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Biomedical subjects

L Ovesen

Publications and source records attributed to L Ovesen.

At least 55 records · Page 3Linked to original sources
PubMed2000

Thyroid disorders in mild iodine deficiency.

Comparative epidemiologic studies in areas with low and high iodine intake and controlled studies of iodine supplementation have demonstrated that the major consequence of mild-to-moderate iodine deficiency for the health of the population is an extraordinarily high occurrence of hyperthyroidism in elderly subjects, especially women, with risk of cardiac arrhythmias, osteoporosis, and muscle wasting. The hyperthyroidism is caused by autonomous nodular growth and function of the thyroid gland and it is accompanied by a high frequency of goiter. Pregnant women and small children are not immediately endangered but the consequences of severe iodine deficiency for brain development are grave and a considerable safety margin is advisable. Moreover, a shift toward less malignant types of thyroid cancer and a lower radiation dose to the thyroid in case of nuclear fallout support that mild-to-moderate iodine deficiency should be corrected. However, there is evidence that a high iodine intake may be associated with more autoimmune hypothyroidism, and that Graves' disease may manifest at a younger age and be more difficult to treat. Hence, the iodine intake should be brought to a level at which iodine deficiency disorders are avoided but not higher. Iodine supplementation programs should aim at relatively uniform iodine intake, avoiding deficient or excessive iodine intake in subpopulations. To adopt such a strategy, surveillance programs are needed.

Denmark↗
PubMed2000

Folate intake, lifestyle factors, and homocysteine concentrations in younger and older women.

BACKGROUND: An elevated total homocysteine (tHcy) concentration is considered to be an independent risk factor for cardiovascular diseases and has also been associated with an increased risk of neural tube defects. OBJECTIVE: The objective of this study was to investigate folate intake, folate status, and the association between folate intake, other dietary and lifestyle factors, and tHcy concentrations in young and older women. DESIGN: tHcy concentrations were measured in 290 young women aged 25-30 y and in 288 older women aged 60-65 y. All participants completed questionnaires about factors including lifestyle, health, and use of vitamin supplements. Red blood cell folate was measured in 204 of the participants. A subgroup of 258 participants completed dietary records. RESULTS: Median tHcy was 7.6 micromol/L (range: 6.5-8.9) in the younger women and 9.4 micromol/L (7.7-11.1) in the older women. Folate intake from diet was 283 (224-348) and 268 (210-326) microg/d, respectively, in the 2 age groups. Folic acid intake from supplements (P: < 0.001 for the younger women and P: = 0.026 for the older women) and total folate intake (P: = 0.024 and P: = 0.079) were inversely associated with log tHcy in multiple linear regression analyses. Smoking status, coffee consumption, systolic blood pressure, and body mass index were positively associated and estrogen replacement therapy and tea consumption were inversely associated with log tHcy in some of the models. CONCLUSIONS: According to the criteria used, between 1% and 36% of the women had suboptimal folate intake. Folic acid is a strong predictor of tHcy concentration; however, several dietary and other lifestyle factors seem to be important as well.

Adult↗
PubMed2000

Comparative study of thyroid function and types of thyroid dysfunction in two areas in Denmark with slightly different iodine status.

OBJECTIVE: The pattern of thyroid dysfunction seems to depend on the iodine status of the population. Prevalence of thyroid dysfunction could be a parameter to consider when evaluating iodine deficiency disorders in a population. DESIGN: Comparative cross-sectional investigation in two regions in Denmark with marginally different iodine excretion. METHODS: A random selection of 4649 participants from the Civil Registration System in Denmark in age groups between 18 and 65 years were examined. Thyroid dysfunction was evaluated from blood samples and questionnaires, and compared with results from ultrasonography. RESULTS: Median iodine excretion was 53 microg/l in Aalborg and 68 microg/l in Copenhagen. Previously diagnosed thyroid dysfunction was found with the same prevalence in the regions. Serum TSH was lower in Aalborg than in Copenhagen (P=0. 003) and declined with age in Aalborg, but not in Copenhagen. Not previously diagnosed hyperthyroidism was found with the same overall prevalence in the regions, but in age >40 years hyperthyroidism was more prevalent in Aalborg (1.3 vs 0.5%, P=0.017). Not previously diagnosed hypothyroidism was found more frequently in Aalborg (0.6 vs 0.2%, P=0.03). Hyperthyroidism was more often associated with macronodular thyroid structure at ultrasound in Aalborg and hypothyroidism was more often associated with patchy thyroid structure in Copenhagen. CONCLUSIONS: Significant differences in thyroid dysfunction were found between the regions with a minor difference in iodine excretion. The findings are in agreement with a higher prevalence of thyroid autonomy among the elderly in the most iodine-deficient region.

Adolescent↗
PubMed1999

Iron status in Danes updated 1994. I: prevalence of iron deficiency and iron overload in 1332 men aged 40-70 years. Influence Of blood donation, alcohol intake, and iron supplementation.

Iron status, S-ferritin, and hemoglobin (Hb) were assessed in a population survey in 1994 (DAN-MONICA 10) comprising 1332 Caucasian Danish men equally distributed in age cohorts of 40, 50, 60 and 70 years. Blood donors (n=186) had lower S-ferritin, median 76 microg/l, than nondonors, median 169 microg/l (p<0.0001). S-ferritin in donors was inversely correlated with the number of phlebotomies (r(s)=-0.57, p<0.0001). S-ferritin in nondonors (n=1146) was similar in men 40-60 years of age, median 176 microg/l, and subsequently decreased at 70 years of age to a median of 146 microg/l (p=0.01). In the entire series, the prevalence of small iron stores (S-ferritin 16-32 microg/l) was 2.7%, that of depleted iron stores (S-ferritin <16 microg/l) 0.45%, and that of iron deficiency anemia (S-ferritin <13 microg/l and Hb <129 g/l) 0.15%. Among nondonors, the prevalence of iron overload (S-ferritin >300 microg/l) was 20%. S-ferritin in nondonors correlated with body mass index (r(s)=0.19, p=0.0001) and with alcohol intake (r(s)=0.26, p=0.0001). In the entire series, 28% of the subjects took supplemental iron (median 14 mg ferrous iron daily). Iron supplements had no influence on iron status. Nondonors (n=170) treated with acetylsalicylic acid had lower S-ferritin, median 136 microg/l, than nontreated, median 169 microg/l (p<0.001) and those treated with H(2)-receptor antagonists (n=30) had lower S-ferritin, median 142 microg/l, than nontreated, median 171 microg/l (p<0.04). Compared with the DAN-MONICA 1 iron status survey of Danish men in 1984, the prevalences of iron depletion and iron deficiency anemia are unchanged whereas the prevalence of iron overload has increased significantly. In Denmark, iron fortification of flour was abolished in 1987. This apparently had no negative effect on iron status in men.

Adult↗
PubMed1999

Day-to-day and within-day variation in urinary iodine excretion.

OBJECTIVE: To examine the day-to-day and within-day variation in urinary iodine excretion and the day-to-day variation in iodine intake. DESIGN: Collection of consecutive 24-h urine samples and casual urine samples over 24h. SETTING: The study population consisted of highly motivated subjects from our Institute. SUBJECTS: Study 1: Ten healthy subjects (seven females and three males) aged 30-46 y. Study 2: Twenty-two healthy subjects (9 males and 13 females) aged 30-55 y. METHODS: Study 1: 24-h urine samples were collected for four consecutive days. Study 2: Each urine voided over 24 h was collected into separate containers. In both studies dietary records were kept. MAIN OUTCOME MEASURES: Twenty-four-hour urinary iodine excretion, 24-h urinary iodine excretion estimated as I/Cr*24 h Cr and as a concentration in casual urine samples. RESULTS: Study 1: Both iodine excreted in 24-h urine and iodine intake varied from day-to-day. Iodine excretion correlated with iodine intake (=-0.46, P=0.01). Iodine intake (mean 89 +/- 6.5 microg/d) was not significantly different from iodine excretion (mean 95 +/- 5.3 microg/d). Study 2: Twenty-four hour iodine excretion estimated as I/Cr*24 h Cr from the morning urine sample was significantly lower than actual 24-h iodine excretion, whereas 24-h iodine excretion estimated as I/Cr*24 h Cr from the first sample after the morning sample and the last sample before the subjects went to bed was not significantly different from actual 24-h iodine excretion. Twenty-four-hour urine excretion estimated as a concentration was lower than actual 24-h iodine excretion in casual urine taken at any time of the day. CONCLUSIONS: For determination of iodine status in an individual, more than one 24-h urine sample must be used. The use of the I/Cr ratio in casual urine samples is a usable measure of iodine status if corrected for the age- and sex-adjusted 24-h creatinine excretion. Further, the study suggests that fasting morning urine samples would underestimate iodine status in this population.

Adult↗
PubMed1999

Modification of the nutrition questionnaire for elderly to increase its ability to detect elderly people with inadequate intake of energy, calcium, vitamin C and vitamin D.

OBJECTIVE: To validate the Nutrition Questionnaire for Elderly (NQE) aimed at health care personnel -and develop and validate a modified version of the questionnaire (MNQE) to improve its sensitivity in detecting elderly people with inadequate intake of specific nutrients and energy. DESIGN: The NQE was used to rank the nutrient intake of participants as 'acceptable' (OK-->) or 'at risk' (OBS-->) with respect to energy, calcium, vitamin C and vitamin D--nutrients with a high risk of deficiency, especially among the homebound or institutionalised elderly. The sensitivity, specificity and predictive capacity were calculated by means of a 4 d estimated record (study 1). Based on the results minor adjustments of the NQE was made, and the already obtained information was used to assess the theoretical validity of the MNQE (study 2). Finally the MNQE was validated in a new population (study 3). SETTING AND SUBJECTS: Ninety-five old people ( > 65 y) living in nursing-homes (Bagsvaerd or Havdrup), or at home in the same home-care district (Valby) or in the same preventive home-visit district (Rødovre) were recruited. Excluded were those who declined to participate or who were in a terminal condition (n = 3). RESULTS: The sensitivity of the NQE regarding the intakes of energy, calcium, vitamin C and vitamin D was quite low (respectively 0.46, 0.08, 0.05 and 0.38) (study 1). However minor adjustments of the NQE increased the sensitivity both in theory (energy: 0.64, calcium: 0.95, vitamin C: 1.00 and vitamin D: 0.84) (study 2) and in practice (energy: 1.00, calcium: 0.40, vitamin C: 0.86 and vitamin D: 0.85) (study 3). Modification of the NQE did not reduce the high specificity and predictive capacity of the original version. CONCLUSIONS: Modifications of the NQE resulted in a questionnaire with a high sensitivity, specificity and predictive capacity for detecting inadequate intake of energy, calcium, vitamin C and vitamin D in elderly people.

Aged↗
PubMed1999

Validation of ultrasonography of the thyroid gland for epidemiological purposes.

Ultrasonography of the thyroid is often used in epidemiological surveys, thus thorough characterization of the interobserver variation of the different parameters obtained is important. Various methods have been used for measuring thyroid volume, and different formulas have been used for calculation of thyroid volume from the measured dimensions. In this article, two principles of thyroid volume measurement are described in detail: the wellknown method based on the three axes of each lobe and a new principle based on planimetry in two planes. The interobserver variation of the examination and the measuring procedure in itself were tested on 25 participants in a population study. A comparison of postmortem ultrasonography of the thyroid and results of an autopsy was performed. Good correlation and agreement between observers was found for thyroid volume (r = 0.98) and prevalence of thyroid nodules (kappa = 0.72), whereas echogenecity and echopattern showed little agreement. The correlation of thyroid volume by ultrasonography to autopsy results was satisfactory (r = 0.93), but the volume tended to be slightly underestimated even when using the formula pi/6(= 0.52)*length*width*depth. No major differences were found between the performance of the two principles of volume calculation. We conclude that when the measuring procedure is well defined, results of ultrasonography are comparable between observers for thyroid volume and prevalence of thyroid nodules, but not for echogenecity or echopattern. The formula of length*depth*width*pi/6 is suitable for thyroid volume measurement.

Adolescent↗
PubMed1999

Proper chewing.

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Chewing Gum↗
PubMed1999

The 'Mini Nutritional Assessment' (MNA) and the 'Determine Your Nutritional Health' Checklist (NSI Checklist) as predictors of morbidity and mortality in an elderly Danish population.

The purpose of the present study was to evaluate the capacity of the 'Determine Your Nutritional Health' Checklist (NSI Checklist) and the 'Mini Nutritional Assessment' (MNA) methods to predict nutrition-related health problems. Data were from the Danish part of the 'Survey in Europe of Nutrition in the Elderly, a Concerted Action' (SENECA) baseline survey from 1988, and the follow-up study from 1993. Based on the baseline survey thirty-nine (19.3%) of the subjects were classified at high nutritional risk, 103 (51%) were considered at moderate nutritional risk and sixty (29.7%) were within the 'good' range according to the criteria in the NSI Checklist. With the MNA, 171 subjects were classified according to their nutritional risk into a well-nourished group, comprising 78.4%, and a group who were at risk of undernutrition, comprising 21.6% at baseline. A total of 115 subjects participated in the follow-up study. The mortality rate and the prevalence of various morbidity indicators were compared between the different risk groups. The analysis showed that subjects with a high MNA score (> or = 24) had significantly lower mortality (rate ratio estimate: 0.35; 95% Cl 0.18, 0.66) compared with subjects with a low MNA score (< or = 23.5). In contrast, the NSI Checklist score was not a significant predictor of mortality (rate ratio estimate: 1.45; 95% Cl 0.78, 2.71). The sixteen Danes judged to be at high nutritional risk by the NSI Checklist in 1988, had more acute diseases (P < 0.001) than the rest of the participants, between 1988 and 1993. No significant differences were found in the participation rates, hospitalization rates, physician visits, need of help or weight loss between the groups. The thirteen Danes judged to be at risk of undernutrition in 1988 by the MNA, had a lower participation rate (P < 0.01) and higher occurrence of acute disease (P < 0.05), need of help (P < 0.05), and weight loss (P < 0.001) than the well-nourished group, between 1988 and 1993. No significant differences were found in hospitalization rates and physician visits between the two groups. In conclusion, the results indicate that modified versions of the NSI Checklist and the MNA are capable of identifying a group of 70-75-year-old subjects with increased risk of certain nutrition-related health problems. Further, an MNA score < or = 23.5 predicts mortality in a Danish population.

Aged↗
PubMed1998

At which body mass index and degree of weight loss should hospitalized elderly patients be considered at nutritional risk?

The Subjective Global Assessment, the Nutrition Risk Score and a Danish counterpart are simple screening methods to detect patients at risk of nutrition-related complications. The cut-off points used in the screening are a body mass index (BMI) less than 20 kg/m2 (18. 5 kg/m2 in the Danish version) and weight loss more than 5% during the last 1-6 months - regardless of age. This review of the literature indicates that the optimal range of BMI for elderly people is increasing from 20 to 25 kg/m2 to 24-29 kg/m2. It also suggests that a clinically significant weight loss for the elderly is around 5% annually, less than in younger age groups. And finally, even though intervention studies have shown an overall positive effect of nutritional support of the elderly patients, there seems to be a high percentage of the old, especially those initially malnourished, who will not benefit from the support. The conclusion is that other cut-off points should be used for the elderly (65+ years) patients, i.e. BMI less than 24 kg/m2 or any degree of weight loss. This means that nutritional support will be initiated in time to reduce the nutrition related complications.

Aging↗
PubMed1998

Folate and neural tube defects. Recommendations from a Danish working group.

A working group was established to evaluate the need for an increased folate intake in Danish women to decrease the risk of neural tube defects (NTDs). NTD are birth defects which include anencephaly, encephalocele and spina bifida. In Denmark the incidence is about 1.4 per 1,000 pregnancies. Folate is a B-vitamin found in most food groups. In case-control studies and randomised studies, a protective effect of folic acid supplements on NTDs has been found. The studies show that a periconceptional folic acid supplement of 360 micrograms to 4 mg daily decreases the recurrence rate of NTDs. Likewise, in the few studies which calculate folate intake from the diet, a lower risk of NTD with higher intake of folate from the diet has been found. The folate intake can be increased by the diet, by folic acid supplements or by fortification of food with folic acid. It is concluded that the incidence of NTDs in Denmark will decrease if the folate intake in fertile women increases. All women planning pregnancy should receive dietary counselling. Women who do not eat according to the Nordic Nutrition Recommendations, and women with an increased risk due to diseases are recommended a supplement of 400 micrograms folic acid daily from a multivitamin/folic acid tablet. Women who have had a child with NTD and women who themselves have NTDs are recommended a supplement of 5 mg folic acid daily. Dietary changes and supplements should be initiated when pregnancy is planned.

Adolescent↗
PubMed1998

Say cheese.

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Animals↗
PubMed1997

Para-aminobenzoic acid used as a marker for completeness of 24 hour urine: assessment of control limits for a specific HPLC method.

OBJECTIVE AND DESIGN: The study comprised three protocols. Protocol 1 compared a HPLC method with the commonly employed colorimetric diazocoupling method. Protocol 2 examined, if the last dosage of p-aminobenzoic acid (PABA) could be advanced in the old to allow for a delayed age-dependent urinary excretion of PABA. Protocol 3 established limits for recovery of PABA in 24 h urine applying the HPLC method. SUBJECTS AND SETTING: A total of 151 healthy volunteers participated in the study of which 140 were accepted. In protocol 1: 37 subjects aged 20-78 y were included. All subjects took PABA as recommended (80 mg orally at 08.00, 12.00 and 18.00 h). Protocol 2: compared urinary PABA excretion in two groups of 80 y old subjects who had their last PABA dosage administered at 15.00 h (n = 16) and at 18.00 h (n = 31), respectively. Protocol 3: comprised 56 subjects aged 20-80 y. In the younger age group (20-59 y; n = 34) PABA was taken as recommended, whereas in the older age group (60-80 y; n = 22) the last PABA dosage was advanced three hours. RESULTS: Protocol 1: HPLC gave significantly lower PABA recovery results compared to colorimetry, the difference between methods being 23.9 +/- 8.5 mg/24 h (P < 0.001). Protocol 2: higher PABA recoveries were demonstrated with the advanced dosage schedule compared to the recommended schedule (208 +/- 14 mg/24 h vs 181 +/- 22 mg/24 h; P < 0.001). Protocol 3: PABA recovery with HPLC was 211 +/- 12 mg/24 h, and the lower limit comprising 95% of subjects was 187 mg/24 h. Similar PABA recoveries were demonstrated in the younger subjects and the older subjects (211 +/- 11 mg/24 h vs 211 +/- 13 mg/24 h; NS). CONCLUSION: An advanced dosage schedule for PABA in the aged is recommended. Because of lower recoveries with HPLC, the low limit for recovered PABA in a complete 24 h urine differs from the limit based on colorimetry. This study found a limit of 187 mg/24 h corresponding to the lower 95% confidence limit for a single subject.

4-Aminobenzoic Acid↗
PubMed1997

Regulatory aspects of functional foods.

Functional foods and claims belong together, so that many people would define functional goods as those which are claimed to have health-promoting effects. Within the EU such claims are regulated by the Food Labelling Regulations, which prohibit food labelling or advertising to claim that a particular food has the property of preventing, treating or curing a disease, or any reference to such property. Food Labelling Regulations are obviously interpreted differently within the EU; but whatever the interpretation, allagree that claims must not be misleading, and consequently should be based on sound scientific data.

Denmark↗