S D'Angelo

The role of mental health problems and common psychotropic drug treatments in accidental injury at work: a case-control study.

Objectives Mental illness and psychotropic drugs have been linked with workplace injury, but few studies have measured exposures and outcomes independently or established their relative timings. To address this shortcoming, we conducted a case–control study nested within a database prospectively recording injury consultations, diagnoses and drug prescriptions. Methods The Clinical Practice Research Datalink logs primary care data for 6% of the British population, coding all consultations (by the Read system) and drug prescriptions. We identified 1348 patients aged 16–64 years from this database who had consulted a family doctor or hospital over a 20-year period for workplace injury (cases, 479 diagnostic codes) and 6652 age, sex and practice-matched controls with no such consultation. Groups were compared in terms of consultations for mental health problems (1328 codes) and prescription of psychotropic drugs prior to the cases injury consultation using conditional logistic regression. Results In total, 1846 (23%) subjects had at least one psychiatric consultation before the index date and 1682 (21%) had been prescribed a psychotropic drug. The OR for prior mental health consultation was 1.44 (p<0.001) and that for psychotropic drug treatment was 1.57 (p<0.001). Risks were significantly elevated for several subclasses of mental health diagnosis (eg, psychosis, neurosis) and for each of the drug classes analysed. Assuming causal relationships, about 9–10% of all workplace injuries leading to medical consultation were attributable to mental illness or psychotropic medication. Conclusions Mental health problems and psychotropic treatments may account for an important minority of workplace injuries.

Dupuytren's contracture and occupational exposure to hand-transmitted vibration

Aims The relation between Dupuytrens contracture and occupational exposure to hand-transmitted vibration (HTV) has frequently been debated. We explored associations in a representative national sample of workers with well-characterised exposure to HTV. Methods We mailed a questionnaire to 21 201 subjects aged 16–64 years, selected at random from the age-sex registers of 34 general practices in Great Britain and to 993 subjects chosen randomly from military pay records, asking about occupational exposure to 39 sources of HTV and about fixed flexion contracture of the little or ring finger. Analysis was restricted to men at work in the previous week. Estimates were made of average daily vibration dose (A(8) root mean squared velocity (rms)) over that week. Associations with Dupuytrens contracture were estimated by Poisson regression, for lifetime exposure to HTV and for exposures in the past week >A(8) of 2.8 ms−2 rms. Estimates of relative risk (prevalence ratio (PR)) were adjusted for age, smoking status, social class and certain manual activities at work. Results In all 4969 eligible male respondents supplied full information on the study variables. These included 72 men with Dupuytrens contracture, 2287 with occupational exposure to HTV and 409 with A(8)>2.8 ms−2 in the past week. PRs for occupational exposure to HTV were elevated 1.5-fold. For men with an A(8)>2.8 ms−2 in the past week, the adjusted PR was 2.85 (95% CI 1.37 to 5.97). Conclusions Our findings suggest that risk of Dupuytrens contracture is more than doubled in men with high levels of weekly exposure to HTV.

Response to antenatal cholecalciferol supplementation is associated with common vitamin D related genetic variants.

Context: Single-nucleotide polymorphisms (SNPs) in genes related to vitamin D metabolism have been associated with serum 25-hydroxyvitamin D [25(OH)D] concentration, but these relationships have not been examined following antenatal cholecalciferol supplementation. Objective: To determine whether SNPs in DHCR7, CYP2R1, CYP24A1, and GC are associated with the response to gestational cholecalciferol supplementation. Design: Within-randomization group analysis of the Maternal Vitamin D Osteoporosis Study trial of antenatal cholecalciferol supplementation. Setting: Hospital antenatal clinics. Participants: In total, 682 women of white ethnicity (351 placebo, 331 cholecalciferol) were included. SNPs at rs12785878 (DHCR7), rs10741657 (CYP2R1), rs6013897 (CYP24A1), and rs2282679 (GC) were genotyped. Interventions: 1000 IU/d cholecalciferol from 14 weeks of gestation until delivery. Main Outcome Measure: 25(OH)D at randomization and 34 weeks of gestation were measured in a single batch (Liaison; Diasorin, Dartford, UK). Associations between 25(OH)D and the SNPs were assessed by linear regression using an additive model [β represents the change in 25(OH)D per additional common allele]. Results: Only rs12785878 (DHCR7) was associated with baseline 25(OH)D [β = 3.1 nmol/L; 95% confidence interval (CI), 1.0 to 5.2 nmol/L; P < 0.004]. In contrast, rs10741657 (CYP2R1) (β = −5.2 nmol/L; 95% CI, −8.2 to −2.2 nmol/L; P = 0.001) and rs2282679 (GC) (β = 4.2 nmol/L; 95% CI, 0.9 to 7.5 nmol/L; P = 0.01) were associated with achieved 25(OH)D status following supplementation, whereas rs12785878 and rs6013897 (CYP24A1) were not. Conclusions: Genetic variation in DHCR7, which encodes 7-dehyrocholesterol reductase in the epidermal vitamin D biosynthesis pathway, appears to modify baseline 25(OH)D. In contrast, the response to antenatal cholecalciferol supplementation was associated with SNPs in CYP2R1, which may alter 25-hydroxylase activity, and GC, which may affect vitamin D binding protein synthesis or metabolite affinity.

Site-Dependent Reference Point Microindentation Complements Clinical Measures for Improved Fracture Risk Assessment at the Human Femoral Neck.

In contrast to traditional approaches to fracture risk assessment using clinical risk factors and bone mineral density (BMD), a new technique, reference point microindentation (RPI), permits direct assessment of bone quality; in vivo tibial RPI measurements appear to discriminate patients with a fragility fracture from controls. However, it is unclear how this relates to the site of the most clinically devastating fracture, the femoral neck, and whether RPI provides information complementary to that from existing assessments. Femoral neck samples were collected at surgery after low-trauma hip fracture (n = 46; 17 male; aged 83 [interquartile range 77-87] years) and compared, using RPI (Biodent Hfc), with 16 cadaveric control samples, free from bone disease (7 male; aged 65 [IQR 61-74] years). A subset of fracture patients returned for dual-energy X-ray absorptiometry (DXA) assessment (Hologic Discovery) and, for the controls, a micro-computed tomography setup (HMX, Nikon) was used to replicate DXA scans. The indentation depth was greater in femoral neck samples from osteoporotic fracture patients than controls (p < 0.001), which persisted with adjustment for age, sex, body mass index (BMI), and height (p < 0.001) but was site-dependent, being less pronounced in the inferomedial region. RPI demonstrated good discrimination between fracture and controls using receiver-operating characteristic (ROC) analyses (area under the curve [AUC] = 0.79 to 0.89), and a model combining RPI to clinical risk factors or BMD performed better than the individual components (AUC = 0.88 to 0.99). In conclusion, RPI at the femoral neck discriminated fracture cases from controls independent of BMD and traditional risk factors but dependent on location. The clinical RPI device may, therefore, supplement risk assessment and requires testing in prospective cohorts and comparison between the clinically accessible tibia and the femoral neck.

Epilepsy, diabetes mellitus and accidental injury at work

AIMS To assess the contribution of epilepsy and diabetes to occupational injury. METHODS The Clinical Practice Research Datalink logs primary care data for 6% of the British population, coding all consultations and treatments. Using this, we conducted a population-based case-control study, identifying patients aged 16-64 years, who had consulted over two decades for workplace injury, plus matched controls. By conditional logistic regression, we assessed risks for diabetes and epilepsy overall, several diabetic complications and indices of poor control, occurrence of status epilepticus and treatment with hypoglycaemic and anti-epileptic agents. RESULTS We identified 1348 injury cases and 6652 matched controls. A total of 160 subjects (2%) had previous epilepsy, including 29 injury cases, whereas 199 (2.5%) had diabetes, including 77 with eye involvement and 52 with a record of poor control. Odds ratios (ORs) for occupational injury were close to unity, both in those with epilepsy (1.07) and diabetes (0.98) and in those prescribed anti-epileptic or hypoglycaemic treatments in the previous year (0.87-1.16). We found no evidence of any injury arising directly from a seizure and no one had consulted about their epilepsy within 100 days before their injury consultation. Two cases and six controls had suffered status epilepticus (OR versus never had epilepsy 1.61). Risks were somewhat higher for certain diabetic complications (OR 1.44), although lower among those with eye involvement (OR 0.70) or poor diabetic control (OR 0.50). No associations were statistically significant. CONCLUSIONS No evidence was found that diabetes or epilepsy are important contributors to workplace injury in Britain.

Heavy manual work throughout the working lifetime and muscle strength among men at retirement age

Introduction Reductions in heavy manual work as a consequence of mechanisation might adversely impact muscle strength at older ages. We investigated the association between grip strength at retirement age and lifetime occupational exposure to physically demanding activities. Grip strength is an important predictor of long-term health and physical function in older people. Methods Grip strength (maximum of three readings in each hand) was measured in men from the Hertfordshire Cohort Study at a single examination when their mean age was 65.8 (SD 2.9) years. Associations with lifetime occupational exposure (ascertained by questionnaire) to three activities (standing/walking ≥4 h/day; lifting ≥25 kg; and energetic work sufficient to induce sweating) were assessed by multivariable linear regression with adjustment for various potential confounders. Results Complete data were available from 1418 men who had worked for at least 20 years. After adjustment for age, height and weight, those with longer exposures to walking/standing and heavy lifting had lower grip strength, but the relationship disappeared after further adjustment for confounders. Working at physical intensity sufficient to induce sweating was not significantly associated with grip strength. Conclusions We found no evidence that physically demanding occupational activities increase hand grip strength at normal retirement age. Any advantages of regular physical occupational activity may have been obscured by unmeasured socioeconomic confounders.

Sleep disturbance and the older worker: findings from the Health and Employment after Fifty study

Objectives The aim of this study was to characterize the descriptive epidemiology of insomnia in midlife and explore the relative importance of different occupational risk factors for insomnia among older workers. Methods A questionnaire was mailed to all adults aged 50-64 years registered with 24 English general practices. Insomnia was defined as having at least one of four problems with sleep severely in the past three months. Subjects were also asked about employment conditions, feelings concerning work, and their health. Associations were assessed by logistic regression and population attributable fractions (PAF) calculated. Results Analysis was based on 8067 respondents (5470 in paid work), 18.8% of whom reported insomnia. It was more common among women, smokers, obese individuals, those living alone, and those in financial hardship, and less prevalent among the educated, those in South-East England, and those with friendships and leisure-time pursuits. Occupational risk factors included unemployment, shift working, lack of control and support at work, job insecurity, job dissatisfaction and several of its determinants (lacking a sense of achievement, feeling unappreciated, having difficult work colleagues, feeling unfairly criticized). Population burden of insomnia was associated more strongly with difficulties in coping with work demands, job insecurity, difficult colleagues, and lack of friendships at work [population attributable fraction (PAF) 15-33%] than shift work and lack of autonomy or support (PAF 5-7%). It was strongly associated with seven measures of poorer self-assessed health. Conclusions Employment policies aimed at tackling insomnia among older workers may benefit from focusing particularly on job-person fit, job security and relationships in the workplace.

Exposure to heavy physical occupational activities during working life and bone mineral density at the hip at retirement age

Background People in sedentary occupations are at increased risk of hip fracture. Hip fracture is significantly associated with low bone mineral density (BMD) measured at the hip. Physical activity is important in the development and maintenance of BMD, but the effects of occupational physical activity on bone health are unclear. We investigated the influence of lifetime physical activity on BMD at the hip. Methods This was a cross-sectional epidemiological study of the associations between total hip BMD measured by dual-energy X-ray absorptiometry at retirement age and lifetime exposure to occupational physical workload (standing/walking ≥4 h/day; lifting ≥25 kg; energetic work sufficient to induce sweating and manual work). Results Complete data on occupational exposures were available for 860 adults (488 men and 372 women) who had worked ≥20 years. Their mean age was 65 years, and many reported heavy physical workplace activities over prolonged durations. There were no statistically significant associations between total hip BMD and any of these measures of lifetime occupational physical activity in men or women. Conclusions Lifetime cumulative occupational activity was not associated with hip BMD at retirement age. Our findings suggest that, if sedentary work conveys an increased risk of hip fracture, it is unlikely that the mechanism is through reductions in BMD at the hip and may relate to other physical effects, such as falls risk. Further studies will be needed to test this hypothesis.

Calcium and vitamin D supplementation are not associated with risk of incident ischaemic cardiac events or death: findings from the UK Biobank cohort

We investigated associations between calcium/vitamin D supplementation and incident cardiovascular events/deaths in a UK population‐based cohort. UK Biobank is a large prospective cohort comprising 502,637 men and women aged 40 to 69 years at recruitment. Supplementation with calcium/vitamin D was self‐reported, and information on incident hospital admission (ICD‐10) for ischemic heart disease (IHD), myocardial infarction (MI), and subsequent death was obtained from linkage to national registers. Cox proportional hazards models were used to investigate longitudinal relationships between calcium/vitamin D supplementation and hospital admission for men/women, controlling for covariates. A total of 475,255 participants (median age 58 years, 55.8% women) had complete data on calcium/vitamin D supplementation. Of that number, 33,437 participants reported taking calcium supplements; 19,089 vitamin D; and 10,007 both. In crude and adjusted analyses, there were no associations between use of calcium supplements and risk of incident hospital admission with either IHD, or subsequent death. Thus, for example, in unadjusted models, the hazard ratio (HR) for admission with myocardial infarction was 0.97 (95% confidence interval [CI] 0.79–1.20, p = 0.79) among women taking calcium supplementation. Corresponding HR for men is 1.16 (95% CI 0.92–1.46, p = 0.22). After full adjustment, HR (95% CI) were 0.82 (0.62–1.07), p = 0.14 among women and 1.12 (0.85–1.48), p = 0.41 among men. Adjusted HR (95% CI) for admission with IHD were 1.05 (0.92–1.19), p = 0.50 among women and 0.97 (0.82–1.15), p = 0.77 among men. Results were similar for vitamin D and combination supplementation. There were no associations with death, and in women, further adjustment for hormone‐replacement therapy use did not alter the associations. In this very large prospective cohort, there was no evidence that use of calcium/vitamin D supplementation was associated with increased risk of hospital admission or death after ischemic cardiovascular events.

Assessment of bone mineral content and fracture risk: a UK prospective cohort study

Abstract Background Poor early growth is associated with reduced adult bone mineral content (BMC), but not bone mineral density (BMD). Although low BMD is a well-established risk factor for future fracture, little is known about the performance characteristics of BMC in fracture prediction. We therefore investigated the predictive value of bone area, BMC, and BMD for incident fracture in a prospective cohort of UK women. Methods Women aged 20–80 years, recruited from four general practices in Southampton, underwent assessment by dual energy X-ray absorptiometry between 1991 and 1993. All women were then contacted in 1998–99 with a validated postal questionnaire to collect information on incident fractures and potential confounding factors including medication use. All fractures were confirmed by assessment of images and radiology reports by a research nurse. Cox proportional hazards models were used to explore the risk of incident fracture and results expressed as gradient of risk (GR) and 95% CI. Associations were adjusted for age, body-mass index, alcohol consumption, smoking, hormone replacement therapy, medications, and history of fracture. This study was approved by the Southampton Joint Ethics Committee. Findings 674 women were recruited and 443 responded to the questionnaire. 55 women (12%) reported a fracture. In fully adjusted models, femoral neck BMC and BMD were similarly predictive of incident fracture (GR 1·64, 95% CI 1·19–2·26 [p=0·002] and 1·76, 1·19–2·60 [p=0·005], respectively). By contrast, femoral neck bone area was not associated with incident fracture (1·15, 0·88–1·50; p=0.32). Similar results were found with bone indices at the lumbar spine and whole body. Interpretation BMC and BMD seem to predict incident fracture with similar gradients of risk, even after adjustment for body size. These findings suggest that factors in early life that are associated with total skeletal mineralisation are likely to have implications for adult fracture risk. Funding Medical Research Council; British Heart Foundation; Arthritis Research UK; National Osteoporosis Society; International Osteoporosis Foundation; National Institute for Health Research (NIHR) Southampton Biomedical Research Centre, University of Southampton and University Hospital Southampton NHS Foundation Trust; NIHR Musculoskeletal Biomedical Research Unit, University of Oxford.