Nutritional Assessment in Older Adults : MNA® 25 years of a Screening Tool and a Reference Standard for Care and Research; What Next?

A tool to assess nutritional status in older persons was really needed. It took 5 years to design the MNA® (Mini Nutrition Assessment) tool, complete the first validations studies both in Europe and in the U.S. and to publish it. After the full MNA®, the MNA® short form and the self-MNA® have been validated. As well as Chinese and other national MNA® forms. Now more than 2000 clinical research have used the MNA® all over the world from community care to hospital. At least 22 Expert groups included the MNA® in new clinical practice guidelines, national or international registries. The MNA® is presently included in almost all geriatric and nutrition textbook and part of the teaching program for medicine and other health care professional worldwide. The urgent need is to target the frail older adults more likely to have weight loss and poor appetite and to prevent frailty and weight loss in the robust. We present in this paper the review of 25 years of clinical research and practice using the MNA® worldwide.

Frailty and Nutrition: What We Have Learned from Research and Clinical Practice on the Mini Nutritional Assessment

In this short communication, we review the relationship between frailty and malnutrition risk in the elderly. Frailty is a term used for elderly at increased risk of adverse outcomes, including disability, falls, hospitalization, need for long-term care, and mortality. The Mini Nutritional Assessment (MNA) was designed and validated in a series of studies to assess nutritional status of elderly, as integral part of the comprehensive geriatric assessment, with a 2-steps screening process; when the MNA-SF classify a person at risk, the full MNA should be completed. The MNA and MNA-SF are sensitive, specific, and accurate in identifying nutrition risk. Increased risk of malnutrition, a common condition in the elderly, is closely associated with many potential contributors of frailty. The maintenance of optimal physical and cognitive performances depends on the early screening of critical conditions to develop preventive targeted interventions; the MNA supports such preventive action.

Health and nutrition promotion program for patients with dementia (NutriAlz): cluster randomized trial

OBJECTIVE

To assess the effectiveness of health and nutrition program (NutriAlz) versus usual care on functional level in elderly people with dementia living at home, as well as on clinical practice related to nutrition and on the caregiver's burden.

DESIGN

Cluster randomized multi-centre study with one-year follow-up.

SETTING

11 Alzheimer outpatients and day care centres (Barcelona, Spain).

PARTICIPANTS

Nine hundred and forty six home-living Alzheimer patients with identified caregiver were consecutively recruited (intervention group: 6 centres, 448 patients vs control group: 5 centres, 498 patients).

INTERVENTION

The intervention was a teaching and training intervention on health and nutrition program, NutriAlz, directed both to physician and main caregiver, as well as persons affected by Alzheimer's disease or other dementias, including a standardised protocol for feeding and nutrition.

MAIN OUTCOME MEASURES

The main outcome measure was the reduction in the loss of autonomy (Activities of daily living (ADL/IADL) scales) assessed at 6 and 12 months. Secondary outcomes measures were Improvement in nutritional status (Mini Nutritional Assessment (MNA), BMI, and weight changes), and caregiver burden (Zarit scale).

RESULTS

The one-year assessment was completed for 293 patients (65.4%) in the intervention group and 363 patients (72.9%) in the control group (usual care). The annual rate of ADL change was -0.83 vs -0.62 (p=0.984), and the caregiver's subjective burden 0.59 vs 2.36 (p=0.681) in intervention and control group, respectively. MNA, however, showed an improvement (+0.46 vs -0.66, p=0.028), suggesting an effective nutritional behaviour.

CONCLUSION

The NutriAlz program had no effect on functional decline in Alzheimer disease patients living at home over one year, but reduced the risk for malnutrition, as recommendations concerning diet and exercise were provided.

Aging, modulation of food intake and spatial memory: a longitudinal study

This longitudinal study investigates the effects of different long-term dietary treatments on spatial memory in rats. An ad libitum group, a group of rats fasting two days a week, and a group fed 70% of the ad libitum food intake were studied at 6, 12, 19 and 24 months of age. Spatial memory was tested in the Morris water maze. Three test situations were presented: a spatial learning test, a retrieval test, and a reversal test. In the first test, the animals had to find a submerged platform which remained in a fixed location throughout the study. Dietary treatment of rats had no effect on the performances at any of the ages tested. In the retrieval test, rats had to search for the location of the trained platform which had been removed for two minutes. All three groups searched at the correct location at 12 months of age. However, at 19 and 24 months of age, the ad libitum and fasting groups showed a significant deterioration in performance. This was not the case for the 70% restricted rats. In the reversal test, the platform which had been at the same location for the spatial learning test was moved into the opposite quadrant. The 70% restricted 24 month old rats adapted to the new situation by rapidly changing their swimming pattern. Again this was not the case for the two other groups. In conclusion, our study shows that food restriction is beneficial to old rats tested throughout their life in the Morris water maze, especially in the retrieval and reversal tests. Our study also indicates that food restriction and fasting do not have the same effect on the spatial memory in the old rats although this needs to be substantiated with further inquiries.

Validation of the Mini Nutritional Assessment short-form (MNA-SF): a practical tool for identification of nutritional status

OBJECTIVE

To validate a revision of the Mini Nutritional Assessment short-form (MNA(R)-SF) against the full MNA, a standard tool for nutritional evaluation.

METHODS

A literature search identified studies that used the MNA for nutritional screening in geriatric patients. The contacted authors submitted original datasets that were merged into a single database. Various combinations of the questions on the current MNA-SF were tested using this database through combination analysis and ROC based derivation of classification thresholds.

RESULTS

Twenty-seven datasets (n=6257 participants) were initially processed from which twelve were used in the current analysis on a sample of 2032 study participants (mean age 82.3y) with complete information on all MNA items. The original MNA-SF was a combination of six questions from the full MNA. A revised MNA-SF included calf circumference (CC) substituted for BMI performed equally well. A revised three-category scoring classification for this revised MNA-SF, using BMI and/or CC, had good sensitivity compared to the full MNA.

CONCLUSION

The newly revised MNA-SF is a valid nutritional screening tool applicable to geriatric health care professionals with the option of using CC when BMI cannot be calculated. This revised MNA-SF increases the applicability of this rapid screening tool in clinical practice through the inclusion of a "malnourished" category.

Health and nutritional promotion program for patients with dementia (NutriAlz Study): design and baseline data

BACKGROUND

There is a lack of data on global weight loss prevention programs for patients with dementia or clear evidence about their impact on a functional level, caregiver burden or the use of healthcare and social resources. NutriAlz is a socio-educative and nutritional intervention program to prevent weight loss and loss of function in dementia patients.

STUDY DESIGN AND METHODS

A cluster randomized multi-centre study, which will allow the comparison of a group benefiting from the intervention with a control group after a year of monitoring. Patients were recruited from 11 hospitals in the ambulatory diagnostic units and day care centres. The baseline interview include: sociodemographic and socioeconomic variables (age, gender, educational level, marital status); diagnostic, treatments, MMS, a list of comorbid conditions; activities of daily living (ADL, IADL), Zarit Scale, brief-NPI, Cornell scale and nutritional status as measured by the Mini Nutritional Assessment. All participants or their family signed the inform consent form.

BASELINE CHARACTERISTICS

Total of 946 patients were included, with a mean (+/- SD) of 79 +/- 7.3 year of age; 68,1 % were women; 44,9% lives with their partner, only 3% lives alone; 79.8% had Alzheimer's dementia, 5.25 +/- 3.0 years since symptoms of dementia and 2.8 +/- 2.11 years since diagnosis. Mean MMSE score was 15.4 +/- 6.2; mean weight was 64.4 +/- 12.5 kg; mean BMI was 27.0 +/- 4.5 (with 3% below 19, 5% between 19-21, 10% between 21-23, and 82% above 23). Mean ADL without difficulties was 3.2 +/- 2.1; mean IADL without difficulties was 0.7 +/- 1.6; mean number of symptoms in the NPI was 4.4 +/- 2.59, with severity score of 7.9 +/- 5.9 and distress score of 11.3 +/- 9.0; mean Zarit scale was 27.4 +/- 15.5; mean MNA was 23.2 +/- 3.5 with 5 % as malnourished, 32 % at risk of malnutrition, and 63 % with adequate nutritional status.

Systemic inflammatory markers in older persons: the effect of oral nutritional supplementation with prebiotics

OBJECTIVE

To evaluate the effect of oral nutritional supplementation with and without oligosaccharides on gut bacteriology, in particular the bifidogenic flora, and on immunology and inflammatory parameters in older persons at risk of malnutrition.

DESIGN

Prospective, randomized, double-blind, controlled study.

SETTING

Division of Geriatric Medicine, St. Louis University, Missouri, United States.

PARTICIPANTS

Seventy-four community dwelling elderly and/or nursing home subjects (age superior 70 y; 84 +/- 7 years) either undernourished or at risk of undernutrition.

INTERVENTION

Daily liquid supplements, with (1.3 g/250 ml) and without oligosaccharides (OS) for 12 weeks.

MEASUREMENTS

Nutritional evaluation, serum immunoglobulins, lymphocyte subsets, various cytokines and the endotoxin soluble receptor CD14 (sCD14) in serum, and cytokines specific mRNA in peripheral blood mononuclear cells at baseline and 12 weeks, and fecal bacteriologicy.

RESULTS

Specific mRNA extracted from blood leucocytes showed a different level of pro-inflammatory gene activation: TNF-alpha mRNA and IL-6 mRNA diminished in the OS group after 12 weeks, while no changes were detected in the control group (P=0.05 and P=0.04 respectively). Serum levels of sCD14, a product shed by activated macrophages, decreased only in the OS group without reaching statistical significance (P=0.08). No significant differences were detected in the fecal gut flora or in the nutritional parameters.

CONCLUSIONS

This study shows that the administration of supplements in older persons at risk of malnutrition may benefit from the addition of prebiotics that can improve the low noise inflammatory process frequently observed in this population.

Overview of the MNA--Its history and challenges

The Mini Nutritional Assessment (MNA) is a simple tool, useful in clinical practice to measure nutritional status in elderly persons. From its validation in 1994, the MNA has been used in hundreds of studies and translated into more then 20 languages. It is a well-validated tool, with high sensitivity, specificity, and reliability. An MNA score > or = 24 identifies patients with a good nutritional status. Scores between 17 and 23.5 identify patients at risk for malnutrition. These patients have not yet started to lose weight and do not show low plasma albumin levels but have lower protein-calorie intakes than recommended. For them, a multidisciplinary geriatric intervention is needed, which takes into account all aspects that might interfere with proper alimentation and, when necessary, proposes therapeutic interventions for diet or supplementation. If the MNA score is less than 17, the patient has protein-calorie malnutrition. It is important at this stage to quantify the severity of the malnutrition (by measuring biochemical parameters like plasma albumin or prealbumin levels, establishing a 3- day record of food intake, and measuring anthropometric features like weight, BMI, arm circumference and skin folds). Nutritional intervention is clearly needed and should be based on achievable objectives established after a detailed comprehensive geriatric assessment. The MNA has been shown to be useful for nutritional intervention follow-up as well. The MNA can help clinicians design an intervention by noting where the patient loses points when performing the MNA. Moreover, when a nutritional intervention is successful, the MNA score increases. The MNA is recommended by many national and international clinical and scientific organizations. It can be used by a variety of professionals, including physicians, dietitians, nurses or research assistants. A short screening version (MNA-SF) has been developed, which, if positive, indicates the need to complete the full MNA. It takes less than 4 minutes to administer the MNA-SF and between 10 and 15 minutes for the full MNA.

The Mini Nutritional Assessment (MNA) review of the literature--What does it tell us?

To review the literature on the MNA to Spring 2006, we searched MEDLINE, Web of Science and Scopus, and did a manual search in J Nutr Health Aging, Clin Nutr, Eur J Clin Nutr and free online available publications.

VALIDATION AND VALIDITY

The MNA was validated against two principal criteria, clinical status and comprehensive nutrition assessment using principal component and discriminant analysis. The MNA shortform (MNA-SF) was developed and validated to allow a 2-step screening process. The MNA and MNA-SF are sensitive, specific, and accurate in identifying nutrition risk.

NUTRITIONAL SCREENING

The prevalence of malnutrition in community-dwelling elderly (21 studies, n = 14149 elderly) is 2 +/- 0.1% (mean +/- SE, range 0- 8%) and risk of malnutrition is 24 +/- 0.4% (range 8-76%). A similar pattern is seen in out-patient and home care elderly (25 studies, n = 3119 elderly) with prevalence of undernutrition 9 +/- 0.5% (mean +/- SE, range 0-30%) and risk of malnutrition 45 +/- 0.9% (range 8-65%). A high prevalence of undernutrition has been reported in hospitalized and institutionalized elderly patients: prevalence of malnutrition is 23 +/- 0.5% (mean +/- SE, range 1- 74%) in hospitals (35 studies, n = 8596) and 21 +/- 0.5% (mean +/- SE, range 5-71%) in institutions (32 studies, n = 6821 elderly). An even higher prevalence of risk of malnutrition was observed in the same populations, with 46 +/- 0.5% (range 8-63%) and 51 +/- 0.6% (range 27-70%), respectively. In cognitively impaired elderly subjects (10 studies, n = 2051 elderly subjects), detection using the MNA, prevalence of malnutrition was 15 +/- 0.8% (mean +/- SE, range 0-62%), and 44 +/- 1.1% (range 19-87%) of risk of malnutrition.

CHARACTERISTICS

The large variability is due to differences in level of dependence and health status among the elderly. In hospital settings, a low MNA score is associated with an increase in mortality, prolonged length of stay and greater likelihood of discharge to nursing homes. Malnutrition is associated with functional and cognitive impairment and difficulties eating. The MNA(R) detects risk of malnutrition before severe change in weight or serum proteins occurs.

NUTRITIONAL INTERVENTION

Intervention studies demonstrate that timely intervention can stop weight loss in elderly at risk of malnutrition or undernourished and is associated with improvements in MNA scores. The MNA can also be used as a follow up assessment tool.

CONCLUSION

The MNA is a screening and assessment tool with a reliable scale and clearly defined thresholds, usable by health care professionals. It should be included in the geriatric assessment and is proposed in the minimum data set for nutritional interventions.

Nutritional status using the Mini Nutritional Assessment questionnaire and its relationship with bone quality in a population of institutionalized elderly women

Malnutrition, a risk factor for osteoporotic fractures, is frequent in elderly people and, is underdiagnosed and undertreated. There are only few studies on the nutritional status of elderly people in Europe. The Mini Nutritional Assessment (MNA) is a non invasive and validated questionnaire to evaluate nutritional status in elderly people, classified in three groups: 1 degree score < 17: malnourished, 2 degrees score >17 and < 24: at risk of malnutrition, 3 degrees score >24: well-nourished, with a maximum of 30 points. Quantitative ultrasound of bone (QUS) is a method for assessing quality of bone which can be easily performed in nursing homes. Therefore, these two tests allowed to study the relationships between nutritional status and ultrasonic parameters of bone in 78 institutionalized women aged 86 +/- 6 years, living in 11 nursing homes around Lausanne (Switzerland). All were assessed by the MNA, had a measurement of the tricipital skin fold and of the grip strength. Functional status was evaluated by the scale "Activity of Daily Living" (ADL), and serum albumin level was measured when permitted. All had QUS of the calcaneus (with an Achilles, GE Lunar). The measured parameters are the Broadband Ultrasound Attenuation (BUA), attenuation of a band of ultrasonic frequencies through the medium, expressed in dB/MHz, and the Speed of Sound (SOS), speed of the ultrasounds through the medium, expressed in m/s. A third parameter, the stiffness index (SI), expressed as a percentage of the values obtained by the manufacturer in a young population and derived from BUA and SOS, was calculated automatically : SI = (0.67xBUA) + (0.28xSOS) - 420, expressed in percent compared to a young adult population (%YA). Fifteen percent of the women were undernourished and 58% were at risk of malnutrition. As expected, compared with the well-nourished minority, undernourished subjects had significant lower body mass index (BMI), tricipital skin fold (TSF), ADL score and albumin level (p < 0,01). The subjects "at risk of malnutrition" had significant lower BMI, ADL score (p < 0.01), tricipital skin fold and serum albumin (p < 0.05). Ultrasound parameters were low independently of the nutritional status. MNA score correlated significantly with tricipital skin fold (r = 0.508, p < 0.01), ADL (r = 0.538, p < 0.01) and albumin serum level (r = 0.409, p = 0.01). There was a trend for a correlation between the MNA and the ultrasound parameter BUA (r = 0.207, p = 0.07), whereas no correlation was found with SOS and SI. A multivariate analysis showed that tricipital skin fold and ADL explained 61% of the variance of the MNA. In conclusion, using simple and non invasive methods, this study showed that malnutrition and osteoporosis are frequent in institutionalized elderly persons in our country, and the ultrasound parameters are influenced by many others factors in addition to nutrition, especially at this age and in elderly residents of nursing homes.

Anorexia of aging, leptin, and the Mini Nutritional Assessment

In this chapter we have reviewed the evidence for physiological anorexia of aging and stressed that its pathophysiology involves both central and peripheral mechanisms. Early satiation in the older person appears to involve signals predominantly arising in the stomach. The increased feeling of satiety in older persons is mainly related to changes in the central feeding drive, in particular a decrease in the opioid rewarding properties for fatty foods. Increased cytokines, secondary to inflammatory conditions which are common in old age, may further increase the anorexia seen in older persons. Leptin, the fat hormone, is an excellent indicator of fat mass in women, in whom leptin concentrations correlate with the MNA. In men, testosterone inhibits leptin, and the fall in testosterone with age results in an increase in leptin concentrations. In males the MNA is not related to leptin concentrations. Finally, we have examined the interrelation of two nutritional screening indices, MNA and SCALES. The two indices were well correlated and were both predictive of poor basic function. We conclude that the MNA is an excellent predictor of nutritional status. These findings suggest that malnutrition is a major predictor of frailty or the "failure to thrive" syndrome in older persons. Depression is a major cause of poor nutritional status in older persons.

Screening for undernutrition in geriatric practice: developing the short-form mini-nutritional assessment (MNA-SF)

BACKGROUND

The Mini-Nutritional Assessment (MNA) is a validated assessment instrument for nutritional problems, but its length limits its usefulness for screening. We sought to develop a screening version of this instrument, the MNA-SF, that retains good diagnostic accuracy.

METHODS

We reanalyzed data from France that were used to develop the original MNA and combined these with data collected in Spain and New MEXICO: Of the 881 subjects with complete MNA data, 151 were from France, 400 were from Spain, and 330 were from New MEXICO: Independent ratings of clinical nutritional status were available for 142 of the French subjects. Overall, 73.8% were community dwelling, and mean age was 76.4 years. Items were chosen for the MNA-SF on the basis of item correlation with the total MNA score and with clinical nutritional status, internal consistency, reliability, completeness, and ease of administration.

RESULTS

After testing multiple versions, we identified an optimal six-item MNA-SF total score ranging from 0 to 14. The cut-point score for MNA-SF was calculated using clinical nutritional status as the gold standard (n = 142) and using the total MNA score (n = 881). The MNA-SF was strongly correlated with the total MNA score (r = .945). Using an MNA-SF score of > or = 11 as normal, sensitivity was 97.9%, specificity was 100%, and diagnostic accuracy was 98.7% for predicting undernutrition.

CONCLUSIONS

The MNA-SF can identify persons with undernutrition and can be used in a two-step screening process in which persons, identified as "at risk" on the MNA-SF, would receive additional assessment to confirm the diagnosis and plan interventions.

Relationships between nutritional markers and the mini-nutritional assessment in 155 older persons

OBJECTIVE

To investigate the relationships between nutritional status measured by a comprehensive nutritional assessment including anthropometric measurements, nutritional biological markers, evaluation of dietary intake, and the Mini-Nutritional Assessment (MNA) nutrition screening tool.

DESIGN

A prospective study.

PARTICIPANTS

One hundred fifty-five older subjects (53 men and 102 women; mean age = 78 years; range = 56-97 years). These participants were hospitalized in a geriatric evaluation unit (n = 105) or free living in the community (n = 50).

MEASUREMENT

Weight, height, knee height, midarm and calf circumferences, triceps and subscapular skinfolds, albumin, transthyretin (prealbumin), transferrin, ceruloplasmin, C-reactive protein, alpha1-acid glycoprotein, cholesterol, vitamins A, D, E, B1, B2, B6, B12, folate, copper, zinc, a 3 day food record combined with a food-frequency questionnaire; the MNA nutritional screening.

RESULTS

The MNA scores have been found to be significantly correlated to nutritional intake (P < .05 for energy, carbohydrates, fiber, calcium, vitamin D, iron, vitamin B6, and vitamin C), anthropometric and biological nutritional parameters (P < .001 for albumin, transthyretin, transferrin, cholesterol, retinol, alpha-tocopherol, 25-OH cholecalciferol zinc). An MNA score between 17 and 23.5 can identify those persons with mild malnutrition in which nutrition intervention may be effective.

CONCLUSIONS

The MNA is a practical, noninvasive, and cost-effective instrument allowing for rapid nutritional evaluation and effective intervention in frail older persons.

Protein-energy oral supplementation in malnourished nursing-home residents. A controlled trial

OBJECTIVES

To validate a nutritional intervention programme for elderly people living in nursing homes.

DESIGN

In a prospective, randomized, controlled study of 88 residents, we determined nutritional status at day 0 and day 60 using a record of dietary intake, anthropometry, hand-grip strength and mini-nutritional assessment. Dietary intake, grip strength and body weight were also recorded at day 30. We divided subjects into four groups according to their mini-nutritional assessment score. Those with a score 24 received no oral supplementation. Those at risk of malnutrition (with a score of 17-23.5) were randomized to oral supplementation. Those with a score <17 received oral supplementation. We recorded the amount of oral supplements consumed daily.

RESULTS

Compliance with oral supplementation was good, and daily intake averaged about 400 kcal. The total energy intake on day 60 was significantly higher in both of the groups that received supplements. Following supplementation, most subjects at risk of malnutrition improved their mini-nutritional assessment score and increased their weight (by 1.4 +/- 0.5 kg). Neither the mini-nutritional assessment score nor weight improved in subjects at risk of malnutrition who did not receive supplements. Supplementation in the malnourished group resulted in a mean mini-nutritional assessment score increase (from 13.9 +/- 2.6 to 17.1 +/- 3.9) and a mean weight gain of 1.5 +/- 0.4 kg.

CONCLUSION

Oral nutritional supplements are well accepted and result in increased daily protein and energy intake, body weight and nutritional status in most malnourished patients and in those at risk of malnutrition.

The Mini Nutritional Assessment (MNA) and its use in grading the nutritional state of elderly patients

The Mini Nutritional Assessment (MNA) has recently been designed and validated to provide a single, rapid assessment of nutritional status in elderly patients in outpatient clinics, hospitals, and nursing homes. It has been translated into several languages and validated in many clinics around the world. The MNA test is composed of simple measurements and brief questions that can be completed in about 10 min. Discriminant analysis was used to compare the findings of the MNA with the nutritional status determined by physicians, using the standard extensive nutritional assessment including complete anthropometric, clinical biochemistry, and dietary parameters. The sum of the MNA score distinguishes between elderly patients with: 1) adequate nutritional status, MNA > or = 24; 2) protein-calorie malnutrition, MNA < 17; 3) at risk of malnutrition, MNA between 17 and 23.5. With this scoring, sensitivity was found to be 96%, specificity 98%, and predictive value 97%. The MNA scale was also found to be predictive of mortality and hospital cost. Most important it is possible to identify people at risk for malnutrition, scores between 17 and 23.5, before severe changes in weight or albumin levels occur. These individuals are more likely to have a decrease in caloric intake that can be easily corrected by nutritional intervention.

[Malnutrition in the elderly: the Mini Nutritional Assessment (MNA)]

Frail elderly in the community, in nursing homes or in hospitals are at increased risk of malnutrition. In many instances, their existing nutritional disorders go unrecognised and adversely affect their health, ability to overcome disease, and so is associated with poor clinical outcome. The prevalence of malnutrition ranges from 5-10% in free-living elderly to 30-85% in homebound, nursing home, and hospitalised elderly. Possibilities exist to prevent or correct this malnutrition, but have not been frequently used until now due to the lack of a specific validated tool to screen for malnutrition. The goal of the Mini Nutritional Assessment (MNA) is to determine who is at risk of malnutrition, and hence to permit early nutritional intervention. It has been designed for easy use by general practitioners as well as health professionals involved in admitting patients to hospitals and nursing homes. The test, which comprises simple measurements and a brief questionnaire, can be performed in about 10 minutes. It involves: anthropometric assessment (weight, height and weight loss) general assessment (lifestyle, medication and mobility) dietary assessment (number of meals, food and fluid intake, autonomy of eating self assessment (self-perception of health and nutrition). The MNA has now been validated in three studies involving more than 600 elderly individuals, from the very frail to the very active in free-living and long-term care environments. The MNA was validated against a clinical evaluation and a comprehensive nutritional assessment. It can classify the elderly as well-nourished, undernourished, or at risk of malnutrition. The MNA can be an important tool in evaluating the risk of malnutrition in the elderly, if integrated into geriatric assessment programs.

Mental health: minimental state examination and geriatric depression score of elderly Europeans in the SENECA study of 1993

OBJECTIVE

Assessment of the mental health of the European elderly and its correlations with micronutrient plasma levels, education and ability to carry out activities of daily living.

DESIGN

Cross-sectional study.

SETTING

Eleven small towns in nine European countries.

SUBJECTS

Randomised sample of 880 subjects of both sexes born in the period 1913 to 1918, stratified according to age and sex.

INTERVENTIONS

The mental status was assessed by means of the Mini-Mental State Examination (MMSE) and the 15-item Geriatric Depression Scale (GDS).

RESULTS

The overall mean MMSE score was 26.7 and this was also the mean for both sexes. MMSE scores below 23 were found in 8.5% of the men and 10.9% of the women. The overall mean GDS score was 3.9, 3.2 for the men and 4.6 for the women. GDS scores above the cut-off of 5 were found in 11.6% of the men and 27.5% of the women. There were many correlations between the MMSE and the GDS scores and education, Activities of Daily Living scores, subjective health and plasma micronutrient levels, particularly the carotenoids. No geographical pattern of the distribution of MMSE and GDS scores was discernible.

CONCLUSIONS

The overall cognitive function of these elderly subjects aged 74 to 79 years was on the whole well preserved. The GDS scores suggest that the prevalence of depression was high in this sample. Education and higher plasma levels of certain vitamins and carotenoids appear to be associated with lower risk of developing dementia.

Techniques of assessing muscle mass and function (sarcopenia) for epidemiological studies of the elderly

For epidemiological studies, reliable and valid measurements or indices of muscle mass are needed to screen for those elderly persons at risk for sarcopenia, and to determine the prevalence of these conditions on a national level. The methods more suitable for field or epidemiological settings are anthropometry, bioelectrical impedance, and grip strength. These field methods, while reliable, have limited demonstrated validity in their application to the elderly and are restricted by the limited functional capabilities of the elderly, which decrease with age. Epidemiological studies of the elderly need to include sufficient numbers of persons of different ethnic backgrounds, and at the older ages. For an epidemiological study of the elderly today, one also needs to select the categories of elderly persons to be included in such studies: healthy, sick, very old, handicapped, level of functional status, etc., because relationships among variables can have different statistical and biological associations. Future work should be directed at improving the design and methodology of epidemiological and serial studies so as to maximize the numbers and categories of elderly persons who can be studied.

Identification of several isoforms of T-kininogen expressed in the liver of aging rats

We have previously shown that senescent Sprague-Dawley rats have significantly increased levels of kininogen (KG) mRNA and protein, when compared with younger counterparts. In the rat, five different isoforms of kininogen have been identified: high-molecular-weight K-kininogen, low-molecular-weight K-kininogen, and T1 alpha, T1 beta, and T2 kininogens. Several of these isoforms have been shown to differ in their biological properties. It was therefore considered relevant to establish which of these isoforms are expressed in the liver of old rats. To this end, we have isolated and sequenced nine independent cDNA clones from a library constructed using liver mRNA from healthy senescent rats. Predicted protein sequences indicate the presence of T-kininogens only. The relative lack of induction of K-kininogens during aging was further confirmed by RNA hybridization experiments. The nucleotide sequences reveal a microheterogeneity of silent polymorphisms, suggesting the presence and expression of several different alleles of the genes. From our data we conclude that (i) Several isoforms of T-KG are expressed in the liver of senescent Sprague-Dawley rats and (ii) T1 kininogens appear to be the most highly represented T-KG mRNA species in old rat livers.

Phase I and phase II xenobiotic reactions and metabolism of the food-borne carcinogen 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline in aggregating liver cell cultures

Aggregating fetal liver cell cultures were tested for their ability to metabolize xenobiotics using ethoxycoumarin-O-deethylase (ECOD), as marker of phase I metabolism, and glutathione S-transferase (GST), as marker for phase II reactions. Significant basal activities, stable over 14 days in culture were measured for both ECOD and GST activities. The prototype cytochrome P450 inducers, 3-methylcholanthrene (3-MC) and phenobarbital (PB), increased ECOD and GST activities reaching an optimum 7 days after culturing, followed by a decline in activity. This decline was partially prevented by 1% dimethyl sulfoxide (DMSO) added chronically to the culture medium. DMSO was also found to induce ECOD activity and to a lesser extent GST activity. Furthermore, it potentiated in a dose-dependent manner the induction of ECOD by PB. The food-borne carcinogen 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) is metabolically transformed through a number of pathways in vivo. It was therefore used to examine the metabolic capacity in fetal and adult liver cell aggregates. Metabolism of MeIQx was mainly through N2-conjugation, resulting in formation of the N2-glucuronide and sulfamate conjugates for non-induced fetal liver cells. These metabolites were also found in large amounts in non-induced adult liver cells. Low levels of cytochrome P450-mediated ring-hydroxylated metabolites were detected in both non-induced fetal and adult liver cells. After induction with arochlor (PCB) or 3-MC, the major pathway was ring-hydroxylation (cytochrome P450 dependent), followed by conjugation to beta-glucuronic or sulfuric acid. The presence of the glucuronide conjugate of N-hydroxy-MeIQx, a mutagenic metabolite, suggested an induction of P450 CYP1A2. The metabolism of MeIQx by liver cell aggregates is very similar to that observed in vivo and suggests that aggregating liver cell cultures are a useful model for in vitro metabolic studies in toxicology.

Type 1 plasminogen activator inhibitor is not an acute phase reactant in rats. Lack of IL-6- and hepatocyte-dependent synthesis

The contributing role of hepatocytes and IL-6 in the acute phase-like elevation of plasma type 1 plasminogen activator inhibitor (PAI-1) in vivo is not known. We addressed this question by comparing the effects of two inflammatory stimuli known to increase plasma concentrations of IL-6 on the plasma concentrations and site of synthesis of PAI-1 and cysteine proteinase inhibitor (CPI) in rats. Subcutaneous injection of turpentine results in a sustained increase in plasma IL-6 and CPI Ag levels over a 24-h period. In contrast, plasma PAI-1 activity was not altered by turpentine treatment. Northern blot analysis of poly(A)+ mRNA extracted from freshly isolated hepatocytes of saline- or turpentine-treated animals demonstrated induction of CPI mRNA expression but failed to detect basal or induced PAI-1 or IL-6 mRNA expression. However, PAI-1 mRNA was detected in rat hepatocytes in primary culture for 24 h and was induced by dexamethasone. Intravenous infusion of bacterial LPS (4 mg/kg) induced a sustained increase in plasma CPI Ag and transient increases in plasma IL-6 and PAI-1. Northern blot analysis of freshly isolated, fractionated liver cells indicated that LPS treatment (3 h) induced PAI-1 mRNA expression most significantly in the endothelial and Kupffer cell fractions. IL-6 mRNA expression was induced in Kupffer cells and CPI mRNA was induced in hepatocytes. Immunocytochemical analysis revealed LPS-induced accumulation of PAI-1 Ag associated with the vascular endothelium, subendothelial matrix, and sinusoidal lining cells. Our results indicate that PAI-1 mRNA is not significantly expressed by rat hepatocytes in vivo and that plasma PAI-1 levels are not influenced by increased IL-6 expression in Kupffer cells or in plasma.

Type 1 plasminogen activator inhibitor is not an acute phase reactant in rats. Lack of IL-6- and hepatocyte-dependent synthesis

The contributing role of hepatocytes and IL-6 in the acute phase-like elevation of plasma type 1 plasminogen activator inhibitor (PAI-1) in vivo is not known. We addressed this question by comparing the effects of two inflammatory stimuli known to increase plasma concentrations of IL-6 on the plasma concentrations and site of synthesis of PAI-1 and cysteine proteinase inhibitor (CPI) in rats. Subcutaneous injection of turpentine results in a sustained increase in plasma IL-6 and CPI Ag levels over a 24-h period. In contrast, plasma PAI-1 activity was not altered by turpentine treatment. Northern blot analysis of poly(A)+ mRNA extracted from freshly isolated hepatocytes of saline- or turpentine-treated animals demonstrated induction of CPI mRNA expression but failed to detect basal or induced PAI-1 or IL-6 mRNA expression. However, PAI-1 mRNA was detected in rat hepatocytes in primary culture for 24 h and was induced by dexamethasone. Intravenous infusion of bacterial LPS (4 mg/kg) induced a sustained increase in plasma CPI Ag and transient increases in plasma IL-6 and PAI-1. Northern blot analysis of freshly isolated, fractionated liver cells indicated that LPS treatment (3 h) induced PAI-1 mRNA expression most significantly in the endothelial and Kupffer cell fractions. IL-6 mRNA expression was induced in Kupffer cells and CPI mRNA was induced in hepatocytes. Immunocytochemical analysis revealed LPS-induced accumulation of PAI-1 Ag associated with the vascular endothelium, subendothelial matrix, and sinusoidal lining cells. Our results indicate that PAI-1 mRNA is not significantly expressed by rat hepatocytes in vivo and that plasma PAI-1 levels are not influenced by increased IL-6 expression in Kupffer cells or in plasma.

Serum T-kininogen levels increase two to four months before death

We have reported an accumulation of T-kininogen mRNA in the liver of aging Sprague-Dawley rats. T-kininogen is a cysteine proteinase inhibitor. Since a disruption of the intracellular protein degradation machinery is known to occur during senescence, we wished to further define the role of this protein in the aging process. As a first step, we have measured T-kininogen levels both in serum and within the liver. We have found that serum protein levels are indeed augmented during senescence, although not as dramatically as the mRNA (2.5-fold versus 8.3-fold). Immunocytochemistry, as well as Western blot analysis suggests that this is due to the presence of T-kininogen within hepatic cells in aged rats. Life-long dietary restriction, a known age-prolonging treatment, decreases the overexpression of the protein in 24-month-old rats. Later, diet-restricted animals still show an increased expression from the gene, the effect being delayed but not abolished by dietary manipulation. Interestingly, a longitudinal study indicated the existence of a positive correlation between the time of increase of serum T-kininogen and the time of death of the animal. Serum T-kininogen was found to increase 2.5-4 months before death.

T-kininogen gene expression is induced during aging

We have constructed a cDNA library from senescent (24-month-old) rat liver mRNA and, by differential screening, have selected clones corresponding to mRNA species with increased abundance in aging rats. Direct sequencing of the inserts indicated that most of the clones (9 of 10) contained sequences coding for T-kininogen, also called major acute-phase protein, cysteine protease inhibitor, or thiostatin. Nuclear elongation experiments showed that the increase in mRNA concentration was controlled at the transcriptional level. RNase mapping and S1 analysis indicated that the age-dependent induction operated preferentially at one of the three transcriptional start sites of the gene(s). The acute-phase reaction (inflammation) is known to also induce these genes at the level of transcription; however, two of the three start sites are induced by inflammation. Transcription from one of these sites was induced by both phenomena, aging and inflammation.

Aggregate cultures of foetal rat liver cells: development and maintenance of liver gene expression

Rotation-mediated aggregate cultures of foetal rat liver cells were prepared and grown in a chemically defined medium. Their capacity for cellular organisation and maturation was studied over a culture period of 3 wk by using both morphologic and biochemical criteria. It was found that within each aggregate, distinct liver cell types were present and attained their normal, differentiated phenotype. Parenchymal cells formed small acini with a central lumen. Within the first 2 wk in culture, albumin and ferritin mRNA levels were maintained, while the alpha-fetoprotein mRNA levels decreased, and tyrosine aminotransferase (TAT) gene expression increased. No significant response to glucocorticoids was observed in early cultures, whereas after 3 wk a marked increase in TAT mRNA levels was elicited by dexamethasone and glucagon (additive stimulatory effects). The results show that foetal rat liver cells cultured in a chemically defined medium are able to rearrange themselves into histotypic structures, and display a developmental pattern of gene expression comparable to that of perinatal rat liver in vivo. This culture system offers therefore a useful model to study the development and function of liver cells.

The effect of age on the induction of tyrosine aminotransferase and tryptophan oxygenase genes by physiological stress

Expression of the genes coding for tyrosine aminotransferase and tryptophan oxygenase in rats is induced in response to cold stress. We have studied the effect of ageing on this induction. The induction of tyrosine aminotransferase activity in young adult rats (10 months) was about twice that observed with old rats (25 months). This difference between the two age groups was also observed when the steady-state level of tyrosine aminotransferase mRNA was measured by hybridization with a specific DNA probe. However, when the transcription rate of the gene was measured by in vitro elongation of nascent RNA in isolated nuclei, no difference was detected. In contrast to the results with tyrosine aminotransferase, induced tryptophan oxygenase enzyme and mRNA levels did not show an age-dependent difference. These results suggest that there is, with ageing, an impairment in post-transcriptional regulation of the synthesis of tyrosine aminotransferase. The regulation of tryptophan oxygenase, on the other hand, is similar in the two age groups.

Pretranslational regulation of tyrosine aminotransferase and phosphoenolpyruvate carboxykinase (GTP) synthesis by glucagon and dexamethasone in adult rat hepatocytes

The regulation of synthesis of the gluconeogenic cytosolic enzyme phosphoenolpyruvate carboxykinase (PEPCK) and of tyrosine aminotransferase (TAT) by glucagon and glucocorticoid hormones was studied in hepatocytes maintained in suspension culture for 7 h. Specific antibodies were used to measure relative rates of enzyme synthesis after pulse-labelling of the cells with [3H]leucine or [35S]methionine. Concomitantly, amounts of mRNA were quantified after translation in vitro in a reticulocyte lysate and specific immunoprecipitation of the proteins. Glucagon stimulated the rate of synthesis of PEPCK by 4-6-fold and that of TAT by 6-8-fold in 2h. In contrast, dexamethasone had little effect on PEPCK synthesis, whereas it increased TAT synthesis by 5-9-fold. When used in combination, the two hormones displayed additive effects on TAT synthesis, whereas the glucocorticoid hormone strongly potentiated stimulation of PEPCK synthesis by glucagon. In every instance, changes in rates of synthesis of the two enzymes were totally accounted for by increases in amounts of the corresponding functional mRNA, suggesting a pretranslational site of action for both glucagon and dexamethasone.