Estimating the burden of disease attributable to diabetes in South Africa in 2000

Objectives. To estimate the burden of disease attributable to diabetes by sex and age group in South Africa in 2000. Design. The framework adopted for the most recent World Health Organization comparative risk assessment (CRA) methodology was followed. Small community studies used to derive the prevalence of diabetes by population group were weighted proportionately for a national estimate. Populationattributable fractions were calculated and applied to revised burden of disease estimates. Monte Carlo simulation-modelling techniques were used for uncertainty analysis. Setting. South Africa. Subjects. Adults 30 years and older. Outcome measures. Mortality and disability-adjusted life years (DALYs) for ischaemic heart disease (IHD), stroke, hypertensive disease and renal failure. Results. Of South Africans aged ≥ 30 years, 5.5% had diabetes which increased with age. Overall, about 14% of IHD, 10% of stroke, 12% of hypertensive disease and 12% of renal disease burden in adult males and females (30+ years) were attributable to diabetes. Diabetes was estimated to have caused 22 412 (95% uncertainty interval 20 755 - 24 872) or 4.3% (95% uncertainty interval 4.0 - 4.8%) of all deaths in South Africa in 2000. Since most of these occurred in middle or old age, the loss of healthy life years comprises a smaller proportion of the total 258 028 DALYs (95% uncertainty interval 236 856 - 290 849) in South Africa in 2000, accounting for 1.6% (95% uncertainty interval 1.5 - 1.8%) of the total burden. Conclusions. Diabetes is an important direct and indirect cause of burden in South Africa. Primary prevention of the disease through multi-level interventions and improved management at primary health care level are needed

The epidemic of obesity in South Africa: a study in a disadvantaged community.

Objective: The objective of this study was: 1) to determine the anthropometric profile of adults In Mamre, a small town In South Africa, which has a population of mixed ancestry ("colored" people of Afro-Euro-Malay-Khoisan ancestry); and 2) to determine the change In this profile between 1989 and 1996. Design: Cross-sectional surveys conducted In random samples of adults In 1989 and 1996. Participants: The subjects were 684 women and 529 men In 1989, and 546 women and 430 men In 1996, aged 15 and older. Main Outcome Measures; The following measurements were recorded: height, weight, and circumference of waist, hips, and mid-upper arm. Results: Based on data from the 1996 survey, 32% of women are obese (body mass index [BMI] ;;: 30) at ages 25-44 years, rising to 49% at ages 45-64 years. A much lower prevalence of obesity is seen in men: 14"10 at ages 35-64 years. Obesity levels significantly increased in women between the two surveys (P=.015): up from 44% in 1989 to 49% in 1996 at ages 45-64 years. There was an Increase In the prevalence of overweight (BMI 25-29.9) in men, though not in obesity. Mean 8MI increased by about 3% In women and 2% in men between 1989 and 1996. Conclusions; This study conducted among people of mixed ancestry living In a disadvantaged community In South Africa shows that half of middle-aged women are obese. A rising trend In 8MI was seen in adults of both sexes between 1989 and 1996. This trend may be explained by factors associated with rural-urban transition, Including electrification, reduced physical activity, and Increasing availability of energy-dense food

Waist circumference predicts clustering of cardiovascular risk factors in older South Africans

Objecti~'eand design. A cross-sectional analytical study to determine the cardiovascular risk factor profile of older residents of fishing villages on the West Coast of South Africa, and to det.ermine which anthropometric measures are associated with risk factors. Subjects. A convenient community-based sample of 152 subjects of mixed ancestry aged 55 years and over was recruited door-to-door using an address list of ageeligible subjects provided by the local public health care clinics. Methods. Cardiovascular relationships were im'estigated between: (i) number of risk factors (hypertension, hypercholesterolaemia, diabetes) and body mass index (8MI), waist-to-hip ratio (WHR), and waist circumference; and (ii) continuous cardiovascular risk factor variables and physical activity, smoking, dietary intake, and 24-hour urinary sodium and potassium concentrationS. Results. The prevalence of hypertension (~ 160/95 mmHg) was 74.3% (95% CI: 67.2 - 81.4%). Neither 24- hour urinary sodium nor potassium concentrations was associated with blood pressure (BP). Past, but not present, moderate-intensity physical activity, particularly that associated with occupation, was negatively associated with systolic BP (r = -0.24, P < 0.05). The prevalence of diabetes and hypercholesterolaemia (serum cholesterol ~ 6.5 mmolll) was 24.6% (95% CI: 17.2 - 32%) and 40% (95% CI: 31.8 - 48.2%),respectively. The percentage of subjects with 0, 1, or 2 or more cardiovascular risk factors was 13.4%,44.1% and 42.5%, respectively. Subjects with a waist circumference ~ 92 em had a significantly higher number of cardiovascular risk factors than those with a waist circumference < 92 cm (Xl =9.29, P < 0.01), and this association remained significant even after controlling for age, sex and smoking (P < 0.05). Neither 8MI tertiles according to sex, nor a 8MI cut-point ~ 30, was significantly associated with a clustering of risk factors. COllclusioll. In a sample of older South Africans of ntlxed ancestry at high risk of cardiovascular disease, waist circumference ~ 92 em predicts clustering of risk factors, Independentl)' of BMI. This simple, populationspecific reference value may provide a useful screening tool to identify at-risk Individuals for targeted prevention for coronary heart disease and associated metabolic disorders

Dietary intake and barriers to dietary compliance in black type 2 diabetic patients attending primary health-care services

OBJECTIVE: To determine the dietary intake, practices, knowledge and barriers to dietary compliance of black South African type 2 diabetic patients attending primary health-care services in urban and rural areas. DESIGN: A cross-sectional survey. Dietary intake was assessed by three 24-hour recalls, and knowledge and practices by means of a structured questionnaire (n = 133 men, 155 women). In-depth interviews were then conducted with 25 of the patients to explore their underlying beliefs and feelings with respect to their disease. Trained interviewers measured weight, height and blood pressure. A fasting venous blood sample was collected from each participant in order to evaluate glycaemic control. SETTING: An urban area (Sheshego) and rural areas near Pietersburg in the Northern Province of South Africa. SUBJECTS: The sample comprised 59 men and 75 women from urban areas and 74 men and 80 women from rural areas. All were over 40 years of age, diagnosed with type 2 diabetes for at least one year, and attended primary health-care services in the study area over a 3-month period in 1998. RESULTS: Reported dietary results indicate that mean energy intakes were low ( or = 30 kg m(-2)) was prevalent in 15 to 16% of men compared with 35 to 47% of women; elevated blood pressure (> or = 160/95 mmHg) was least prevalent in rural women (25.9%) and most prevalent in urban men (42.4%). CONCLUSIONS: The majority of black, type 2 diabetic patients studied showed poor glycaemic control. Additionally, many had dyslipidaemia, were obese and/or had an elevated blood pressure. Quantitative and qualitative findings indicated that these patients frequently received incorrect and inappropriate dietary advice from health educators

‘Short Interest Pressure’ and Competitive Behaviour

This study introduces and examines a new-to-strategy form of Wall Street pressure – ‘short interest pressure’ – the tension felt by management caused by short sales of the firm\u27s stock. Drawing from a sample of over 5000 competitive actions carried out by competing firms over a 6-year time period, we test whether the level of short interest pressure experienced by the firm in one time period is predictive of properties of the firm\u27s competitive action repertoire in the ensuing time period. Our findings suggest that when faced with short interest pressure firms tend to carry out a higher number of competitive actions in the following time period, as well as a set of actions that deviate from the industry norm. In addition, post hoc analysis reveals that this effect is amplified for poorly performing firms. Thus, our study contributes to a deeper understanding of the relationship between capital market signals and competitive strategy

Spin-locking in low-frequency reaction yield detected magnetic resonance

The purported effects of weak magnetic fields on various biological systems from animal magnetoreception to human health have generated widespread interest and sparked much controversy in the past decade. To date the only well established mechanism by which the rates and yields of chemical reactions are known to be influenced by magnetic fields is the radical pair mechanism, based on the spin-dependent reactivity of radical pairs. A diagnostic test for the operation of the radical pair mechanism was proposed by Henbest et al. [J. Am. Chem. Soc., 2004, 126, 8102] based on the combined effects of weak static magnetic fields and radiofrequency oscillating fields in a reaction yield detected magnetic resonance experiment. Here we investigate the effects on radical pair reactions of applying relatively strong oscillating fields, both parallel and perpendicular to the static field. We demonstrate the importance of understanding the effect of the strength of the radiofrequency oscillating field; our experiments demonstrate that there is an optimal oscillating field strength above which the observed signal decreases in intensity and eventually inverts. We establish the correlation between the onset of this effect and the hyperfine structure of the radicals involved, and identify the existence of ‘overtone’ type features appearing at multiples of the expected resonance field positio

The short-term effect of high versus moderate protein intake on recovery after strength training in resistance-trained individuals

Background: Dietary protein intakes up to 2.9 g.kg-1.d-1 and protein consumption before and after resistance training may enhance recovery, resulting in hypertrophy and strength gains. However, it remains unclear whether protein quantity or nutrient timing is central to positive adaptations. This study investigated the effect of total dietary protein content, whilst controlling for protein timing, on recovery in resistance trainees. Methods: Fourteen resistance-trained individuals underwent two 10-day isocaloric dietary regimes with a protein content of 1.8 g.kg-1.d-1 (PROMOD) or 2.9 g.kg-1.d-1 (PROHIGH) in a randomised, counterbalanced, crossover design. On days 8-10 (T1-T3), participants undertook resistance exercise under controlled conditions, performing 3 sets of squat, bench press and bent-over rows at 80% 1 repetition maximum until volitional exhaustion. Additionally, participants consumed a 0.4 g.kg-1 whey protein concentrate/isolate mix 30 minutes before and after exercise sessions to standardise protein timing specific to training. Recovery was assessed via daily repetition performance, muscle soreness, bioelectrical impedance phase angle, plasma creatine kinase (CK) and tumor necrosis factor-α (TNF-α). Results: No significant differences were reported between conditions for any of the performance repetition count variables (p>0.05). However, within PROMOD only, squat performance total repetition count was significantly lower at T3 (19.7 ± 6.8) compared to T1 (23.0 ± 7.5; p=0.006). Pre and post-exercise CK concentrations significantly increased across test days (p≤0.003), although no differences were reported between conditions. No differences for TNF-α or muscle soreness were reported between dietary conditions. Phase angle was significantly greater at T3 for PROHIGH (8.26 ± 0.82°) compared with PROMOD (8.08 ± 0.80°; p=0.012). Conclusions: When energy intake and peri-exercise protein intake was controlled for, a short term PROHIGH diet did not improve markers of muscle damage or soreness in comparison to a PROMOD approach following repeated days of intensive training. Whilst it is therefore likely that protein intakes (1.8g.kg-1.d-1) may be sufficient for resistance-trained individuals, it is noteworthy that both lower body exercise performance and bioelectrical phase angle were maintained with PROHIGH. Longer term interventions are warranted to determine whether PROMOD intakes are sufficient during prolonged training periods or when extensive exercise (e.g. training twice daily) is undertaken

Short-Term Visual Deprivation Does Not Enhance Passive Tactile Spatial Acuity

An important unresolved question in sensory neuroscience is whether, and if so with what time course, tactile perception is enhanced by visual deprivation. In three experiments involving 158 normally sighted human participants, we assessed whether tactile spatial acuity improves with short-term visual deprivation over periods ranging from under 10 to over 110 minutes. We used an automated, precisely controlled two-interval forced-choice grating orientation task to assess each participant's ability to discern the orientation of square-wave gratings pressed against the stationary index finger pad of the dominant hand. A two-down one-up staircase (Experiment 1) or a Bayesian adaptive procedure (Experiments 2 and 3) was used to determine the groove width of the grating whose orientation each participant could reliably discriminate. The experiments consistently showed that tactile grating orientation discrimination does not improve with short-term visual deprivation. In fact, we found that tactile performance degraded slightly but significantly upon a brief period of visual deprivation (Experiment 1) and did not improve over periods of up to 110 minutes of deprivation (Experiments 2 and 3). The results additionally showed that grating orientation discrimination tends to improve upon repeated testing, and confirmed that women significantly outperform men on the grating orientation task. We conclude that, contrary to two recent reports but consistent with an earlier literature, passive tactile spatial acuity is not enhanced by short-term visual deprivation. Our findings have important theoretical and practical implications. On the theoretical side, the findings set limits on the time course over which neural mechanisms such as crossmodal plasticity may operate to drive sensory changes; on the practical side, the findings suggest that researchers who compare tactile acuity of blind and sighted participants should not blindfold the sighted participants