 0.19 (95% CI 0.17 to 0.21) in 21 and 1947 people respectively in two other studies). In post-hoc ROC plots drinks intake, urine osmolality and axillial moisture also showed limited diagnostic accuracy. No test was consistently useful in more than one study.Combining two tests so that an individual both missed some drinks between meals and expressed fatigue was sensitive at 0.71 (95% CI 0.29 to 0.96) and specific at 0.92 (95% CI 0.83 to 0.97).There was sufficient evidence to suggest that several stand-alone tests often used to assess dehydration in older people (including fluid intake, urine specific gravity, urine colour, urine volume, heart rate, dry mouth, feeling thirsty and BIA assessment of intracellular water or extracellular water) are not useful, and should not be relied on individually as ways of assessing presence or absence of dehydration in older people.No tests were found consistently useful in diagnosing current water-loss dehydration.

AUTHORS' CONCLUSIONS

There is limited evidence of the diagnostic utility of any individual clinical symptom, sign or test or combination of tests to indicate water-loss dehydration in older people. Individual tests should not be used in this population to indicate dehydration; they miss a high proportion of people with dehydration, and wrongly label those who are adequately hydrated.Promising tests identified by this review need to be further assessed, as do new methods in development. Combining several tests may improve diagnostic accuracy.

Low haemoglobin levels increase unilateral spatial neglect in acute phase of stroke

Objective The objective of this study was to evaluate the relationship between unilateral spatial neglect (USN) and haemoglobin (Hb) level in acute phase of stroke. Method Cross-sectional study was performed after right hemisphere ischemic stroke. Independent variable: Hb level (mg/dL); Outcome: USN; Potential confounding factors: Age, National Institutes of Health Stroke Scale (NIHSS), and glycaemia (mg/dL); Characterization variables were obtained from electronic medical records, Hb, mean corpuscular volume (MCV) and glycaemia by laboratory exams, and USN by cancellation and bisection tasks. The relationship between Hb and USN was assessed by Spearman correlation and linear regression model. Results 40 individuals were evaluated; it was observed that the higher the Hb level, the better the USN test performance, with the two being negatively correlated. There was no significant correlation between VCM level and USN performance. Conclusion Low hemoglobin levels may indicate a worse performance in USN cancellation and bissection tests in acute phase of stroke.

Midlife iron status is inversely associated with subsequent cognitive performance, particularly in perimenopausal women

The link between iron status and cognition has been established in infants and children, yet evidence in adults is scant and heterogeneous. We examined sex- and menopause-specific cross-time associations of iron status with cognition in the French Supplémentation en Vitamines et Minéraux Antioxydants Study cohort (1539 men, 1431 pre-/perimenopausal women, 962 postmenopausal women). Serum ferritin and hemoglobin data were obtained in 1995. Cognition was assessed after a mean of 13 y through 6 validated instruments, including the RI-48 cued recall test, phonemic and semantic fluency tasks, forward and backward digit span tasks, and a trail-making test. The standardized individual test scores were summed to form a composite cognitive performance measure. Associations between ferritin and hemoglobin and subsequent cognitive performance were examined through multivariable linear regression. Among men, no significant associations were observed. In postmenopausal women, an inverse association was found between ferritin and phonemic fluency (adjusted β: -0.11; 95% CI: -0.21, -0.01). Significant inverse associations between ferritin and both the composite cognitive measure (adjusted β: -0.09; 95% CI: -0.17, -0.00) and the forward digit span scores (adjusted β: -0.13; 95% CI: -0.22, -0.03) were observed only among premenopausal women aged ≥ 46 y at baseline. No significant findings with hemoglobin emerged. This study supports an inverse association between midlife iron status and subsequent cognitive performance that is sex- and menopause-dependent. Given the urgent need for prevention research on age-related disorders, future investigations of iron status and cognition are warranted. The study is registered at www.clinicaltrials.gov as NCT00272428.

Low hemoglobin levels and recurrent falls in U.S. men and women: prospective findings from the REasons for Geographic And Racial Differences in Stroke (REGARDS) cohort

BACKGROUND

There are few data available on low hemoglobin and incident falls in the general U.S. population.

METHODS

Of 30,239 black and white U.S. adults ≥45 years in the population-based REasons for Geographic And Racial Differences in Stroke study, 16,782 had hemoglobin measured at baseline and follow-up data on falls. Hemoglobin was categorized by 1.0 g/dL increments relative to the World Health Organization anemia threshold (<13.0 g/dL for men, <12.0 g/dL for women). Recurrent falls (≥2 falls in the 6 months after baseline) were assessed during a telephone interview.

RESULTS

Recurrent falls occurred in 3.9% of men and 4.8% of women. Compared with those with a hemoglobin level 1 to 2 g/dL above the anemia cut-off, multivariable adjusted odds ratios (95% confidence intervals) for recurrent falls associated with hemoglobin levels ≥3, 2 to <3 and 0 to 1 g/dL above the cut-off point, and 0 to <1 and ≥1 g/dL below the cut-off point were 0.73 (0.45-1.19), 0.84 (0.57-1.24), 1.29 (0.88-1.90), 1.32 (0.0.80-1.2.18) and 2.12 (1.23-3.63), respectively, among men (linear trend P < 0.001), and 1.59 (1.10-2.3), 1.24 (0.95-1.62), 1.42(1.11-1.81), 1.28 (0.91-1.80) and 1.76 (1.13-2.74), respectively, among women (linear trend P = 0.45; quadratic trend P = 0.016).

CONCLUSIONS

Among men, lower hemoglobin levels were associated with an increased risk for recurrent falls. Although our findings suggest an increased risk for recurrent falls at both lower and higher hemoglobin levels among women, these findings should be confirmed in subsequent studies.

Hemoglobin decline, function, and mortality in the elderly: the cardiovascular health study

While anemia is associated with poor functional and mortality outcomes in the elderly, the impact of hemoglobin decline is less studied. We evaluated the determinants and consequences of hemoglobin decline in 3,758 non-anemic participants from the Cardiovascular Health Study, a prospective cohort of community-dwelling elderly ≥65 years old at baseline and followed for up to 16 years. Hemoglobin was measured at baseline and 3 years later and anemia defined by World Health Organization (WHO) criteria. We modeled hemoglobin decline in two ways: (1) per each 1 g/dL decrease in hemoglobin and (2) development of anemia by the WHO criteria. Among participants without baseline anemia, hemoglobin decreased by 0.4 g/dL and 9% developed anemia over 3 years. Baseline increasing age, female sex, diabetes, and kidney disease predicted hemoglobin decline over 3 years. Baseline increasing age, being African-American, and kidney disease predicted anemia development over 3 years. Hemoglobin decline was associated with subsequent worse cognitive function in men and anemia development with subsequent worse cognitive function in women. Both anemia development (HR 1.39, 95% CI 1.15, 1.69) and hemoglobin decline (HR 1.11, 95% CI 1.04, 1.18 per 1 g/dL decrease) predicted subsequent mortality in men and women. Hemoglobin decreases identified a large group of elderly individuals at risk for subsequent adverse outcomes who would not be identified using the WHO anemia criteria. These data may allow clinicians to identify at-risk elderly individuals for early intervention to improve the quality and quantity of life.