Olof Gudny Geirsdottir
University of Iceland
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Featured researches published by Olof Gudny Geirsdottir.
Journals of Gerontology Series A-biological Sciences and Medical Sciences | 2012
Olof Gudny Geirsdottir; A. Arnarson; Kristin Briem; Alfons Ramel; Palmi V. Jonsson; Inga Thorsdottir
BACKGROUND Insulin is a stimulator of skeletal muscle protein anabolism and insulin resistance might therefore negatively affect muscle protein metabolism. We investigated muscle mass and physical function before and after a resistance exercise program in participants with prediabetes or type 2 diabetes mellitus (T2DM) in comparison to healthy controls. METHODS This was a secondary analysis of a randomized controlled intervention designed to investigate resistance training among older adults. Glucose metabolism status was not a selection criteria for the trial, and group designation was done retrospectively. Participants (N = 237, 73.7 ± 5.7 y, 58.2% women) participated in a 12-week resistance exercise program (3 times/week; three sets, six to eight repetitions at 75%-80% of the one-repetition maximum), designed to increase strength and muscle mass of major muscle groups. Body composition, muscular strength, timed up and go test, 6-minute walk for distance, and blood chemical variables were measured at baseline and endpoint. RESULTS Participants completing the study (n = 213) experienced significant changes in muscle strength or muscle function, which did not differ significantly between healthy (n = 198), prediabetic (n = 20), and T2DM participants (n = 17). Changes in serum glucose during the intervention differed by group: only glucose improved significantly in the prediabetic group, glucose and triacylglycerol improved significantly in the healthy group, whereas no serum parameter improved significantly in the T2DM group. CONCLUSIONS A 12-week resistance exercise program improves muscle strength and muscle function to a similar extent in healthy, prediabetic, and T2DM elderly people. However, according to our data, T2DM participants do not experience favorable changes in fasting glucose or HbA(1C).
Journal of Nutrition Health & Aging | 2012
Olof Gudny Geirsdottir; A. Arnarson; Kristin Briem; Alfons Ramel; K. Tomasson; Palmi V. Jonsson; Inga Thorsdottir
BackgroundLittle is known about the effects of resistance training on health related quality of life (HRQL) in the elderly.AimThe main purpose of the study was to investigate the effects of resistance training on strength, body composition, functional capacity and HRQL in independent living elderly people. We hypothesised that resistance training would improve lean mass, muscle strength, physical function and HRQL.MethodsSubjects (N = 237, 73.7±5.7yrs, 58.2% female) participated in a 12-week resistance exercise program (3 times/week; 3 sets, 6–8 repetitions at 75–80% of the 1-repetition maximum) designed to increase strength and muscle mass of major muscle groups. Body composition, quadriceps- and grip strength, timed up and go test (TUG), six minute walk for distance (6MW) and HRQL were measured at baseline and endpoint.ResultsTwo hundred-and-four participants completed the study. Although the increase in lean mass was small (+0.8 kg, P<0.01), quadriceps strength (+53.5N), grip strength (+3.0lb), TUG (-0.6sec), 6MW (+33.6m) and HRQL (+1.2 t-score) improved significantly (all P<0.01). Changes in 6MW predicted improvement in HRQL after 12 weeks.ConclusionsOur study shows that a 12-week resistance exercise program significantly improves lean mass, muscle strength, physical function and HRQL in elderly individuals, and that improvements in physical function predict improvements in HRQL. Our study indicates that resistance training should be promoted for the elderly as it has the potential to improve physical performance, thereby prolonging healthy, independent aging.
Food & Nutrition Research | 2008
Olof Gudny Geirsdottir; Inga Thorsdottir
Objective To evaluate a short screening sheet (SSM) for malnutrition and to investigate the nutritional status of patients receiving chemotherapy for cancer of the lungs, colon or breast at an outpatient clinic. Design Full nutritional assessment was conducted to define malnutrition and validate the SSM. Additionally, weight change from earlier healthy weight was evaluated, and calculations for intake of energy-giving nutrients (three-day-weighed food records) and protein balance were performed. After the evaluation study, the SSM was tested in clinical routine and data collected about patients’ need for nutritional counseling. Subjects Patients at the outpatient clinic of the Department of Oncology at Landspitali-University Hospital (n=30 with lung-, colon- or breast cancer in the study population, n=93 with all cancer type in clinical routine screening). Results Malnutrition was defined by full nutritional assessment in 20% of the participating patients and SSM had high sensitivity and specificity. Declining nutritional status of the patients was seen as a negative nitrogen balance and unintentional weight loss from healthy weight, but not as total energy intake, recent weight loss or underweight. The test of SSM in clinical routine showed that 40% were malnourished. According to the patients, 80% needed nutritional counseling but only 17% had such counseling. Conclusion Screening (SSM) for malnutrition in cancer patients is a valid simple approach to define cancer patients for nutritional care. More patients regard themselves in need for nutritional counseling than the number of patients really achieving any.
Nutrition Research | 2013
Olof Gudny Geirsdottir; A. Arnarson; Alfons Ramel; Palmi V. Jonsson; Inga Thorsdottir
Lean body mass (LBM) is important to maintain physical function during aging. We hypothesized that dietary protein intake and leisure-time physical activity are associated with LBM in community-dwelling older adults. To test the hypothesis, participants (n = 237; age, 65-92 years) did 3-day weighed food records and reported physical activity. Body composition was assessed using dual-energy x-ray absorptiometry. Protein intake was 0.98 ± 0.28 and 0.95 ± 0.29 g/kg body weight in male and female participants, respectively. Protein intake (in grams per kilogram of body weight) was associated with LBM (in kilograms); that is, the differences in LBM were 2.3 kg (P < .05) and 2.0 kg (P = .054) between the fourth vs the first and the fourth vs the second quartiles of protein intake, respectively. Only a minor part of this association was explained by increased energy intake, which follows an increased protein intake. Our study shows that dietary protein intake was positively associated with LBM in older adults with a mean protein intake higher than the current recommended daily allowance of 0.8 g/kg per day. Leisure-time physical activity, predominantly consisting of endurance type exercises, was not related to LBM in this group.
European Journal of Clinical Nutrition | 2011
Alfons Ramel; Olof Gudny Geirsdottir; A. Arnarson; Inga Thorsdottir
Background/Objectives:The aims were (1) to compare fat free mass (FFM) estimates from regional hand-held bioelectrical impedance analysis (HHBIA) with conventional BIA (CBIA) and dual energy X-ray absorptiometry (DXA) and (2) to develop a population specific equation for FFM prediction in Icelandic elderly.Subjects/Methods:DXA, CBIA and HHBIA data were available for 98 free-living Icelandic elderly (age=73.0±5.6 years, body mass index=28.8±5.2 kg/m2). Participants were randomized into a development block (n=50) and validation block (n=48). A population specific equation for FFM prediction was calculated using CBIA-derived resistance and anthropometric data from the development block and then compared with other BIA equations (Deurenberg, Segal, company-specific equations) and DXA estimates using the validation block.Results:The correlations between BIA methods and DXA were very high, that is, >0.9; however, mean differences compared with DXA were quite variable, ranging from −5.0 (Deurenberg) to +2.5 (Segal, HHBIA) and +3.3 kg (CBIA). Mean difference of the population-specific equation was below 0.1 kg. The standard deviations of the differences ranged from 2.6 to 3.3 kg. The limits of agreement of the BIA methods were similar and between 9.9 and 12.9 kg.Conclusions:In Icelandic elderly, HHBIA and CBIA produce similar FFM estimates when using company-specific prediction equations. CBIA provides the additional possibility to use a population-specific prediction equation, which yields best results. However, limits of agreement were wide and similar of all employed BIA methods, which indicates principal limitations of BIA analysis in the determination of FFM.
Scandinavian Journal of Public Health | 2015
Olof Gudny Geirsdottir; A. Arnarson; Alfons Ramel; Kristin Briem; Palmi V. Jonsson; Igna Thorsdottir
Aims: Benefits of resistance exercise in elderly people are well documented; however, sustaining these benefits can be difficult and adherence is often poor. Muscular strength and physical function usually decline after a supervised resistance exercise program (REP). We investigated these changes in older adults during an observational follow-up and whether leisure time physical activity (LTPA) or unsupervised resistance exercise (RE) limit these changes. Methods: Subjects (N=236, 73.7±5.7 years, 58.2% female) had participated in a supervised 12-week REP. Quadriceps strength and timed-up-and-go performance (TUG) at follow-up were compared to values before and after REP. Multivariate statistics were used to predict changes in strength or function. Results: Two hundred and eleven (90.3%) participants completed REP and 149 (63.1%) completed follow-up (11.4±2.9 months). Quadriceps strength at follow-up decreased significantly compared to after REP (–27N), but was higher than before REP (+30N). TUG did not decrease during follow-up and was better than before REP (–0.9 seconds). LTPA (+38.0N, p<0.001) and RE (+31.6N, p=0.006) predicted strength at follow-up, although they did not completely prevent loss of strength during follow-up. Conclusions: Quadriceps strength declines after a 12-week resistance exercise program in older adults. Neither LTPA nor RE completely prevents loss of quadriceps strength during follow-up, although they limited the loss. TUG did not change during follow-up and was better at follow-up than before the start of the resistance exercise program.
Nutrition | 2013
Alfons Ramel; A. Arnarson; Olof Gudny Geirsdottir; Palmi V. Jonsson; Inga Thorsdottir
OBJECTIVE Increased protein intake and resistance exercise can be beneficial for maintenance of lean body mass (LBM) in older adults. However, these factors could also negatively affect renal function. We investigated changes in renal function after a 12-wk resistance exercise program combined with protein supplementation in community dwelling older adults. METHODS Patients (N = 237, 73.7 ± 5.7 y, 58.2% female) participated in a 12-wk resistance exercise program (3 times/wk) designed to increase strength and muscle mass of major muscle groups. Participants were randomly assigned to one of three dietary supplements consumed directly after training: whey protein drink (20 g whey protein, 20 g carbohydrates), milk protein drink (20 g milk protein, 20 g carbohydrates), or carbohydrate drink (40 g carbohydrates). Renal function was estimated as glomerular filtration rate (GFR, Cockcroft-Gault formula), and dietary intake was measured as 3-d-weighed food record at baseline and endpoint. RESULTS During the intervention, energy intake did not increase. Carbohydrate intake increased in the carbohydrate group and protein intake increased in the milk group, both approximately in accordance with the supplementation. In the whey group, protein intake did not increase, but carbohydrate intake did. GFR increased after the intervention (+4.4 mL/min/1.73 m2; P < 0.001), and the changes were similar in men and women or in the age quartiles. Changes in GFR at endpoint were not associated with LBM, dietary supplements, or total protein intake. CONCLUSIONS A 12-wk resistance exercise program combined with protein supplementation in community dwelling older adults does not negatively affect GFR. The supplementation had only minor effects on total dietary intake.
Journal of Nutritional Disorders & Therapy | 2018
Olof Gudny Geirsdottir; Milan Chang; Palmi V. Jonsson; Inga Thorsdottir; Alfons Ramel
Body mass index (BMI) does not necessarily predict cardiovascular disease in old populations which has been called obesity paradox. The aims of the present study were to investigate 1) the associations between BMI and body fat in old adults, and 2) whether more sophisticated measures of body fat are stronger associated with cardiovascular risk than BMI. In the current cross-sectional analysis, the participants‘(N=232, 65-92 years) body fatness was estimated using BMI, waist-circumference, DXA (fat mass, visceral fat mass) and cardiovascular risk factors (blood lipids, glucose metabolism, blood pressure) were assessed. BMI correlated highly with fat mass measured by DXA independently from age tertiles and in both genders. In general, body fatness was positively related to several cardiovascular risk factors and this was persistently observed for all the different measures of body fatness. However, fat measures were not associated with total cholesterol or LDL. Sensitivity analysis indicated that BMI ≥ 25 identifies 70-100% of participants with the above mentioned cardiovascular risk factors outside normal range. We conclude in BMI is highly correlated with body fatness in old Icelandic adults. DXA measurement of body fatness is not better in estimating cardiovascular risk in old adults compared to simple BMI.
British Journal of Nutrition | 2018
Áróra Rós Ingadóttir; Anne Marie Beck; Christine Baldwin; Elizabeth Weekes; Olof Gudny Geirsdottir; Alfons Ramel; Thorarinn Gislason; Ingibjorg Gunnarsdottir
Low energy and protein intakes have been associated with an increased risk of malnutrition in outpatients with chronic obstructive pulmonary disease (COPD). We aimed to assess the energy and protein intakes of hospitalised COPD patients according to nutritional risk status and requirements, and the relative contribution from meals, snacks, drinks and oral nutritional supplements (ONS), and to examine whether either energy or protein intake predicts outcomes. Subjects were COPD patients (n 99) admitted to Landspitali University Hospital in 1 year (March 2015-March 2016). Patients were screened for nutritional risk using a validated screening tool, and energy and protein intake for 3 d, 1-5 d after admission to the hospital, was estimated using a validated plate diagram sheet. The percentage of patients reaching energy and protein intake ≥75 % of requirements was on average 59 and 37 %, respectively. Malnourished patients consumed less at mealtimes and more from ONS than lower-risk patients, resulting in no difference in total energy and protein intakes between groups. No clear associations between energy or protein intake and outcomes were found, although the association between energy intake, as percentage of requirement, and mortality at 12 months of follow-up was of borderline significance (OR 0·12; 95 % CI 0·01, 1·15; P=0·066). Energy and protein intakes during hospitalisation in the study population failed to meet requirements. Further studies are needed on how to increase energy and protein intakes during hospitalisation and after discharge and to assess whether higher intake in relation to requirement of hospitalised COPD patients results in better outcomes.
Aging Clinical and Experimental Research | 2014
A. Arnarson; Alfons Ramel; Olof Gudny Geirsdottir; Palmi V. Jonsson; Inga Thorsdottir