Comparison of the Physical Function Trajectories in Three Birth Cohorts of Chinese Older Adults: A 14-Year Longitudinal Study

OBJECTIVES

It remains uncertain whether the favorable trend of reduction in physical disabilities has become reversed in the recent-born cohorts of older adults. This study aimed to compare the rate of decline with time in self-reported Instrumental Activity of Daily Living (IADL) difficulties, objective measurement of gait speed and grip strength, in three birth cohorts of Chinese older adults.

DESIGN

A prospective cohort study.

SETTING AND PARTICIPANTS

Four thousand Chinese older adults aged 65 years or above in three birth cohorts (1934-1938, 1929-1933, 1905-1928) were recruited from the community in Hong Kong.

MEASUREMENTS

Grip strength, gait speed and IADL difficulties were measured between 2001 to 2017. Joint models were used to examine the trajectories of grip strength, gait speed and IADL difficulties over time, and the interaction effect of age-by-cohort (or also age2-by-cohort) was also examined.

RESULTS

The recently born cohort (1934 - 1938) had worse grip strength and more IADL difficulties at the same age than the earlier two cohorts (1929 - 1933; 1905 - 1928). Furthermore, the most recently born cohort also followed a more rapid decline longitudinally with a greater decline observed in gait speed, grip strength and IADL difficulties for women whereas a greater decline in grip strength and IADL difficulties for men.

CONCLUSIONS

The continuous improvement of physical limitations in old age may have halted and there appears to be a reversal of this favourable trend in the recent born cohort of older adults living in Hong Kong.

Cardiac Manifestations of Sarcopenia

OBJECTIVES

Screening questions for sarcopenia used in the community (SARC-F) may be regarded as indicators of exercise tolerance.

DESIGN

Observational study.

SETTING

We tested the hypothesis that community-living older people who are screened positive for sarcopenia using the SARC-F tool but without a history of heart failure (HF) have a higher prevalence of cardiac abnormalities compared with those who are SARC-F negative.

PARTICIPANTS

Participants were recruited from a territory-wide primary care needs assessment for older people based in community centres, and from non-acute hospitals in the same region as the study centre.

MEASUREMENTS

Participants with a total score of >=4 and who did not have any history of HF were invited to attend for further cardiac assessment. Grip strength, walking speed, and the 6-minute walk test and echocardiography were carried out. Patients with frailty and at least Grade II diastolic dysfunction were considered to have heart failure with preserved ejection fraction (HFpEF) if they also had concomitant elevated N-terminal prohormone of B-type natriuretic peptide (NT-proBNP) of at least 300 pg/ml.

RESULTS

Diastolic dysfunction (DD) was significantly associated with SARC-F score >=4 and higher circulating NT-proBNP levels. ROC curves evaluating the predictive values of SARC-F, HGS and gait speed for DD showed that a combination of SARC-F and HGS or gait speed provided significant incremental value in predicting DD.

CONCLUSIONS

Community living older people with sarcopenia detected using a simple questionnaire have a higher prevalence of DD accompanied by elevated NT proBNP. Addition of hand grip strength or walking speed improve the magnitude of the association. SARC-F may be used as a tool to detect early cardiac dysfunction in the community.

P1925Machine learning versus classic electrocardiographic criteria for left ventricular hypertrophy in a young pre-participation cohort: results from the SAFE protocol study

Background/Introduction

Classic electrocardiographic (ECG) criteria for left ventricular hypertrophy (LVH) have been well studied in Western populations, particularly in hypertensive patients. However, their utility in Asian populations is not well studied, and their applicability to young pre-participation cohorts is unclear. We sought to evaluate the performance of classical criteria against that of machine learning models.

Aims

We sought to evaluate the performance of classical criteria against the performance of novel machine learning models in the identification of LVH.

Methodology

Between November 2009 and December 2014, pre-participation screening ECG and subsequent echocardiographic data was collected from 13,954 males aged 16 to 22, who reported for medical screening prior to military conscription.

Final diagnosis of LVH was made on echocardiography, with LVH defined as a left ventricular mass index >115g/m2. The continuous and binary forms of classical criteria were compared against machine learning models using receiver-operating characteristics (ROC) curve analysis. An 80:20 split was used to divide the data into training and test sets for the machine learning models, and three fold cross validation was used in training the models. We also compared the important variables identified by machine learning models with the input variables of classical criteria.

Results

Prevalence of echocardiographic LVH in this population was 0.91% (127 cases). Classical ECG criteria had poor performance in predicting LVH, with the best predictions achieved by the continuous Sokolow-Lyon (AUC = 0.63, 95% CI = 0.58–0.68) and the continuous Modified Cornell (AUC = 0.63, 95% CI = 0.58–0.68). Machine learning methods achieved superior performance – Random Forest (AUC = 0.74, 95% CI = 0.66–0.82), Gradient Boosting Machines (AUC = 0.70, 95% CI = 0.61–0.79), GLMNet (AUC = 0.78, 95% CI = 0.70–0.86). Novel and less recognized ECG parameters identified by the machine learning models as being predictive of LVH included mean QT interval, mean QRS interval, R in V4, and R in I.

ROC curves of models studies

Conclusion

The prevalence of LVH in our population is lower than that previously reported in other similar populations. Classical ECG criteria perform poorly in this context. Machine learning methods show superior predictive performance and demonstrate non-traditional predictors of LVH from ECG data. Further research is required to improve the predictive ability of machine learning models, and to understand the underlying pathology of the novel ECG predictors identified.

P308Utility of a prominent R wave in lead V1 of a resting electrocardiogram for detecting significant cardiac pathology in an unselected population of young males

Background

Pre-participation electrocardiogram (ECG) screening is proposed as a means to detect cardiac pathology in asymptomatic individuals, and to select individuals for further cardiac investigation. Isolated ECG finding of Right Ventricular Hypertrophy (RVH) does not require further investigation based on the recent 2017 International Criteria. However, a prominent R wave in V1 has been described in cardiac abnormalities such as Wolff-Parkinson-White syndrome, hypertrophic cardiomyopathy, cardiomyopathy in Duchenne muscular dystrophy, arrhythmogenic right ventricular cardiomyopathy (ARVC), atrial septal defect and pulmonary hypertension.

Purpose

We sought to examine the utility of a prominent R wave in V1 as a screening criterion in an asymptomatic young male population of predominantly non-athletes, to detect significant structural cardiac pathology.

Methods

As part of the Singapore Armed Forces Electrocardiographic and Echocardiographic (SAFE) Protocol Study, pre-military enlistment screening ECG data was collected from 144,346 males between the ages of 16 to 22 from November 2009 to December 2014. Patients with ECGs with a prominent R wave, defined as an R wave ≥0.5mV in lead V1 with an R/S ratio of ≥1, were sent to a tertiary medical facility for a detailed transthoracic echocardiogram and subsequent cardiologist review. Any cardiac pathology identified was deemed significant if it led to the patient being excluded from participation in vigorous physical activity.

Results

1,144 patients with an isolated prominent R wave in V1 were studied. The mean age was 18.2±1.09 years and 81% were of Chinese ethnicity. None of the patients had echocardiographic evidence of RVH, 5 patients had a dilated right ventricle and 3 individuals had an elevated pulmonary artery systolic pressure. 11 patients (0.96%) had significant structural heart disease known to be associated with a prominent R wave in V1 that excluded them from participation in physical activity. These included large atrial septal defects (n=8), pulmonary stenosis (n=1), total anomalous pulmonary venous return (n=1) and hypertrophic cardiomyopathy (n=1). The test has a sensitivity of 21.6%, specificity of 93.4%, positive predictive value of 0.96% and negative predictive value of 99.8%,

Performance As Screening Criteria Number of Patients With Cardiac Pathology In Those Tested Positive Number of Patients With Cardiac Pathology In Those Tested Negative Positive Predictive Value (%) Negative Predictive Value (%) Sensitivity (%) Specificity (%) 11 40 0.96 99.8 21.6 93.4

Significant Cardiac Pathology Identified

Conclusion

A prominent R in V1 is not associated with echocardiographic RVH, or ARVC even in a large predominantly non-athletic male population. However, 0.96% of such patients would have other significant cardiac pathologies such as a large atrial septal defect.

Utility of the FRAIL Questionnaire in Detecting Heart Failure with Preserved Ejection Fraction

OBJECTIVE

To test the utility of the FRAIL questionnaire as a screening tool for heart failure.

DESIGN

Cross sectional study.

SETTING

Chinese older people in Hong Kong.

PARTICIPANTS

Participants aged 60 years and over were recruited from a territory-wide primary care needs assessment for older people based in community centers as well as two nonacute hospitals.

MEASUREMENTS

Questionnaire administered included the five-item FRAIL scale, and information regarding sociodemographic data, smoking and alcohol use, history of cardiovascular disease and diabetes, and heart failure symptoms. Handgrip strength, walking speed and 6 minute walk distance were recorded. Cardiac assessment included electrocardiogram, echocardiography, and blood assay for N-terminal prohormone of B-type natriuretic peptide (NT-proBNP).

RESULTS

The prevalence of diastolic dysfunction was high, being 52% in the robust group, increasing to 65% in the pre-frail and 85% in the frail group. This finding is accompanied by a corresponding increase in NT-proBNP from 64.18 pg/ml in the robust group, to 118.57 pg/ml in the pre-frail and 167.98 pg/ml in the frail group. Three of the five components of the FRAIL scale, fatigue, resistance and ambulation, were associated with increased odds ratios of diastolic dysfunction among those aged 75 years and older, while resistance alone was associated with increased odds ratio among those less than 75 years old.

CONCLUSION

Frailty is associated with heart failure with preserved ejection fraction (HFpEF), and frailty screening may be used to detect undiagnosed HFpEF. The findings support the proposal that HFpEF be considered a geriatric syndrome.

How Dietary Patterns are Related to Inflammaging and Mortality in Community-Dwelling Older Chinese Adults in Hong Kong - A Prospective Analysis

INTRODUCTION

Studies examining dietary patterns and inflammageing in relation to mortality are limited.

OBJECTIVE

We examined the influence of various dietary patterns on all-cause and cardiovascular disease (CVD) mortality, taking into account demographics, lifestyle factors, and serum inflammatory markers.

METHODS

We conducted multivariate Cox regression analyses using data from a cohort of community-dwelling older Chinese adults (1,406 men, 1,396 women) in Hong Kong. Baseline interviewer administered questionnaires covered dietary intake estimation and dietary pattern generation from the food frequency questionnaire, demographic and lifestyle factors, cognitive function and depressive symptoms. Serum high-sensitivity C-reactive protein (hsCRP) and 25-hydroxyvitamin D (25OHD) were measured. All-cause and CVD mortality data at 14-year follow up were retrieved from an official database.

RESULTS

In men, higher hsCRP level was associated with lower Diet Quality Index-International (DQI-I) score, Mediterranean-DASH Intervention for Neurodegenerative Delay Diet (MIND) score, Okinawan diet score, "vegetables-fruits" pattern score and "snacks-drinks-milk" pattern score. Higher serum 25OHD level was associated with higher Mediterranean Diet Score (MDS) but lower "snacks-drinks-milk" pattern score. None of the dietary pattern scores was associated with all-cause or CVD mortality after adjusting for all covariates. In women, hsCRP level and serum 25OHD level were not associated with any dietary patterns. Higher DQI-I score (HR=0.77 (95% CIs: 0.59, 0.99) highest vs. lowest tertile, p-trend=0.038) and Okinawan diet score (HR=0.78 (95% CIs: 0.61, 1.00) highest vs lowest tertile, p-trend=0.046) was associated with a lower risk of all-cause mortality, whereas higher MIND score (HR=0.63 (95% CI: 0.36, 1.09) highest vs. lowest tertile, p-trend=0.045) was associated with a reduced risk of CVD morality in the multivariate adjusted model.

CONCLUSION

Higher DQI-I score and Okinawan diet score were associated with a lower risk of all-cause mortality, and higher adherence to the MIND diet was related to a reduced risk of CVD mortality in community-dwelling Chinese older women.

Decline and Peripheral Redistribution of Fat Mass in Old Age - A Four-Year Prospective Study in 3018 Older Community-Living Adults

BACKGROUND

It is widely recognized that fat will accumulate with ageing and is more prominent centrally. However, there were studies reported that fat might not gain either centrally or generally with ageing.

METHODS

The baseline, 2-year and 4-year total body fat mas, trunk fat mass and percentage fat mass, were measured by DXA in 3018 community-living Chinese older than 65 years. The respective 4-year trajectories of adiposity were analyzed by repeated measure ANOVA p-for-trend test.

RESULTS

There was a trend of increase in total body fat mass in men and a decreasing trend in women but neither reached statistical significance. However, there was a significant increase in percent fat mass in both genders. Fat mass was relatively stable in the 2 young-old groups but it declined in the oldest group, aged 75 years or above. (men, p=0.017; women, p<0.001). On the contrary, a corresponding rise of percent fat mass was observed, which was steeper in the 2 younger age groups but did not change in the oldest group. For trunk fat mass, there was a statistically significant decreasing trend in women (p < 0.001) but it remained static in men (p = 0.092). The fat mass in upper limbs of both genders did not change but for the lower limbs, there was a statistically significant increase in both men (p < 0.001) and women (p < 0.02).

CONCLUSION

Absolute total body fat mass does not accumulate in old age and in the contrary, in the oldest old group (75 years or above), it declined instead. With ageing, fat will redistribute from the central region to the lower limbs.

The selection of a screening test for frailty identification in community-dwelling older adults

BACKGROUND

Frailty in older Chinese has been less often studied and the selection of one screening test feasible in primary care and population survey is needed. We attempted to examine the sensitivity and specificity of each of the five Fried's criteria as a single screening test in the identification of frailty.

METHODS

We recruited 4000 community-dwelling Chinese adults 65 years or older stratified by 3 age-stratum and identified frailty as having 3 or more of Fried's criteria: underweight(BMI<18.5), handgrip strength(

RESULTS

The proportion of frailty in the 3 age groups (65-69 years, 70-74 years, 75 years and above) were 2.3%, 3.4% and 11.9% respectively in men and 1.4%, 2.6% and 11.6% in women. Among the 5 criteria, walking speed, grip strength and physical activity (PASE score) divided at their respective lowest quintile values, achieved similar Area Under Curve in the Receiver Operating Characteristics analysis. For walking speed, the sensitivity and specificity were 82.7% and 83.1% in men and 91.9% and 84.5% in women respectively. For grip strength, the corresponding values were 89.5% and 80.6% in men; and 84.5% and 81.9% in women. For physical activity, they were 83.7% and 83.5% in men; and 82.8% and 84.7% in women.

CONCLUSION

Either walking speed or grip strength measurement may be suitable for frailty screening in primary care or population health survey. A cut-off value of 0.9 m/s in walking speed and 28 kg in grip strength for older men; and a corresponding value of 0.8 m/s and 18 kg for older women is recommended for the screening of frailty in community-dwelling older Chinese adults.

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Key Words Collapse

MESH Headings

• Aged
• Asian People
• Body Mass Index
• Fatigue
• Female
• Frail Elderly
• Geriatric Assessment/methods
• Hand Strength
• Humans
• Male
• Prospective Studies
• ROC Curve
• Socioeconomic Factors
• Thinness
• Walking

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Grants Collapse

Affiliation(s)

T W Auyeung Tung Wai Auyeung, The S. H. Ho Centre for Gerontology and Geriatrics, The Chinese University of Hong Kong, Department of Medicine and Geriatrics, Pok Oi Hospital, Au Tau, NT, Hong Kong, Email : , Telephone: 852 24868985, Fax: 852 24868976
J S W Lee
J Leung
T Kwok
J Woo

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Physical frailty in older adults is associated with metabolic and atherosclerotic risk factors and cognitive impairment independent of muscle mass

OBJECTIVE

Metabolic and atherosclerotic diseases are known risk factors for disability in old age, and can result in sarcopenia as well as cognitive impairment, which are both components of frailty syndrome. As muscle loss increases with ageing, it is unclear whether muscle loss per se, or the diseases themselves, are the underlying cause of physical frailty in those suffering from these diseases. We tested the hypothesis that metabolic and atherosclerotic diseases and cognitive impairment are associated with physical frailty independent of muscle loss in old age, and further examined their impact on the relationship between physical frailty and mortality.

DESIGN

Prospective.

SETTING

Community.

PARTICIPANTS

4000 community dwelling Chinese elderly ≥65 years.

MEASUREMENTS

Diabetes, hypertension, stroke, heart disease, cognitive impairment, smoking, physical activity, waist hip ratio (WHR) and ankle-brachial index (ABI)) were recorded. Physical frailty measurements (grip-strength, chair-stands, stride length and 6-metre walks) were summarized into a composite frailty score (0-20), 0 being the most frail) according to quartiles of performance. Appendicular muscle mass (ASM) was measured using dual X-ray absorptiometry. Relationships between the score and covariates were analyzed. Cox regression was used to study the impact of metabolic and atnerosclerotic risk factors on the relationship between physical frailty and 6-year mortality.

RESULTS

After adjustment for ASM, all metabolic diseases and indexes, and cognitive impairment were significantly associated with the composite physical frailty score in univariate analysis. In multivariate analysis, cognitive impairment, high WHR, diabetes, stroke and heart disease were all independently associated with higher physical frailty with adjustment for age, physical activity level and ASM. Hypertension was associated with physical frailty in men but not in women. In Cox regression, increased physical frailty was associated with higher 6-year mortality. The impact of metabolic and atherosclerotic risk factors was however only modest after adjustment for age and cognitive function.

CONCLUSION

Metabolic and atherosclerotic diseases and high WHR, was associated with physical frailty, independent of their adverse effect on cognitive function and muscle mass.

Physical frailty predicts future cognitive decline - a four-year prospective study in 2737 cognitively normal older adults

OBJECTIVE

To examine the association between baseline frailty measurements and cognitive function 4 years later.

DESIGN

Prospective observational study.

SETTING

Community.

PARTICIPANTS

Two thousand seven hundred and thirty seven cognitively normal older adults.

MEASUREMENT

The appendicular muscle mass (ASM), hand grip strength, timed chair-stand test, walking speed and step length were measured at baseline. The Mini-mental state examination (MMSE) was administered at baseline and 4 years later.

RESULTS

In men, all baseline frailty measurements, namely, being underweight, lower ASM, weaker grip strength, slower chair-stand test, shorter step length, slower timed walk were significantly associated with a lower MMSE score 4 years afterwards. After adjustment for age, years of education and baseline MMSE score, ASM and timed walk became insignificant. In women, all frailty measurements except underweight and low ASM were significantly associated with MMSE score 4 years later. Moreover, only weaker grip strength persisted to be significant after adjustment for age, years of education and baseline MMSE score.

CONCLUSION

Physical frailty, as represented by being underweight, weaker grip strength, slower chair-stand test, shorter step-length in men and weaker grip strength in women, was associated with cognitive decline over a four year period.

An uncommon cause of recurrent falls in an elderly man

Falls are common among the elderly population. Examinations for the cause of falls are usually mundane, but may be challenging, leading to surprising diagnoses. We report on a previously healthy elderly man who presented with repeated falls and rapidly progressive limitations in mobility, in addition to a stutter. Neuroimaging was particularly helpful for making the diagnosis in this patient.

The effect of diabetes mellitus on age-associated lean mass loss in 3153 older adults

AIMS

Diabetes mellitus may be associated with excessive lean mass loss. Other diabetes-related conditions may also play a role. We assessed body composition changes associated with diabetes in older adults with adjustment for diabetes-related co-morbidities.

METHODS

Three thousand, one hundred and fifty-three community-living adults aged ≥ 65 years were examined for lifestyle factors, diabetes-related medical conditions and body composition by dual energy X-ray absorptiometry at baseline and 4 years later. Body composition changes were compared between participants with diabetes and those without diabetes. Multivariate linear regression was used to examine the relationship between appendicular lean mass loss and confounders.

RESULTS

Appendicular lean mass loss in men with diabetes was two times that of men without diabetes (-1.5% in 'no diabetes' vs. -3.0% in 'diabetes') and in women with diabetes was 1.8 times that of those without diabetes (-1.9% in 'no diabetes' vs. -3.4% in 'diabetes') over 4 years. Men with diabetes also had higher total body mass loss and higher total body fat loss than men without diabetes. Women with diabetes had higher total body mass loss but total body fat loss was similar. After adjusting for age, body mass index, diabetes-related conditions, lifestyle factors and total body mass loss, diabetes remained an independent predictor of appendicular lean mass loss in both men and women.

CONCLUSION

Diabetes was associated with higher body mass loss and higher appendicular lean mass loss in older adults. In men, diabetes was also associated with total body fat loss.

Estimation of stature by measuring fibula and ulna bone length in 2443 older adults

Estimation of Stature by Measuring Fibula and Ulna Bone Length in 2443 Older Adults.

OBJECTIVES

Knee height has been commonly used to estimate stature but may not always be possible in the frail older adults with compromised posture. Measurement of fibula and ulna bone length could be an alternative method. We attempted to develop and validate regression models to predict measured and reported height using age, fibula length, ulna length, hip circumferences and body weight.

DESIGN

A cross-sectional survey.

SETTING

The study was conducted in the Jockey Club Centre for Osteoporosis Care and Control, School of Public Health, The Chinese University of Hong Kong.

PARTICIPANTS

Two thousand four hundred and forty three community-dwelling older Chinese aged from 65 to 98 years were recruited.

MEASUREMENTS

The standing height, fibula length, ulna length, hip circumference and body weight were measured and the reported height was recorded. Three separate multiple linear regression models were developed to predict measured-height and reported-height respectively.

RESULTS

In predicting measured-height by the bone-length model, the mean errors were +0.52 cm (over-estimation) in men and +0.45 cm (over-estimation) in women and the SDs were +/- 3.5 cm in both genders. The 95% limits of agreement were: -6.65 to +7.70 cm for men and -6.59 to +7.49 cm for women.

CONCLUSION

The accuracy and precision of stature estimation by fibula and ulna bone length is comparable to that by knee height. This may be an acceptable alternative method when knee height measurement is difficult or when the knee height caliper is not available.

Can continuous pump feeding reduce the incidence of pneumonia in nasogastric tube-fed patients? A randomized controlled trial

BACKGROUND & AIMS

Continuous pump feeding is often used to reduce aspiration risk in older patients on tube feeding, but its effectiveness in preventing aspiration pneumonia is unproven. A randomized controlled trial was therefore performed to examine the effectiveness of continuous pump feeding in decreasing the incidence of pneumonia in tube-fed older hospital patients.

METHODS

One hundred and seventy eight elderly patients from three convalescence hospitals and one infirmary, on nasogastric tube feeding, were randomly assigned to have intermittent bolus (bolus) or continuous pump (pump) feeding for 4weeks. The primary outcome was the incidence of pneumonia. The secondary outcome was mortality.

RESULTS

Eighty five subjects were randomized into the pump group and 93 in the bolus group. The groups were comparable in age, nutritional and functional status, co-morbidities and history of pneumonia, except that there were more women in the pump group. Within 4weeks, 15 subjects (17.6%) in the pump group and 18 (19.4%) in the bolus group developed pneumonia. Seven subjects (8.2%) in pump group and 13 subjects (14.0%) in bolus group died. There was no significant difference in either pneumonia or death rates between the two groups.

CONCLUSION

Continuous pump feeding did not significantly affect the rates of pneumonia or mortality in tube-fed older hospital patients when compared with intermittent bolus feeding.

MRI: imaging of stomach

The study is to determine the optimal MRI bowel preparation regime for visualization of the stomach anatomy. Eight healthy volunteers were asked to take water, 75% barium and blueberry juice. The image quality and tolerance of different stomach distension regime were evaluated. Blueberry juice gave the best distension, but the signal intensity was not very homogeneous. Taking into account the image quality, tolerability and adverse effects, it is concluded that water is the most desirable oral contrast for MR stomach imaging.

Unusual cases of human myiasis due to Old World screwworm fly acquired indoors in Hong Kong

Myiasis is the infestation of tissue by the larvae of flies. We report eight cases of human myiasis in Hong Kong. All patients were nursing home residents with an average age of 81.8 years. Seven patients were bedridden with advanced dementia. Four patients had pre-existing wounds. Five had poor oral hygiene and four of those were on tube feeding. All of the five patients with poor oral hygiene suffered from oral myiasis. Two patients had vaginal infestations and one had wound myiasis in his diabetic foot ulcer. Seven cases were infested by Chrysomya bezziana, an obligatory parasite that requires living mammalian tissue for its larval development. Larvae of the Calliphoridae family were responsible for the remaining case. Patients were managed with manual removal of larvae and irrigation of the site of infestation with saline. All infestations were nosocomial, being acquired in nursing homes. Carers of the old and debilitated should be made aware of the need for better oral care, especially for those on tube feeding. The use of window screens in nursing homes should be encouraged to reduce the chance of flies entering the vicinity of these patients. Electrocuters could also be mounted indoors to kill flies that do enter.