Screening intervals for diabetic retinopathy and incidence of visual loss: a systematic review

Screening for diabetic retinopathy can help to prevent this complication, but evidence regarding frequency of screening is uncertain. This paper systematically reviews the published literature on the relationship between screening intervals for diabetic retinopathy and the incidence of visual loss. The PubMed and EMBASE databases were searched until December 2012. Twenty five studies fulfilled the inclusion criteria, as these assessed the incidence/prevalence of sight-threatening diabetic retinopathy in relation to screening frequency. The included studies comprised 15 evaluations of real-world screening programmes, three studies modelling the natural history of diabetic retinopathy and seven cost-effectiveness studies. In evaluations of diabetic retinopathy screening programmes, the appropriate screening interval ranged from one to four years, in people with no retinopathy at baseline. Despite study heterogeneity, the overall tendency observed in these programmes was that 2-year screening intervals among people with no diabetic retinopathy at diagnosis were not associated with high incidence of sight-threatening diabetic retinopathy. The modelling studies (non-economic and economic) assessed a range of screening intervals (1-5 years). The aggregated evidence from both the natural history and cost-effectiveness models favors a screening interval >1 year, but ≤2 years. Such an interval would be appropriate, safe and cost-effective for people with no diabetic retinopathy at diagnosis, while screening intervals ≤1 year would be preferable for people with pre-existing diabetic retinopathy. A 2-year screening interval for people with no sight threatening diabetic retinopathy at diagnosis may be safely adopted. For patients with pre-existing diabetic retinopathy, a shorter interval ≤1 year is warranted.

Long-term effects of a randomised trial of a 6-year lifestyle intervention in impaired glucose tolerance on diabetes-related microvascular complications: the China Da Qing Diabetes Prevention Outcome Study

AIMS/HYPOTHESIS

We determined the effects of 6 years of lifestyle intervention in persons with impaired glucose tolerance (IGT) on the development of retinopathy, nephropathy and neuropathy over a 20 year period.

METHODS

In 1986, 577 adults with IGT from 33 clinics in Da Qing, China were randomly assigned by clinic to a control group or one of three lifestyle intervention groups (diet, exercise, and diet plus exercise). Active intervention was carried out from 1986 to 1992. In 2006 we conducted a 20 year follow-up study of the original participants to compare the incidence of microvascular complications in the combined intervention group vs the control group.

RESULTS

Follow-up information was obtained on 542 (94%) of the 577 original participants. The cumulative incidence of severe retinopathy was 9.2% in the combined intervention group and 16.2% in the control group (p = 0.03, log-rank test). After adjusting for clinic and age, the incidence of severe retinopathy was 47% lower in the intervention group than the control group (hazard rate ratio 0.53, 95% CI 0.29-0.99, p = 0.048). No significant differences were found in the incidence of severe nephropathy (hazard rate ratio 1.05, 95% CI 0.16-7.05, intervention vs control, p = 0.96) or in the prevalence of neuropathy (8.6% vs 9.1%, p = 0.89) among the 20 year survivors.

CONCLUSIONS/INTERPRETATION

Lifestyle intervention for 6 years in IGT was associated with a 47% reduction in the incidence of severe, vision-threatening retinopathy over a 20 year interval, primarily due to the reduced incidence of diabetes in the intervention group. However, similar benefits were not seen for nephropathy or neuropathy.

The metabolic syndrome: useful concept or clinical tool? Report of a WHO Expert Consultation

This article presents the conclusions of a WHO Expert Consultation that evaluated the utility of the 'metabolic syndrome' concept in relation to four key areas: pathophysiology, epidemiology, clinical work and public health. The metabolic syndrome is a concept that focuses attention on complex multifactorial health problems. While it may be considered useful as an educational concept, it has limited practical utility as a diagnostic or management tool. Further efforts to redefine it are inappropriate in the light of current knowledge and understanding, and there is limited utility in epidemiological studies in which different definitions of the metabolic syndrome are compared. Metabolic syndrome is a pre-morbid condition rather than a clinical diagnosis, and should thus exclude individuals with established diabetes or known cardiovascular disease (CVD). Future research should focus on: (1) further elucidation of common metabolic pathways underlying the development of diabetes and CVD, including those clustering within the metabolic syndrome; (2) early-life determinants of metabolic risk; (3) developing and evaluating context-specific strategies for identifying and reducing CVD and diabetes risk, based on available resources; and (4) developing and evaluating population-based prevention strategies.

Awareness about diabetes and its complications in the general and diabetic population in a city in southern India

OBJECTIVE

The study was done to find out the levels of awareness on diabetes in urban adult Indian population and to identify factors that influenced the awareness, including presence of diabetes.

RESEARCH DESIGN AND METHODS

In population aged > or =20 years (n=3681, M=1769, F=1912), details regarding awareness about diabetes in relation with physical activity, healthy and unhealthy diet, causes, symptoms, prevention, complications and measures to improve health were collected using a questionnaire. A high total score indicated good knowledge. Influence of age, gender, educational status, occupation and presence of diabetic history was analysed.

RESULTS

Fifty percent of subjects scored less than 15. Maximum scored was 51/65. The median total score was 16. Total score was significantly lower in women than in men (15.0 versus 17.0, p<0.0001). Educational status was low in women. Higher education (16.0 versus 12.0, p<0.0001) and professional or executive jobs (17.0 versus 15.0, p<0.0001) were significantly associated with better awareness. Age had no influence. Knowledge regarding causes of diabetes, its prevention and the methods to improve health was significantly low among the general population. Diabetic subjects had better knowledge about symptoms of diabetes and the preventive aspects.

CONCLUSIONS

The low median score indicated that the awareness was generally poor. The score was low especially in women and subjects with low education. The study highlights the urgent need for strategies to spread awareness about diabetes in the general population. Diabetic subjects also required better education on many aspects.

Glucose intolerance and associated factors in the multi-ethnic population of the United Arab Emirates: results of a national survey

AIMS

To determine the prevalence of diabetes and impaired fasting glycaemia (IFG) and associated conditions such as obesity and hypertension, in the multi-ethnic, adult population of the United Arab Emirates in 1999-2000.

METHODS

A stratified, multistage, random sample was selected. Diagnosis was based on the latest recommendations of a WHO Expert Group.

RESULTS

The overall response rate was 89%. Crude prevalence of diabetes was 20%. It was higher in UAE citizens (25%) than in expatriates (13-19% depending on country of origin). Prevalence of diabetes rose with age to a maximum of 40% after the age of 55 years. Prevalence of impaired fasting glycaemia was 5% in men and 7% in women. Forty-one percent of subjects with diabetes were undiagnosed prior to the survey. Of the previously diagnosed subjects with diabetes, 59% were taking oral hypoglycaemic agents, 8% used insulin and 17% relied on diet alone. Obesity was common in all ethnic groups. Approximately three-quarters of all subjects were either obese (BMI> or =30) or overweight (BMI 25-29). Presence of diabetes was associated with increasing waist-hip ratio (WHR), age and with systolic blood pressure and ethnicity. Co-morbidity with glucose intolerance occurred with obesity in 8% and with hypertension in 5%. Three-quarters of all subjects had one or more of these conditions.

CONCLUSIONS

Diabetes, obesity and hypertension are extremely prevalent in the adult population of the UAE. Prompt action is required to avert a major public health crisis due to the long-term complications of diabetes in the near future.

β-Cell Secretory Function and CD25 + Lymphocyte Subsets In the Early Stage of Type 1 Diabetes Mellitus

Cellular immunologic tests have not been used for diagnostic purposes in individuals at risk for autoimmune insulitis or in patients with partial beta-cell destruction because of a lack of studies that show their predictive value. In this study we initially evaluated 43 patients with recent-onset Type 1 diabetes (disease duration <or= 6 months, 29 ICA positive) with regard to beta-cell secretion stimulation test with glucagon and immunologic parameters, including CD4 +, CD8 +, CD4 + CD25 +, CD8 + CD25 + lymphocyte subsets. At baseline, C-peptide concentration 6 min after stimulation increased on average by 0.18 +/- 0.27 micro g/ml. The percentage of CD4 + cells was 42 +/- 9,4 % (healthy controls 44 +/- 7.3 %, p nonsig.) and percentage of CD8 + was 33 +/- 8.6 % (healthy control 31 +/- 8.3 %, p nonsig.). Relative size of CD4 + CD25 + subpopulation was 7 +/- 5.4 % (healthy control 2 +/- 2 %, p < 0.001). Percentage of activated CD8 + cell subset was also increased (2 +/- 1.4 vs. 1.0 +/- 1.0 %), but not significantly. Functional beta-cell testing was repeated after 6 months and nineteen patients were eligible for analysis. Their response was weaker after 6 months (0.13 +/- 0.1 micro g/ml, p < 0.05 vs. baseline). The average change in C-peptide excursion from baseline to the endpoint was - 0.07 +/- 0.17 micro g/ml. There was no significant correlation between beta-cell functional parameters at baseline (C-peptide6min (baseline)) and the relative size of various T cell subpopulations. Results were identical for the 6-month beta-cell functional data (C-peptide6min (6month)). The change in the excursion of C-peptide between baseline and follow-up visit (C-peptide6min (6month-baseline)) showed mild, negative correlation with relative size of the CD8 + CD25 + subpopulation (r = - 0.511, p = 0.025), which may indicate that the size of this cell subpopulation has predictive value in assessing future functional beta-cell changes.

Glucose intolerance and associated factors in Mongolia: results of a national survey

AIMS

Prevalence of glucose intolerance-diabetes and impaired glucose tolerance (IGT)-and of related conditions such as obesity and hypertension, was studied in six population samples in Mongolia in 1999.

METHODS

Diagnosis of glucose intolerance was made on the basis of 2-h blood glucose concentration, according to criteria recommended by the latest report of a WHO Expert Group.

RESULTS

Crude prevalence of diabetes was 2.9% (2.6% in men and 3.2% in women). Prevalence of IGT was 10.2% (9.3% in men and 10.8% in women). Age standardization to the standard world population of Segi resulted in a total sample prevalence of 3.1% for diabetes and 9.2% for IGT. Prevalence of abnormal glucose tolerance differed according to district of residence. Approximately one-third of the subjects with diabetes were diagnosed prior to the survey. Of those who were diagnosed previously, approximately one-half were not under any form of treatment. Subjects with abnormal glucose tolerance were older, more obese and had higher blood pressure and prevalence of hypertension than those with normoglycaemia. One-half of men and almost one-half of women were hypertensive. Three-quarters of the diabetic subjects were hypertensive. One-third of all subjects were centrally obese. Considering the conditions of principal interest-glucose intolerance, hypertension and obesity-one-half of all subjects demonstrated one or more of these conditions. Central obesity was the most common condition, followed by hypertension and then glucose intolerance. Central obesity and hypertension was the most common combination (17% of all subjects) and 4% exhibited all three conditions.

CONCLUSIONS

Non-communicable diseases are already a threat to public health in Mongolia. Although the prevalence of diabetes is not high by international standards, the relatively high prevalence of IGT suggests that the situation may deteriorate in the future in the absence of concerted action to prevent and control diabetes and related conditions.

Introduction of a methyl group in alpha- or beta-position of 1-heteroarylethyl-4-phenylpiperazines affects their dopaminergic/serotonergic properties

1-(2-Heteroarylalkyl)-4-phenylpiperazines containing methyl group in either the alpha- or the beta-position of the side alkyl chain were synthesized as racemic mixtures. They were evaluated for in vitro binding affinity at the D1 and D2 dopamine and 5-HT1A serotonin receptors using synaptosomal membranes of the bovine caudate nucleus and hippocampus, respectively, as a source of the corresponding receptors. Tritiated SCH 23390 (D1 receptor-selective), spiperone (D2 receptor-selective), and 8-OH-DPAT (5-HT1A receptor-selective) were employed as the radioligands. None of the new compounds expressed significant affinity for the D1 receptor. Introduction of the methyl group into the beta-position of the parent molecules increased the affinity for the D2 receptor (10b-13b), and decreased the affinity for the 5-HT1A receptor with the exception of imidazole (11b) which was a rather efficient displacer of 8-OH-DPAT. Most potent of the newly synthesized compounds in [3H]spiperone assay were compounds (+/-)6-[1-methyl-2- (4-phenylpiperazin-1-yl)-ethyl]-1,4-dihydroquinoxaline-2,3-dione (10b), Kd = 6.0 nM and (+/-)5-[1-methyl-2-(4-phenylpiperazin-1-yl)-ethyl]-1,3-dihydrobenzoimidazol- 2-thione (13b), Kd = 5.3 nM. However, compounds containing methyl group in alpha-position (10a-13a) of the parent molecules expressed a decreased affinity for the D2 receptor, while the affinity for the 5-HT1A receptor remained in the same range of concentrations as that of closely related achiral parent compounds (14-17) run in the same binding assays as references.

Prevalence and management of hypertension in type 1 diabetes mellitus in Europe: the EURODIAB IDDM Complications Study

AIM

To examine the prevalence of hypertension and the rates of hypertension awareness by investigating treatment and control among respondents to the EURODIAB IDDM Complications Study, and to explore the variation in hypertension management by age, sex and end-organ damage.

METHODS

A cross-sectional study, examining 3250 randomly selected Type 1 diabetic patients from 31 diabetes clinics in 16 European countries between 1989 and 1990. Mean age was 32.7 years (SD= 10.0) and mean duration of diabetes mellitus (DM) was 14.7 years (SD=9.3). Subjects were asked about a history of high blood pressure (BP) and current prescribed medications were recorded by the subject's physician. Hypertension was defined as having a systolic BP > or = 140 mmHg or diastolic BP > or = 90 mmHg or current use of antihypertensives. Control was defined as a BP < 130/85 mmHg.

RESULTS

Twenty-four per cent of subjects had hypertension, among whom fewer than one-half (48.5%) were aware of a previous diagnosis and a similar proportion (42.2%) were on treatment. Only 11.3% of those with hypertension were both treated and controlled. The majority (81%) of those receiving drug therapy for hypertension were on a single drug, most commonly an angiotensin-converting enzyme inhibitor (47%).

CONCLUSION

These data show the extent of undermanagement of hypertension in Type 1 DM across Europe prior to the publication of the St. Vincent Declaration and provide a useful baseline against which future improvements in the management of hypertension can be monitored.

Parental history of hypertension and parental history of diabetes and microvascular complications in insulin-dependent diabetes mellitus: the EURODIAB IDDM Complications Study

Diabetic nephropathy clusters in families, suggesting an inherited predisposition. Parental history of hypertension and of Type 2 diabetes mellitus have been associated with nephropathy in offspring with Type 1 diabetes in some studies but not in others. The associations of parental history of hypertension and of diabetes with both albuminuria and proliferative retinopathy were studied in a large cross-sectional study of 3250 patients with Type 1 diabetes, from 16 European countries. Albuminuria was associated with hypertension in a parent (p < 0.01 in men, p < 0.05 in women), adjusted for age. Patients with a parental history of hypertension had a higher prevalence of hypertension (p < 0.001 in men, p < 0.01 in women) and a higher prevalence of parental diabetes (p < 0.001 in men, p < 0.001 in women). The association of albuminuria with parental hypertension was independent of parental diabetes in men but not women (OR = 1.28 in men p = 0.04, OR = 1.25 in women p = 0.09) and was not independent of hypertension in the patient him/herself in either sex. Albuminuria was associated with parental diabetes in women only (OR = 1.36, p = 0.04). This association was independent of both parental hypertension and hypertension in the patient herself. Proliferative retinopathy was not associated with parental hypertension or diabetes. The implications of these data are that both candidate genes for hypertension and Type 2 diabetes should be considered in the search for the genetic determinants of diabetic nephropathy.

Effect of war on glycemic control in type II diabetic patients

OBJECTIVE

To determine the effect of war-related, protracted stress on glycemic control in type II diabetic patients.

RESEARCH DESIGN AND METHODS

We examined 35 patients with type II diabetes as part of their routine control in October 1990. We reexamined them in October 1991, 3 mo after the war in Croatia began. We also administered a questionnaire to assess the patients' exposure to stress and changes in diet and exercise.

RESULTS

The patients were exposed to considerable stressors. The wartime diet differed from the prewar diet. We found significant changes in total serum cholesterol and TG values (P < 0.01), but we observed no significant changes in body weight, FBG, postprandial blood glucose, and HbA1c values. Insulin and glibenclamide dosages did not change.

CONCLUSIONS

We detected no significant impact of stress on glycemic control, probably because of differences in individual stress responsiveness. Changes in the lipid status probably were attributable to changes in dietary habits caused by specific circumstances.