Relationship of height, weight and body mass index to the risk of hip and knee replacements in middle-aged women

OBJECTIVES

To examine the effect of height, weight and body mass index (BMI) on the risk of hip and knee replacement in middle-aged women.

METHODS

In a prospective cohort study 490 532 women aged 50-69 yrs who were recruited in the UK in 1996-2001 were followed over 2.9 yrs for incident primary hip and knee replacements.

RESULTS

Height, weight and BMI were all associated with the risk of hip and knee replacement. Comparing the tallest group (>or=170 cm) with the shortest (<155 cm) the relative risks were 1.90 (95%CI 1.55-2.32) for hip replacement and 1.55 (95%CI 1.19-2.00) for knee replacement. Comparing the heaviest group (>or=75 kg) with the lightest (<60 kg) the relative risks of hip and knee replacement were 2.37 (95%CI 2.04-2.75) and 9.71 (95%CI 7.39-12.77), respectively. Comparing obese women (BMI >or= 30 kg/m(2)) to women with a BMI < 22.5 kg/m(2), the relative risks for hip and knee replacement were 2.47 (95%CI 2.11-2.89) and 10.51 (95%CI 7.85-14.08), respectively. These effects did not vary according to age, education, alcohol and tobacco consumption, or with use of hormonal therapies. Currently, an estimated 27% of hip replacements and 69% of knee replacements in middle-aged women in the UK are attributable to obesity.

CONCLUSION

In middle-aged women, the risk of having a hip or knee replacement increases with both increasing height and increasing BMI. From a clinical perspective, relatively small increases in average BMI among middle-aged women are likely to have a substantial impact on the already increasing rates of joint replacement in the UK.

Use of beta-blockers and the risk of hip/femur fracture in the United Kingdom and The Netherlands

Data from in vivo studies have indicated a role for beta-blockers in the prevention of bone loss. Some epidemiological studies have found protective effects of beta-blockers on fracture risk. However, there is limited information on the association with cumulative dose and type of beta-blockers used. We conducted two case-control studies using data from the UK General Practice Research Database (GPRD) and the Dutch PHARMO Record Linkage System (RLS). Cases were patients with a first hip or femur fracture; controls were individually matched on practice/region, gender, year of birth, and calendar time. Current use of beta-blockers was defined as a prescription in 90 days before the index date. We adjusted for medical conditions and drugs associated with falling or bone mineral density. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using conditional logistic regression analysis. The study population included 22,247 cases and controls in the GPRD and 6,763 cases and 26,341 controls in the PHARMO RLS. Current use of beta-blockers was associated with a reduced risk of hip/femur fracture in both the GPRD (adjusted OR = 0.82, 95% CI 0.74-0.91) and PHARMO RLS (adjusted OR = 0.87, 95% CI 0.80-0.95) study populations. However, this reduction of risk was not associated with cumulative dose, lipophilicity, or receptor selectivity of beta-blockers. The protective effect of beta-blockers was only present among patients with a history of use of other antihypertensive agents (GPRD adjusted OR = 0.72, 95% CI 0.64-0.83; PHARMO RLS adjusted OR = 0.76, 95% CI 0.67-0.86) but not in patients using beta-blockers only (GPRD adjusted OR = 0.97, 95% CI 0.82-1.14; PHARMO RLS adjusted OR = 1.01, 95% CI 0.90-1.14). Also, in patients with a history of use of other antihypertensive agents, no dose-response relationship with beta-blocker use was found. The effect was constant with cumulative dose and the OR was below 1.0 even among patients who just started treatment with beta-blockers. As the mechanism by which beta-blockers could influence bone mineral density is likely to need some time to exert a clinically relevant effect, all these finding suggests that the association between beta-blockers and fracture risk is not causal.

Use of inhaled and oral glucocorticoids, severity of inflammatory disease and risk of hip/femur fracture: a population-based case-control study

BACKGROUND

Patients using higher dosages of inhaled or oral glucocorticoids (GCs) have an increased risk of hip/femur fractures. The role of the underlying disease in the aetiology of this increased risk has not been widely studied.

OBJECTIVE

To evaluate the contribution of the underlying disease to the risk of hip/femur fracture in patients using inhaled or oral GCs.

DESIGN AND SUBJECTS

A case-control study within the Dutch PHARMO-RLS database was conducted. Cases (n = 6763) were adult patients with a first hip/femur fracture during enrolment. Each case was matched to four controls by age, gender and region.

RESULTS

The risk of hip/femur fracture increased with current use of inhaled GCs (crude OR 1.30, 95% CI:1.16-1.47) and with current use of oral GCs (crude OR 1.66, 95% CI: 1.46-1.90). After adjustment for disease severity, the risk of hip/femur fracture was no longer statistically significantly increased in inhaled GC users (adjusted OR 1.08, 95% CI: 0.91-1.27), whilst it remained elevated in oral GC users (adjusted OR 1.43, 95% CI: 1.22-1.67). Patients using inhaled GCs without any exposure to oral GCs had no increased risk of fracture (adjusted OR 0.98, 95% CI: 0.79-1.22).

CONCLUSION

Inhaled GC users had no increased risk of femur/hip fracture after adjustment for underlying disease severity. Our data suggest that, even at higher dosages, inhaled GC use is not an independent risk factor for fracture. In contrast, oral GC use was associated with an increased risk of fracture, which was not fully explained by the underlying disease severity.

Parental determinants of neonatal body composition

BACKGROUND

The prevalence of both childhood and adult obesity is rising in the developed world, and there is increasing interest in its underlying causes. A number of studies suggest a positive relationship between birth weight and childhood body mass index, but less is known about specific prenatal environmental influences on more direct measures of obesity. We used data from the Southampton Women's Survey to investigate parental influences on neonatal body composition ascertained by dual x-ray absorptiometry.

METHODS

Participating mothers were characterized in detail (anthropometry, lifestyle, diet) before and during pregnancy; information was also obtained on their partners. The offspring underwent assessment of fat and lean body mass by dual x-ray absorptiometry within 2 wk of birth. Linear regression methods were used to explore the parental determinants of neonatal body composition.

RESULTS

Complete data were available for 448 mother-offspring pairs. Taller women and those with higher parity had offspring with increased birth weight, fat, and lean mass (P < 0.05). Mothers who were taller, of greater parity, had greater fat stores, or walked more slowly also had offspring with greater proportionate body fat at birth (all P < 0.05). There was a weaker trend toward lower percentage fat and greater percentage lean in the offspring of mothers who smoked during pregnancy.

CONCLUSION

Maternal size, parity, smoking history, walking speed, and fat stores are independent determinants of neonatal body composition. If these influences are shown to have persisting effects on body composition through to adulthood, they point to novel public health interventions early in life to prevent later obesity.

Antipsychotics and cognitive decline in Alzheimer's disease: the LASER-Alzheimer's disease longitudinal study

OBJECTIVE

To investigate in a longitudinal cohort of people with Alzheimer's disease whether taking antipsychotics is associated with more rapid cognitive deterioration.

METHOD

From a sample of 224 people with Alzheimer's disease recruited as epidemiologically representative, those taking antipsychotic drugs for more than 6 months were compared with those who were not, in terms of change in three measures of cognition. The effects of potential mediators and confounders (demographic factors, neuropsychiatric symptoms, cognitive severity and cholinesterase inhibitors) were also examined.

RESULTS

No significant difference was observed in cognitive decline between those taking antipsychotics (atypical or any) and others on any measure of cognition. The only predictor of more cognitive decline was greater baseline cognitive severity (B = 3.3, 95% confidence interval 0.6 to 6.1, t = 2.4, p<0.05). Although mortality was higher in those treated with antipsychotics, this reflected their greater age and severity of dementia. The results were the same when the whole cohort was included rather than the select group with potential to change who had been taking antipsychotics continuously.

CONCLUSIONS

In this, the first cohort study investigating the effects of atypical antipsychotics on cognitive outcome in Alzheimer's disease, those taking antipsychotics were no more likely to decline cognitively over 6 months. Although clinicians should remain cautious when prescribing antipsychotic drugs to people with Alzheimer's disease, any increase in cognitive deterioration is not of the magnitude previously reported. There is a need for cohort studies that follow up patients from first prescription in clinical practice for a period of months rather than weeks to determine "real-life" risks and benefits.

Relationship between personality and satisfaction with the dentition in tooth wear patients

This study was undertaken to identify whether personality traits had any relationship with patients' satisfaction with their dentition in tooth wear cases. One hundred tooth wear patients and one hundred controls were recruited into the study. A Dental Impact on Daily Living questionnaire was used to assess impact of tooth wear on day to day life and satisfaction with the dentition. An ordinal scale was used to assess tooth wear severity in tooth wear patients. The NEO Five Factor inventory was used to assess personal profiles. Tooth wear patients were less satisfied with their dentition, had higher Neuroticism, lower Extraversion, and higher Openness than the controls.

Clinical assessment of the long-term risk of fracture in patients with rheumatoid arthritis

OBJECTIVE

To determine whether patients with rheumatoid arthritis (RA) have an increased risk of fracture, and to estimate their long-term absolute fracture risk.

METHODS

We studied patients with RA ages >or=40 years in the British General Practice Research Database, each matched by age, sex, calendar time, and practice to 3 control patients. Incident fractures, as recorded in the computerized medical records, were ascertained over a median followup of 7.6 years. The fracture rate in RA patients compared with controls was adjusted for smoking, body mass index (BMI), and several clinical risk factors, and Cox proportional hazards models were used to calculate the relative risk (RR) of fracture in RA. A risk score was then developed to provide an estimate of the 5- and 10-year fracture risk among RA patients.

RESULTS

There were 30,262 patients with RA, of whom 2,460 experienced a fracture during followup. Compared with controls, patients with RA had an increased risk of fracture, which was most marked at the hip (RR 2.0, 95% confidence interval [95% CI] 1.8-2.3) and spine (RR 2.4, 95% CI 2.0-2.8). Indicators of a substantially elevated risk of fracture (at the hip) included >10 years' duration of RA (RR 3.4, 95% CI 3.0-3.9), low BMI (RR 3.9, 95% CI 3.1-4.9), and use of oral glucocorticoids (RR 3.4, 95% CI 3.0-4.0). Modeling of the long-term risk profiles revealed that, for example, in a woman age 65 years with longstanding RA whose risk factors also included low BMI, a history of fracture, and frequent use of oral glucocorticoids, the 5-year risk of hip fracture was 5.7% (95% CI 5.3-6.1%).

CONCLUSION

Patients with RA are at increased risk of osteoporotic fractures. This increased risk is attributable to a combination of disease activity and use of oral glucocorticoids.

PARL Leu262Val is not associated with fasting insulin levels in UK populations

AIMS/HYPOTHESIS

PARL, the gene encoding presenilins-associated rhomboid-like protein, maps to chromosome 3q27 within a quantitative trait locus that influences components of the metabolic syndrome. Recently, an amino acid substitution (Leu262Val, rs3732581) in PARL was associated with fasting plasma insulin levels in a US white population (N=1031). This variant was also found to modify the positive association between age and fasting insulin. The aim of this study was to test whether these findings could be replicated in two UK population-based cohorts.

METHODS

Participants from the Medical Research Council Ely and Hertfordshire cohort studies were genotyped for this variant using a SNaPshot primer extension assay and Taqman assay respectively. Full phenotypic and genotypic data were available for 3,666 study participants.

RESULTS

Based on a dominant model, we found no association between the Leu262Val polymorphism and fasting insulin levels (p=0.79) or BMI (p=0.98). We did not observe the previously reported interaction between age and genotype on fasting insulin (p=0.14).

CONCLUSIONS/INTERPRETATION

Despite having greater statistical power, our data do not support the previously reported association between PARL Leu262Val and fasting plasma insulin levels, a measure of insulin resistance. Our findings indicate that this variant is unlikely to be an important contributor to insulin resistance in UK populations.

Is hand-held dynamometry useful for the measurement of quadriceps strength in older people? A comparison with the gold standard Bodex dynamometry

BACKGROUND

The lower limb muscle strength is an important determinant of physical function in older people. However, measurement in clinical and epidemiological settings has been limited because of the requirement for large-scale equipment. A protocol using a novel, versatile hand-held dynamometer (HHD) has been developed to measure the quadriceps strength in a supine position.

OBJECTIVE

The objective of this study was to assess the validity of this new methodology for measuring the lower limb muscle strength compared to the gold standard Biodex dynamometer.

METHODS

The supine quadriceps strength was measured twice with each of the Biodex and the HHD in 20 men and women, aged 61-81 years, on their non-dominant leg. The agreement between the peak torques obtained by Biodex and HHD was analyzed.

RESULTS

The mean peak Biodex and HHD results were 83.4 +/- (SD) 28.0 Nm and 68.9 +/- 19.6 Nm, respectively. The HHD undermeasured the quadriceps strength by an average of 14.5 Nm (95% CI 8.5, 20.6) compared to the Biodex, and this effect was most marked in the strongest participants. Nevertheless, there was a good correlation between the measures (r = 0.91, p < 0.0001). Classification of individuals into tertiles of muscle strength showed good agreement between the two methods (Kappa = 0.69, p < 0.0001).

CONCLUSIONS

Our findings suggest that the HHD using a supine positioning offers a feasible, inexpensive, and portable test of quadriceps muscle strength for use in healthy older people. It underestimates the absolute quadriceps strength compared to the Biodex particularly in stronger people, but is a useful tool for ranking muscle strength of older people in epidemiological studies. It may also be of value for quick and objective assessment of physical function in the clinical setting.

Specialist home-based nursing services for children with acute and chronic illnesses

BACKGROUND

Specialist paediatric home-based nursing services have been proposed as a cost-effective means of reducing trauma resulting from hospital admissions, while enhancing primary care and reducing length of hospital stay.

OBJECTIVES

To evaluate specialist home-based nursing services for children with acute and chronic illnesses.

SEARCH STRATEGY

Electronic searches were made of CENTRAL (Cochrane Central Register of Controlled Trials) 2005 (Issue 2); MEDLINE (1966 to August 2005); EMBASE (1980 to August 2005); PsycINFO (1887 to August 2005); CINAHL (1982 to August 2005); Sociological Abstracts (1963 to August 2005). Optimally sensitive search strategies for randomised controlled trials (RCTs) were combined with medical subject headings and text words specific for ambulatory paediatrics, nursing outreach and 'hospital in the home', and no language restrictions were applied.

SELECTION CRITERIA

RCTs of children aged 0-18 with acute or chronic illnesses allocated to specialist home-based nursing services compared with conventional medical care. Outcomes included utilisation of health care, physical and mental health, satisfaction, adverse health outcomes and costs.

DATA COLLECTION AND ANALYSIS

Meta-analysis was not appropriate because of the clinical diversity and lack of common outcomes measures

MAIN RESULTS

1655 titles yielded 5 RCTs with a total of 771 participants. Participants, interventions and outcomes were diverse. No significant differences were reported in health outcomes; two studies reported improvements in child and parental anxiety; one study reported no significant difference in readmissions; two studies reported significantly fewer bed days; increased satisfaction was reported ; home care was more costly for service providers, but less expensive for parents.

AUTHORS' CONCLUSIONS

While current research does not provide definitive support for specialist home-based nursing services in reducing access to hospital services or length of stay, preliminary results show no adverse impact on physical health outcomes and a number of papers reported improved satisfaction with home-based care. Further trials are required, measuring health, satisfaction, service utilisation and long-term costs.

A simple clinical score for estimating the long-term risk of fracture in post-menopausal women

BACKGROUND

Simple tools are needed to identify patients at high risk of fracture.

AIM

To develop a simple clinical tool for assessing 5-year risk of fracture.

DESIGN

Cohort study.

METHODS

The study population consisted of all women aged 50+ included in the THIN Research Database (containing computerized medical records of UK general practices). Using Cox proportional hazards models, a risk score was initially estimated from age, body mass index, and clinical risk factors. The 5-year risk of fracture (survival function) was estimated for each score.

RESULTS

The study population included 366 104 women aged > or = 50 years (mean follow-up 5.8 years). Of these, 6453 suffered a hip fracture. Several characteristics independently contributed to the fracture risk score (age, body mass index, fracture and fall history, previous diagnoses and use of medication). The 5-year risks for hip fracture for patients with total scores of 10, 30 and 50 were 0.3% (95%CI 0.3-0.4%), 2.2% (95%CI 2.1-2.2%), and 13.1% (95%CI 12.5-13.7%), respectively. A woman aged 65 years with low BMI and a history of both fracture and falling would have a hip fracture risk score of 37, with a corresponding 5-year risk for a hip fracture of 4.1% (4.0-4.2%). The risk score was validated and tested in another population (from GPRD), with a good concurrence between predicted and observed risks of fracture.

DISCUSSION

This risk score predicts the long-term risk of fracture, and could be used for targeting patients for further investigation, such as bone densitometry.

Individual fracture risk and the cost-effectiveness of bisphosphonates in patients using oral glucocorticoids

OBJECTIVES

There are few data on the cost-effectiveness of bisphosphonates with oral glucocorticoids (GCs). An individual patient-based pharmaco-economic model was developed.

METHODS

Data were obtained from a cohort of oral GC users aged 40+ (n = 190 000) in the UK General Practice Research Database. Individualized fracture and mortality risks were calculated specific for age, sex, daily and cumulative GC dose, indication and other clinical risk factors. UK costs of medication and direct costs of fracture were obtained from National Institute for Clinical Excellence and used to estimate costs per quality-adjusted life-year (QALY) gained and fracture prevented for bisphosphonates in patients treated for 5 yrs with GCs.

RESULTS

With the use of 5 mg GCs daily, the cost per one QALY gained with bisphosphonates was 41k UK pounds (95% confidence intervals 22-72k) in women aged <60 [men 40k pounds (29-54k)], 17k pounds (13-24k) in women aged 60-79 [men 43k pounds (31-60k)], 5k pounds(3-6k) in women aged 80+ [men 35k pounds (25-46k)]. With 15 mg GC, these figures were 17k pounds (14-21k), 13k pounds (10-16k) and 15k pounds (9-26k) in women and 22k pounds (17-26k), 34 pounds (23-53k) and 33k pounds (27-42k) in men, respectively. When stratifying by overall fracture risk and life expectancy at the start of GC therapy, cost per QALY increased with decreasing life expectancy. Patients with rheumatoid arthritis had comparatively better cost-effectiveness, given higher fracture risk and better life expectancy.

CONCLUSIONS

The cost-effectiveness of bisphosphonates varied substantially. Bisphosphonates can be considered cost-effective in patients with higher fracture risks, such as elderly patients (with a life expectancy over 5 yrs), and younger patients with a fracture history, low body mass index, rheumatoid arthritis or using high GC doses.

Characterization of patients with an inadequate clinical outcome from osteoporosis therapy: the Observational Study of Severe Osteoporosis (OSSO)

BACKGROUND

Osteoporotic fractures remain a major public health problem. Currently available osteoporosis therapies significantly reduce the risk of fractures, but up to 50% of patients have an inadequate clinical outcome to therapy.

AIM

To describe the clinical and quality of life (QOL) of a study population meeting a proposed definition of inadequate clinical outcome to osteoporosis therapy, recruited for the Observational Study of Severe Osteoporosis (OSSO).

DESIGN

Cross-sectional, observational study.

METHODS

Post-menopausal women with osteoporosis (n = 2314) were divided into Group 1 (those who had previously experienced a fragility fracture despite osteoporosis drug therapy for at least 12 months) (n = 1309, 57%), or Group 2 (those who had previously discontinued osteoporosis drug therapy due to non-compliance or side-effects) (n = 1005; 43%). Baseline clinical characteristics, quality of life (QOL) and osteoporosis/falls risk factors were analysed.

RESULTS

The overall population had low BMD (mean +/- SD T-score at lumbar spine -3.1 +/- 1.1), and risk factors for fracture such as previous fractures (67.8%), family history (15.1%), and prolonged glucocorticoid use (17.5%). QOL was poor: total QUALEFFO and EQ-5D scores were 46.8 +/- 18.7, and 0.50 +/- 0.33, respectively. Patients in Group 1 had higher age and body mass index, fewer hours of exercise, more previous fragility fractures and falls, and poorer QOL scores.

DISCUSSION

Our definition of inadequate clinical outcome from osteoporosis drug therapy identifies a severe osteoporosis cohort with poor QOL and increased fracture risk. Using such a definition may lead to earlier recognition of inadequate clinical outcome to osteoporosis therapy, and improved interventions and results.

Bone mass in Indian children--relationships to maternal nutritional status and diet during pregnancy: the Pune Maternal Nutrition Study

CONTEXT/OBJECTIVE

Bone mass is influenced by genetic and environmental factors. Recent studies have highlighted associations between maternal nutritional status during pregnancy and bone mass in the offspring. We hypothesized that maternal calcium intakes and circulating micronutrients during pregnancy are related to bone mass in Indian children. DESIGN/SETTING/PARTICIPANTS/MAIN OUTCOME MEASURES: Nutritional status was measured at 18 and 28 wk gestation in 797 pregnant rural Indian women. Measurements included anthropometry, dietary intakes (24-h recall and food frequency questionnaire), physical workload (questionnaire), and circulating micronutrients (red cell folate and plasma ferritin, vitamin B12, and vitamin C). Six years postnatally, total body and total spine bone mineral content and bone mineral density (BMD) were measured using dual-energy x-ray absorptiometry (DXA) in the children (n = 698 of 762 live births) and both parents.

RESULTS

Both parents' DXA measurements were positively correlated with the equivalent measurements in the children (P < 0.001 for all). The strength of these correlations was similar for fathers and mothers. Children of mothers who had a higher frequency of intake of calcium-rich foods during pregnancy (milk, milk products, pulses, non-vegetarian foods, green leafy vegetables, fruit) had higher total and spine bone mineral content and BMD, and children of mothers with higher folate status at 28 wk gestation had higher total and spine BMD, independent of parental size and DXA measurements.

CONCLUSIONS

Modifiable maternal nutritional factors may influence bone health in the offspring. Fathers play a role in determining their child's bone mass, possibly through genetic mechanisms or through shared environment.

Validation of a simple model for predicting liver fibrosis in HIV/hepatitis C virus-coinfected patients

OBJECTIVES

Recently, several models incorporating laboratory measurements have been validated for use as surrogate markers for liver fibrosis in hepatitis C virus (HCV) mono-infection, the simplest of these being the aspartate aminotransferase (AST) to platelet ratio index (APRI). We evaluated how well the APRI predicts significant hepatic fibrosis in patients with HIV/HCV coinfection.

METHODS

Forty-six HIV/HCV-coinfected patients who underwent liver biopsy and had concomitant laboratory measurements (+/-3 months) were included in the study. Significant fibrosis was defined as F2-F4 using Batt and Ludwig scoring (=3 Ishak). APRI=[(AST/upper limit of normal)/platelet count (10(9)/L)] x 100. We used sas proc logistic (SAS Institute, Cary, NC) to calculate the area under the receiver operating curve (ROC) (AUC). Sensitivities, specificities, positive predictive value (PPV) and negative predictive value (NPV) were compared using cut-offs previously identified in the literature.

RESULTS

Thirty-three of 46 patients (72%) had significant fibrosis on biopsy. For significant fibrosis, the area under the ROC for the APRI was 0.847+/-0.057. APRI scores >1.5 (the higher cut-off) were 100% specific and 52% sensitive; PPV was 100% and NPV 45%. Scores <0.5 (the lower cut-off) were 82% sensitive and 46% specific in ruling out significant fibrosis (PPV 79%; NPV 50%).

CONCLUSIONS

A simple model incorporating readily available laboratory data is highly predictive of significant fibrosis in HIV/HCV coinfection and could serve as a biopsy-sparing measure, thus making treatment more accessible for this population.

Personality analysis of patients complaining of sialorrhoea

BACKGROUND

Sialorrhoea, the symptom of apparent excessive secretion of saliva is a relatively uncommon complaint. Some authors consider that in the absence of clinical findings, then these patients have a psychiatric disorder masquerading as a physical illness. However, there is little evidence in the literature to support this conclusion and a detailed psychological assessment of this population has not previously been reported.

METHODS

In total, 18 patients and 18 age- and sex-matched controls were studied. All had a history of a complaint of excess salivation in the absence of any oral mucosal or systemic abnormality. All patients completed an Eysenck Personality Questionnaire.

RESULTS

There were no differences in the extroversion of psychoticism scores between the study and control group. However, the result showed significant increases in the neuroticism and Lie Scale score in the patient group.

CONCLUSIONS

The overall results of this study indicate that the complaint of sialorrhoea in otherwise healthy individuals does not have an organic basis and suggest that sialorrhoea is associated with high levels of neuroticism and a tendency to dissimulate.

Addressing the musculoskeletal components of fracture risk with calcium and vitamin D: a review of the evidence

Osteoporotic fractures are an extremely common and serious health problem in the elderly. This article presents the rationale for calcium and vitamin D supplementation in the prevention and treatment of osteoporotic fractures and reviews the literature evidence on the efficacy of this strategy. Two musculoskeletal risk factors are implicated in osteoporotic fractures in the elderly: the loss of bone mass due to secondary hyperparathyroidism and the increased propensity to falls. Calcium and vitamin D reverse secondary hyperparathyroidism with resultant beneficial effects on bone mineral density (BMD). Additionally, calcium and vitamin D supplementation significantly improves body sway and lower extremity strength, reducing the risk of falls. The effects of combined calcium and vitamin D on parathyroid function and BMD provide a strong rationale for the use of this therapy in the prevention and treatment of osteoporosis and osteoporotic fractures. There is general agreement that, in patients with documented osteoporosis, calcium and vitamin D supplementation should be an integral component of the management strategy, along with antiresorptive or anabolic treatment. Frail elderly individuals constitute another major target population for calcium and vitamin D because evidence from randomized studies in institutionalized elderly subjects demonstrates that these supplements reduce osteoporotic fracture risk, particularly in the presence of dietary deficiencies. However, the results of trials in community-dwelling subjects have been equivocal. Within the primary-care setting, further research is required to establish appropriate target subgroups for calcium and vitamin D supplementation; overall, the data are consistent with a benefit individuals with insufficient calcium and/or vitamin D, although patients with documented osteoporosis will derive further benefit in terms of fracture prevention from the addition of an antiresorptive agent.

Angiotensin II type I receptor gene polymorphism: anthropometric and metabolic syndrome traits

BACKGROUND

The renin angiotensin system is important in the regulation of vascular tone and fluid and electrolyte balance. The angiotensin converting enzyme gene (ACE) genotype has been shown to affect exercise response and glucose load response dependent on birth weight. Angiotensin II type I receptor (AGTR1) A1166C has previously been associated with the development of hypertension and coronary disease, but its metabolic effects have not been investigated.

METHOD

AGTR1 A1166C was genotyped by allele specific PCR in 378 individuals from Hertfordshire, UK, who had been characterised for metabolic syndrome traits.

RESULTS

Genotype counts were: AA, 183; AC, 170; CC, 25, consistent with Hardy-Weinberg equilibrium. The CC genotype was associated with significantly lower body mass index (by 1.7 units) in men (p = 0.03), and the same magnitude effect in women with significant lower weight in both genders (p = 0.01), also lower waist circumference and waist-hip ratio (p = 0.01) in men, with a trend for lower waist circumference in women also. Additionally, the CC genotype and/or C allele was associated with lower fasting glucose and insulin, and 30 and 120 min glucose in men (respectively, p = 0.08, 0.04, 0.01, 0.06). Lower means of systolic blood pressure, pulse pressure, cholesterol, and fasting triglyceride were also observed for the CC genotype in both genders though these were not statistically significant.

CONCLUSIONS

The AGTR1 1166 CC genotype appears to predispose to favourable anthropometric and metabolic traits, relative to cardiovascular risk.

Beyond daily dosing: clinical experience

Osteoporosis has had a significant public health impact, with many sufferers experiencing fractures. Such fractures lead to increased disability, mortality and reduced quality of life, all of which raise healthcare costs. Oral bisphosphonates are associated with significant antifracture efficacy and have therefore become the mainstay of treatment for postmenopausal osteoporosis. Poor therapeutic adherence with daily bisphosphonates has been improved by the introduction of weekly regimens, although adherence levels remain suboptimal. Bisphosphonate regimens with dosing intervals beyond a week have therefore been developed to address this issue. Oral ibandronate, a potent nitrogen-containing bisphosphonate, has been studied using daily and intermittent regimens (between-dose interval >2 months). The initial phase II 2-year study confirmed the feasibility of the intermittent regimen, providing increases in lumbar spine bone mineral density (BMD) superior to placebo (P < 0.01) and equivalent to the daily regimen (5.64% vs. 5.54%, respectively). BONE (Oral iBandronate Osteoporosis vertebral fracture trial in North America and Europe), a large phase III 3-year study was subsequently initiated, including 2946 women with postmenopausal osteoporosis and testing both a daily as well as an intermittent regimen with a dose-free interval of more than 2 months. Significant vertebral antifracture efficacy (the primary study endpoint) was demonstrated with daily (2.5 mg) and intermittent (20 mg every other day for 12 doses every 3 months) ibandronate in comparison with placebo (P < or = 0.0006). As a result of the study not being designed and powered to show an effect on non-vertebral fractures and the overall population being at low risk for osteoporotic fractures, differences in the incidence of non-vertebral fractures were similar between groups (8.2-9.1%) However, a post hoc analysis in a subgroup of patients with a femoral neck BMD T-score < -3.0 showed that daily ibandronate significantly reduced the risk of non-vertebral fractures (P = 0.012). Both regimens were associated with significant increases in lumbar spine and proximal femur BMD and normalization of bone turnover. As determined by adverse event incidence and laboratory evaluation, the safety profile for both ibandronate regimens was similar to that observed for placebo. The BONE study therefore confirmed that daily or intermittent ibandronate is an effective and well-tolerated treatment for postmenopausal women. Being the first study to demonstrate antifracture efficacy with an intermittent regimen, it provided "proof of concept" for beyond weekly dosing with ibandronate and prompted further development of a more convenient once-monthly regimen.

Early environmental factors and rheumatoid arthritis

The precise cause of autoimmune diseases such as rheumatoid arthritis (RA) remains uncertain. In recent years there has been extensive investment in pursuing genes important in RA. However, estimates suggest that the risk of developing RA is at most 50% determined by genes. There has been limited success defining the environmental factors important in developing RA. We hypothesize that this lack of success may be due to a concentration on the time around disease onset. There is evidence of production of the autoantibodies rheumatoid factor (RF) and anti-cyclic citrullinated peptides (anti-CCP) and increased levels of C-reactive protein (CRP) years before RA becomes clinically apparent. In addition, early life events including intrauterine growth retardation (IUGR) may have long lasting effects on immune function. We review the evidence that the early environment through effects on growth and infectious exposure may influence the likelihood of developing autoimmune diseases such as RA.

Economic evaluation of parathyroid hormone (PTH) in the treatment of osteoporosis in postmenopausal women

Parathyroid hormone (PTH) is a new treatment for osteoporosis and has been shown to reduce the risks of vertebral and non-vertebral fractures in postmenopausal women in clinical trials. The objective of this study was to estimate the cost-effectiveness of teriparatide in addition to calcium and vitamin D, using a simulation model. The base case analysis was conducted for a cohort of 69-year-old women in Sweden who had at least one previous vertebral fracture and low bone mineral density. The model simulated the course of events in 6-month cycles in individual patients until death or 100 years of age. During each cycle the patients were at risk of experiencing clinical vertebral, hip or wrist fractures, or death. Total accumulated life-time costs and quality-adjusted life years (QALYs) were estimated. Swedish data on fracture costs, utility reductions after fracture, fracture risks and mortality rates were used. The model incorporated new epidemiological evidence that indicates fracture risks and mortality rates are higher in the subsequent years post-fracture. The results showed that the cost-effectiveness of the treatment is highly dependant on the risk profile of the treated patients and the timing of starting treatment relative to previous fractures. The cost per QALY gained for treatment of a population of 69-year-olds with a T-score at the femoral neck of -3 was in the base case estimated to be between EUR (euro) 20,000 and 64,000 for patients with a recent or historic vertebral fracture respectively. The study provides further evidence of the benefit and cost-effectiveness of starting osteoporotic treatments early in patients with a new fracture, and also that teriparatide may provide valuable clinical benefits for these patients and may be considered a cost-effective intervention when targeted to the appropriate patients.

Maternal vitamin D status during pregnancy and childhood bone mass at age 9 years: a longitudinal study

BACKGROUND

Vitamin D insufficiency is common in women of childbearing age and increasing evidence suggests that the risk of osteoporotic fracture in adulthood could be determined partly by environmental factors during intrauterine and early postnatal life. We investigated the effect of maternal vitamin D status during pregnancy on childhood skeletal growth.

METHODS

In a longitudinal study, we studied 198 children born in 1991-92 in a hospital in Southampton, UK; the body build, nutrition, and vitamin D status of their mothers had been characterised during pregnancy. The children were followed up at age 9 years to relate these maternal characteristics to their body size and bone mass.

FINDINGS

49 (31%) mothers had insufficient and 28 (18%) had deficient circulating concentrations of 25(OH)-vitamin D during late pregnancy. Reduced concentration of 25(OH)-vitamin D in mothers during late pregnancy was associated with reduced whole-body (r=0.21, p=0.0088) and lumbar-spine (r=0.17, p=0.03) bone-mineral content in children at age 9 years. Both the estimated exposure to ultraviolet B radiation during late pregnancy and the maternal use of vitamin D supplements predicted maternal 25(OH)-vitamin D concentration (p<0.0001 and p=0.0110, respectively) and childhood bone mass (p=0.0267). Reduced concentration of umbilical-venous calcium also predicted reduced childhood bone mass (p=0.0286).

INTERPRETATION

Maternal vitamin D insufficiency is common during pregnancy and is associated with reduced bone-mineral accrual in the offspring during childhood; this association is mediated partly through the concentration of umbilical venous calcium. Vitamin D supplementation of pregnant women, especially during winter months, could lead to longlasting reductions in the risk of osteoporotic fracture in their offspring.