Life expectancy associated with different ages at diagnosis of type 2 diabetes in high-income countries: 23 million person-years of observation

BACKGROUND

The prevalence of type 2 diabetes is increasing rapidly, particularly among younger age groups. Estimates suggest that people with diabetes die, on average, 6 years earlier than people without diabetes. We aimed to provide reliable estimates of the associations between age at diagnosis of diabetes and all-cause mortality, cause-specific mortality, and reductions in life expectancy.

METHODS

For this observational study, we conducted a combined analysis of individual-participant data from 19 high-income countries using two large-scale data sources: the Emerging Risk Factors Collaboration (96 cohorts, median baseline years 1961-2007, median latest follow-up years 1980-2013) and the UK Biobank (median baseline year 2006, median latest follow-up year 2020). We calculated age-adjusted and sex-adjusted hazard ratios (HRs) for all-cause mortality according to age at diagnosis of diabetes using data from 1 515 718 participants, in whom deaths were recorded during 23·1 million person-years of follow-up. We estimated cumulative survival by applying age-specific HRs to age-specific death rates from 2015 for the USA and the EU.

FINDINGS

For participants with diabetes, we observed a linear dose-response association between earlier age at diagnosis and higher risk of all-cause mortality compared with participants without diabetes. HRs were 2·69 (95% CI 2·43-2·97) when diagnosed at 30-39 years, 2·26 (2·08-2·45) at 40-49 years, 1·84 (1·72-1·97) at 50-59 years, 1·57 (1·47-1·67) at 60-69 years, and 1·39 (1·29-1·51) at 70 years and older. HRs per decade of earlier diagnosis were similar for men and women. Using death rates from the USA, a 50-year-old individual with diabetes died on average 14 years earlier when diagnosed aged 30 years, 10 years earlier when diagnosed aged 40 years, or 6 years earlier when diagnosed aged 50 years than an individual without diabetes. Using EU death rates, the corresponding estimates were 13, 9, or 5 years earlier.

INTERPRETATION

Every decade of earlier diagnosis of diabetes was associated with about 3-4 years of lower life expectancy, highlighting the need to develop and implement interventions that prevent or delay the onset of diabetes and to intensify the treatment of risk factors among young adults diagnosed with diabetes.

FUNDING

British Heart Foundation, Medical Research Council, National Institute for Health and Care Research, and Health Data Research UK.

Predictive Role of Aortic Valve Calcium score on post-procedural outcomes and mortality after Transcatheter aortic valve replacement

Introduction

Extent of aortic valve (AV) calcium increases as degenerative aortic valve stenosis progresses. Initial studies postulated AV calcium (AVC) score to be a predictor of complications such as need for pacemaker implantation, paravalvular regurgitation and mortality after Trans-catheter Aortic valve Replacement (TAVR). However, evidence regarding the impact of AVC score as a predictor of post-procedural complications and mortality has been conflicting.

Objective

This study aimed to determine the prognostic impact of AVC as predictor of post-procedural outcomes and mortality in patients with severe aortic stenosis (AS) who underwent TAVR.

Methods

We retrospectively abstracted the records of 497 patients with severe AS who underwent TAVR between January 2016 and July 2019 at our institution. All patients underwent a non-contrast cardiac CT scan on a Siemens Somatom Definition Flash 128 slice scanner. AVC score using the Agatston method was obtained retrospectively. Patients were divided into two groups: 1) Non-severe AVC score group [women <1200 Agatston unit (AU) and men <2000 AU]; 2) Severe AV Calcium Score group [women >1200 AU and men >2000 AU]. Primary outcome was 1-year mortality.

Results

Among 466 patients included in the analysis, 352 patients were included severe AVC group while 114 patients were in the non-severe AVC group. Patients in the severe AVC group were older (81±8 vs 79±8 years), were predominantly males (79% vs 71%), and had less diabetes mellitus (31% vs 42%, p=0.02). Post-TAVR AV dimensionless index (0.58±0.13 vs 0.58±0.12, p=0.8) and AV mean gradient (9.5±4.9 vs 9.2±5.4 mmHg) were not statistically different between both groups. There was no statistical difference in the need for PPM (12% vs 7%, p=0.16), post-TAVR stroke (1.5% vs 0%), post-TAVR major complications (17.4% vs 10%, p=0.07), 30 day (3.7% vs 4.4%), and 1-year mortality (13.6 vs 11.4, p=0.6) between both groups.

Conclusion

Our study report that the severity of AVC score does not have a prognostic impact on major post-procedural outcomes and mortality after TAVR.

Funding Acknowledgement

Type of funding sources: None.

Sex-based differences of the impact of aortic valve calcium score on mortality and post-procedural outcomes after trans-catheter aortic valve replacement

Introduction

Sex based differences exist in the presentation, outcomes, and management of cardiovascular diseases. Although aortic valve calcium (AVC) score has been postulated to be associated with post-procedural outcomes after transcatheter aortic valve replacement (TAVR), data on the impact of AVC score on procedural outcomes after TAVR based on sex have been scarce.

Objective

The aim of the present study was to elucidate sex related differences in the prognostic impact of AVC score as a predictor of post-procedural outcomes and mortality in patients with severe aortic stenosis (AS) who underwent TAVR.

Methods

We retrospectively abstracted the records of 497 patients with severe AS who underwent TAVR between January 2016 and July 2019 at our institution. All patients underwent a non-contrast cardiac CT scan on a Siemens Somatom Definition Flash 128 slice scanner. AVC score using the Agatston method was calculated retrospectively. Primary outcome was 1-year mortality. Patients were divided into two groups: 1) Non-severe AVC score group [women <1200 Agatston unit (AU) and men <2000 AU]; 2) Severe AVC Score group [women >1200 AU and men >2000 AU]. Cox-regression model was used to predict effect of variables on 1-year mortality in male and female patients.

Results

Among 466 patients included, 268 patients were male and 198 were female (57.5% vs 42.5%). When compared with males, female patients had significantly lower AVC score (p<0.001), aortic valve area (AVA) (p<0.001), obstructive CAD (p<0.001), and history of previous PCI (p<0.004), and CABG (<0.001) but had a significantly higher STS score (6.7±3.2 vs 5.8±3.3 P=0.01). There was no difference between need for permanent pacemaker (PPM) implantation (11% vs 9.6%, p=0.4), major complications (16% vs 15%, p=0.9), stroke (0.8% vs 1.6%, p=0.7), 30-day (3.7% vs 4%, p=0.9), and 1-year mortality (14% vs 12%, p=0.6) between males and females, respectively. Female patients required smaller bio-prosthetic valves compared with males (26±3.2 vs 30±3, p<0.001). Cox regression analysis for female patients showed BMI, hemoglobin level, and AVA independently predicted 1-year mortality, while there was no impact of severe AVC score (>1200 AU) on 1-year mortality in females. Similarly, Cox regression analysis for male patients showed there was no impact of severe AVC score (>2000 AU) on 1-year mortality in males. When males in the severe AVC group were compared with female patients in the severe AVC group, there was no difference in 30 day (4.3% vs 3.3%, p=0.82) and 1-year mortality (14.2% vs 13.3%, p=0.77). Similarly, in the severe AVC group there was no difference between need for PPM implantation (12.8% vs 12.1%, p=0.9), major complications (19.7% vs 15.8%, p=0.4), and stroke (2.2% vs 1%, p=0.6) between males and females, respectively.

Conclusion

There were no sex differences in the impact of AVC score on mortality and post-procedural outcomes after TAVR.

Funding Acknowledgement

Type of funding sources: None.

The effect on subsequent fracture risk of age, sex, and prior fracture site by recency of prior fracture

The risk of a recurrent fragility fracture varies by age and sex, as by site and recency of sentinel fracture.

INTRODUCTION

The recency of prior fractures affects subsequent fracture risk. Variable recency may obscure other factors that affect subsequent fracture risk. The aim of this study was to quantify the effect of a sentinel fracture by site, age, and sex where the recency was held constant.

METHODS

The study used data from the Reykjavik Study fracture register that documented prospectively all fractures at all skeletal sites in a large sample of the population of Iceland. Fracture incidence was compared to that of the general population determined at fixed times after a sentinel fracture (humeral, clinical vertebral, forearm, hip, and minor fractures). Outcome fractures comprised a major osteoporotic fracture and hip fracture.

RESULTS

Sentinel osteoporotic fractures were identified in 9504 men and women. Of these, 3616 individuals sustained a major osteoporotic fracture as the first subsequent fracture, of whom 1799 sustained a hip fracture. Hazard ratios for prior fracture were consistently higher in men than in women and decreased progressively with age. Hazard ratios varied according to the site of sentinel fracture with higher ratios for hip and vertebral fracture than for humerus, forearm, or minor osteoporotic fracture.

CONCLUSION

The risk of a recurrent fragility fracture varies by age, sex, and site of sentinel fracture when recency is held constant.

Characteristics of incidence hip fracture cases in older adults participating in the longitudinal AGES-Reykjavik study

Poor physical function and body composition my partly predict the risk of falls leading to fracture regardless of bone mineral density.

INTRODUCTION

To examine the relationship between body composition, physical function, and other markers of health with hip fractures in older community-dwelling Icelandic adults.

METHODS

A prospective cohort of 4782 older adults from the AGES-Reykjavik study. Baseline recruitment took place between 2002 and 2006, and information on hip fractures occurring through 2012 was extracted from clinical records. Using multivariate regression analyses, baseline measures of bone health, physical function, and body composition were compared between those who later experienced hip fractures and to those who did not. Associations with the risk of fractures were quantified using Cox regression.

RESULTS

Mean age was 76.3 years at baseline. After adjustment for age, regression showed that male hip fracture cases compared with non-cases had (mean (95% confidence interval)) significantly lower thigh muscle cross-sectional area - 5.6 cm² (- 10.2, - 1.1), poorer leg strength - 28 N (- 49, - 7), and decreased physical function as measured by longer timed up and go test 1.1 s (0.5, 1.7). After adjustment for age, female cases had, compared with non-cases, lower body mass index - 1.5 kg/m2 (- 2.1, - 0.9), less lean mass - 1.6 kg (- 2.5, - 0.8), thigh muscle cross-sectional area - 4.4 cm² (- 6.5, - 2.3), and worse leg strength - 16 N (- 25, - 6). These differences largely persisted after further adjustment for bone mineral density (BMD), suggesting that body composition may contribute to the risk of fracture independent of bone health. When examining the association between these same factors and hip fractures using Cox regression, the same conclusions were reached.

CONCLUSIONS

After accounting for age and BMD, older adults who later experienced a hip fracture had poorer baseline measures of physical function and/or body composition, which may at least partly contribute to the risk of falls leading to fracture.

The use of 2-, 5-, and 10-year probabilities to characterize fracture risk after a recent sentinel fracture

The increase in fracture risk associated with a recent fragility fracture is more appropriately captured using a 10-year fracture probability than 2- or 5-year probabilities.

INTRODUCTION

The recency of prior fractures affects subsequent fracture risk. The aim of this study was to quantify the effect of a recent sentinel fracture, by site, on the 2-, 5-, and 10-year probability of fracture.

METHODS

The study used data from the Reykjavik Study fracture register that documented prospectively all fractures at all skeletal sites in a large sample of the population of Iceland. Fracture probabilities were determined after a sentinel fracture (humeral, clinical vertebral, forearm and hip fracture) occurring within the previous 2 years and probabilities for a prior osteoporotic fracture irrespective of recency. The probability ratios were used to adjust fracture probabilities over a 2-, 5-, and 10-year time horizon.

RESULTS

As expected, probabilities decreased with decreasing time horizon. Probability ratios varied according to age and the site of sentinel fracture. Probability ratios to adjust for a prior fracture within the previous 2 years were higher the shorter the time horizon, but the absolute increases in fracture probabilities were much reduced. Thus, fracture probabilities were substantially lower with time horizons less than 10 years.

CONCLUSION

The 10-year probability of fractures is the appropriate metric to capture the impact of the recency of sentinel fractures. The probability ratios provide adjustments to conventional FRAX estimates of fracture probability for recent sentinel fractures, adjustments which can readily inform clinical decision-making.

Correction to: Characteristics of incidence hip fracture cases in older adults participating in the longitudinal AGES-Reykjavik study

The original version of this article, published on 18 august 2020 contained a mistake. An author's name was misspelled.

Adjusting conventional FRAX estimates of fracture probability according to the recency of sentinel fractures

The risk of a recurrent fragility fracture is particularly high immediately following the fracture. This study provides adjustments to FRAX-based fracture probabilities accounting for the site of a recent fracture.

INTRODUCTION

The recency of prior fractures affects subsequent fracture risk. The aim of this study was to quantify the effect of a recent sentinel fracture, by site, on the 10-year probability of fracture determined with FRAX.

METHODS

The study used data from the Reykjavik Study fracture register that documented prospectively all fractures at all skeletal sites in a large sample of the population of Iceland. Fracture probabilities were determined after a sentinel fracture (humeral, clinical vertebral, forearm and hip fracture) from the hazards of death and fracture. Fracture probabilities were computed on the one hand for sentinel fractures occurring within the previous 2 years and on the other hand, probabilities for a prior osteoporotic fracture irrespective of recency. The probability ratios provided adjustments to conventional FRAX estimates of fracture probability for recent sentinel fractures.

RESULTS

Probability ratios to adjust 10-year FRAX probabilities of a major osteoporotic fracture for recent sentinel fractures were age dependent, decreasing with age in both men and women. Probability ratios varied according to the site of sentinel fracture with higher ratios for hip and vertebral fracture than for humerus or forearm fracture. Probability ratios to adjust 10-year FRAX probabilities of a hip fracture for recent sentinel fractures were also age dependent, decreasing with age in both men and women with the exception of forearm fractures.

CONCLUSION

The probability ratios provide adjustments to conventional FRAX estimates of fracture probability for recent sentinel fractures.

Characteristics of recurrent fractures

The present study, drawn from a sample of the Icelandic population, quantified high immediate risk and utility loss of subsequent fracture after a sentinel fracture (at the hip, spine, distal forearm and humerus) that attenuated with time.

INTRODUCTION

The risk of a subsequent osteoporotic fracture is particularly acute immediately after an index fracture and wanes progressively with time. The aim of this study was to quantify the risk and utility consequences of subsequent fracture after a sentinel fracture (at the hip, spine, distal forearm and humerus) with an emphasis on the time course of recurrent fracture.

METHODS

The Reykjavik Study fracture registration, drawn from a sample of the Icelandic population (n = 18,872), recorded all fractures of the participants from their entry into the study until December 31, 2012. Medical records for the participants were manually examined and verified. First sentinel fractures were identified. Subsequent fractures, deaths, 10-year probability of fracture and cumulative disutility using multipliers derived from the International Costs and Utilities Related to Osteoporotic fractures Study (ICUROS) were examined as a function of time after fracture, age and sex.

RESULTS

Over 10 years, subsequent fractures were sustained in 28% of 1498 individuals with a sentinel hip fracture. For other sentinel fractures, the proportion ranged from 35 to 38%. After each sentinel fracture, the risk of subsequent fracture was highest in the immediate post fracture interval and decreased markedly with time. Thus, amongst individuals who sustained a recurrent fracture, 31-45% did so within 1 year of the sentinel fracture. Hazard ratios for fracture recurrence (population relative risks) were accordingly highest immediately after the sentinel fracture (2.6-5.3, depending on the site of fracture) and fell progressively over 10 years (1.5-2.2). Population relative risks also decreased progressively with age. The utility loss during the first 10 years after a sentinel fracture varied by age (less with age) and sex (greater in women). In women at the age of 70 years, the mean utility loss due to fractures in the whole cohort was 0.081 whereas this was 12-fold greater in women with a sentinel hip fracture, and was increased 15-fold for spine fracture, 4-fold for forearm fracture and 8-fold for humeral fracture.

CONCLUSION

High fracture risks and utility loss immediately after fracture suggest that treatment given as soon as possible after fracture would avoid a higher number of new fractures compared with treatment given later. This provides the rationale for very early intervention immediately after a sentinel fracture.

Imminent risk of fracture after fracture

The risk of major osteoporotic fracture (MOF) after a first MOF is increased over the whole duration of follow-up, but the imminent risk is even higher. If the acute increment in risk in the few years following MOF is amenable to therapeutic intervention, then immediate short-term treatments may provide worthwhile clinical dividends in a very cost-effective manner.

INTRODUCTION

A history of fracture is a strong risk factor for future fractures. The aim of the present study was to determine whether the predictive value of a past MOF for future MOF changed with time.

METHODS

The study was based on a population-based cohort of 18,872 men and women born between 1907 and 1935. Fractures were documented over 510,265 person-years. An extension of Poisson regression was used to investigate the relationship between the first MOF and the second. All associations were adjusted for age and time since baseline.

RESULTS

Five thousand thirty-nine individuals sustained one or more MOFs, of whom 1919 experienced a second MOF. The risk of a second MOF after a first increased by 4% for each year of age (95% CI 1.02-1.06) and was 41% higher for women than men (95% CI 1.25-1.59). The risk of a second MOF was highest immediately after the first fracture and thereafter decreased with time though remained higher than the population risk throughout follow-up. For example, 1 year after the first MOF, the risk of a second fracture was 2.7 (2.4-3.0) fold higher than the population risk. After 10 years, this risk ratio was 1.4 (1.2-1.6). The effect was more marked with increasing age.

CONCLUSIONS

The risk of MOF after a first MOF is increased over the whole follow-up, but the imminent risk is even higher. If the acute increment in risk in the few years following MOF is amenable to therapeutic intervention, then immediate short-term treatments may provide worthwhile clinical dividends in a very cost-effective manner, particularly in the elderly.

Association of bone turnover markers with volumetric bone loss, periosteal apposition, and fracture risk in older men and women: the AGES-Reykjavik longitudinal study

Association between serum bone formation and resorption markers and cortical and trabecular bone loss and the concurrent periosteal apposition in a population-based cohort of 1069 older adults was assessed. BTM levels moderately reflect the cellular events at the endosteal and periosteal surfaces but are not associated with fracture risk.

INTRODUCTION

We assessed whether circulating bone formation and resorption markers (BTM) were individual predictors for trabecular and cortical bone loss, periosteal expansion, and fracture risk in older adults aged 66 to 93 years from the AGES-Reykjavik study.

METHODS

The sample for the quantitative computed tomography (QCT)-derived cortical and trabecular BMD and periosteal expansion analysis consisted of 1069 participants (474 men and 595 women) who had complete baseline (2002 to 2006) and follow-up (2007 to 2011) hip QCT scans and serum baseline BTM. During the median follow-up of 11.7 years (range 5.4-12.5), 54 (11.4 %) men and 182 (30.6 %) women sustained at least one fracture of any type.

RESULTS

Increase in BTM levels was associated with faster cortical and trabecular bone loss at the femoral neck and proximal femur in men and women. Higher BTM levels were positively related with periosteal expansion rate at the femoral neck in men. Markers were not associated with fracture risk.

CONCLUSION

This data corroborates the notion from few previous studies that both envelopes are metabolically active and that BTM levels may moderately reflect the cellular events at the endosteal and periosteal surfaces. However, our results do not support the routine use of BTM to assess fracture risk in older men and women. In light of these findings, further studies are justified to examine whether systemic markers of bone turnover might prove useful in monitoring skeletal remodeling events and the effects of current osteoporosis drugs at the periosteum.

Are bone turnover markers associated with volumetric bone density, size, and strength in older men and women? The AGES-Reykjavik study

Association between serum bone formation and resorption markers and bone mineral, structural, and strength variables derived from quantitative computed tomography (QCT) in a population-based cohort of 1745 older adults was assessed. The association was weak for lumbar spine and femoral neck areal and volumetric bone mineral density.

INTRODUCTION

The aim of this study was to examine the relationship between levels of bone turnover markers (BTMs; osteocalcin (OC), C-terminal cross-linking telopeptide of type I collagen (CTX), and procollagen type 1N propeptide (P1NP)) and quantitative computed tomography (QCT)-derived bone density, geometry, and strength indices in the lumbar spine and femoral neck (FN).

METHODS

A total of 1745 older individuals (773 men and 972 women, aged 66-92 years) from the Age, Gene/Environment Susceptibility (AGES)-Reykjavik cohort were studied. QCT was performed in the lumbar spine and hip to estimate volumetric trabecular, cortical, and integral bone mineral density (BMD), areal BMD, bone geometry, and bone strength indices. Association between BTMs and QCT variables were explored using multivariable linear regression.

RESULTS

Major findings showed that all BMD measures, FN cortical index, and compressive strength had a low negative correlation with the BTM levels in both men and women. Correlations between BTMs and bone size parameters were minimal or not significant. No associations were found between BTMs and vertebral cross-sectional area in women. BTMs alone accounted for only a relatively small percentage of the bone parameter variance (1-10 %).

CONCLUSION

Serum CTX, OC, and P1NP were weakly correlated with lumbar spine and FN areal and volumetric BMD and strength measures. Most of the bone size indices were not associated with BTMs; thus, the selected bone remodeling markers do not reflect periosteal bone formation. These results confirmed the limited ability of the most sensitive established BTMs to predict bone structural integrity in older adults.

The incidence of a first major osteoporotic fracture in Iceland and implications for FRAX

SUMMARY

Based on an extensive cohort study over 25 years, the present study supports the assumption that major osteoporotic fractures can be reasonably predicted from hip fracture rates.

INTRODUCTION

The construct for FRAX models depends on algorithms to adjust for double counting of fracture outcomes in some models and in others, to estimate the incidence of a major fracture from hip fracture rates. The aim of the present study was to test the validity of these algorithms in a large prospective cohort.

METHODS

The incidence of hip, clinical spine, distal forearm, and humerus fracture was determined in the prospective and ongoing population-based Reykjavik Study with follow up of 257,001 person-years. The incidence of a first major fracture was compared with the correction factors used in FRAX to adjust the incidence of several fracture outcomes for double counting. In addition, the incidence of a major osteoporotic fracture estimated from the Icelandic hip fracture rates was compared with the Malmo ratios used in FRAX.

RESULTS

The adjustments necessary to account for multiple fracture outcomes were similar to those previously derived from Sweden. Additionally, incidence of a first major osteoporotic fracture was similar to that derived for FRAX models.

CONCLUSION

The findings of the present study support the algorithms used in FRAX to estimate the incidence of a first major fracture and the predictive value of hip fracture for other major fractures.

Milk consumption throughout life and bone mineral content and density in elderly men and women

Association between bone mineral density and bone mineral content in old age and milk consumption in adolescence, midlife, and old age was assessed. The association was strongest for milk consumption in midlife: those drinking milk daily or more often had higher bone mineral density and content in old age than those drinking milk seldom or never.

INTRODUCTION

The role of lifelong milk consumption for bone mineral density (BMD) and bone mineral content (BMC) in old age is not clear. Here we assess the association between hip BMD and BMC in old age and milk consumption in adolescence, midlife, and current old age.

METHODS

Participants of the Age, Gene/Environment Susceptibility-Reykjavik Study, aged 66-96 years (N = 4,797), reported retrospective milk intake during adolescence and midlife as well as in current old age, using a validated food frequency questionnaire. BMC of femoral neck and trochanteric area was measured by volumetric quantitative computed tomography and BMD obtained. Association was assessed using linear regression models. Differences in BMC, bone volume, and BMD in relation to milk intake were portrayed as gender-specific Z-scores.

RESULTS

Men consuming milk ≥ once/day during midlife had 0.21 higher Z-scores for BMD and 0.18 for BMC in femoral neck (95 % confidence interval 0.05-0.39 and 0.01-0.35, respectively) compared with < once/week. Results were comparable for trochanter. For women the results were similar, with slightly lower differences according to midlife milk consumption. For current and adolescent milk consumption, differences in Z-scores were smaller and only reached statistical significance in the case of BMD for current consumption in men, while this association was less pronounced for BMC.

CONCLUSIONS

Our data suggest that regular milk consumption throughout life, from adolescence to old age, is associated with higher BMC and BMD in old age, with no differences seen in bone volume. The strongest associations are seen for midlife milk consumption in both genders.

Epidemiology of fractures in Iceland and secular trends in major osteoporotic fractures 1989-2008

The incidence of the most common fracture types in Iceland is reported based on individual data from the Reykjavik Study 1967-2008. Time trend is reported for the major osteoporotic fractures (MOS) 1989-2008.

INTRODUCTION

This study aims to assess the incidence of all fractures in Iceland, with emphasis on the rate of hip fractures, and compare the incidence with other populations as well as examine the secular changes.

METHODS

Individuals from the prospective population-based cohort Reykjavik Study were examined between 1967 and 2008 (follow-up 26.5 years), which consisted of 9,116 men and 9,756 women born in 1907-1935, with age range 31-81 years. First fracture incidence was estimated using life table methods with age as the timescale.

RESULTS

Fracture rate increased proportionally with age between the sexes for vertebral and proximal humerus but disproportionally for hip and distal forearm fractures. The ratio of first fracture incidence between the sexes varied considerably by site: 2.65 for hip fractures and the highest for distal forearm fractures at 4.83. By the age of 75, 36.7% of women and 21% of men had sustained a fracture, taking into account competing risk of death. The incidence of hip fractures was similar to results previously published from USA, Sweden, Norway, and Scotland. The incidence of MOS fractures in both sexes decreased over the last decade, except hip fractures in men, which remained unchanged, as reflected in the women/men ratio for the hip, which changed from 2.6 to 1.7.

CONCLUSION

This study adds information to scarce knowledge on the relative fracture incidence of different fractures. The incidence of MOS fractures increased in the latter part of the last century in both sexes and declined during the last decade, less dramatically for men. This information is important for planning health resources.

Effect of finite element model loading condition on fracture risk assessment in men and women: the AGES-Reykjavik study

Proximal femoral (hip) strength computed by subject-specific CT scan-based finite element (FE) models has been explored as an improved measure for identifying subjects at risk of hip fracture. However, to our knowledge, no published study has reported the effect of loading condition on the association between incident hip fracture and hip strength. In the present study, we performed a nested age- and sex-matched case-control study in the Age Gene/Environment Susceptibility (AGES) Reykjavik cohort. Baseline (pre-fracture) quantitative CT (QCT) scans of 5500 older male and female subjects were obtained. During 4-7years follow-up, 51 men and 77 women sustained hip fractures. Ninety-seven men and 152 women were randomly selected as controls from a pool of age- and sex-matched subjects. From the QCT data, FE models employing nonlinear material properties computed FE-strength of the left hip of each subject in loading from a fall onto the posterolateral (FPL), posterior (FP) and lateral (FL) aspects of the greater trochanter (patent pending). For comparison, FE strength in stance loading (FStance) and total femur areal bone mineral density (aBMD) were also computed. For all loading conditions, the reductions in strength associated with fracture in men were more than twice those in women (p≤0.01). For fall loading specifically, posterolateral loading in men and posterior loading in women were most strongly associated with incident hip fracture. After adjusting for aBMD, the association between FP and fracture in women fell short of statistical significance (p=0.08), indicating that FE strength provides little advantage over aBMD for identifying female hip fracture subjects. However, in men, after controlling for aBMD, FPL was 424N (11%) less in subjects with fractures than in controls (p=0.003). Thus, in men, FE models of posterolateral loading include information about incident hip fracture beyond that in aBMD.

Lifelong physical activity in maintaining bone strength in older men and women of the Age, Gene/Environment Susceptibility-Reykjavik Study

We examined if lifelong physical activity is important for maintaining bone strength in the elderly. Associations of quantitative computerized tomography-acquired bone measures (vertebral and femoral) and self-reported physical activity in mid-life (mean age, 50 years), in old age (≥65 years), and throughout life (recalled during old age) were investigated in 2,110 men and 2,682 women in the AGES-Reykjavik Study. Results conclude lifelong physical activity with continuation into old age (≥65 years) best maintains better bone health later in life.

INTRODUCTION

Skeletal loading is thought to modulate the loss of bone in later life, and physical activity is a chief means of affecting bone strength by skeletal loading. Despite much discussion regarding lifelong versus early adulthood physical activity for preventing bone loss later in life, inconsistency still exists regarding how to maintain bone mass later in life (≥65 years).

METHODS

We examined if lifelong physical activity is important for maintaining bone strength in the elderly.

RESULTS

The associations of quantitative computerized tomography-acquired vertebral and femoral bone measures and self-reported physical activity in mid-life (mean age, 50 years), in old age (≥65 years), and throughout life (recalled during old age) were investigated in 2,110 men and 2,682 women in the AGES-Reykjavik Study.

CONCLUSION

Our findings conclude that lifelong physical activity with continuation into old age (≥65 years) best maintains better bone health in the elderly.

Pain prevalence in a university hospital in Iceland

Background/aims

Despite multiple efforts to improve practice, pain is prevalent in many hospital settings causing unnecessary complications and suffering. The aim of the study was to explore the epidemiology of pain in a university hospital in Iceland.

Methods

A point prevalence study was conducted in 23 departments in medical and surgical services in a 650 bed university hospital in January 2011. Data was collected from medical charts and with a questionnaire (APS-POQ-R) assessing pain severity and quality of pain management. Participants had to be 18 years or older, hospitalized for at least 24 h, speak Icelandic, alert, and able to participate.

Results

Of the 369 participants the mean (SD) age was 67.9 (17.6) years (range 18–100) and gender proportions were equal. Response rate was 80%. Of patients in pain (scoring ≥1 on a 0–10 scale) the mean (SD) worst pain severity was 5.6 (2.5). Total pain prevalence was 80.4%, but of patients in pain 36.5% had mild (1–4) pain, 22.6% moderate (5–6) and 40.9% had severe (7–10) pain. The mean (SD) proportion of time spent in severe pain was 25.9% (27.0%). Pain was both more prevalent, [χ2(1, N= 367) = 7.05, p = 0.008] and severe [t(365) =−4.16, p = 0.000] in women compared to men. Similarly, pain was more prevalent [χ2(1, N= 368) = 9.71, p = 0.002] and severe [t(216,2) =−3.18, p = 0.002] in surgical services compared to medical. Worst pain severity was weakly negatively associated with age [r(369) =−0.23, p = 0.000]. Worst pain severity was higher in patients receiving pain medications [t(357) =−9.84, p = 0.000] and in patients using non-pharmacological methods to treat their pain [t(311.7) =−5.76, p = 0.000].

Conclusions

Pain was prevalent in the hospital and an unsatisfactory proportion of patients experienced moderate to severe pain. The quality of pain management in the hospital needs to be improved. Further studies are needed to test and evaluate the efficacy and effectiveness of interventions aimed at advancing pain practice in the hospital setting.

Age-related loss of proximal femoral strength in elderly men and women: the Age Gene/Environment Susceptibility Study--Reykjavik

The risk of hip fracture rises rapidly with age, and is particularly high in women. This increase in fracture risk reflects both the age-related change in the risk of falling and decrements in the strength of the proximal femur. To better understand the extent to which proximal femoral density, structure and strength change with age as a function of gender, we have carried out a longitudinal analysis of proximal femoral volumetric quantitative computed tomographic (vQCT) images in men and women, analyzing changes in trabecular and cortical bone properties, and using subject-specific finite element modeling (FEM) to estimate changes in bone strength. In the AGES-Reykjavik Study vQCT scans of the hip were performed at a baseline visit in 2002-2006 and at a second visit 5.05±0.25 years later. From these, 223 subjects (111 men, 112 women, aged 68-87 years) were randomly selected. The subjects were evaluated for longitudinal changes in three bone variables assessed in a region similar to the total femur region quantified by DXA: areal bone mineral density (aBMD), trabecular volumetric bone mineral density (tBMD) and the ratio of cortical to total tissue volume (cvol/ivol). They were also evaluated for changes in bone strength using FEM models of the left proximal femur. Models were analyzed under single-limb stance loading (F(Stance)), which approximates normal physiologic loading of the hip, as well as a load approximating a fall onto the posterolateral aspect of the greater trochanter (F(Fall)). We computed five-year absolute and percentage changes in aBMD, tBMD, cvol/ivol, F(Fall) and F(Stance). The Mann-Whitney Test was employed to compare changes in bone variables between genders and the Wilcoxon Signed Rank Test was used to compare changes in bone strength between loading conditions. Multiple (linear) regression was employed to determine the association of changes in F(Fall) and F(Stance) with baseline age and five-year weight loss. Both men and women showed declines in indices of proximal femoral density and structure (aBMD: men -3.9±6.0%, women -6.1±6.2%; tBMD: men -14.8±20.3%, women -23.9±26.8%; cvol/ivol: men -2.6±4.6%, women -4.7±4.8%, gender difference: p<0.001). Both men and women lost bone strength in each loading condition (F(Stance): men -4.2±9.9%, women -8.3±8.5%; F(Fall): men -7.0±15.7%, women -12.8±13.2%; all changes from baseline p<0.0001). The gender difference in bone strength loss was statistically significant in both loading conditions (p<0.001 for F(Stance) and P<0.01 for F(Fall)) and F(Fall) was lost at a higher rate than F(Stance) in men (p<0.01) and women (p<0.0001). The gender difference in strength loss was statistically significant after adjustment for baseline age and weight loss in both loading conditions (p<0.01). In these multi-linear models, men showed increasing rates of bone loss with increasing age (F(Fall): p=0.002; F(Stance): p=0.03), and women showed increasing bone strength loss with higher degrees of weight loss (F(Stance): p=0.003). The higher loss of F(Fall) compared to F(Stance) supports previous findings in animal and human studies that the sub-volumes of bone stressed under normal physiologic loading are relatively better protected in aging. The gender difference in hip bone strength loss is consistent with the higher incidence of hip fracture among elderly women.

Early changes in biochemical markers of bone turnover and their relationship with bone mineral density changes after 24 months of treatment with teriparatide

We report the changes in biochemical markers of bone formation during the first 6 months of teriparatide therapy in postmenopausal women with osteoporosis according to previous antiresorptive treatment. Prior therapy does not adversely affect the response to teriparatide treatment. Similar bone markers levels are reached after 6 months of treatment.

INTRODUCTION

The response of biochemical markers of bone turnover with teriparatide therapy in subjects who have previously received osteoporosis drugs is not fully elucidated. We examined biochemical markers of bone formation in women with osteoporosis treated with teriparatide and determined: (1) whether the response is associated with prior osteoporosis therapy, (2) which marker shows the best performance for detecting a response to therapy, and (3) the correlations between early changes in bone markers and subsequent bone mineral density (BMD) changes after 24 months of teriparatide.

METHODS

We conducted a prospective, open-label, 24-month study at 95 centers in 10 countries in 758 postmenopausal women with established osteoporosis (n = 181 treatment-naïve) who had at least one post-baseline bone marker determination. Teriparatide (20 μg/day) was administered for up to 24 months. We measured procollagen type I N-terminal propeptide (PINP), bone-specific alkaline phosphatase (b-ALP), and total alkaline phosphatase (t-ALP) at baseline, 1 and 6 months, and change in BMD at the lumbar spine, total hip and femoral neck from baseline to 24 months.

RESULTS

Significant increases in formation markers occurred after 1 month of teriparatide regardless of prior osteoporosis therapy. The absolute increase at 1 month was lower in previously treated versus treatment-naïve patients, but after 6 months all groups reached similar levels. PINP showed the best signal-to-noise ratio. Baseline PINP correlated positively and significantly with BMD response at 24 months.

CONCLUSIONS

This study suggests that the long-term responsiveness of bone formation markers to teriparatide is not affected in subjects previously treated with antiresorptive drugs.

Male-female differences in the association between incident hip fracture and proximal femoral strength: a finite element analysis study

Hip fracture risk is usually evaluated using dual energy X-ray absorptiometry (DXA) or quantitative computed tomography (QCT) which provide surrogate measures for proximal femoral strength. However, proximal femoral strength can best be estimated explicitly by combining QCT with finite element (FE) analysis. To evaluate this technique for predicting hip fracture in older men and women, we performed a nested age- and sex-matched case-control study in the Age Gene/Environment Susceptibility (AGES) Reykjavik cohort. Baseline (pre-fracture) QCT scans of 5500 subjects were obtained. During 4-7 years follow-up, 51 men and 77 women sustained hip fractures. Ninety-seven men and 152 women were randomly selected as age- and sex-matched controls. FE-strength of the left hip of each subject for stance (F(Stance)) and posterolateral fall (F(Fall)) loading, and total femur areal bone mineral density (aBMD) were computed from the QCT data. F(Stance) and F(Fall) in incident hip fracture subjects were 13%-25% less than in control subjects (p ≤ 0.006) after controlling for demographic parameters. The difference between FE strengths of fracture and control subjects was disproportionately greater in men (stance, 22%; fall, 25%) than in women (stance, 13%; fall, 18%) (p ≤ 0.033), considering that F(Stance) and F(Fall) in fracture subjects were greater in men than in women (p < 0.001). For men, F(Stance) was associated with hip fracture after accounting for aBMD (p = 0.013). These data indicate that F(Stance) provides information about fracture risk that is beyond that provided by aBMD (p = 0.013). These findings support further exploration of possible sex differences in the predictors of hip fracture and of sex-specific strategies for using FE analysis to manage osteoporosis.

Effects of age and sex on the strength and cortical thickness of the femoral neck

A group of 48 men (22 aged 65-75 years, 26 aged 80-90 years) and 59 women (32 aged 65-75 years, 27 aged 80-90 years) were enrolled in the Age, Gene/Environment Susceptibility-Reykjavik study and imaged with in vivo volumetric Quantitative Computed Tomography (QCT) to investigate the effects of age and sex on femoral neck structure and strength. Femoral neck cross-sectional moment of inertia for bending directions near those of standing and walking (I(AP)), bending strength (M(y)), and axial compressive strength (F(y)) were computed at the location of minimum cross-sectional area (minCSA). Local cortical thickness was computed in the inferior femoral neck based on density profiles extending through the cortex of the minCSA femoral neck section. Multivariate models accounting for height, weight, and age group (younger or older) showed that men had a 46% higher M(y) and a 23% higher F(y) than women, while women had a 13% thicker inferior cortex than men. Cortical thickness in the inferoposterior region of the femoral neck was significantly related to bending and axial strength after adjusting for overall volumetric bone mineral density. Both minCSA and I(AP) were higher in the older, gender-pooled age group, but F(y) and M(y) did not differ between the two age groups. The results suggest that age-related expansion of the femoral neck primarily occurs in the superior and inferior directions and helps maintain homeostasis of femoral neck stiffness and strength. The higher bending strength of the male femoral neck may partly explain why elderly men have a lower risk of hip fracture than elderly women.

Simple all-optical FFT scheme enabling Tbit/s real-time signal processing

A practical scheme to perform the fast Fourier transform in the optical domain is introduced. Optical real-time FFT signal processing is performed at speeds far beyond the limits of electronic digital processing, and with negligible energy consumption. To illustrate the power of the method we demonstrate an optical 400 Gbit/s OFDM receiver. It performs an optical real-time FFT on the consolidated OFDM data stream, thereby demultiplexing the signal into lower bit rate subcarrier tributaries, which can then be processed electronically.

Thyrotoxicosis in Iceland 1980-1982. An epidemiological survey

A nationwide survey of the incidence of clinical thyrotoxicosis in Iceland was made during the three-year period 1980-1982. An annual incidence of 23.6 per 100 000 inhabitants was found, females outnumbering males by 4.2:1; 72% of all patients were aged 20-49. Graves' disease was considered the cause in 83.3% of the patients.

Community screening for glucose intolerance in middle-aged Icelandic men. Deterioration to diabetes over a period of 71/2 years

A number of 2203 middle-aged Icelandic men (aged 34-61 years) participated in a health survey in Reykjavik in 1967-68. Blood glucose in the fasting state and during an oral glucose tolerance test (OGTT) showed a unimodal distribution with a slight skewness towards higher values. A positive age gradient was established, which showed an increment of about 7 mg/dl per decade in capillary blood sugar values at 11/2 hours after a 50 g oral glucose load. The age gradient was mostly independent of age-related changes in body weight. A 71/2 year followup of the eligible participants (response rate 80%) showed an overall 1% incidence of metabolic deterioration to "overt diabetes" during this period. Those with positive screening tests (50 g OFTT) at baseline were at greater risk of developing diabetes, but the incidence of deterioration in this group was low, about 1% per year. The progression to diabetes was significantly related to body weight at baseline, suggesting that weight reduction might be beneficial in individuals showing impaired glucose tolerance at medical examination. This study, however, lends support to recent reports showing that mildly impaired glucose tolerance cannot be equated with early diabetes.

Factors associated with elevated or blunted PTH response in vitamin D insufficient adults

OBJECTIVES

The purpose of this study was to examine factors associated with high or low parathyroid hormone (PTH) levels in relationship to vitamin D insufficiency.

DESIGN

This was a cross-sectional study consisting of 516 healthy men and women, aged 30-85, all Caucasians with vitamin D insufficiency [serum 25(OH)D<45 nmol L(-1)]. The group was divided into quartiles by PTH levels and the highest and lowest quartiles were compared with regard to various factors likely to affect calcium metabolism. We used stepwise multivariable logistic regression to determine the independent association between PTH levels and other variables for men and women separately.

RESULTS

We found that men in the lowest PTH quartile were significantly younger, had less energy intake, lower body mass index (BMI) and better kidney function compared with the highest PTH quartile. They had also higher ionized calcium, insulin-like growth factor (IGF1) and testosterone and were more likely to smoke. Women within the lowest PTH quartile were younger, had lower BMI and magnesium values and higher IGF1 levels and were more likely to smoke. Stepwise multivariate regression showed that IGF1, testosterone and BMI were significantly associated with PTH in men (R(2)=0.472) but smoking, BMI and kidney function in women (R(2)=0.362).

CONCLUSIONS

Our results indicate that during vitamin D insufficiency, factors other than calcium and vitamin D may modify PTH response. These factors may be different between sexes and we have identified novel factors, IGF1 and testosterone in men which may be compensatory in nature and confirmed previous factors such as smoking, BMI and kidney function in women.

Increasing glucose levels and BMI predict future heart failure Experience from the Reykjavík Study

BACKGROUND

Heart failure is common in diabetes and ischaemic heart disease is the most likely link. Still, it has been suggested that the relation extends beyond such disease.

METHODS

7060 subjects with two or more visits in the Reykjavík Study were followed--during 30 years from 1967. All underwent oral glucose tolerance tests. Disease status was defined according to the glycaemic level and presence of heart failure. The incidence and predictive factors for these diseases were determined.

FINDINGS

Age and sex standardized incidence of heart failure was 5.3/1000/year, of diabetes 4.6/1000/year and abnormal glucose regulation 12.6/1000/year. Body mass index (BMI) and fasting glucose predicted the development of these conditions (p<0.001). Increasing fasting glucose by 1 mmol/l increased the risk for heart failure by 14% (p=0.04) after adjusting for IHD, BMI and other risk factors for CVD. There was a strong association between diabetes and heart failure, OR 3.0 (2.3-4.0), and abnormal glucose regulation and heart failure, OR 1.8 (1.5-2.3). Diabetes and heart failure were, however, not independent predictors of each other.

INTERPRETATION

There was an independent relationship between increases in fasting glucose and development of heart failure. BMI was a strong predictor of heart failure. Although fasting glucose and BMI were significant risk factors for glucose disturbances and heart failure the conditions themselves did not independently predict each other.

The Emerging Risk Factors Collaboration: analysis of individual data on lipid, inflammatory and other markers in over 1.1 million participants in 104 prospective studies of cardiovascular diseases

Many long-term prospective studies have reported on associations of cardiovascular diseases with circulating lipid markers and/or inflammatory markers. Studies have not, however, generally been designed to provide reliable estimates under different circumstances and to correct for within-person variability. The Emerging Risk Factors Collaboration has established a central database on over 1.1 million participants from 104 prospective population-based studies, in which subsets have information on lipid and inflammatory markers, other characteristics, as well as major cardiovascular morbidity and cause-specific mortality. Information on repeat measurements on relevant characteristics has been collected in approximately 340,000 participants to enable estimation of and correction for within-person variability. Re-analysis of individual data will yield up to approximately 69,000 incident fatal or nonfatal first ever major cardiovascular outcomes recorded during about 11.7 million person years at risk. The primary analyses will involve age-specific regression models in people without known baseline cardiovascular disease in relation to fatal or nonfatal first ever coronary heart disease outcomes. This initiative will characterize more precisely and in greater detail than has previously been possible the shape and strength of the age- and sex-specific associations of several lipid and inflammatory markers with incident coronary heart disease outcomes (and, secondarily, with other incident cardiovascular outcomes) under a wide range of circumstances. It will, therefore, help to determine to what extent such associations are independent from possible confounding factors and to what extent such markers (separately and in combination) provide incremental predictive value.

Smoking and a complement gene polymorphism interact in promoting cardiovascular disease morbidity and mortality

We have demonstrated previously that carriers of a genotype called C4B*Q0 (silent allele of the C4B gene) have a substantially increased risk to suffer from myocardial infarction or stroke, and are selected out from the healthy elderly population. Because smoking carries a major risk for cardiovascular disease (CVD), it seemed worthwhile to study if these two factors interact. Study 1 involved 74 patients with angina pectoris (AP), 85 patients with recent acute myocardial infarction (AMI) and 112 survivors of a previous AMI and 382 controls from Iceland. Study 2 involved 233 patients with severe CVD and 274 controls from Hungary. Smoking habits were registered for each subject. The number of C4A and C4B genes was determined by phenotyping or genotyping. Compared to controls, C4B*Q0 carrier frequency was significantly higher at diagnosis in Icelandic smokers with AP (P = 0.005) and AMI (P = 0.0003) and Hungarian smokers with severe coronary artery disease (P = 0.023), while no such difference was observed in non-smoking subjects. Age-associated decrease in C4B*Q0 observed previously in two remote Caucasian populations was found, in the present study, to be associated strongly with smoking, and to already occur in smokers after age 50 years both in Iceland and Hungary. Our findings indicate that the C4B*Q0 genotype can be considered as a major covariate of smoking in precipitating the risk for AMI and associated deaths.

Relationship between C-reactive protein and arterial stiffness in an asymptomatic population

Plasma concentration of high sensitive C-reactive protein (hsCRP) is used as a marker for inflammatory states and is directly correlated with the risk for coronary heart disease. Evidence concerning the role of inflammation in atheroma formation has been derived from several models of atherosclerosis. Inflammation should exert its adverse vascular effects by structural changes in the artery wall and consequently alterations in arterial elasticity, which could be detected already in asymptomatic early vascular disease. We hypothesized that CRP is related to large artery elasticity, but not to small artery elasticity in early vascular disease. Therefore, we examined the association between arterial stiffness of large and small arteries and inflammation in an asymptomatic population referred for primary prevention cardiovascular screening. Studies were performed in 391 subjects (age 21-82 years; 254 men, 137 women) who underwent screening at the Cardiovascular Disease Prevention Center. Large artery (C1) and small artery (C2) elasticity indices were obtained by the CVProfiler 2000 (HDI, Eagan, MN, USA). After overnight fasting, venous samples were taken for measurement of hsCRP, lipids, glucose. There was a significant inverse correlation between hsCRP (0.29 +/- 0.40 mg/dl) and C1 (16.7 +/- 5.8 ml/mmHg), r = -0.133, P = 0.01; there was no significant correlation between hsCRP and C2 (6.6 +/- 3.2 ml/mmHg). C2, but not hsCRP, was inversely correlated with age, abnormal lipids and glucose, whereas C1, but not hsCRP, was inversely correlated with age and systolic blood pressure (SBP). In multiple regression analysis, the relationship between hsCRP and C1 was not affected by age, body mass index, SBP, serum glucose or lipids. In conclusion, these findings support the hypothesis that hsCRP, a marker for acute and low-grade inflammation, is associated with large artery but not with small artery elasticity in asymptomatic individuals undergoing primary prevention cardiovascular screening.

Physical activity in the post-pubertal period is associated with maintenance of pre-pubertal high bone density - a 5-year follow-up

OBJECTIVE

To evaluate the association between physical activity (PA) and skeletal growth in girls during adolescence.

DESIGN

A 5-year, observational, population-based study (Reykjavik, Iceland).

SUBJECTS

Seventy-eight Caucasian girls, mean age 13.4+/-1.0 (mean+/-SD) years at baseline.

METHODS

Bone mineral density (BMD, g/cm2) and bone width (cm) were measured in the forearm by single-photon absorptiometry at baseline and with dual-energy X-ray absorptiometry after 3 and 5 years, when lumbar spine, femoral neck (FN) and total body were also evaluated. Half of the physically active girls were compared with the other half of less active girls.

RESULTS

BMD in physically active girls was higher in the forearm at both baseline (P=0.001) and after 5 years (P=0.04) in comparison with less active girls. BMD was higher for the total body (P=0.0001), spine L2-L4 (P=0.02) and FN (P=0.002) in the active girls at age 18. The accrual of forearm BMD and bone width from age 13 to 18 was no different when comparing the two groups.

CONCLUSIONS

Pre-pubertal PA is associated with high BMD at age 13 and continued PA is associated with maintenance of high BMD until age 18.

Fifteen percent of myocardial infarctions and coronary revascularizations explained by family history unrelated to conventional risk factors. The Reykjavik Cohort Study

Aims To examine the relationship between history of myocardial infarction in first-degree relatives and the risk of developing coronary heart disease (myocardial infarction or coronary revascularization). Methods and Results A total of 9328 males and 10062 females, randomly selected residents of the Reykjavik area, aged 33-81 years, were examined in the period from 1967 to 1996 in a prospective cohort study. Cardiovascular risk assessment was based on characteristics at baseline. Information on history of myocardial infarction in first-degree relatives was obtained from a health questionnaire. Mean follow-up was 18 and 19 years for men and women, respectively. During follow-up 2700 men and 1070 women developed coronary heart disease. Compared with subjects without a family history, the hazard ratio of coronary heart disease was 1.75 (95% confidence interval, CI, 1.59-1.92) for men and 1.83 (95% CI, 1.60-2.11) for women, with one or more first-degree relatives with myocardial infarction. The risk factor profile was significantly worse in individuals with a positive family history. After allowance for these risk factors, the hazard ratio was still highly significant, 1.66 (CI, 1.51-1.82) and 1.64 (CI, 1.43-1.89) for men and women, respectively. Family history of myocardial infarction was attributed to 15.1% of all cases of coronary heart disease in men and 16.6% in women, independent of other known risk factors. Conclusion Family history of myocardial infarction increases the risk of developing coronary heart disease in both men and women and is largely independent of other classic risk factors. Approximately 15% of all myocardial infarctions can be attributed to familial factors that have not been measured in the study or remain to be elucidated.

Adrenocorticotrophic hormone exerts marked lipid-lowering effects in simvastatin-treated patients

OBJECTIVE

Recently, it was reported that treatment with adrenocorticotrophic hormone (ACTH) has a strong lipid-lowering effect in healthy individuals. The mechanism behind this has not been established. The aim of the present investigation was to study the effect of ACTH on the plasma lipoprotein pattern in patients treated with a 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitor.

DESIGN

The ACTH treatment was given to 10 patients who were on long-term treatment with simvastatin 40 mg daily. ACTHI-24 was administered at the dose of 1 mg daily for four consecutive days. Blood samples for analyses of lipids, lipoproteins and apolipoproteins were collected before and after treatment. Second baseline was obtained 2 weeks after the end of treatment.

RESULTS

The serum concentrations of cholesterol, triglycerides, low density lipoprotein (LDL) cholesterol, apolipoprotein B and lipoprotein(a) fell significantly by 16, 23, 23, 10 and 38%, respectively. The serum apolipoprotein E concentration increased significantly by 39%; the fraction that was not associated with apolipoprotein B increased by 47% whereas the fraction that was did not change significantly. There were no changes in the serum concentrations of high density lipoprotein (HDL) cholesterol and apolipoprotein AI. At the second baseline, the lipid variables had generally returned to previous levels.

CONCLUSIONS

In patients on long-term simvastatin treatment, ACTH had marked lowering effects on the lipoproteins that contain apolipoprotein B. Moreover, the serum apolipoprotein E concentration increased significantly in response to ACTH treatment.

The -629C>A polymorphism in the CETP gene does not explain the association of TaqIB polymorphism with risk and age of myocardial infarction in Icelandic men

The aim of this study was to examine whether the well-established effect of the common TaqIB polymorphism in intron 1 of the gene for cholesterol ester transfer protein (CETP) on high density lipoprotein cholesterol (HDL-C) concentration and increased risk of myocardial infarction (MI), could be explained by the recently identified -629C>A functional polymorphism in the promoter. Non-fatal MI cases (388 male) and a control group of 794 healthy men were recruited from the 30 year long prospective Reykjavik Study. In the healthy men the frequency of the TaqIB B2 allele was 0.47 (95% CI: 0.44-0.50) and there was a strong allelic association with the -629A allele (D=-0.21, P<0.0001), which had a frequency of 0.52 (95% CI: 0.49-0.56). B2B2 homozygotes displayed 15% higher HDL-C levels than subjects homozygous for the B1 allele (P<0.0001). Homozygotes for the -629A allele displayed 14% higher HDL-C concentrations than subjects homozygous for the -629C allele (P<0.0001). The frequencies of the alleles associated with lower HDL-C were significantly higher in cases compared with controls, 0.59 versus 0.53 (TaqIB B1) and 0.52 versus 0.48 (-629 C) respectively (P<0.05 for both). There was a significantly higher risk for MI in B1B1 homozygotes (OR=1.44, 95% CI: 1.10-1.87, P<0.01), compared to the other genotypes combined. This was not observed for the CC homozygotes (OR=1.16, 95% CI: 0.87-1.54). In addition, homozygotes for the TaqI B2 allele experienced a first MI 2 years later than men with other genotypes, 59 versus 61 years (P<0.05). This effect was not seen for the promoter polymorphism. These results strongly confirm the role of the CETP gene and the TaqIB variant as a risk factor for MI and suggest that another functional polymorphism is yet to be discovered in the CETP gene, that will explain the effect on MI associated with TaqIB observed in this study.

Successful management of a B-type cardiac allograft into an O-type man with 3(1/2)-year clinical follow-up

BACKGROUND

In May 1997, a 19-year-old male patient of histo-blood group type O suffering from congenital end-stage heart failure accidentally received a cardiac allograft of type B and is still alive in fair condition.

METHODS

In addition to conventional immunosuppressive therapy, plasma exchange (PEX), extracorporeal immunoabsorption (EIA), intravenous immunoglobulins (IVIG), and C1 inhibitor were used.

RESULTS

Such treatment successfully reduced both IgM and IgG anti-B levels and complement hyperactivity and allowed to reach the state of accommodation without obvious signs of rejection. The patient has been surviving for 42 months; retransplantation with an O-type heart remained unnecessary.

CONCLUSION

Humoral rejection has been avoided in this patient, with PEX, EIA, IVIG, and C1 inhibitor substantially contributing to this success. With future availability of such combined therapies, preferably before transplantation, vascular rejection events caused by preformed antibodies and complement (ABO mismatch or anti-HLA) could be prevented or treated.

Ketoconazole and pulmonary failure after esophagectomy: a prospective clinical trial

Thromboxane is a key mediator in pulmonary injury after esophageal resection. In this prospective trial we studied the clinical course and development of pulmonary alterations in patients undergoing esophagectomy and prophylactic treatment with a thromboxane synthase inhibitor. Thirty-eight consecutive patients undergoing esophageal resection were treated pre- and perioperatively with 3 x 200 mg ketoconazole. The clinical course was studied and pulmonary function was assessed according to the Murray score. A historical group of 118 patients undergoing esophagectomy for benign and malignant esophageal diseases served as controls. Patients in both groups were similar in terms of age, sex, and preoperative pulmonary function, as well as in the anesthetic and surgical procedures performed. However, in the ketoconazole group, more patients were at risk of pulmonary failure by receiving neoadjuvant radiochemotherapy (22/38) or undergoing thoracotomies (33/38) than control subjects (14/118 and 80/118, P < 0.05). Two out of 38 ketoconazole-treated patients developed acute lung injury after esophagectomy, as did 20/118 control patients (P < 0.05). This prospective non-randomized clinical study (in patients subjected to esophagectomy) provides further evidence that prophylactic thromboxane synthase inhibition by ketoconazole reduces the incidence of acute lung injury in patients at risk.

Liquorice-induced rise in blood pressure: a linear dose-response relationship

To clarify the dose-response and the time-response relationship between liquorice consumption and rise in blood pressure and explore the inter-individual variance this intervention study was designed and executed in research laboratories at University hospitals in Iceland and Sweden. Healthy, Caucasian volunteers who also served as a control for himself/herself consumed liquorice in various doses, 50-200 g/day, for 2-4 weeks, corresponding to a daily intake of 75-540 mg glycyrrhetinic acid, the active substance in liquorice. Blood pressure was measured before, during and after liquorice consumption. Systolic blood pressure increased by 3.1-14.4 mm Hg (P < 0.05 for all), demonstrating a dose-response but not a time-response relationship. The individual response to liquorice followed the normal distribution. Since liquorice raised the blood pressure with a linear dose-response relationship, even doses as low as 50 g of liquorice (75 mg glycyrrhetinic acid) consumed daily for 2 weeks can cause a significant rise in blood pressure. The finding of a maximal effect of liquorice after only 2 weeks has important implications for all doctors dealing with hypertension. There does not seem to be a special group of responders since the degree of individual response to liquorice consumption followed the normal distribution curve.

Increased bone mineral density in a population-based group of 70-year-old women on thiazide diuretics, independent of parathyroid hormone levels

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 < 0.01) and 5.4% greater in the whole skeleton (P < 0.01) amongst thiazide users than in controls, reduced to 7.6% (P < 0.02) and 4.5% (P < 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.

Common founder mutation in the LDL receptor gene causing familial hypercholesterolaemia in the Icelandic population

Haplotype analysis in 18 apparently unrelated families with familial hypercholesterolaemia (FH) in Iceland has identified at least five different chromosomes cosegregating with hypercholesterolaemia. The most common haplotype was identified in 11 of the 18 families, indicating a responsible for FH in the Icelandic population. By using single-strand conformation polymorphism (SSCP) and direct sequencing of amplified DNA, we identified a novel mutation (a T to a C) in the second nucleotide in the 5' part of intron 4 in the LDL receptor gene. This mutation was present in approximately 60% of the FH families (10/18), supporting the prediction of a common founder. These families could be traced to a common ancestor in half of the cases by going back no further than the eighteenth century. The mutation was predicted to affect correct splicing of exon 4, and analysis at the cellular level demonstrated an abnormal mRNA containing intron 4 sequence in lymphoblastoid cells from a patient carrying this mutation. Translation of the mRNA would lead to a premature stop codon and a truncated nonfunctional protein of 285 amino acids. The novel sequence change created a new restriction site for the restriction endonuclease NlaIII, and using this assay, 29 unrelated individuals with possible FH attending a lipid clinic for treatment were examined for this mutation. Two individuals in this group of patients were found to be carriers of this mutation, supporting the suggestion of a founder mutation. Using this assay for the detection of FH in the Icelandic population should identify > 60% of these individuals.

Effects of sleep deprivation on neural circulatory control

Effects of sleep deprivation on neural cardiovascular control may have important clinical implications. We tested the hypothesis that sleep deprivation increases heart rate, blood pressure, and sympathetic activity and potentiates their responses to stressful stimuli. We studied 8 healthy subjects (aged 40+/-5 years, 6 men and 2 women). Blood pressure, heart rate, forearm vascular resistance, and muscle sympathetic nerve activity were measured at rest and during 4 stressors (sustained handgrip, maximal forearm ischemia, mental stress, and cold pressor test). Measurements were obtained twice, once after normal sleep and once after a night of sleep deprivation. All measurements were obtained in a blinded, randomized manner. In comparison with normal sleep, sleep deprivation resulted in an increase in blood pressure (normal sleep versus sleep deprivation=82+/-8 versus 86+/-7 mm Hg, mean+/-SEM, P=0.012) and a decrease in muscle sympathetic nerve activity (normal sleep versus sleep deprivation=28+/-6 versus 22+/-6 bursts/min, P=0.017). Heart rate, forearm vascular resistance, and plasma catecholamines were not significantly changed by sleep deprivation, nor did sleep deprivation affect autonomic and hemodynamic responses to stressful stimuli. Sleep deprivation results in increased resting blood pressure, decreased muscle sympathetic nerve activity, and no change in heart rate. Thus, the pressor response to sleep deprivation is not mediated by muscle sympathetic vasoconstriction or tachycardia.

The association between parathyroid hormone, vitamin D and bone mineral density in 70-year-old Icelandic women

Parathyroid hormone (PTH) may be an important determinant of cortical bone remodeling in the elderly. Vitamin D status is one of the determining factors in this relationship. The aim of this study was to quantify the relationship between serum PTH, vitamin D and bone mineral density (BMD) in elderly women in Reykjavik (64 degrees N), where daily intake of cod liver oil is common and mean calcium intake is high. In PTH correlated inversely with 25(OH)D (r = -0.26, p<0.0 1). In multivariate analysis PTH correlated inversely with whole body BMD (mostly cortical bone) (R2 = 2.2%, p = 0.04) but not with the lumbar spine BMD, reflecting more cancellous bone. No association was found between 25(OH)D levels and BMD at any site in univariate or multivariate analysis. Osteocalcin, a measure of bone turnover, was negatively associated with BMD and this association remained significant when corrected for PTH levels. In summary, in this fairly vitamin D replete population with high calcium intake, PTH was negatively associated with total body BMD. We infer that suppression of PTH may reduce cortical bone loss, but other factors are likely to contribute to age-related bone remodeling and osteoporosis.

[Bilateral oophorectomy before menopause. Late effects on quality of life, lipid metabolism and bone mass.]

OBJECTIVE

Oophorectomy in premenopausal women may profoundly affect health. This study was done to investigate whether it had influenced the quality of life, lipid metabolism and bone mass if removal of the ovaries in premenopausal women was performed more than 15 years ago.

MATERIAL AND METHODS

Operation records from the Department of Obstetrics and Gynecology at the National University Hospital, Reykjvík, were scruti-nized to find all women who during 1977-1984 had a bilateral oophorectomy performed at less than 47 years of age at the time of operation. A control group of age-matched women, who during the same period had undergone a hysterectomy with preservation of the ovaries, was chosen. Women with malignant and chronic disabling diseases were excluded. The participants answered 36 standardized questions relating to menopausal symptoms, hormonal use and smo-king. Mesurements of total serum cholesterol, HDL (high density lipoprotein) and LDL (low density lipoprotein) cholesterol, triglycerides and calcium and fasting urine calcium and creatinine, were performed. Bone mineral density was assessed by dual energy X-ray absorptiometry in the lumbar spine, left hip and femoral neck.

RESULTS

Thirty-four patients and equally many controls were identified. Fifty women agreed to participate, but two did not attend for the investigation, giving a total of 26 cases and 22 controls. Mean age at the time of operation was 43.3 years for cases and 43.5 and controls. The difference in the duration of hormone use (11.6 and 8.9 years) was not significant. Of the 36 questions on climacteric symptoms there was a significant difference between the groups in only one. Cases and controls were not different with regard to serum lipids and bone mineral density. Mean values of bone mineral density in both groups were within the normal limits for an age-matched general population.

CONCLUSIONS

Women who underwent removal of the ovaries before 47 years of age, more than 15 years later, were not shown to have suffered more from longterm effects of estrogen deficiency than age-matched women who had undergone hysterectomy with preservation of the ovaries. A relatively long duration of estrogen use may be the main reason for this outcome.