Foot ulceration and its association with mortality in diabetes mellitus: a meta-analysis

BACKGROUND

Diabetic foot ulcers portend an almost twofold increase in all-cause mortality compared with diabetes on its own.

AIM

To investigate the association between diabetic foot ulcers and risk of death.

METHODS

We performed a meta-analysis of all observational studies investigating the association between diabetic foot ulcers and all-cause mortality. Risk ratios and risk differences were pooled in a random-effects model. The I² statistic was used to quantify heterogeneity between studies.

RESULTS

Altogether, we identified 11 studies that reported 84 131 deaths from any cause in 446 916 participants with diabetes during a total of 643 499 person-years of follow-up. The crude event rate for all-cause mortality in individuals with diabetes who did not develop foot ulceration was 22% lower at 181.5 deaths (per 1000 person-years) than in those who developed foot ulcers (230.8 per 1000 person-years). Diabetic foot ulceration was associated with an increased risk of all-cause mortality (pooled relative risk 2.45, 95% CI 1.85-2.85). We did not observe any tangible differences in risk of all-cause mortality from diagnosis in studies reporting a mean duration of follow-up of ≤3 years (relative risk 2.43, 95% CI 2.27-2.61) or >3 years (relative risk 2.26, 95% CI 2.13-2.40) years. Funnel plot inspection revealed no significant publication bias among studies included in this meta-analysis.

CONCLUSIONS

Our study shows an excess rate of all-cause mortality in people with diabetic foot ulceration when compared to those without foot ulceration. It is imperative that early interventions to prevent foot ulceration and modify cardiovascular disease risk factors are put in place to reduce excess mortality.

Developing a foot ulcer risk model: what is needed to do this in a real-world primary care setting?

AIM

To determine how routinely collected data can inform a risk model to predict de novo foot ulcer presentation in the primary care setting.

METHODS

Data were available on 15 727 individuals without foot ulcers and 1125 individuals with new foot ulcers over a 12-year follow-up in UK primary care. We examined known risk factors and added putative risk factors in our logistic model.

RESULTS

People with foot ulcers were 4.2 years older (95% CI 3.1-5.2) than those without, and had higher HbA_1c % (mean 7.9 ± 1.9 vs 7.5 ± 1.7) / HbA_1c mmol/mol (63 ± 21 vs 59 ± 19) (p<0.0001) concentration [+0.45 (95% CI 0.33-0.56), creatinine level [+6.9 μmol/L (95% CI 4.1-9.8)] and Townsend score [+0.055 (95% CI 0.033-0.077)]. Absence of monofilament sensation was more common in people with foot ulcers (28% vs 21%; P<0.0001), as was absence of foot pulses (6.4% vs 4.8%; P=0.017). There was no difference between people with or without foot ulcers in smoking status, gender, history of stroke or foot deformity, although foot deformity was extremely rare (0.4% in people with foot ulcers, 0.6% in people without foot ulcers). Combining risk factors in a single logistic regression model gave modest predictive power, with an area under the receiver-operating characteristic curve of 0.65 (95% CI 0.62-0.67). The prevalence of ulceration in the bottom decile of risk was 1.8% and in the top decile it was 13.4% (compared with an overall prevalence of 6.5%); thus, the presence of all six risk factors gave a relative risk of 7.4 for development of a foot ulcer over 12 years.

CONCLUSION

We have made some progress towards defining a variable set that can be used to create a foot ulcer prediction model. More accurate determination of foot deformity/pedal circulation in primary care may improve the predictive value of such a future risk model, as will identification of additional risk variables.

Success Rates in a Diabetes Specialist Nurse-Led Education Programme: Re-setting the Glucostat

Analysis of National Diabetes Audit data from 2011-2012 of newly diagnosed people with type 1 diabetes mellitus (DM) found low initial success rates in much of the UK at 20% on initial training, while an unusually high success rate of 75% achieving target HbA1C<58 mmol/mol (< 7.5%) was found in Cheshire (England average=40.8%). We present a review of the approach taken by the Cheshire Diabetes team in the 12 months following diagnosis. Between 2012 and 2013, 15 consecutive newly diagnosed people with type 1 DM were followed up for 18 months. All received support and advice by community Diabetes Specialist Nurses (DSNs) and Dieticians covering Central and Eastern Cheshire, UK. Mean±SD age at diagnosis was 23±3 years. The period of contact with the DSN service varied from 7-12 weeks. Baseline HbA1C of 99 mmol/mol [11.2%] (95% CI: 86-111 mmol/mol [10.0-12.3%]) declined by ~50% to 49 mmol/mol [6.6%] (41-57 mmol/mol [5.9-7.4%]; F=16.9, p<0.001) at 6 months and did not change between 6-12 months. Of those newly diagnosed with type 1 DM, 84.6% achieved a target HbA1C<58 mmol/mol (<7.5%) and 61.5% met a target<48 mmol/mol (<6.5%). There was no significant weight change during the study. The key elements of this bio-psycho-social approach by the DSN team included providing psychological support, patient engagement, demonstrating positive regard, gaining trust, identifying health-seeking behaviour, providing key decision-making skills and developing a self-management plan. This resulted in improvements in overall glycaemic control well above the national average without untoward weight gain. The UK National Diabetes Audit (2011-2012) in newly diagnosed type 1 diabetics in Cheshire, UK, showed a success rate at 6 months post-diagnosis of 75% achieving a target HbA1C<58 mmol/mol (<7.5%) compared with the national average of 40.8%. Initially thought to be erroneous, these excellent results were confirmed. The approach taken to achieve them is herein described.

Socioeconomic deprivation independently predicts painful diabetic neuropathy in type 2 diabetes

OBJECTIVE

Painful peripheral neuropathy in people with type 2 diabetes is a disabling complication. We explored associations of this condition with socioeconomic deprivation.

RESEARCH DESIGN AND METHODS

The Townsend index of socioeconomic deprivation was examined in the pseudonymised GP records of 15388 (44.1% female) individuals with type 2 diabetes in the Cheshire county of England, and related to prevalence of drug treated painful diabetic neuropathy. We also analysed prescription trends with respect to pharmacotherapy for neuropathy pain relief.

RESULTS

Treatment for neuropathic pain was initiated in 3 266 (21.2%) of patients. Those on treatment were older [68.2 (95% CI 67.8-68.7) vs. 66.6 (66.4-66.8) years] than those not on treatment. There was no difference in HbA1c (7%, 55 mmol/mol).There were significant differences between the groups for the Townsend deprivation index, with a greater proportion (30.6% vs. 22.8% of patients with treated neuropathic pain) having a score of ≥1 (Χ(2)=83.9, p<0.0001).Multivariate logistic regression analyses indicated that each unit increment in the Townsend index was associated with an 6% increased odds of requiring neuropathic pain treatment [odds ratio (95%CI) 1.06 (1.05-1.08), p<0.0001] independent of 5 year age band, BMI, gender, systolic BP, eGFR, HbA1C and total cholesterol.

CONCLUSIONS

In this study using pseudonymised clinical records, a higher level of socioeconomic deprivation seemingly may predispose to severe neuropathic pain in diabetes requiring pharmacological intervention. Targeted allocation of healthcare resources to this group may offer clinical benefits.

Measuring vitamin D levels: surrogates are insufficient

AIMS

With the increasing evidence of adverse consequences because of low vitamin D levels on health demand for vitamin D, screening is increasing. The objective of the study was to assess whether parathyroid hormone (PTH) levels/bone profile is sufficient to identify patients with vitamin D insufficiency or deficiency, or whether vitamin D should be measured directly.

METHODOLOGY

A total of 1560 serum specimens, with requests for 25-hydroxyvitamin D (25-OH vitamin D), calcium, phosphate, alkaline phosphatase (ALP), creatinine and PTH on the same sample were analysed at Salford Royal Hospital from November 2010 to November 2012.

RESULTS

The prevalence of total vitamin D insufficiency or deficiency (defined as total 25-OH vitamin D < 50 nmol/l) was 62.9% (981/1560) overall, with males having higher proportions (67.2 vs. 59.3 per cent; χ(2) = 8.78, p = 0.003). There was no overall trend in mean serum adjusted calcium across categories of 25-OH vitamin D status but mean serum phosphate was significantly lower (F = 6.53, p < 0.0001) in patients with a 25-OH vitamin D level < 50 nmol/l. However in patients with vitamin D deficiency, a significant proportion had PTH, calcium, phosphate and alkaline phosphatase levels within the laboratory normal range. Even at a 25-OH vitamin D < 10 nmol/l, 71.6% had a normal PTH, 89.8% had normal serum calcium levels, 84.9% had normal phosphate levels and 81.6% had normal serum ALP.

CONCLUSIONS

Therefore, despite the costs associated with the measurement of vitamin D, our findings show that no surrogate is adequate for screening for vitamin D deficiency.

Haemostatic factors, lipoproteins and long-term mortality in a multi-ethnic population of Gujarati, African-Caribbean and European origin

OBJECTIVES

To examine the relations between haemostatic factors and lipoproteins with mortality in British Europeans, African-Caribbeans (AfC) and Gujarati Indians.

METHODS

A prospective cohort study of 331 subjects (40-79 years), followed-up over 26 years for mortality. Apolipoprotein-A1 (Apo-A1), apolipoprotein-B (Apo-B), factor VII coagulant activity (FVIIc), fibrinogen and von Willebrand Factor (vWF) were measured at baseline in 118 Europeans, 100 AfC and 113 Gujaratis. Aortic pulse wave velocity (aPWV) was measured in 174 participants.

RESULTS

147 (44.4%) subjects died during a median of 24 years follow-up with 69 cardiovascular deaths. Women at baseline had higher, and AfC males the lowest FVIIc and Apo-A1 levels. Baseline age-sex and ethnicity adjusted FVIIc levels were higher in those who died (131.0 vs. 117.4%; P = 0.048). In similarly adjusted partial correlations, Apo-A1 was inversely related to arterial stiffness (ρ = -0.23, P = 0.04). Over the 26 years follow-up, participants below the median (i.e. with lower concentration) of FVIIc, Fibrinogen, Apo-B and vWF had better survival rates than those with higher concentrations; those with higher concentrations of Apo-A1 had better survival. In Cox multivariable regression analyses including sex, ethnicity and aPWV, independently increased risk of all-cause mortality came only from SBP (per 5 mmHg); P = 0.011), age (per year); P < 0.0001 and FVIIc at 7% (per 10-unit; HR 1.07 (1.02, 1.12); P = 0.008. Separately, Apo-A1 (HR 0.12 (0.02, 0.75; P = 0.029) was independently associated with a very significant 88% reduction in all-cause mortality.

CONCLUSIONS

Despite a relatively small sample size, long-term follow-up suggests an independent effect of the prothrombotic state (via FVIIc) and apo-A1 (a constituent of HDL) on mortality.

HOMA-S is associated with greater HbA1c reduction with a GLP-1 analogue in patients with type 2 diabetes

Exenatide, a glucagon-like peptide-1 (GLP-1) analogue, is an effective glucoregulator for treating overweight individuals, not at target HbA1 c. This prospective study aimed to determine whether estimates of beta cell function (HOMA-B) and insulin sensitivity (HOMA-S) predict response to Exenatide treatment.Prospective data on 43 type 2 diabetes patients were collected for up to 2.8 years in UK primary care. HOMA-B and HOMA-S were estimated prior to initiating Exenatide, with monitoring of cardio-metabolic risk factors.Mean (SD) age and BMI pre-treatment were 54.1±10.5 years and 35.7±7.5 kg/m2 respectively. HbA1c decreased (mean reduction 0.9%, p=0.04; p for trend=0.01) in 61% of patients. In univariate analyses, HOMA-S as a measure of insulin sensitivity was inversely (β=- 0.41, p 0.009) related to change in HbA1c, with no relation for HOMA-B.In a random effects regression model that included age at baseline, weight, LDL-C, HDL-C and triglycerides, change in HbA1c (β= - 0.14, p<0.001) and HDL-C (β= - 0.52, p=0.011) were independently associated with increasing insulin sensitivity (r2=0.52). Thus patients with greater measured insulin sensitivity achieved greater reduction in HbA1c independent of the factors described above.In logistic regression those in the highest tertile of log-HOMA-S were 45% more likely to have a fall in HbA1c with an odds ratio (OR) of 0.55 (95% CI 0.47-0.66) p<0.0001 (log likelihood ratio for the model χ2=71.6, p<0.0001).Patients with greater measured insulin sensitivity achieve greater reduction in HbA1c with Exenatide. Determination of insulin sensitivity may assist in guiding outcome expectation in overweight patients treated with GLP-1 analogues.

Quantitative adjustment for macroprolactin is an integral part of laboratory assessment of hyperprolactinaemia

INTRODUCTION

Prolactin circulates predominantly as a 23-kDa monomer, and a high-molecular-weight form largely consisting of a complex of prolactin and an anti-prolactin IgG autoantibody, called macroprolactin. This cross-reacts with conventional laboratory assays for prolactin. We here describe how quantitative adjustment for this may assist patient management.In a consecutive series of 218 patients with prolactin elevated to 400 mu/L or more in men (normal range ≤ 180) (n=79, 36.2% of sample) and 1 000 mu/L or more in women (normal range ≤ 500) (n=139, 63.8%) a macroprolactin screen was performed using PEG precipitation.

RESULTS

Where present, median macroprolactin as a proportion of total prolactin was in women 13% (percentile 25-percentile 75: 7-25%) and in men 15% (7-30%).The distribution of macroprolactin as a proportion of total prolactin was markedly skewed to the left with 69.7% of women and 62.9% of men having macroprolactin proportion of 20% or less. There was no relation between %macroprolactin and total measured prolactin, age or gender.Of relevance to clinical management, in 24% of men and 20.5% of women, correction for estimated macroprolactin gave an adjusted monomeric prolactin level below the agreed threshold for further investigation, potentially avoiding unnecessarily referral.In our clinical series, quotation of an adjusted monomeric prolactin would have resulted in unnecessary further investigation being avoided in a number of cases.

DISCUSSION

Screening for macroprolactin is a key element of laboratory assessment for hyperprolactinaemia.In cases where measured total prolactin is significantly raised, quantitative reporting of estimated monomeric prolactin instead of just 'macroprolactin' positive' can avoid unnecessary investigations.

Chirped-pulse amplification with narrowband pulses

We demonstrate a compact hyperdispersion stretcher and compressor pair that permit chirped-pulse amplification in Nd:YAG. We generate 750 mJ, 0.2 nm FWHM, 10 Hz pulses recompressed to an 8 ps near-transform-limited duration. The dispersion-matched pulse compressor and stretcher impart a chirp of 7300 ps/nm, in a 3 m x 1 m footprint.

Isotope-specific detection of low-density materials with laser-based monoenergetic gamma-rays

What we believe to be the first demonstration of isotope-specific detection of a low-Z and low density object shielded by a high-Z and high-density material using monoenergetic gamma rays is reported. The isotope-specific detection of LiH shielded by Pb and Al is accomplished using the nuclear resonance fluorescence line of L7i at 478 keV. Resonant photons are produced via laser-based Compton scattering. The detection techniques are general, and the confidence level obtained is shown to be superior to that yielded by conventional x-ray and gamma-ray techniques in these situations.

OZSPEC-2: an improved broadband high-resolution elliptical crystal x-ray spectrometer for high-energy density physics experiments (invited)

A novel time, space, and energy-resolved x-ray spectrometer has been developed which produces, in a single snapshot, a broadband and relatively calibrated spectrum of the x-ray emission from a high-energy density laboratory plasma. The opacity zipper spectrometer (OZSPEC-1) records a nearly continuous spectrum for x-ray energies from 240 to 5800 eV in a single shot. The second-generation OZSPEC-2, detailed in this work, records fully continuous spectra on a single shot from any two of these three bands: 270-650, 660-1580, and 1960-4720 eV. These instruments thus record thermal and line radiation from a wide range of plasmas. These instruments' single-shot bandwidth is unmatched in a time-gated spectrometer; conversely, other broadband instruments are either time-integrated (using crystals or gratings), lack spectral resolution (diode arrays), or cover a lower energy band (gratings). The OZSPECs are based on the zipper detector, a large-format (100x35 mm) gated microchannel plate detector, with spectra dispersed along the 100 mm dimension. OZSPEC-1 and -2 both use elliptically bent crystals of OHM, RAP, and/or PET. Individual spectra are gated in 100 ps. OZSPEC-2 provides one-dimensional spatial imaging with 30-50 microm resolution over a 1500 microm field of view at the source. The elliptical crystal design yields broad spectral coverage with resolution E/DeltaE>500, strong rejection of hard x-ray backgrounds, and negligible source broadening for extended sources. Near-term applications include plasma opacity measurements, detailed spectra of inertial fusion Hohlraums, and laboratory astrophysics experiments.

Migration is associated with lower total, but not free testosterone levels in South Asian men

OBJECTIVE

Serum testosterone measurement is an integral part of the endocrine assessment of men. Little is known about its variation in relation to migration. We examined within a South Asian group the effect of migration to the UK on androgen levels.

DESIGN

Circulating testosterone and SHBG concentrations were measured in 97 Gujarati men resident in India and in 79 men from the same villages of origin living in Birmingham, UK. Free testosterone was calculated by Vermeulen's method. Insulin sensitivity (HOMA-S) was determined from paired fasting plasma intact insulin and glucose values.

RESULTS

Circulating testosterone was significantly lower in UK Gujarati men (17.2 nmol/l [15.7-18.7]) vs. Indian Gujarati men (21.7 [20.0-23.5]) (P = 0.0002) (age-adjusted median [95% CI]). There was no difference by migration status in circulating free testosterone. Sex hormone binding globulin (SHBG) levels were lower in UK migrants (16.8 nmol/l [15.5-18.1]) than in nonmigrants (21.9 nmol/l [20.5-23.3]) (P < 0.0001). Testosterone level correlated positively with insulin sensitivity (HOMA-S) (rho 0.16, P = 0.04). In multivariate analysis, total testosterone was independently and positively associated with logSHBG (normalized beta (beta) = 0.29, P = 0.002) and independently and negatively with waist circumference (beta = -0.19, P = 0.04), in a model also including height, age, migration status, leptin and fasting insulin.

CONCLUSION

Lower circulating testosterone in UK Gujarati men and its association with markers of insulin sensitivity suggest a profound influence of body composition change with migration on testosterone levels. The lower SHBG in this group restores parity in free testosterone. Account should be taken of SHBG in interpreting testosterone levels in men, as well as in women.

Change in pancreatic B-cell function (HOMA-B) varies in different populations with similar genetic backgrounds but different environments

OBJECTIVE

To determine whether pancreatic B-cell function varies in different populations with similar genetic backgrounds but different environments.

RESEARCH DESIGN/METHODS

We compared a specific migrant Gujarati community in the UK (n = 205) with people still resident in the same villages of origin in Gujarat, India (n = 246). Pancreatic B-cell function (HOMA-B) was determined and the influence of age, migration and other factors was explored.

RESULTS

As anticipated, there was an age-related decline in log(HOMA-B) in both groups. However, the age-related fall in log(HOMA-B) was more pronounced in the UK than in Gujarat (normalized beta-0.29 vs. -0.14, P for difference = 0.03). The decline of HOMA-B with age persisted after adjustment for body mass index (UK beta = -0.31; Gujarat beta = -0.16, P = 0.015, P < 0.001). There was no significant change in insulin sensitivity (HOMA-S) with age at either site, although insulin sensitivity was lower in the UK. Fasting non-estrified fatty acid (NEFA) levels rose with age in the UK but not in Gujarat (P = 0.003 for difference in gradients). In multiple linear regression analysis, lower log(HOMA-B) was independently associated with higher fasting log(NEFA) levels; normalized beta = -0.24, P < 0.001, age; beta = -0.16, P = 0.005, higher log(insulin-like growth factor binding protein-1); beta = -0.19, P = 0.007 and lower body mass index; beta = 0.26, P = 0.001. This model accounted for 25% of the variability in HOMA-B.

CONCLUSIONS

HOMA-B as a measure of B-cell function declines more rapidly with age in the migrant UK group than in Gujarat. This may be a direct consequence of chronically higher NEFA exposure in the UK group.

Dietary intake and the insulin-like growth factor system: effects of migration in two related populations in India and Britain with markedly different dietary intake

Background

The insulin-like growth factor (IGF) system is implicated in the pathogenesis of diabetes and cardiovascular disease.

Objective

We report the effects of total energy intake on the IGF system in two populations with markedly different dietary macronutrient intake and cardiovascular event rate.

Design, subjects and setting

Dietary macronutrient intake was measured in a specific Gujarati migrant community in Sandwell, UK (n = 205) compared with people still resident in the same villages of origin in India (n = 246). Fasting IGF-I, IGF-binding protein (IGFBP)-1 and IGFBP-3, insulin and glucose (0 and 2-hour) were measured.

Results

Total energy and total fat intake were higher in UK migrants, as were IGFBP-3 and IGF-I (mean (95% confidence interval): 145.9 (138.1–153.6) vs. 100.9 (94.6–107.3) ng ml-1; F = 76.6, P < 0.001). IGFBP-1 was lower in UK migrants (29.5 (25.9–33.0) vs. 56.5 (50.6–62.5) μg l-1; F = 48.4, P < 0.001). At both sites, IGF-I correlated positively with total energy (Spearman's ρ = 0.45, P < 0.001) and total fat (ρ = 0.44, P < 0.001) as did IGFBP-3 with total energy (ρ = 0.21, P < 0.05) and fat (ρ = 0.26, P < 0.001). Conversely, in Indian Gujaratis, IGFBP-1 fell with increasing total energy (ρ = -0.27, P < 0.001) and fat intake (ρ = -0.26, P < 0.01) but not in UK Gujaratis. Multiple linear regression modelling showed that increasing quartiles of fat intake were associated with higher IGF-I (β = 0.42, P = 0.007) independent of age, body mass index, plasma insulin, fatty acids and 2-hour glucose.

Conclusion

In these genetically similar groups, migration to the UK and adoption of a different diet is associated with marked changes in the IGF system, suggesting that environmental factors profoundly modulate serum concentrations and actions of IGFs.

Insulin-like growth factor binding protein-2 (IGFBP-2) is a marker for the metabolic syndrome

AIMS/HYPOTHESIS

IGFs and their binding proteins are increasingly recognised as important in understanding the pathogenesis of cardiovascular disease. Low IGFBP-1, particularly coupled with low IGF-I, is associated with increased cardiovascular risk. In relation to structural and regulatory parallels between IGFBP-1 and - 2 we have now examined the hypothesis that IGFBP-2 may be a marker for cardiovascular risk.

METHODS

Fasting IGFBP-2, IGFBP-1, IGFBP-3, IGF-I, IGF-II, insulin, C-peptide, glucose, lipids, NEFAs, and HbA1c were measured in a cohort of 163 patients with type 2 diabetes. Individuals were categorised according to the presence or absence of the metabolic syndrome.

RESULTS

Patients with the metabolic syndrome had a lower IGFBP-2 concentration. Low circulating IGFBP-2 was associated with elevated fasting glucose (rho = - 0.23, p = 0.003). IGFBP-2 correlated negatively with triglycerides (rho = - 0.19, p = 0.01) and LDL-cholesterol (rho = - 0.20, p = 0.01), and positively with insulin sensitivity (HOMA-S) (rho = 0.26, p = 0.02). Multivariate logistic regression demonstrated that low IGFBP-2 was independently associated with an increased risk of the metabolic syndrome (OR 0.31 [95 % CI 0.11 - 0.90]; p = 0.03). IGFBP-3 did not differ according to the presence or absence of metabolic syndrome.

CONCLUSION/INTERPRETATION

Low IGFBP-2 is associated with multiple cardiovascular risk factors similarly to IGFBP-1. Such associations were not apparent for IGFBP-3. Lack of marked prandial regulation of IGFBP-2, in contradistinction to IGFBP-1, may make IGFBP-2 a more robust biomarker for identification of insulin-resistant individuals at high cardiovascular risk in epidemiological studies.

Low sex hormone binding globulin is a potential marker for the metabolic syndrome in different ethnic groups

Hepatic sex-hormone binding globulin (SHBG) production is down-regulated by insulin and low levels reflect insulin resistance. Because insulin resistance is closely related to the development of cardiovascular disease in different ethnic groups we examined ethnic variation in SHBG across populations with different baseline cardiovascular risk and metabolic syndrome prevalence. Participants were population-based, of European (n = 142), Pakistani (n = 130), and African-Caribbean (AfC) origin (n = 193). SHBG, fasting lipids, and glucose concentrations plus insulin sensitivity (HOMA-S) were determined. Age adjusted SHBG was significantly lower in both Pakistani men and women. Circulating SHBG levels were lower in those with impaired vs. normal glucose homeostasis. SHBG correlated positively with HOMA-S (rho = 0.28, p < 0.001), and negatively with WHR (rho = - 0.38, p < 0.001), BMI (r = - 0.30, p < 0.001), and diastolic blood pressure (rho = - 0.14, p < 0.01) across all ethnic groups. In multivariate logistic regression analysis a low SHBG increased the likelihood of the metabolic syndrome (odds ratio [OR] = 0.42 [0.21 - 0.82], p = 0.01) as did higher fasting NEFA (OR 1.47 [1.04 - 2.08], p = 0.03), low IGFBP-1 concentrations (OR 0.6 [0.44 - 0.81], p = 0.001), age (OR 1.05 [1.02 - 1.09], p = 0.003), and Pakistani ethnicity (p = 0.001) in a model which also contained gender, lnCRP, IGF-I, and IGF-II. As ethnic differences in SHBG level closely parallel differences in insulin resistance. Its measurement may be useful in identifying individuals at particular risk of the metabolic syndrome, for early intervention.

Marked differences in the IGF system that are associated with migration in comparable populations of Gujaratis living in Sandwell, UK, and Gujarat, India

AIMS/HYPOTHESES

We previously reported independent links between the IGF system and the development of impaired glucose tolerance and cardiovascular risk. This study tests the hypothesis that the lifestyle change which accompanies population migration, with attendant increases in cardiovascular risk, is reflected by changes in the IGF system.

MATERIALS AND METHODS

We compared a specific Gujarati community in Sandwell, UK (n=205), with people still resident in the same villages of origin near Navsari, India (n=246). We performed anthropometry and measured fasting plasma insulin, IGF-I, insulin-like growth factor binding protein (IGFBP)-1 and IGFBP-3.

RESULTS

Daily calorie intake, BMI and WHR were significantly higher in UK Gujaratis than in Indian Gujaratis. IGFBP-1 was significantly lower in UK migrants (mean 29.5 [95% CI 25.9-33.0] vs 56.5 [50.6-62.5] microg/l; F=48.4, p<0.001). Conversely, fasting insulin, IGFBP-3 and IGF-I were all higher in UK Gujaratis (mean IGF-I 145.9 [138.1-153.6]ng/ml in UK Gujaratis and 100.9 [94.6-107.3] ng/ml in Navsari Gujaratis; F=76.6, p<0.001). These differences were still apparent when adjustment was made for BMI by location for IGF-I (F=57.4, p<0.001) and IGFBP-3 (F=5.7, p=0.02), but were no longer apparent for IGFBP-1 and insulin. At the population level, the decrease in IGFBP-1 for a given increase in insulin was significantly smaller in UK Gujaratis, suggesting greater hepatic insulin resistance in this group.

CONCLUSIONS/INTERPRETATION

Environmental factors have profound effects on circulating IGF system components and on the relationship between IGFBP-1, IGF-I and related metabolic variables. This may have long-term implications for the development of worsening glucose tolerance and cardiovascular disease.

Horizontal phase-space distortions arising from magnetic pulse compression of an intense, relativistic electron beam

We report detailed measurements of the transverse phase space distortions induced by magnetic chicane compression of a high brightness, relativistic electron beam to subpicosecond length. A strong bifurcation in the phase space is observed when the beam is strongly compressed. This effect is analyzed using several computational models and is correlated to the folding of longitudinal phase space. The impact of these results on current research in collective beam effects in bending systems and implications for future short wavelength free-electron lasers and linear colliders are discussed.

Natural history and prognostic factors of diabetic nephropathy in type 2 diabetes

BACKGROUND

The causes and mechanisms of increased mortality of patients with diabetic nephropathy are unclear, and its natural history is poorly understood.

AIM

To evaluate risk factors for mortality in type 2 diabetic patients with nephropathy.

DESIGN

Retrospective study of clinical and biochemical parameters in diabetic nephropathic patients and controls sampled from a secondary care register.

METHODS

We studied 170 type 2 diabetic patients (from 1987 to 1995) with nephropathy (proteinuria >0.5 g/24 h) and 170 non-nephropathic patients. Follow-up was until death or December 1997. Details of demographics, clinical and treatment history were obtained from medical records.

RESULTS

Mean follow-up was 5.3 years. Of the patients with nephropathy at baseline, 63 (37%) died compared with 14 (8%) non-nephropathic patients (chi(2)=53.8, p<0.0001). Age- and sex-adjusted all-cause mortality rates were 8.1 (6.4, 9.8) and 1.4 (0.5, 2.2) deaths per 100 person-years, respectively (rate ratio 5.8). Forty-four patients (57%) died from cardiovascular causes (rate ratio 5.4). Mortality was directly proportional to degree of proteinuria: 0.5-2 g/24 h, 4.6 (2.9-7.1); >2 g/24 h, 9.9 (7.3-13.5) per 100 patient-years. A 36% (5-78%) excess risk of mortality was observed for each log unit increase in proteinuria. Multivariate Cox regression analyses confirmed a five-fold excess risk for all-cause and cardiovascular mortality in patients with nephropathy compared with those without. This was independent of other risk factors including baseline age [5% (1-8%)/year], creatinine [2.5 (1.12-5.6)/10 micromol/l] and glycaemic control (HbA(1c)) [15% (1-31%) per 1% rise].

CONCLUSIONS

Proteinuria is a potentially preventable and reversible risk factor associated with high mortality in type 2 diabetic patients. Prevention of the development of overt nephropathy and improvement in diabetes control may reduce mortality in these patients.

Hypertension in four African-origin populations: current 'Rule of Halves', quality of blood pressure control and attributable risk of cardiovascular disease

OBJECTIVE

To assess the public health burden from high blood pressure and the current status of its detection and management in four African-origin populations at emerging or high cardiovascular risk.

DESIGN

Cross-site comparison using standardized measurement and techniques.

SETTING

Rural and urban Cameroon; Jamaica; Manchester, Britain.

SUBJECTS

Representative population samples in each setting. African-Caribbeans (80% of Jamaican origin) and a local European sample in Manchester.

MAIN OUTCOME MEASURES

Cross-site age-adjusted prevalence; population attributable risk.

RESULTS

Among 1,587 men and 2,087 women, age-adjusted rates of blood pressure > or =160 or 95 mmHg or its treatment rose from 5% in rural to 17% in urban Cameroon, despite young mean ages, to 21% in Jamaica and 29% in Caribbeans in Britain. Treatment rates reached 34% in urban Cameroon, and 69% in Jamaican- and British-Caribbean-origin women. Sub-optimal blood pressure control (> 140 and 90 mmHg) on treatment reached 88% in European women. Population attributable risks (or fractions) indicated that up to 22% of premature all-cause, and 45% of stroke mortality could be reduced by appropriate detection and treatment. Additional benefit on just strokes occurring on treatment could be up to 47% (e.g. in both urban Cameroon men and European women) from tighter blood pressure control on therapy. Cheap, effective therapy is available.

CONCLUSION

With mortality risk now higher from non-communicable than communicable diseases in sub-Saharan Africa and elsewhere, systematic measurement, detection and genuine control of hypertension once treated can go hand-in-hand with other adult health programmes in primary care. Cost implications are not great. The data from this collaborative study suggest that such efforts should be well rewarded.

Diabetes in the Caribbean: results of a population survey from Spanish Town, Jamaica

AIMS

To characterize the prevalence of diabetes and associated risk attributes in the Jamaican population.

METHODS

A random population sample was recruited by door-to-door canvassing (n = 1303). A final participation of 60% was achieved. Oral glucose tolerance testing was conducted after an overnight fast and standard anthropometric and demographic data were collected.

RESULTS

The prevalence of Type 2 diabetes mellitus was 9.8% (95% confidence interval (CI) 7.2-12.4) among men and 15.7% (95% CI 13.1-18.3) among women with an overall prevalence of 13.4% (95% CI 11.5-15.2). Impaired glucose tolerance was found among 12.3% of men and 14.7% of women. The sex patterns were consistent with a fourfold excess of obesity in women compared to men. The odds ratios for diabetes, fourth vs. first quartiles were 5.42 (95% CI 2.02-16.88) in men and 3.32 (95% CI 1.73-6.63) in women for body mass index (BMI) and 17.39 (95% CI 3.86-78.27) in men and 5.48 (95% CI 2.84-11.00) in women for WHR in a logistic model controlling for age. The population attributes risk percentage, for diabetes, of being overweight and having waist-to-hip ratio (WHR) greater than the median (0.80) were 66% and 80%, respectively. The contribution of central obesity, as characterized by WHR, was also significant in sex-specific multivariate models that included age and BMI. Prevalent hypertension and family history of diabetes were likewise associated with increased odds of having the disease.

CONCLUSIONS

The prevalence of diabetes in Jamaica now exceeds that observed among European-origin populations and reflects the emerging epidemic of obesity. The excess risk for this population could not be attributed entirely to relative weight. The pronounced sexual dimorphism in diabetes prevalence most likely reflects the substantial excess of obesity among women compared to men. Like many other island nations, Caribbean societies now appear to be at substantial risk of diabetes.

The potential role of cell adhesion molecules in the pathogenesis of diabetic neuropathy

Cross-sectional studies have shown plasma cell adhesion molecules (CAMs) to be increased in patients with diabetes-related complications. In the first prospective study of CAMs, we have shown that plasma CAMs may be a predictor of the development of diabetic neuropathy. We followed up 28 diabetic patients (13 neuropathic) over a 5 year period, starting from 1991. All patients had peroneal nerve conduction velocity (PNCV), vibration perception threshold and plasma CAMs measured at baseline and follow-up. We found P-selectin and intercellular adhesion molecule-1 (ICAM-1) to be increased at baseline in patients with neuropathy compared to non-neuropathic patients. P-selectin and E-selectin were also found to be significantly higher at baseline in patients who at follow-up showed deterioration in PNCV of more than 3 m/s (p<0.05; p=0.01; respectively). P-selectin and ICAM-1 strongly correlated with PNCV. Univariate and multivariate regression analyses showed a significant inverse association between increasing log P-selectin, log E-selectin and log ICAM-1 with decreasing PNCV, and remained significant even after adjustment for glycaemic control. P-selectin and E-selectin, odds ratios of 8.8 (95% CI: 1.1-68.8; p=0.038) and 12.5 (95% CI: 1.2-132.1; p=0.036), respectively, were significantly associated with the risk of deterioration of PNCV after 5 years. This study suggests that plasma cell adhesion molecules may play an important role in the development and progression of peripheral neuropathy in diabetes mellitus.

Pathogenesis of hemorrhage induced by proteinase H from eastern diamondback rattlesnake (Crotalus adamanteus) venom

The pathogenesis of hemorrhage of a purified hemorrhagic toxin, proteinase H from Crotalus adamanteus venom, was studied. Female, white CD-1 mice were injected intramuscularly with sublethal doses of the hemorrhagic toxin and tissue samples were obtained at 10 min, 1, 3 and 24 hr following injection. Severe local hemorrhage was observed grossly within 10 min. Hemorrhage was observed in the connective tissue of skeletal muscle and within adjacent adipose tissue. Many larger vessels were congested with erythrocytes and platelets. By 3 hr inflammatory cell infiltration was observed and necrosis of some muscle cells was evident. Transmission electron microscopy showed that the capillary endothelium was ruptured, leading to hemorrhage per rhexis. Capillary basal laminae were disorganized and often wholly or partially absent.

Systemic hemorrhage induced by proteinase H from Crotalus adamanteus (eastern diamondback rattlesnake) venom

The systemic effects of a purified hemorrhagic toxin, proteinase H, from Crotalus adamanteus venom, were studied. Female, white CD-1 mice were injected intravenously with proteinase H and tissue samples were obtained at 1, 3 and 24 hr after injection. Hemorrhage was observed grossly within 1 hr in several internal organs including the stomach and small intestine, the heart and the lungs. Surface discolorations thought to be petechial hemorrhages were observed in the kidneys. The livers of treated animals were visibly swollen and darkened and lobules were accentuated. Tissue samples were taken from the stomach, duodenum, heart, lungs, liver and kidneys and prepared for observation by light and electron microscopy. Frank hemorrhage was observed by light microscopy in the walls of the stomach and duodenum, in the myocardium and in the lungs. Pulmonary hemorrhage was severe, with involvement of nearly all of the pulmonary tissue within 3 hr. A1 doses of 5 micrograms/g, hepatic degeneration was observed by 3 hr. Renal glomeruli were noticeably swollen and the lumena of the proximal convoluted tubules indistinct. Closer examination by electron microscopy revealed that the endothelial cells comprising the fenestrated glomerular capillaries remained intact but signs of degeneration (i.e. cytoplasmic swelling and mitochondrial swelling) were observed. Proteinase H induces systemic hemorrhage in the heart, lungs, stomach and small intestine, renal glomerulonephropathy and hepatic degeneration.

Treatment considerations in postmastectomy reconstruction: their relative importance and relationship to patient satisfaction

Although studies concerning motivation for and satisfaction with breast reconstruction after mastectomy have proliferated, little information is available concerning the relative importance of motivating factors and satisfaction with treatment choice in nonreconstructed and reconstructed mastectomy patients. We studied this by questioning 144 women in four groups: mastectomy patients who had reconstruction; mastectomy patients who did not have reconstruction; and two control groups composed of women who had not had any cancer or who had undergone hysterectomy for uterine cancer. This study was conducted just before the reports of alleged risks of silicone to the patients and reflects the opinions of patients without such bias. This study shows that, although women who opted for reconstruction reported greater concern about appearance than women who did not have reconstruction, both groups described concerns about surgical discomfort and possible complications. Also, women's concerns about appearance did not seem to fall solely into public (others' evaluations) or private (patients' own evaluation) domains. Rather, personal attitudes about appearance may affect interpersonal experiences. Finally, concerns about the possibility of recurrence may reduce patient satisfaction for some women who have reconstruction, so postsurgical education regarding cancer risk may be needed. Reconstructed and nonreconstructed mastectomy patients do not appear to differ in postoperative behaviors promoting personal health. This information, analyzed before the silicone controversy, may serve as a baseline for future research on the impact of the silicone crisis on women's perceptions regarding reconstruction.

Comparison of the immunogenicity and antigenic composition of ten Central American snake venoms

The immunological reactivity of five crotaline antivenoms for the venoms of ten Costa Rican snakes was determined. Venoms from Bothrops asper, B. godmani, B. lateralis, B. nasutus, B. ophryomegas, B. schlegelii, B. nummifer, B. picadoi, Crotalus durissus durissus and Lachesis muta stenophrys were separated by SDS-PAGE, transferred to cellulose nitrate membrane and reacted against five different antivenoms. Antisera used in the immunoblotting were prepared in rabbits to the crotaline venoms from Crotalus viridis viridis (prairie rattlesnake), Crotalus durissus terrificus (South American rattlesnake), Crotalus atrox (western diamondback rattlesnake), and Bothrops atrox (fer de lance). SDS-PAGE analysis of the ten venoms indicated that all venoms had components in the high-medium mol. wt (> 15,000) and low mol. wt (< 15,000) range, but they all had at least twice as many components in the high-medium mol. wt range. The venoms of B. nummifer and B. nasutus have the greatest number of bands (24) whereas B. asper has the lowest (17). There appeared to be no difference in immunogenicity between high-medium mol. wt components and low mol. wt components; however, with the venoms of B. nasutus, B. ophryomegas, and B. schlegelii, there were few reactions between antivenoms and low mol. wt components. Half of the ten venoms tested had the highest reactivity with antivenom against B. atrox venom. Two venoms reacted most with antivenom against C. adamanteus venom; one with antivenom to C. atrox venom; one with antivenom to C. v. viridis venom and one with antivenom to C. d. terrificus venom.(ABSTRACT TRUNCATED AT 250 WORDS)

A high transmission hemispherical energy analyzer for ion spectrometry

A hemispherical energy analyzer was constructed by using a novel approach to control the fringing electrostatic field. It provides several properties useful in ion spectrometers: namely, rather simple fabrication and compact size, high transmission efficiency at moderate resolution, and the capability to adjust resolution by changing the intersphere potentials. A computer program was developed to evaluate ion trajectories through the hemispherical analyzer. Data obtained from the trajectories were used to predict the characteristics of the analyzer. Experiments performed to determine the kinetic energy dependence of the absolute transmission and the resolution functions are in accord with theoretical calculations.

Neonatal gram negative meningitis: a 10-year review, with reference to outcome and relapse of infection

Twenty-four infants treated for neonatal Gram negative bacillary meningitis over a 10-year period were reviewed to determine the mortality and incidence of complications including relapse. Nine (37.5%) infants died; two survivors had major and 13 minimal or no handicap. Five (21%) infants had a relapse of meningitis after the initial course of treatment; two of these infants had been treated with cefotaxime. The outcome did not correlate with age, sex, gestation, cerebrospinal fluid (CSF) parameters or peripheral neutrophil counts. A poor outcome was associated with thrombocytopenia, persistence of viable organisms in the CSF for more than 24 h and with seizures, particularly in infants aged 7 days or less. There were no clinical or laboratory parameters predictive of subsequent relapse and there was no apparent relationship with choice or dose of antibiotic used or duration of treatment.

A recessive mutation causing imperforate vagina in mice

A recessive mutation (ipv) causing imperforate vagina was discovered in a line of mice selected for low lean tissue mass as a proportion of body weight. Two full sisters were found to have marked swelling of the perineum and complete closure of the vagina. Crosses of heterozygotes identified by progeny testing produced a female progeny ratio not different from the 3 normal: 1 affected (chi 2 = 0.695; p less than .3) expected on the basis of a recessive allele at a single autosomal locus. As a consequence of the imperforate vagina, the uterus and vagina were greatly distended by fluid. The uterus of affected females displayed a swollen uterine lumen and thin endometrial stroma and muscularis. Ovarian tissue of affected females was similar to that of normal mice, and affected females produced ova that were normal in appearance. The mutation causing an imperforate vagina may present a useful model for studying the basis of abnormal vaginal development in other species and increasing the understanding of normal vaginal development in the mouse.