The Aging Male
ISSN: 1368-5538 (Print) 1473-0790 (Online) Journal homepage: http://www.tandfonline.com/loi/itam20
Body mass index and functional status in community dwelling older Turkish males Gulistan Bahat, Sevilay Muratlı, Birkan İlhan, Asli Tufan, Fatih Tufan, Yucel Aydin, Nilgun Erten & Mehmet Akif Karan To cite this article: Gulistan Bahat, Sevilay Muratlı, Birkan İlhan, Asli Tufan, Fatih Tufan, Yucel Aydin, Nilgun Erten & Mehmet Akif Karan (2015): Body mass index and functional status in community dwelling older Turkish males, The Aging Male, DOI: 10.3109/13685538.2015.1061493 To link to this article: http://dx.doi.org/10.3109/13685538.2015.1061493
Published online: 01 Jul 2015.
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Date: 19 October 2015, At: 18:14
http://informahealthcare.com/tam ISSN: 1368-5538 (print), 1473-0790 (electronic) Aging Male, Early Online: 1–5 ! 2015 Informa UK Ltd. DOI: 10.3109/13685538.2015.1061493
ORIGINAL ARTICLE
Body mass index and functional status in community dwelling older Turkish males _ Gulistan Bahat, Sevilay Muratlı, Birkan Ilhan, Asli Tufan, Fatih Tufan, Yucel Aydin, Nilgun Erten, and Mehmet Akif Karan
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Department of Internal Medicine, Division of Geriatrics, Istanbul Medical School, Istanbul University, Istanbul, Turkey
Abstract
Keywords
Disability is utmost important on an aging population’s health. Obesity is associated with increased risk for disability. On-the-other-hand, higher-BMI is reported as associated with better functionality in older people in some reports defined as ‘‘obesity paradox’’. There is some evidence on differential relationship between body weight status and functionality by living setting gender, and different populations. We studied the relation between body mass index and functionality in Turkish community dwelling older males accounting for the most confounding factors: age, multimorbidity, polypharmacy and nutritional status. This is a crosssectional study in a geriatric outpatient clinic of a university hospital. Functionality was assessed with evaluation of activities of daily living (ADL) and instrumental activities of daily living (IADL) scales. Nutrition was assessed by mini-nutritional assessment test. Two hundred seventy-four subjects comprised our study cohort. Mean age was 74.4 ± 7.1 years, BMI was 25.8 ± 4.4 kg/m2. Linear regression analysis revealed significant and independent association of lower BMI with higher ADL and IADL scores (B ¼ 0.047 and B ¼ 0.128, respectively) (p50.05) and better nutritional status (B ¼ 1.94 and B ¼ 3.05, respectively) (p50.001) but not with the total number of medications. Higher IADL score was associated with younger age and lower total number of diseases (B ¼ 0.121, B ¼ 0.595, respectively) (p50.05) while ADL was not. We suggest that lower BMI is associated with better functional status in Turkish community-dwelling male older people. Our study recommends longitudinal studies with higher participants from different populations, genders and living settings are needed to comment more.
Body mass index, functionality, male, nutrition, older people
Introduction The effects of disability on an aging population’s health and welfare are utmost important. Apart from quality of life measures, disability is related with mortality in the older person [1–3]. Hence, the factors related to functionality deserve much attention in geriatric medicine. The functional status of an older person is related to many factors, namely, chronological age, chronic diseases, medications, nutritional status and body mass index. Obesity is associated with a variety of poor health outcomes including an increased risk for cardiovascular disease, diabetes, disability and mortality. Very recently, higher obesity rates and increased chronic disease prevalence are reported to increase disability in US elderly [4]. In addition to associated chronic illnesses, it may directly influence physical functions through its detrimental Address for correspondence: Gulistan Bahat, Department of Internal Medicine, Istanbul University, Istanbul Medical School, Capa, Istanbul, Turkey. Tel: + 90 212 414 20 00 33204. Fax: + 90 212 532 42 08. E-mail: [email protected]
History Received 7 May 2015 Revised 6 June 2015 Accepted 9 June 2015 Published online 1 July 2015
impact on lower limb muscular strength and power, plantar foot pressure, inflammatory milieu, sarcopenia and knee osteoarthritis. Increasing evidence suggests people with obesity are at higher risk for functional limitations, especially those related to mobility [5,6]. On the other hand, low BMI usually indicates a state of undernutrition that may affect functional status adversely and high BMI indicates good nutrition and may affect functional status favorably. In this sense, higher BMI is reported as associated with better functional outcomes in older people in some reports [7,8], a situation defined as ‘‘obesity paradox’’. There is some evidence on the differential relationship between body weight status and functional limitations by living setting, i.e. among community-dwelling older people and nursing home residents [7,8], by gender [9–12], and by different ethnic groups [13] but relevant studies still remain scarce [14]. Here, we aimed to study the relation between body mass index and functionality in Turkish community-dwelling older males accounting for the most confounding factors, namely age, multimorbidity, polypharmacy and nutritional status.
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Methods
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Population and setting This study was carried out at the Geriatrics outpatient clinic at Istanbul University Istanbul Medical Faculty Hospital in Turkey. Patients who were evaluated in the Geriatrics outpatient clinics between the years of 2000 and 2010 were assessed cross-sectionally. This outpatient clinic serves all patients 460 years regardless of their illness, co-morbidities and their living settings. However; because the clinic is located far from the nursing-homes, older patients from such institutions are rarely admitted. In this study, patients admitted from nursing homes were excluded. All of the subjects were community-dwelling older people and they were all living in one of the largest metropolitan cities in Turkey, Istanbul. The patients, in whom proper measurements of weight or height could not be performed, i.e. who could not stand still or did not accept the measurement or had not chance to have such measurement due to measuring device unavailability were also excluded (n ¼ 75). Otherwise, all the male community-dwelling outpatients were included in the study (n ¼ 274). Measurements With the patients wearing light indoor clothing without shoes, their height and weight were measured in a standing position. BMIs were calculated from weight (kg) divided by the square of height (m). Functional status was assessed using scales for evaluation of activities of daily living and instrumental activities of daily living [15]. The evaluated activities of daily living (ADL) were eating, transfer to and out of the bed, continence, dressing, and bathing. Instrumental activities of daily living (IADL) were cooking, cleaning, phoning, shopping, coping with transport, finances and use of medication. In these functional status assessment protocols, subjects were given 2 points if they were totally independent, 1 point if they were partially dependent and 0 point if they were totally dependent, in performing evaluated tasks individually. So, the total points were 10 and 14 points for a completely independent patient in ADL and IADL, respectively. Accordingly, patients were scored as having 0 points if they were totally dependent in ADL or IADL [16]. Nutritional assessment was performed using the full version of the Mini Nutritional Assessment test [17]. It is a two-step procedure: screening with the MNA-short form followed by the assessment, if needed, by the full MNA. MNA-SF score 12 excludes malnutrition and malnutrition risk, which rendered further assessment unnecessary. MNF-SF score512 indicates full MNA test. MNA-long form (MNA-LF)423.5 means normal nutritional status, 17–23.5 shows malnutrition risk and 517 indicates malnutrition. MNA-SF was completed in 217 subjects while MNA-LF was completed in 225 subjects. Multimorbidity and polypharmacy were represented by the total number of diseases and drugs, respectively. Diseases (i.e. hypertension, diabetes, hyperlipidemia) and drugs were determined after the evaluation of the patient with a comprehensive geriatric assessment (CGA), physical examination and first-line biochemical tests including the fasting blood glucose,
Aging Male, Early Online: 1–5
creatinine, electrolytes, serum lipids, TSH screening, and using the patients’ self-report and current medication lists. In our geriatrics outpatient clinics, significant osteoarthritis cases are not followed but re-directed to the physical therapy and rehabilitation unit. We do not offer treatment or follow-up for significant osteoarthritis cases and thus, generally, do not incorporate this diagnosis in our medical records. Therefore, all internal medicine diseases, depression and neurodegenerative diseases were taken into account while osteoarthritis was not. This study was conducted according to the guidelines laid down in the Declaration of Helsinki. As this study was based on the retrospective analysis of data from our geriatric outpatient clinics’ patients, we did not apply for ethical committee board approval. Statistical analysis All data were entered into a database and were verified by a second independent person. Numerical variables were given as mean ± standard deviation. Chi-square test with Yates correction and Fisher’s exact test were used for 2 2 contingency tables when appropriate for non-numerical data. Correlations between numerical parameters were analyzed with Pearson test for parametric variables and Spearman’s rho correlation test for nonparametric variables. Linear regression analysis was used by enter method for multivariate analysis of numerical parameters. p Values less than 0.05 were accepted as significant. The statistical analysis was carried out with Statistical Package for Social Sciences for Windows ver. 14.0 (SPSS Inc, Chicago, IL).
Results Demographic and nutritional data In total, 274 male subjects comprised our study cohort. The mean age of subjects was 74.4 ± 7.1 years and 47.4% were 75 years. In nutritional assessment, 158 (72.8%) were well nourished, 51 (23.5%) were under malnourishment risk and 8 (3.7%) were malnourished by MNA-LF. The characteristics of the study population are outlined in Table 1. We analyzed the nutritional status in different BMI classes. In BMI518.5 kg/m2 group, more than half of the subjects (66.7%) were well-nourished. None of the subjects with BMI 425 kg/m2 were malnourished. The detailed results are given in Table 2. Associations of BMI with ADL and IADL A regression model was developed to evaluate the association of BMI with functional scores adjusting for the most confounding factors. In this model, ADL or IADL were dependent variables while age, BMI, nutritional status, total number of diseases and medications were independent variables. In this analysis, higher ADL and IADL scores were related with lower BMI (B ¼ 0.047 and B ¼ 0.128, respectively) (p50.05) and better nutritional status (B ¼ 1.94 and B ¼ 3.05, respectively) (p50.001) but not with the total number of medications. Higher IADL score was associated with younger age and lower total number of diseases
BMI and function in male elderly
DOI: 10.3109/13685538.2015.1061493
(B ¼ 0.121, B ¼ 0.595, respectively) (p50.05) while ADL was not. After documentation of association of better functionality with lower BMI but better nutritional status in regression analysis, we carried out a correlation analysis between BMI and functional scores in different nutritional status groups. In this univariate analysis, there was not any association between BMI and functional scores in any nutrition group (p40.05).
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Discussion In this study of community dwelling older males, we found better nutritional status – etermined by MNA – and lower BMI associated with better functional scores. While the association in between functionality and nutritional status was much more significant (p50.001 versus p50.05), the relation between nutritional status –determined by MNA– and functionality is a well-documented finding [18]. Hence, the remarkable finding of our study was the association of lower BMI with better functionality which was independent of age, nutritional status, number of co-morbidities and medications. Lower BMI may be a finding related to worse nutritional status. As the height generally decreases by aging, either due to degenerative changes in the intervertebral disc, vertebral osteoporotic fractures or any other means of kyphosis, the ideal lower cut-off point for the older people is suggested higher than the younger counterparts. Furthermore, in some reports higher BMI is reported associated with better Table 1. Baseline characteristics of the subjects (Mean±SD) (Range) or (number and %) (n ¼ 274). Parameters
Mean±SD (Range)
Age (years) 74.4 ± 7.1 (60–95) Body Mass Index (kg/m2) 25.8 ± 4.4 (12.1–44.4) ADL 9.4 ± 1.6 (0–10) IADL 11 ± 4.2 (0–14) No. of chronic diseases 2.6 ± 1.5 (0–9) No. of drugs 4.5 ± 3.2 (0–19) MNA-Short Form (n ¼ 217) 11.6 ± 2.4 (1–14) MNA Long Form (LF) (n ¼ 225) 21 ± 3.5 (9–26.5) Nutritional status MNA-SF/MNA-LF Malnutrition 17 (7.6%)/8 (3.7) Malnutrition risk 64 (28.4%)/51 (23.5%) Normal nutrition 144 (64%)/158 (72.8%) Data are given as mean±standart deviation (minimummaximum) or number and percentage. ADL: activities of daily living, IADL: instrumental activities of daily living, MNA: mini nutritional assessment test, BMI: body mass index.
Table 2. The nutritional status of study population in different BMI classes. BMI class (kg/m2) 518.5 Nutritional status Normal nutrition (%) Malnutrition risk (%) Malnutrition (%) Total n (%)
18.5–25
25–30
30–35
4 (66.7) 55 (60.4)
68 (81)
25 (83.3)
1 (16.7) 29 (31.9%) 16 (19%) 1 (16.7) 7 (7.7%) 6 (100) 91 (100)
5 (16.7%)
none none 84 (100) 30 (100)
435 6 (100) none none 6 (100)
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functionality in older people [7,8]. In this point of view, association of low BMI with better functional scores is an interesting finding and deserves attention. When we analyze the available few studies on nursing home residents, high BMI constantly emerges as a factor associated with better functionality and, moreover, predicting the improved future functionality and mortality [7,8]. On the other hand, among the studies focusing on the relation between BMI and functionality among community-dwelling older people, some report worse functional outcomes associated with higher BMI [12,14,19–25] while some others with lower BMI [12,14,19–21]. However, the association of worse functionality with higher BMI is a more common finding which is also consistent with the outcome of this study. Why higher BMI is associated with better functionality in nursing home residents but worse functionality in the community dwelling older people is unclear. Apparently, the former represent a more frail population which is probably an important modulating factor. We also analyzed whether nutritional status accompanying the lower and higher BMIs are different in these studies in different settings as nutritional status may be important factor in relation of BMI with functional status. In the current study, in BMI 518.5 kg/m2 group, more than half of the subjects (66.7%) were well-nourished. None of the subjects with BMI 425 kg/m2 were malnourished. On the other hand, in our former Turkish nursing home study, in BMI 518.5 kg/m2 group, 89.5% were under-nourished (either in malnutrition or malnutrition risk). None of the subjects with BMI 425 kg/m2 were malnourished [8]. Furthermore, even in 25–29.9 kg/m2 BMI group, there were 3.3% residents with overt malnutrition and 18.9% residents with malnutrition risk yielding more than 1/5 of the residents having under-nutrition. Hence, relativelyhigh rates of undernutrition were present in BMIs regarded as overweight or obese in the nursing home population. We suggest that the significant difference of nutritional status in BMI groups in between the community-dwelling and nursinghome elderly may be an important factor in the opposite direction of association of BMI with functional status in these different living settings. Gender is another significant factor that may modulate the association between BMI and functionality. [9,10,12,14,25]. Imai et al. reported that, among community dwelling US adults, underweight and severe obesity were consistently associated with higher disability in both genders but overweight and moderate obesity showed associations that vary considerably by age and sex [12]. For both older men and women, disability tended to be lowest among overweight persons. The risk of disability was lower in men for moderate obesity at ages greater than in men which was not valid in women. Although this study was concordant with our findings for their report of association of severe obesity with higher disability, it was discordant for their report of positive relation of overweight and moderate obesity. In this aspect, the effect of ethnicity deserves attention. BMI cut-off values vary between ethnic groups [13]. The WHO Expert Committee, did not recommend the use of universal reference data, but encourages the countries to collect their own data on anthropometric measures coupled with health and functional status evaluation [26]. In this aspect, there is a recent data on
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Turkish community-dwelling older females reported by our group [16]. In that study, similar to male counterparts of the current study, we found significant association of lower BMI with better functional status. These findings suggest that the association of BMI with functional status may vary across different populations. After documentation of association of better functionality with lower BMI but better nutritional status, we carried out a correlation analysis between BMI and functional scores in different nutritional status groups. In this univariate analysis, there was not any association between BMI and functional scores in any nutrition group. In our former Turkish community-dwelling female study, there was correlation in univariate analysis for better functional scores with lower BMI in subjects with normal nutrition but not in subjects with malnutrition risk or malnutrition. This difference may be due to different body composition characteristics between males and females, higher prevalences of vertebral osteoporotic fractures which all may change BMI, functionality and nutritional status. Another reason may be the relative lower number of study participants in the current male study compared with the former female study (n ¼ 274 versus 438). The result of our study revealing association between lower BMI and better functionality is important for public concern. The obesity epidemic is a worldwide phenomenon [27]. Furthermore, there is a marked increase in the proportion of obese adults compared to children [28] and its prevalence in elderly people is being reported higher than the youngers people with almost three quarters of those aged between 65 and 74 years classed as obese or overweight [28]. It is reported likely continue to increase, challenging healthcare delivery and financing systems for older people [29]. Increasing evidence suggests people with obesity are at higher risk for functional limitations, especially those related to mobility [5,30]. Thus, the sweeping obesity epidemic is expected to increase the incidence of functional limitations in older population [31]. Recent studies suggest that the obese population may have been growing healthier since the 1960s, as indicated by a decrease in mortality and cardiovascular risk factors. However, whether these improvements have conferred decreased risk for disability is unknown. The obese population may be living longer with better-controlled risk factors but paradoxically experiencing more disability [32]. Recent cardiovascular improvements have not been accompanied by reduced disability within the obese older population, rather an increase. Over time, declines in obesity-related mortality, along with a younger age at onset of obesity, could lead to an increased burden of disability within the obese older population. Our study has some limitations. First, subjects were not among random sampled community-dwelling older people but outpatients. Secondly, this is a cross-sectional study that does not enable to draw causal effect relationship. Lastly, the number of study participants is not high preventing the general applicability of its results. Especially in BMI518.5 kg/m2 and in BMI435 kg/m2, the number of subjects were limited. Nevertheless, it provides an insight for this hot topic the relation between BMI and functionality in the older-population.
Aging Male, Early Online: 1–5
In conclusion, our study suggests that in communitydwelling male older-people, lower BMI is associated with better functionality. Longitudinal studies with higher participants from different populations, genders and living-settings are needed to comment more on this particular subject.
Declaration of interest The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.
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21. Galanos AN, Pieper CF, Cornoni-Huntley JC, et al. Nutrition and function: is there a relationship between body mass index and the functional capabilities of community-dwelling elderly? J Am Geriatr Soc 1994;42:368–73. 22. Jensen GL, Friedmann JM. Obesity is associated with functional decline in community-dwelling rural older persons. J Am Geriatr Soc 2002;50:918–23. 23. Friedmann JM, Elasy T, Jensen GL. The relationship between body mass index and self-reported functional limitation among older adults: a gender difference. J Am Geriatr Soc 2001;49:398–403. 24. den Ouden ME, Schuurmans MJ, Mueller-Schotte S, et al. Domains contributing to disability in activities of daily living. J Am Med Dir Assoc 2013;14:18–24. 25. Armour BS, Courtney-Long E, Campbell VA, Wethington HR. Estimating disability prevalence among adults by body mass index: 2003–2009 National Health Interview Survey. Prev Chronic Dis 2012;9:E178( quiz E178).
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26. de Onis M, Habicht JP. Anthropometric reference data for international use: recommendations from a World Health Organization Expert Committee. Am J Clin Nutr 1996;64:650–8. 27. Wise J. Obesity rates rise substantially worldwide. BMJ 2014;348: g3582. 28. Gulland A. Obesity among over 65s in UK reflects ‘‘lifetime of gaining weight’’. BMJ 2010;341:c3585. 29. Arterburn DE, Crane PK, Sullivan SD. The coming epidemic of obesity in elderly Americans. J Am Geriatr Soc 2004;52:1907–12. 30. Wearing SC, Hennig EM, Byrne NM, et al. The biomechanics of restricted movement in adult obesity. Obes Rev 2006;7:13–24. 31. Sturm R, Ringel JS, Lakdawalla DN, et al. Obesity and disability. The shape of things to come. RAND Research Brief.; increasing obesity rates and disability trends. Health Aff (Millwood) 2004;23: 199–205. 32. Alley DE, Chang VW. The changing relationship of obesity and disability, 1988–2004. JAMA 2007;298:2020–7.
ISSN: 1368-5538 (Print) 1473-0790 (Online) Journal homepage: http://www.tandfonline.com/loi/itam20
Body mass index and functional status in community dwelling older Turkish males Gulistan Bahat, Sevilay Muratlı, Birkan İlhan, Asli Tufan, Fatih Tufan, Yucel Aydin, Nilgun Erten & Mehmet Akif Karan To cite this article: Gulistan Bahat, Sevilay Muratlı, Birkan İlhan, Asli Tufan, Fatih Tufan, Yucel Aydin, Nilgun Erten & Mehmet Akif Karan (2015): Body mass index and functional status in community dwelling older Turkish males, The Aging Male, DOI: 10.3109/13685538.2015.1061493 To link to this article: http://dx.doi.org/10.3109/13685538.2015.1061493
Published online: 01 Jul 2015.
Submit your article to this journal
Article views: 20
View related articles
View Crossmark data
Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=itam20 Download by: [University of Otago]
Date: 19 October 2015, At: 18:14
http://informahealthcare.com/tam ISSN: 1368-5538 (print), 1473-0790 (electronic) Aging Male, Early Online: 1–5 ! 2015 Informa UK Ltd. DOI: 10.3109/13685538.2015.1061493
ORIGINAL ARTICLE
Body mass index and functional status in community dwelling older Turkish males _ Gulistan Bahat, Sevilay Muratlı, Birkan Ilhan, Asli Tufan, Fatih Tufan, Yucel Aydin, Nilgun Erten, and Mehmet Akif Karan
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Department of Internal Medicine, Division of Geriatrics, Istanbul Medical School, Istanbul University, Istanbul, Turkey
Abstract
Keywords
Disability is utmost important on an aging population’s health. Obesity is associated with increased risk for disability. On-the-other-hand, higher-BMI is reported as associated with better functionality in older people in some reports defined as ‘‘obesity paradox’’. There is some evidence on differential relationship between body weight status and functionality by living setting gender, and different populations. We studied the relation between body mass index and functionality in Turkish community dwelling older males accounting for the most confounding factors: age, multimorbidity, polypharmacy and nutritional status. This is a crosssectional study in a geriatric outpatient clinic of a university hospital. Functionality was assessed with evaluation of activities of daily living (ADL) and instrumental activities of daily living (IADL) scales. Nutrition was assessed by mini-nutritional assessment test. Two hundred seventy-four subjects comprised our study cohort. Mean age was 74.4 ± 7.1 years, BMI was 25.8 ± 4.4 kg/m2. Linear regression analysis revealed significant and independent association of lower BMI with higher ADL and IADL scores (B ¼ 0.047 and B ¼ 0.128, respectively) (p50.05) and better nutritional status (B ¼ 1.94 and B ¼ 3.05, respectively) (p50.001) but not with the total number of medications. Higher IADL score was associated with younger age and lower total number of diseases (B ¼ 0.121, B ¼ 0.595, respectively) (p50.05) while ADL was not. We suggest that lower BMI is associated with better functional status in Turkish community-dwelling male older people. Our study recommends longitudinal studies with higher participants from different populations, genders and living settings are needed to comment more.
Body mass index, functionality, male, nutrition, older people
Introduction The effects of disability on an aging population’s health and welfare are utmost important. Apart from quality of life measures, disability is related with mortality in the older person [1–3]. Hence, the factors related to functionality deserve much attention in geriatric medicine. The functional status of an older person is related to many factors, namely, chronological age, chronic diseases, medications, nutritional status and body mass index. Obesity is associated with a variety of poor health outcomes including an increased risk for cardiovascular disease, diabetes, disability and mortality. Very recently, higher obesity rates and increased chronic disease prevalence are reported to increase disability in US elderly [4]. In addition to associated chronic illnesses, it may directly influence physical functions through its detrimental Address for correspondence: Gulistan Bahat, Department of Internal Medicine, Istanbul University, Istanbul Medical School, Capa, Istanbul, Turkey. Tel: + 90 212 414 20 00 33204. Fax: + 90 212 532 42 08. E-mail: [email protected]
History Received 7 May 2015 Revised 6 June 2015 Accepted 9 June 2015 Published online 1 July 2015
impact on lower limb muscular strength and power, plantar foot pressure, inflammatory milieu, sarcopenia and knee osteoarthritis. Increasing evidence suggests people with obesity are at higher risk for functional limitations, especially those related to mobility [5,6]. On the other hand, low BMI usually indicates a state of undernutrition that may affect functional status adversely and high BMI indicates good nutrition and may affect functional status favorably. In this sense, higher BMI is reported as associated with better functional outcomes in older people in some reports [7,8], a situation defined as ‘‘obesity paradox’’. There is some evidence on the differential relationship between body weight status and functional limitations by living setting, i.e. among community-dwelling older people and nursing home residents [7,8], by gender [9–12], and by different ethnic groups [13] but relevant studies still remain scarce [14]. Here, we aimed to study the relation between body mass index and functionality in Turkish community-dwelling older males accounting for the most confounding factors, namely age, multimorbidity, polypharmacy and nutritional status.
2
G. Bahat et al.
Methods
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Population and setting This study was carried out at the Geriatrics outpatient clinic at Istanbul University Istanbul Medical Faculty Hospital in Turkey. Patients who were evaluated in the Geriatrics outpatient clinics between the years of 2000 and 2010 were assessed cross-sectionally. This outpatient clinic serves all patients 460 years regardless of their illness, co-morbidities and their living settings. However; because the clinic is located far from the nursing-homes, older patients from such institutions are rarely admitted. In this study, patients admitted from nursing homes were excluded. All of the subjects were community-dwelling older people and they were all living in one of the largest metropolitan cities in Turkey, Istanbul. The patients, in whom proper measurements of weight or height could not be performed, i.e. who could not stand still or did not accept the measurement or had not chance to have such measurement due to measuring device unavailability were also excluded (n ¼ 75). Otherwise, all the male community-dwelling outpatients were included in the study (n ¼ 274). Measurements With the patients wearing light indoor clothing without shoes, their height and weight were measured in a standing position. BMIs were calculated from weight (kg) divided by the square of height (m). Functional status was assessed using scales for evaluation of activities of daily living and instrumental activities of daily living [15]. The evaluated activities of daily living (ADL) were eating, transfer to and out of the bed, continence, dressing, and bathing. Instrumental activities of daily living (IADL) were cooking, cleaning, phoning, shopping, coping with transport, finances and use of medication. In these functional status assessment protocols, subjects were given 2 points if they were totally independent, 1 point if they were partially dependent and 0 point if they were totally dependent, in performing evaluated tasks individually. So, the total points were 10 and 14 points for a completely independent patient in ADL and IADL, respectively. Accordingly, patients were scored as having 0 points if they were totally dependent in ADL or IADL [16]. Nutritional assessment was performed using the full version of the Mini Nutritional Assessment test [17]. It is a two-step procedure: screening with the MNA-short form followed by the assessment, if needed, by the full MNA. MNA-SF score 12 excludes malnutrition and malnutrition risk, which rendered further assessment unnecessary. MNF-SF score512 indicates full MNA test. MNA-long form (MNA-LF)423.5 means normal nutritional status, 17–23.5 shows malnutrition risk and 517 indicates malnutrition. MNA-SF was completed in 217 subjects while MNA-LF was completed in 225 subjects. Multimorbidity and polypharmacy were represented by the total number of diseases and drugs, respectively. Diseases (i.e. hypertension, diabetes, hyperlipidemia) and drugs were determined after the evaluation of the patient with a comprehensive geriatric assessment (CGA), physical examination and first-line biochemical tests including the fasting blood glucose,
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creatinine, electrolytes, serum lipids, TSH screening, and using the patients’ self-report and current medication lists. In our geriatrics outpatient clinics, significant osteoarthritis cases are not followed but re-directed to the physical therapy and rehabilitation unit. We do not offer treatment or follow-up for significant osteoarthritis cases and thus, generally, do not incorporate this diagnosis in our medical records. Therefore, all internal medicine diseases, depression and neurodegenerative diseases were taken into account while osteoarthritis was not. This study was conducted according to the guidelines laid down in the Declaration of Helsinki. As this study was based on the retrospective analysis of data from our geriatric outpatient clinics’ patients, we did not apply for ethical committee board approval. Statistical analysis All data were entered into a database and were verified by a second independent person. Numerical variables were given as mean ± standard deviation. Chi-square test with Yates correction and Fisher’s exact test were used for 2 2 contingency tables when appropriate for non-numerical data. Correlations between numerical parameters were analyzed with Pearson test for parametric variables and Spearman’s rho correlation test for nonparametric variables. Linear regression analysis was used by enter method for multivariate analysis of numerical parameters. p Values less than 0.05 were accepted as significant. The statistical analysis was carried out with Statistical Package for Social Sciences for Windows ver. 14.0 (SPSS Inc, Chicago, IL).
Results Demographic and nutritional data In total, 274 male subjects comprised our study cohort. The mean age of subjects was 74.4 ± 7.1 years and 47.4% were 75 years. In nutritional assessment, 158 (72.8%) were well nourished, 51 (23.5%) were under malnourishment risk and 8 (3.7%) were malnourished by MNA-LF. The characteristics of the study population are outlined in Table 1. We analyzed the nutritional status in different BMI classes. In BMI518.5 kg/m2 group, more than half of the subjects (66.7%) were well-nourished. None of the subjects with BMI 425 kg/m2 were malnourished. The detailed results are given in Table 2. Associations of BMI with ADL and IADL A regression model was developed to evaluate the association of BMI with functional scores adjusting for the most confounding factors. In this model, ADL or IADL were dependent variables while age, BMI, nutritional status, total number of diseases and medications were independent variables. In this analysis, higher ADL and IADL scores were related with lower BMI (B ¼ 0.047 and B ¼ 0.128, respectively) (p50.05) and better nutritional status (B ¼ 1.94 and B ¼ 3.05, respectively) (p50.001) but not with the total number of medications. Higher IADL score was associated with younger age and lower total number of diseases
BMI and function in male elderly
DOI: 10.3109/13685538.2015.1061493
(B ¼ 0.121, B ¼ 0.595, respectively) (p50.05) while ADL was not. After documentation of association of better functionality with lower BMI but better nutritional status in regression analysis, we carried out a correlation analysis between BMI and functional scores in different nutritional status groups. In this univariate analysis, there was not any association between BMI and functional scores in any nutrition group (p40.05).
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Discussion In this study of community dwelling older males, we found better nutritional status – etermined by MNA – and lower BMI associated with better functional scores. While the association in between functionality and nutritional status was much more significant (p50.001 versus p50.05), the relation between nutritional status –determined by MNA– and functionality is a well-documented finding [18]. Hence, the remarkable finding of our study was the association of lower BMI with better functionality which was independent of age, nutritional status, number of co-morbidities and medications. Lower BMI may be a finding related to worse nutritional status. As the height generally decreases by aging, either due to degenerative changes in the intervertebral disc, vertebral osteoporotic fractures or any other means of kyphosis, the ideal lower cut-off point for the older people is suggested higher than the younger counterparts. Furthermore, in some reports higher BMI is reported associated with better Table 1. Baseline characteristics of the subjects (Mean±SD) (Range) or (number and %) (n ¼ 274). Parameters
Mean±SD (Range)
Age (years) 74.4 ± 7.1 (60–95) Body Mass Index (kg/m2) 25.8 ± 4.4 (12.1–44.4) ADL 9.4 ± 1.6 (0–10) IADL 11 ± 4.2 (0–14) No. of chronic diseases 2.6 ± 1.5 (0–9) No. of drugs 4.5 ± 3.2 (0–19) MNA-Short Form (n ¼ 217) 11.6 ± 2.4 (1–14) MNA Long Form (LF) (n ¼ 225) 21 ± 3.5 (9–26.5) Nutritional status MNA-SF/MNA-LF Malnutrition 17 (7.6%)/8 (3.7) Malnutrition risk 64 (28.4%)/51 (23.5%) Normal nutrition 144 (64%)/158 (72.8%) Data are given as mean±standart deviation (minimummaximum) or number and percentage. ADL: activities of daily living, IADL: instrumental activities of daily living, MNA: mini nutritional assessment test, BMI: body mass index.
Table 2. The nutritional status of study population in different BMI classes. BMI class (kg/m2) 518.5 Nutritional status Normal nutrition (%) Malnutrition risk (%) Malnutrition (%) Total n (%)
18.5–25
25–30
30–35
4 (66.7) 55 (60.4)
68 (81)
25 (83.3)
1 (16.7) 29 (31.9%) 16 (19%) 1 (16.7) 7 (7.7%) 6 (100) 91 (100)
5 (16.7%)
none none 84 (100) 30 (100)
435 6 (100) none none 6 (100)
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functionality in older people [7,8]. In this point of view, association of low BMI with better functional scores is an interesting finding and deserves attention. When we analyze the available few studies on nursing home residents, high BMI constantly emerges as a factor associated with better functionality and, moreover, predicting the improved future functionality and mortality [7,8]. On the other hand, among the studies focusing on the relation between BMI and functionality among community-dwelling older people, some report worse functional outcomes associated with higher BMI [12,14,19–25] while some others with lower BMI [12,14,19–21]. However, the association of worse functionality with higher BMI is a more common finding which is also consistent with the outcome of this study. Why higher BMI is associated with better functionality in nursing home residents but worse functionality in the community dwelling older people is unclear. Apparently, the former represent a more frail population which is probably an important modulating factor. We also analyzed whether nutritional status accompanying the lower and higher BMIs are different in these studies in different settings as nutritional status may be important factor in relation of BMI with functional status. In the current study, in BMI 518.5 kg/m2 group, more than half of the subjects (66.7%) were well-nourished. None of the subjects with BMI 425 kg/m2 were malnourished. On the other hand, in our former Turkish nursing home study, in BMI 518.5 kg/m2 group, 89.5% were under-nourished (either in malnutrition or malnutrition risk). None of the subjects with BMI 425 kg/m2 were malnourished [8]. Furthermore, even in 25–29.9 kg/m2 BMI group, there were 3.3% residents with overt malnutrition and 18.9% residents with malnutrition risk yielding more than 1/5 of the residents having under-nutrition. Hence, relativelyhigh rates of undernutrition were present in BMIs regarded as overweight or obese in the nursing home population. We suggest that the significant difference of nutritional status in BMI groups in between the community-dwelling and nursinghome elderly may be an important factor in the opposite direction of association of BMI with functional status in these different living settings. Gender is another significant factor that may modulate the association between BMI and functionality. [9,10,12,14,25]. Imai et al. reported that, among community dwelling US adults, underweight and severe obesity were consistently associated with higher disability in both genders but overweight and moderate obesity showed associations that vary considerably by age and sex [12]. For both older men and women, disability tended to be lowest among overweight persons. The risk of disability was lower in men for moderate obesity at ages greater than in men which was not valid in women. Although this study was concordant with our findings for their report of association of severe obesity with higher disability, it was discordant for their report of positive relation of overweight and moderate obesity. In this aspect, the effect of ethnicity deserves attention. BMI cut-off values vary between ethnic groups [13]. The WHO Expert Committee, did not recommend the use of universal reference data, but encourages the countries to collect their own data on anthropometric measures coupled with health and functional status evaluation [26]. In this aspect, there is a recent data on
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G. Bahat et al.
Turkish community-dwelling older females reported by our group [16]. In that study, similar to male counterparts of the current study, we found significant association of lower BMI with better functional status. These findings suggest that the association of BMI with functional status may vary across different populations. After documentation of association of better functionality with lower BMI but better nutritional status, we carried out a correlation analysis between BMI and functional scores in different nutritional status groups. In this univariate analysis, there was not any association between BMI and functional scores in any nutrition group. In our former Turkish community-dwelling female study, there was correlation in univariate analysis for better functional scores with lower BMI in subjects with normal nutrition but not in subjects with malnutrition risk or malnutrition. This difference may be due to different body composition characteristics between males and females, higher prevalences of vertebral osteoporotic fractures which all may change BMI, functionality and nutritional status. Another reason may be the relative lower number of study participants in the current male study compared with the former female study (n ¼ 274 versus 438). The result of our study revealing association between lower BMI and better functionality is important for public concern. The obesity epidemic is a worldwide phenomenon [27]. Furthermore, there is a marked increase in the proportion of obese adults compared to children [28] and its prevalence in elderly people is being reported higher than the youngers people with almost three quarters of those aged between 65 and 74 years classed as obese or overweight [28]. It is reported likely continue to increase, challenging healthcare delivery and financing systems for older people [29]. Increasing evidence suggests people with obesity are at higher risk for functional limitations, especially those related to mobility [5,30]. Thus, the sweeping obesity epidemic is expected to increase the incidence of functional limitations in older population [31]. Recent studies suggest that the obese population may have been growing healthier since the 1960s, as indicated by a decrease in mortality and cardiovascular risk factors. However, whether these improvements have conferred decreased risk for disability is unknown. The obese population may be living longer with better-controlled risk factors but paradoxically experiencing more disability [32]. Recent cardiovascular improvements have not been accompanied by reduced disability within the obese older population, rather an increase. Over time, declines in obesity-related mortality, along with a younger age at onset of obesity, could lead to an increased burden of disability within the obese older population. Our study has some limitations. First, subjects were not among random sampled community-dwelling older people but outpatients. Secondly, this is a cross-sectional study that does not enable to draw causal effect relationship. Lastly, the number of study participants is not high preventing the general applicability of its results. Especially in BMI518.5 kg/m2 and in BMI435 kg/m2, the number of subjects were limited. Nevertheless, it provides an insight for this hot topic the relation between BMI and functionality in the older-population.
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In conclusion, our study suggests that in communitydwelling male older-people, lower BMI is associated with better functionality. Longitudinal studies with higher participants from different populations, genders and living-settings are needed to comment more on this particular subject.
Declaration of interest The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.
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