UEKNABLADID 1999; 85 399 meo slembiurtökum: 12-15 ára stúlkum (n=325), 16, 18 og 20 ára stúlkum (... more UEKNABLADID 1999; 85 399 meo slembiurtökum: 12-15 ára stúlkum (n=325), 16, 18 og 20 ára stúlkum (n=247), 25 ára stúlkum (n=86), 34-48 ára konum (n=107) og 70 ára konum (n=308). Kalkhormón var eingöngu maslt í 70 ára konum. Ennfremur voru gerõar ...
Background: Current assays measuring intact PTH may not only measure the active form, PTH(1-84), ... more Background: Current assays measuring intact PTH may not only measure the active form, PTH(1-84), but also some large breakdown products, including PTH(7-84). A new method is believed to measure only PTH(1-84). The purpose of this study was to examine whether increases in intact PTH that accompany age, weight and worsening renal function could be related to breakdown products interfering with traditional assays. Methods: We used data from an ongoing cross-sectional study on bone health in 40-85 years old Icelanders. Over a 12 month period, 1096 subjects were invited for a DEXA scan, blood test, height and weight measurements and each subject answered a questionnaire on health and medication. For the current analysis we excluded those who were taking medications affecting bone and mineral metabolism. PTH was measured using PTH elecsys (Roche) and the new PTH cap (Scantibodies). We used kappa statistic to assess agreement with regard to levels above upper reference values for each assay and ANOVA, Pearson's and Spearman's correlation coefficients for other analysis. Women and men were analyzed separately. Results: Of 746 individuals who came for the study, after exclusion, 247 women and 209 men remained for this analysis. PTH was on the average roughly 40% lower with the new PTH cap assay. The correlation between the assays was 0.787 (P<0.001) for women and 0.69 (P<0.001) for men. Kappa statistic was 0.486 (P<0.001) for women and 0.283 (P<0.001) for men, indicating fair to good agreement. PTH elecsys increased with age (P=0.03 and P=0.01 for women and men, respectively) but not PTH cap (P=0.7 and P=0.09 for women and men, respectively). PTH elecsys was positively associated with cystatin C (P<0.05 for both genders), but the correlation between PTH cap and Cystatin C was not statistically significant. The association with body mass index was similar for the two assays (r=0.16 to 0.24, P<0.05) for both genders. Conclusions: There is a significant difference between these two PTH assays. It is likely that increases in intact PTH observed with age and worsening renal function are related to large breakdown products of PTH whereas the PTH increase seen with higher weight seems to be related to PTH(1-84) itself.
Objective: The aim of this study was to evaluate at which age peak bone mass is reached among Ice... more Objective: The aim of this study was to evaluate at which age peak bone mass is reached among Icelandic women. Previous studies on this subject have been conflicting indicating that this might be reached sometime between the age of 16 and 35 years. We have also analyzed associated nutritional and physical factors which might be of use for preventive measures against osteoporosis. Material and methods: A random sample of 16, 18, 20 and 25 years old women in Reykjavik were invited, altogether 335 women participated. Bone mineral density (BMD) was analyzed by Dual Energy X-ray Absorptiometry (DEXA) in the lumbar spine, hip, forearm and total skeleton. Calcium, protein and vitamin D intake was assessed by a semiquantitative food frequency questionnaire. The level of 25-OH-vitamin D in serum was measured by a radioimmunoassay. Physical activity was assessed by a questionnaire. Multivariate analysis was performed by multiple linear regression. Results: Maximal bone mineral density was reached for total skeleton, hip and forearm at the age of 20 years, BMD for the lumbar spine was 1% higher at the age of 25 than at 20 years but this was not statistically significant. No significant association was found between the calcium intake and BMD except in the subgroup of 18 years old women with calcium intake below 1000 mg/day. 25-OH-vitamin D levels were low (<25 nmol/L) in 15-18.5% of the groups but still no significant relationship was found with the bone mineral density. The strongest correlation was found between total BMD and the lean mass (0.38-0.53, p<0.01) but physical activity was also a significant factor in the age groups 16-20 years. About 25-30% of BMD variability can be attributed to these modifiable factors. Conclusion: Peak bone mass seems to be reached at the age of 20 and measures to increase it should therefore be emphasized before that age. Our results indicate that modifiable factors, especially lean mass and physical activity, are of considerable importance in the attainment of peak bone mass in women.
Objective: The aim of this study was to evaluate the vitamin D intake and serum concentrations of... more Objective: The aim of this study was to evaluate the vitamin D intake and serum concentrations of 25-OH-vitamin D (25-OH-D) in different age groups of Icelandic women. The seasonal variation of 25-OH-D and its relationship with parathyroid hormone (PTH) level was evaluated but some studies have indicated that subclinical vitamin D deficiency may lead to osteoporosis because of secondary elevations of parathyroid hormone levels and subsequent bone mineral release. Material and methods: 25-OH-D was measured (RIA, Incstar) in serum from the following age groups of women; 12-15 years (n=325), 16, 18 and 20 years (n=247), 25 years (n=86), 34-48 years (n=107) and in 70 years old (n=308). PTH (IRMA, Nichols) was measured only in the 70 years old. vitamin D intake was assessed by a standardized food frequency questionnaire. The seasonal variation of 25-OH-D was evaluated in the age group 12-15 years and 70 years old. Results: In the different age groups the 25-OH-D concentration was positively correlated to vitamin D intake (r=0.2-0.54; p<0.05). The mean concentration of 25-OH-D in 12-15 years old was 34.6+/-22 nmol/L compared to 53.9120 nmol/L in the 70 years old, p<0.01. The levels of the other age groups were in between. A marked seasonal variation in 25-OH-D was obser notved in the 12-15 years old with low vitamin D intake whereas only a slight seasonal variation was noted in the 70 years old with a mean vitamin D intake of 15 ug/day. Conclusions: The vitamin D status amongst 70 years old women in Iceland is good because of common intake of codliveroil and vitamin D supplements (83%). The desirable level for 25-OH-D in this age group seems to be around 50 nmol/L and this level is achieved by the intake of 15-20 ug/day (600-800 units) of vitamin D. Vitamin D deficiency is however common amongst 12-15 years old during late winter. Low serum 25-OH-D levels are also common amongst the other age groups studied during late winter. From the results it seems reasonable to recommend that foods like milk should be fortified with vitamin D in Iceland, especially during winter time.
Objective: To study physical activity among Icelandic adults and the relationship with anthropome... more Objective: To study physical activity among Icelandic adults and the relationship with anthropometric factors and grip strength. Material and methods: Randomly selected participants, 30-85 years of age, answered questions regarding exercise and diet. Body composition was measured with DXA, which detects the proportions of different body tissues. Height, weight and grip strength were measured and the body mass index (kg/m(2)) was calculated. The prevalence of regular physical activity was studied for men and women in the age groups of 30-45 years, 50-65 years and 70-85 years and the relationship to body mass index, body composition and grip strength examined. The possible preventive effect of exercise on overweight and obesity was also studied. Results: Of 2310 invited, 1630 subjects (70.6%) participated. Mean participation in regular physical activity was 3-4 times a week but 19% of the women and 24% of the men did no exercise at all. In general, swimming, walking and calisthenics of various types and intensities were the most common forms of exercise and in the age group 30-45 year old 16% of the women and 8% of the men did strength training. 50.4% of women 30-45 years of age and 68.2% of 50-65 year old men were overweight or obese. Mean fat mass was highest in 70-85 year old women (38%) and men (27%). Occupational activity was not related to body mass index, body composition or grip strength. Significant negative relationship was found between frequency of exercise and fat mass. The relationship between grip strength and lean mass or exercise was non-significant. The odds ratio of being overweight or obesity was 0.5 (CI was 0.37-0.77 for women and 0.37-0.94 for men) for those who exercised five or more days per week compared to those who exercised less frequently. Conclusion: One of four Icelandic men and one of five women do not participate in regular physical activity despite of strong scientific indications of various positive health effects of exercise. More than half of adult Icelanders are overweight or obese but the risk is halved among those who exercise at least five days per week, compared to those who exercise less frequently. Sedentary lifestyle is more common amongst Icelanders than in the neighboring countries and realistic goals need to be set to increase the participation in regular physical activity.
Introduction: SHPT is a consequence of decreased concentration of ionized calcium in blood, which... more Introduction: SHPT is a consequence of decreased concentration of ionized calcium in blood, which may have many causes. The purpose of this study was to assess the prevalence and contributing factors of SHPT in an adult Icelandic population and explore the relationship between PTH and other variables which might explain age related increase in PTH. Such knowledge might be helpful in evaluating the results of PTH measurements. METHODS AND STUDY GROUP: The study group was a random sample of men and women in the Reykjavik area, 30-85 years of age. Serum PTH was measured by ECLIA (Roche Diagnostics), serum 25(OH)D by RIA (DiaSorin), and body composition by DXA. SHPT was defined as PTH >65 ng/l and ionized calcium <1.25 mmol/l. Inadequate vitamin D was defined as serum 25(OH)D 25-45 nmol/l and vitamin D deficiency <25 nmol/l, inadequate calcium intake <800 mg/day (from questionnaire) and reduced kidney function as serum cystatin-C >1.55 ng/l. The relationship between PTH and other variables was assessed by Spearman?s correlation coefficient and linear regression. Results: Of 2,310 individuals invited 1,630 attended (70%), 586 men and 1,023 women. Further 21 were excluded because of primary hyperparathyroidism. Of the total group 6.6% did have SHPT, 7.7% of the women and 4.6% of men (p<0.01 by gender). Underlying causes were identified in 90% of cases, most commonly inadequate vitamin D (73%). Other important causes were obesity, inadequate calcium intake, reduced kidney function and furosemide intake. Many individuals did have more than one possible underlying cause. The concentration of PTH was found in a multivariate linear regression to be associated with age, ionized calcium, 25(OH)D, cystatin-C, smoking, and BMI, especially fat mass. Testosterone did have a weak negative relationship with PTH in men. Conclusions: Most cases of SHPT could be explained by known causes and far the commonest was inadequate vitamin D. The prevalence of SHPT in Iceland is probably higher than described elsewhere, possibly due to less sunlight exposure. These results would suggest that a greater intake of vitamin D is needed in Iceland. The relationship of PTH with body composition, especially fat mass, sex hormones and smoking, needs further evaluation.
We found that age-related decline in bone mineral density (BMD) is more pronounced in women than ... more We found that age-related decline in bone mineral density (BMD) is more pronounced in women than in men, that lean mass was the most important determinant of BMD in all age groups in both sexes, and that different factors may be important for bone health of men and women and at different ages. Multiple factors may affect bone mineral density (BMD). Our objective was to identify the correlates of age-related differences in BMD among men and women. We performed a cross-sectional study involving 490 men and 517 women between the age of 29 and 87 years that were free of medication and diseases known to affect bone metabolism. BMD was measured at various sites using dual-energy X-ray absorptiometry, and factors possibly associated with skeletal status were assessed by direct measurements and a detailed questionnaire. BMD was lower with advancing age at all BMD measurement sites, the greatest difference being for the femoral neck where in women BMD was 37.5 % lower in the oldest compared to that in the youngest age group, but the difference was 22.9 % in men. Levels of free estradiol were sharply lower after age of 40 among women; free testosterone declined gradually with age among men but was not independently associated with BMD. Factors including lean mass, physical activity, ionized calcium, C-terminal telopeptide (CTX), serum sodium, free estradiol, and smoking explained a large fraction of difference in BMD in different age groups but to a varying degree in men and women. Lean mass was the strongest independent factor associated with BMD at all sites among men and women. Age-related decline in BMD is more pronounced in women than in men, but determinants of BMD are multiple and interrelated. Our study indicates that different factors may be important for bone health of men and women and at different ages.
... er náõ, en niöurstööur rannsókna hafa veriõ verulega misvísandi í bessu tilliti eõa 16-35 ára... more ... er náõ, en niöurstööur rannsókna hafa veriõ verulega misvísandi í bessu tilliti eõa 16-35 ára (4-6). í bessari rannsókn höfum viõ reynt aõ meta hvenr hámarksbeinmagni íslenskra kvenna sé náõ og hvort fylgni sé milli beinmagns og mataraeõis, sérstaklega kalks og D-vítamíns ...
It is well known that excessive liquorice intake can induce sodium and fluid retention, hypokalae... more It is well known that excessive liquorice intake can induce sodium and fluid retention, hypokalaemia, hypertension and inhibition of the renin-angiotensin system. We tested whether regular moderate liquorice consumption (50 g and 100 g daily) raises blood pressure (BP) in a normotensive population. Ingestion of 100 g of liquorice daily (n = 30) caused a significant rise in systolic blood pressure (SBP) by a mean of 6.5 mm Hg (P < 0.001) and a fall in plasma potassium by 0.24 mmol/l (P < 0.001); the highest rise in SBP observed was 19 mm Hg. In a subgroup of 13 women the consumption of 50 g of liquorice daily also caused a significant rise in SBP of 5.6 mm Hg (P < 0.001) and DBP of 3.4 mm Hg (P = 0.002). A significant change in the cortisol/cortisone ratio in urine was observed during 100 g liquorice consumption indicating inhibition of 11 beta-hydroxysteroid dehydrogenase in kidneys. The results indicate that liquorice-induced hypertension might be more common than has been appreciated and it important for medical doctors to be on the alert for this effect in both the prevention and treatment of hypertension.
Sigurdsson G, Franzson L (University Hospital, Fossvogur, Reykjavik, Iceland). Increased bone min... more Sigurdsson G, Franzson L (University Hospital, Fossvogur, Reykjavik, Iceland). Increased bone mineral density in a population‐based group of 70‐year‐old women on thiazide diuretics, independent of parathyroid hormone levels (Original Article). J Intern Med 2001; 250: 51–56. Background. Several studies have shown greater bone mineral density (BMD) in people receiving thiazide diuretics compared with controls. Most researchers have related this association to the hypocalciuric effect of thiazides with subsequent rise in serum calcium and fall in parathyroid hormone (PTH) levels. Recent experimental evidence suggests, however, a direct effect of thiazides on osteoblast‐like cells. Objective. To test the hypothesis that the association of thiazides and raised BMD is independent of PTH levels in humans. Subjects. A population‐based group of 248 70‐year‐old Icelandic women, 51 receiving thiazide diuretics, 39 receiving other antihypertensive therapy and the rest acting as controls. Main outcome measures. The independent contribution of thiazide usage and PTH to BMD in a multivariate analysis. Results. The mean BMD was 9.6% greater in the lumbar spine (P &lt; 0.01) and 5.4% greater in the whole skeleton (P &lt; 0.01) amongst thiazide users than in controls, reduced to 7.6% (P &lt; 0.02) and 4.5% (P &lt; 0.01), respectively, when corrected for fat mass which was 5.8 kg greater in the thiazide group. In a multivariate analysis, corrected for body weight and body composition, serum calcium and ln‐PTH, thiazides remained a significant independent predictor of BMD in the total skeleton and lumbar spine, but not in the total hip or femoral neck. Thiazides explained about 3% of the variability in whole body and lumbar spine BMD. Conclusions. Thiazides augment or preserve BMD independent of PTH, implying other mechanisms.
Quantitative ultrasound (QUS) can be used as a screening tool for low bone mineral density (BMD),... more Quantitative ultrasound (QUS) can be used as a screening tool for low bone mineral density (BMD), but clinical guidelines have not been set. The aim of this population-based, cross-sectional study was to compare age-related changes in bone mass measured by QUS (Lunar, Achilles Plus) and dual-energy X-ray absorptiometry (DXA) in a random sample of 1630 individuals (1041 females, 589 males) 30-85 yr of age. Individuals with DXA T-scores &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; or =-2.5 at the femoral neck or total hip were identified and receiver operating curves (ROCs) were used to calculate cutoff points for QUS. Sensitivity, specificity, and kappa statistics were calculated. Age-related bone loss was significantly larger with QUS than DXA at all sites in women. For men, the curves were similar for QUS and DXA in the hip. Similar correlations were found between QUS and DXA in different age groups of both sexes (0.36-0.60). For women aged 50-65 yr, a QUS T-score &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;-1.0 was found to be the most applicable for identifying normal BMD. In the 70-85 yr age group, a T-score &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;-2.5 for women and a T-score &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;-0.5 for men seemed reasonable cutoffs for identifying normal BMD (sensitivity: 86-93%; specificity: 28-44%; discordance: 33-73%). Calcaneal QUS cannot be used for the diagnosis of osteoporosis according to WHO criteria, but it can be of use to exclude osteoporosis in 30-40% of our cases.
UEKNABLADID 1999; 85 399 meo slembiurtökum: 12-15 ára stúlkum (n=325), 16, 18 og 20 ára stúlkum (... more UEKNABLADID 1999; 85 399 meo slembiurtökum: 12-15 ára stúlkum (n=325), 16, 18 og 20 ára stúlkum (n=247), 25 ára stúlkum (n=86), 34-48 ára konum (n=107) og 70 ára konum (n=308). Kalkhormón var eingöngu maslt í 70 ára konum. Ennfremur voru gerõar ...
Background: Current assays measuring intact PTH may not only measure the active form, PTH(1-84), ... more Background: Current assays measuring intact PTH may not only measure the active form, PTH(1-84), but also some large breakdown products, including PTH(7-84). A new method is believed to measure only PTH(1-84). The purpose of this study was to examine whether increases in intact PTH that accompany age, weight and worsening renal function could be related to breakdown products interfering with traditional assays. Methods: We used data from an ongoing cross-sectional study on bone health in 40-85 years old Icelanders. Over a 12 month period, 1096 subjects were invited for a DEXA scan, blood test, height and weight measurements and each subject answered a questionnaire on health and medication. For the current analysis we excluded those who were taking medications affecting bone and mineral metabolism. PTH was measured using PTH elecsys (Roche) and the new PTH cap (Scantibodies). We used kappa statistic to assess agreement with regard to levels above upper reference values for each assay and ANOVA, Pearson's and Spearman's correlation coefficients for other analysis. Women and men were analyzed separately. Results: Of 746 individuals who came for the study, after exclusion, 247 women and 209 men remained for this analysis. PTH was on the average roughly 40% lower with the new PTH cap assay. The correlation between the assays was 0.787 (P<0.001) for women and 0.69 (P<0.001) for men. Kappa statistic was 0.486 (P<0.001) for women and 0.283 (P<0.001) for men, indicating fair to good agreement. PTH elecsys increased with age (P=0.03 and P=0.01 for women and men, respectively) but not PTH cap (P=0.7 and P=0.09 for women and men, respectively). PTH elecsys was positively associated with cystatin C (P<0.05 for both genders), but the correlation between PTH cap and Cystatin C was not statistically significant. The association with body mass index was similar for the two assays (r=0.16 to 0.24, P<0.05) for both genders. Conclusions: There is a significant difference between these two PTH assays. It is likely that increases in intact PTH observed with age and worsening renal function are related to large breakdown products of PTH whereas the PTH increase seen with higher weight seems to be related to PTH(1-84) itself.
Objective: The aim of this study was to evaluate at which age peak bone mass is reached among Ice... more Objective: The aim of this study was to evaluate at which age peak bone mass is reached among Icelandic women. Previous studies on this subject have been conflicting indicating that this might be reached sometime between the age of 16 and 35 years. We have also analyzed associated nutritional and physical factors which might be of use for preventive measures against osteoporosis. Material and methods: A random sample of 16, 18, 20 and 25 years old women in Reykjavik were invited, altogether 335 women participated. Bone mineral density (BMD) was analyzed by Dual Energy X-ray Absorptiometry (DEXA) in the lumbar spine, hip, forearm and total skeleton. Calcium, protein and vitamin D intake was assessed by a semiquantitative food frequency questionnaire. The level of 25-OH-vitamin D in serum was measured by a radioimmunoassay. Physical activity was assessed by a questionnaire. Multivariate analysis was performed by multiple linear regression. Results: Maximal bone mineral density was reached for total skeleton, hip and forearm at the age of 20 years, BMD for the lumbar spine was 1% higher at the age of 25 than at 20 years but this was not statistically significant. No significant association was found between the calcium intake and BMD except in the subgroup of 18 years old women with calcium intake below 1000 mg/day. 25-OH-vitamin D levels were low (<25 nmol/L) in 15-18.5% of the groups but still no significant relationship was found with the bone mineral density. The strongest correlation was found between total BMD and the lean mass (0.38-0.53, p<0.01) but physical activity was also a significant factor in the age groups 16-20 years. About 25-30% of BMD variability can be attributed to these modifiable factors. Conclusion: Peak bone mass seems to be reached at the age of 20 and measures to increase it should therefore be emphasized before that age. Our results indicate that modifiable factors, especially lean mass and physical activity, are of considerable importance in the attainment of peak bone mass in women.
Objective: The aim of this study was to evaluate the vitamin D intake and serum concentrations of... more Objective: The aim of this study was to evaluate the vitamin D intake and serum concentrations of 25-OH-vitamin D (25-OH-D) in different age groups of Icelandic women. The seasonal variation of 25-OH-D and its relationship with parathyroid hormone (PTH) level was evaluated but some studies have indicated that subclinical vitamin D deficiency may lead to osteoporosis because of secondary elevations of parathyroid hormone levels and subsequent bone mineral release. Material and methods: 25-OH-D was measured (RIA, Incstar) in serum from the following age groups of women; 12-15 years (n=325), 16, 18 and 20 years (n=247), 25 years (n=86), 34-48 years (n=107) and in 70 years old (n=308). PTH (IRMA, Nichols) was measured only in the 70 years old. vitamin D intake was assessed by a standardized food frequency questionnaire. The seasonal variation of 25-OH-D was evaluated in the age group 12-15 years and 70 years old. Results: In the different age groups the 25-OH-D concentration was positively correlated to vitamin D intake (r=0.2-0.54; p<0.05). The mean concentration of 25-OH-D in 12-15 years old was 34.6+/-22 nmol/L compared to 53.9120 nmol/L in the 70 years old, p<0.01. The levels of the other age groups were in between. A marked seasonal variation in 25-OH-D was obser notved in the 12-15 years old with low vitamin D intake whereas only a slight seasonal variation was noted in the 70 years old with a mean vitamin D intake of 15 ug/day. Conclusions: The vitamin D status amongst 70 years old women in Iceland is good because of common intake of codliveroil and vitamin D supplements (83%). The desirable level for 25-OH-D in this age group seems to be around 50 nmol/L and this level is achieved by the intake of 15-20 ug/day (600-800 units) of vitamin D. Vitamin D deficiency is however common amongst 12-15 years old during late winter. Low serum 25-OH-D levels are also common amongst the other age groups studied during late winter. From the results it seems reasonable to recommend that foods like milk should be fortified with vitamin D in Iceland, especially during winter time.
Objective: To study physical activity among Icelandic adults and the relationship with anthropome... more Objective: To study physical activity among Icelandic adults and the relationship with anthropometric factors and grip strength. Material and methods: Randomly selected participants, 30-85 years of age, answered questions regarding exercise and diet. Body composition was measured with DXA, which detects the proportions of different body tissues. Height, weight and grip strength were measured and the body mass index (kg/m(2)) was calculated. The prevalence of regular physical activity was studied for men and women in the age groups of 30-45 years, 50-65 years and 70-85 years and the relationship to body mass index, body composition and grip strength examined. The possible preventive effect of exercise on overweight and obesity was also studied. Results: Of 2310 invited, 1630 subjects (70.6%) participated. Mean participation in regular physical activity was 3-4 times a week but 19% of the women and 24% of the men did no exercise at all. In general, swimming, walking and calisthenics of various types and intensities were the most common forms of exercise and in the age group 30-45 year old 16% of the women and 8% of the men did strength training. 50.4% of women 30-45 years of age and 68.2% of 50-65 year old men were overweight or obese. Mean fat mass was highest in 70-85 year old women (38%) and men (27%). Occupational activity was not related to body mass index, body composition or grip strength. Significant negative relationship was found between frequency of exercise and fat mass. The relationship between grip strength and lean mass or exercise was non-significant. The odds ratio of being overweight or obesity was 0.5 (CI was 0.37-0.77 for women and 0.37-0.94 for men) for those who exercised five or more days per week compared to those who exercised less frequently. Conclusion: One of four Icelandic men and one of five women do not participate in regular physical activity despite of strong scientific indications of various positive health effects of exercise. More than half of adult Icelanders are overweight or obese but the risk is halved among those who exercise at least five days per week, compared to those who exercise less frequently. Sedentary lifestyle is more common amongst Icelanders than in the neighboring countries and realistic goals need to be set to increase the participation in regular physical activity.
Introduction: SHPT is a consequence of decreased concentration of ionized calcium in blood, which... more Introduction: SHPT is a consequence of decreased concentration of ionized calcium in blood, which may have many causes. The purpose of this study was to assess the prevalence and contributing factors of SHPT in an adult Icelandic population and explore the relationship between PTH and other variables which might explain age related increase in PTH. Such knowledge might be helpful in evaluating the results of PTH measurements. METHODS AND STUDY GROUP: The study group was a random sample of men and women in the Reykjavik area, 30-85 years of age. Serum PTH was measured by ECLIA (Roche Diagnostics), serum 25(OH)D by RIA (DiaSorin), and body composition by DXA. SHPT was defined as PTH >65 ng/l and ionized calcium <1.25 mmol/l. Inadequate vitamin D was defined as serum 25(OH)D 25-45 nmol/l and vitamin D deficiency <25 nmol/l, inadequate calcium intake <800 mg/day (from questionnaire) and reduced kidney function as serum cystatin-C >1.55 ng/l. The relationship between PTH and other variables was assessed by Spearman?s correlation coefficient and linear regression. Results: Of 2,310 individuals invited 1,630 attended (70%), 586 men and 1,023 women. Further 21 were excluded because of primary hyperparathyroidism. Of the total group 6.6% did have SHPT, 7.7% of the women and 4.6% of men (p<0.01 by gender). Underlying causes were identified in 90% of cases, most commonly inadequate vitamin D (73%). Other important causes were obesity, inadequate calcium intake, reduced kidney function and furosemide intake. Many individuals did have more than one possible underlying cause. The concentration of PTH was found in a multivariate linear regression to be associated with age, ionized calcium, 25(OH)D, cystatin-C, smoking, and BMI, especially fat mass. Testosterone did have a weak negative relationship with PTH in men. Conclusions: Most cases of SHPT could be explained by known causes and far the commonest was inadequate vitamin D. The prevalence of SHPT in Iceland is probably higher than described elsewhere, possibly due to less sunlight exposure. These results would suggest that a greater intake of vitamin D is needed in Iceland. The relationship of PTH with body composition, especially fat mass, sex hormones and smoking, needs further evaluation.
We found that age-related decline in bone mineral density (BMD) is more pronounced in women than ... more We found that age-related decline in bone mineral density (BMD) is more pronounced in women than in men, that lean mass was the most important determinant of BMD in all age groups in both sexes, and that different factors may be important for bone health of men and women and at different ages. Multiple factors may affect bone mineral density (BMD). Our objective was to identify the correlates of age-related differences in BMD among men and women. We performed a cross-sectional study involving 490 men and 517 women between the age of 29 and 87 years that were free of medication and diseases known to affect bone metabolism. BMD was measured at various sites using dual-energy X-ray absorptiometry, and factors possibly associated with skeletal status were assessed by direct measurements and a detailed questionnaire. BMD was lower with advancing age at all BMD measurement sites, the greatest difference being for the femoral neck where in women BMD was 37.5 % lower in the oldest compared to that in the youngest age group, but the difference was 22.9 % in men. Levels of free estradiol were sharply lower after age of 40 among women; free testosterone declined gradually with age among men but was not independently associated with BMD. Factors including lean mass, physical activity, ionized calcium, C-terminal telopeptide (CTX), serum sodium, free estradiol, and smoking explained a large fraction of difference in BMD in different age groups but to a varying degree in men and women. Lean mass was the strongest independent factor associated with BMD at all sites among men and women. Age-related decline in BMD is more pronounced in women than in men, but determinants of BMD are multiple and interrelated. Our study indicates that different factors may be important for bone health of men and women and at different ages.
... er náõ, en niöurstööur rannsókna hafa veriõ verulega misvísandi í bessu tilliti eõa 16-35 ára... more ... er náõ, en niöurstööur rannsókna hafa veriõ verulega misvísandi í bessu tilliti eõa 16-35 ára (4-6). í bessari rannsókn höfum viõ reynt aõ meta hvenr hámarksbeinmagni íslenskra kvenna sé náõ og hvort fylgni sé milli beinmagns og mataraeõis, sérstaklega kalks og D-vítamíns ...
It is well known that excessive liquorice intake can induce sodium and fluid retention, hypokalae... more It is well known that excessive liquorice intake can induce sodium and fluid retention, hypokalaemia, hypertension and inhibition of the renin-angiotensin system. We tested whether regular moderate liquorice consumption (50 g and 100 g daily) raises blood pressure (BP) in a normotensive population. Ingestion of 100 g of liquorice daily (n = 30) caused a significant rise in systolic blood pressure (SBP) by a mean of 6.5 mm Hg (P < 0.001) and a fall in plasma potassium by 0.24 mmol/l (P < 0.001); the highest rise in SBP observed was 19 mm Hg. In a subgroup of 13 women the consumption of 50 g of liquorice daily also caused a significant rise in SBP of 5.6 mm Hg (P < 0.001) and DBP of 3.4 mm Hg (P = 0.002). A significant change in the cortisol/cortisone ratio in urine was observed during 100 g liquorice consumption indicating inhibition of 11 beta-hydroxysteroid dehydrogenase in kidneys. The results indicate that liquorice-induced hypertension might be more common than has been appreciated and it important for medical doctors to be on the alert for this effect in both the prevention and treatment of hypertension.
Sigurdsson G, Franzson L (University Hospital, Fossvogur, Reykjavik, Iceland). Increased bone min... more Sigurdsson G, Franzson L (University Hospital, Fossvogur, Reykjavik, Iceland). Increased bone mineral density in a population‐based group of 70‐year‐old women on thiazide diuretics, independent of parathyroid hormone levels (Original Article). J Intern Med 2001; 250: 51–56. Background. Several studies have shown greater bone mineral density (BMD) in people receiving thiazide diuretics compared with controls. Most researchers have related this association to the hypocalciuric effect of thiazides with subsequent rise in serum calcium and fall in parathyroid hormone (PTH) levels. Recent experimental evidence suggests, however, a direct effect of thiazides on osteoblast‐like cells. Objective. To test the hypothesis that the association of thiazides and raised BMD is independent of PTH levels in humans. Subjects. A population‐based group of 248 70‐year‐old Icelandic women, 51 receiving thiazide diuretics, 39 receiving other antihypertensive therapy and the rest acting as controls. Main outcome measures. The independent contribution of thiazide usage and PTH to BMD in a multivariate analysis. Results. The mean BMD was 9.6% greater in the lumbar spine (P &lt; 0.01) and 5.4% greater in the whole skeleton (P &lt; 0.01) amongst thiazide users than in controls, reduced to 7.6% (P &lt; 0.02) and 4.5% (P &lt; 0.01), respectively, when corrected for fat mass which was 5.8 kg greater in the thiazide group. In a multivariate analysis, corrected for body weight and body composition, serum calcium and ln‐PTH, thiazides remained a significant independent predictor of BMD in the total skeleton and lumbar spine, but not in the total hip or femoral neck. Thiazides explained about 3% of the variability in whole body and lumbar spine BMD. Conclusions. Thiazides augment or preserve BMD independent of PTH, implying other mechanisms.
Quantitative ultrasound (QUS) can be used as a screening tool for low bone mineral density (BMD),... more Quantitative ultrasound (QUS) can be used as a screening tool for low bone mineral density (BMD), but clinical guidelines have not been set. The aim of this population-based, cross-sectional study was to compare age-related changes in bone mass measured by QUS (Lunar, Achilles Plus) and dual-energy X-ray absorptiometry (DXA) in a random sample of 1630 individuals (1041 females, 589 males) 30-85 yr of age. Individuals with DXA T-scores &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; or =-2.5 at the femoral neck or total hip were identified and receiver operating curves (ROCs) were used to calculate cutoff points for QUS. Sensitivity, specificity, and kappa statistics were calculated. Age-related bone loss was significantly larger with QUS than DXA at all sites in women. For men, the curves were similar for QUS and DXA in the hip. Similar correlations were found between QUS and DXA in different age groups of both sexes (0.36-0.60). For women aged 50-65 yr, a QUS T-score &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;-1.0 was found to be the most applicable for identifying normal BMD. In the 70-85 yr age group, a T-score &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;-2.5 for women and a T-score &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;-0.5 for men seemed reasonable cutoffs for identifying normal BMD (sensitivity: 86-93%; specificity: 28-44%; discordance: 33-73%). Calcaneal QUS cannot be used for the diagnosis of osteoporosis according to WHO criteria, but it can be of use to exclude osteoporosis in 30-40% of our cases.
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