Diabetic control and progression of retinopathy in elderly patients: five-year follow-up study

Incidence, progression and regression of diabetic retinopathy in a northeastern Chinese population

AIM

To determine the incidence, progression and regression of diabetic retinopathy (DR), with corresponding risk factors, in a northeastern Chinese population of patients with type 2 diabetes.

METHODS

Among 2006 patients who completed baseline examinations in 2012-2013 and underwent re-examination after a mean interval of 21.2 months, 1392 patients with gradable fundus photographs for both baseline and follow-up examinations were included. Incidence was defined as new development of any DR among patients without DR at baseline. An increase of ≥2 scales (concatenating Early Treatment Diabetic Retinopathy Study levels of both eyes) in eyes with DR at baseline was defined as progression, while a reduction of ≥2 scales was defined as regression.

RESULTS

The age- and sex-standardised incidence, progression and regression were 5.8% (95% CI 4.7% to 6.9%), 26.8% (95% CI 24.8% to 28.8%) and 10.0% (95% CI 8.6% to 11.3%), respectively. In addition to poor blood glucose control, wider central retinal venular equivalent was associated with both incidence (relative risk (RR) 2.17, 95% CI 1.09 to 4.32, for ≥250 µm vs <210 µm) and progression (RR 2.00, 95% CI 1.02 to 3.96, for ≥250 µm vs <210 µm). Patients without insulin therapy (RR 0.64, 95% CI 0.43 to 0.97) and patients with wider central retinal arteriolar equivalent (RR 1.14, 95% CI 1.02 to 1.26, per 10 µm increase) were likely to exhibit DR regression.

CONCLUSION

We determined the incidence, progression and regression of DR among northeastern Chinese patients with type 2 diabetes. Retinal vessel diameters, in addition to blood glucose level, influence the natural evolution of DR.

Intensive glycemic control and macrovascular, microvascular, hypoglycemia complications and mortality in older (age ≥60years) or frail adults with type 2 diabetes: a systematic review and meta-analysis from randomized controlled trial and observation studies

INTRODUCTION

Guidelines for type 2 diabetes (T2D) recommend individualized HbA1c targets to take into account patient age or frailty. We synthesized evidence from randomized controlled trials and observational studies for intensive glycemic control (HbA1c target ≤58 mmol/mol) versus standard care, in elderly (age ≥60 years) or frail adults with T2D.

METHODS

Searches were performed utilizing recognized terms for T2D, frailty, older age, and HbA1c control and outcomes of interest. Meta-analysis was performed where possible. Primary outcomes included all-cause mortality, severe hypoglycemia, and hospital admission rates. Vascular complications, cognitive decline, and falls/fractures were secondary outcomes.

RESULTS

7,528 studies were identified of which 15 different clinical studies were selected. No difference was noted in all-cause mortality with intensive control (pooled hazard ratio 0.96, 95% confidence interval 0.90-1.03), but risk of severe hypoglycemia increased (2.45, 2.22-2.72). Intensive control was associated reductions in microvascular (0.73, 0.68-0.79) and macrovascular complications (0.84, 0.79-0.89). Outcome data for risk of hospitalization, cognition, and falls/fractures were limited.

CONCLUSION

Intensive glycemic control was associated with reduced rates of complications but increased severe hypoglycemia. Significant heterogeneity exists and the impact of different drug regimens is unclear. Caution is needed when setting glycemic targets in elderly or frail individuals.

Evidence-Based Management of Diabetes in Older Adults

The number of older adults with diabetes is rapidly increasing worldwide. A variety of factors contribute to the age-related increase in the incidence of diabetes. The lack of empiric evidence in the field has limited the management guidelines to mostly expert opinion. Given uncertainty over the rate at which to lower blood glucose levels and the optimal method of doing so, the goals of diabetes control in older people must be individualized. If the patient requires insulin therapy, the newer insulins, with their improved pharmacodynamic consistency and reduced risk of hypoglycemia, should be preferred. Several oral agents are preferable for people with sufficient endogenous insulin because they do not cause hypoglycemia when used as monotherapy. Some of these oral agents have been found to have cardioprotective effects. Older people with diabetes also require management of the other risk factors for cardiovascular disease, with antihypertensive drugs, cholesterol-lowering agents and low-dose aspirin. However, the precise targets for blood pressure control and low-density lipoprotein (LDL) cholesterol levels continue to evolve as more data become available. Diabetes care in older adults should focus on enhancing the individual's quality of life rather than trying to normalize blood glucose levels or reach predetermined blood pressure and LDL cholesterol targets.

Relationship between dyslipidemia and diabetic retinopathy: A systematic review and meta-analysis

BACKGROUND

The association between serum lipids and diabetic retinopathy (DR) was controversial. Therefore, we performed a meta-analysis to evaluate the relationship between triglycerides (TG), serum total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C), and DR.

METHODS

A systematic review and meta-analysis of observational studies was carried out to explore the association between serum lipids and DR. Studies related were initially indentified by searching PubMed, Cochrane Library, and Elsevier databases through June, 2017. Then a manual retrieval was also performed. RevMan 5.3 software was used to calculate the pooled mean differences (MDs) and related 95% confidence intervals (CIs). To test the stability of the final results, a sensitivity analysis was also performed.

RESULTS

A total of 7 studies were included in this meta-analysis. When compared with the controls, the DR cases did not show significantly higher TG levels (MD 9.18 mg/dL, 95%CI -4.14 to 22.49, P = .18), higher TC levels (MD 3.77 mg/dL, 95%CI: -2.45 to 9.98, P = .24), as well as lower HDL-C levels (MD -1.14 mg/dL, 95%CI: -2.43 to 0.15, P = .08). But slightly higher LDL-C levels were observed (MD 3.74 mg/dL, 95%CI: 0.13-7.35, P = .04). In addition, whether serum lipids involved in the progression of DR were relatively unexplored, but fenofibrate was confirmed to benefit the DR cases.

CONCLUSIONS

Based on recent published data, we did not find obvious differences in TG, TC, and HDL-C levels between patients with DR and without DR. However, slightly higher LDL-C levels were observed in the DR cases.

Prevalence of diabetic retinopathy in various ethnic groups: a worldwide perspective

The alarming rise in diabetes prevalence is a global public health and economic problem. Diabetic retinopathy is the most common complication of diabetes and the leading cause of blindness among working-age populations in the Western world. Screening and prompt treatment of diabetic retinopathy are not top priorities in many regions of the world, because the impacts of other causes of preventable blindness remain an issue. Ethnicity is a complex, independent risk factor for diabetic retinopathy. Observations from white populations cannot be extrapolated fully to other ethnic groups. The prevalence of diabetic retinopathy, sight-threatening diabetic retinopathy, and clinically significant macular edema are higher in people of South Asian, African, Latin American, and indigenous tribal descent compared to the white population. Although all ethnic groups are susceptible to the established risk factors of diabetic retinopathy-such as length of exposure and severity of hyperglycemia, hypertension, and hyperlipidemia-ethnic-specific risk factors also may influence these rates. Such risk factors may include differential susceptibility to conventional risk factors, insulin resistance, differences in anthropometric measurements, truncal obesity, urbanization, variations in access to healthcare systems, genetic susceptibility, and epigenetics. The rates of nonproliferative diabetic retinopathy appear to be declining in the United States, supporting the observation that better medical management of diabetes and prompt treatment of sight-threatening diabetic retinopathy substantially improve the long-term diabetic retinopathy incidence; studies from other parts of the world are limited and do not mirror this finding, however. We examine the ethnicity and region-based prevalence of diabetic retinopathy around the world and highlight the need to reinforce ethnicity-based screening and treatment thresholds in diabetic retinopathy.

Optimal glycemic control in the elderly: where is the evidence and who should be targeted?

In the near future, with the continuous increase in life expectancy observed in the population and with the aging of the baby boomers, an increase is expected in the absolute and relative number of the elderly population. With the aging phenomenon, the prevalence of a number of chronic diseases is increasing and requires interventions from different health professionals. Type 2 diabetes mellitus is a very frequent condition in the elderly and is characterized by variable degrees of hyperglycemia while ketosis is exceptional in this condition. The question of who should be offered optimal glycemic control becomes more and more pertinent as the older diabetic population grows but it has to be considered that the consequences of hypoglycemia related to the medications used to lower glycemia are not benign in the older population. Hence, the advantages and disadvantages of tight glycemic control will be reviewed in the light of recent data.

Relationship between glycemic control and depression among American Indians in the Strong Heart Study

OBJECTIVES

To examine the relationship between depression and glycemic control in the Strong Heart Study (SHS), a longitudinal study of cardiovascular disease in American Indians.

METHODS

This cross-sectional analysis focused on the relationship between depression, diabetes and glycemic control among 2832 individuals aged > or =15 years. Depression was measured by the Center for Epidemiologic Studies of Depression Scale and diabetes by American Diabetes Association criteria. An ordered logit regression model was used to assess whether diabetes was related to level of depression (none, mild, moderate, severe). Multiple logistic regression was used to explore the relationship between A1c and severe depression in participants with diabetes.

RESULTS

Rates of depression were higher in men and women with diabetes when compared to those without diabetes, respectively (P<.05). For every 1-U increase in A1c, the odds of severe depression increased by 22% (OR 1.22, 95% CI: 1.05-1.42). Female sex (OR 2.97, 95% CI: 1.32-6.69) and body mass index (BMI) (OR 1.04, 95% CI: 1.00-1.08) also were significantly associated with increased risk for severe depression. Although BMI appears to be significantly associated with increased risk for severe depression, the magnitude of this effect was small.

CONCLUSIONS

Individuals with diabetes have higher rates of depression than those without diabetes, consistent with other populations. There is a positive relationship between severity of depression and A1c levels; men and women with severe depression have higher A1c levels than those with moderate-to-no depression.

Evaluation of adverse events of oral antihyperglycemic monotherapy experienced by a geriatric population in a real-world setting: a retrospective cohort analysis

BACKGROUND AND OBJECTIVE

To evaluate and compare the risk of adverse events (AEs) associated with the use of metformin, sulfonylureas and thiazolidinediones among geriatric patients in a usual care setting.

METHODS

An electronic medical record database was utilized to identify geriatric patients with type 2 diabetes mellitus aged > or =65 years from 1996 to 2005. Patients naive to oral antihyperglycemic drug (OAD) therapy were followed for 395 days post initiation of metformin, sulfonylurea or thiazolidinedione treatment. AEs related to study drugs were evaluated during the follow-up period, and the risks of developing an AE were evaluated and adjusted for differences in baseline characteristics by OAD treatment.

RESULTS

A total of 5438 patients (mean age 73.2 [SD 5.08] years, 56.1% female) were identified. During the follow-up period, 12.5% of patients experienced an AE (8.3% of metformin, 13.9% of sulfonylurea and 19.8% of thiazolidinedione recipients). Sulfonylurea (odds ratio [OR] 1.74; 95% CI 1.41, 2.13) and thiazolidinedione (OR 2.86; 95% CI 2.23, 3.65) recipients were more likely to experience an AE than metformin recipients, after adjustment for baseline demographic and co-morbidity differences. The average time to onset of a metformin AE (175 days) was less than that for sulfonylurea or thiazolidinedione treatment (192 and 201 days, respectively). The most common AEs were abdominal pain with metformin (42.3%) and weight gain >4.5 kg for sulfonylureas (63.2%) and thiazolidinediones (68.2%). Hypoglycaemia occurred in 2.6% and 2.2% of sulfonylurea and thiazolidinedione recipients, respectively.

DISCUSSION AND CONCLUSIONS

Geriatric patients in a real-world setting experienced AEs with metformin, sulfonylurea and thiazolidinedione therapy, although rates differed from those seen in clinical trials, particularly for weight gain and hypoglycaemia. Lactic acidosis occurred at a higher rate with metformin therapy than has been reported in clinical trials, but our results were in the same range for abdominal pain and lower for diarrhoea, nausea/vomiting and dyspepsia. AEs related to sulfonylurea therapy were in the same range as in clinical trials for weight gain but lower for hypoglycaemia, dizziness and headaches. AEs related to thiazolidinedione therapy were more common in our study than in clinical trials, and within the same range for weight gain and elevated liver enzymes but lower for hypoglycaemia and oedema. While AE reporting is likely to be different in a real-world setting than in clinical trials, the observed variances may also be due to the aetiology of diabetes and the physiological response to hypoglycaemia in an older population.

Diabetes and aging: epidemiologic overview

Diabetes mellitus has long been recognized as a cause of accelerated aging. As the understanding of the metabolic syndrome has evolved, it has been recognized that the interaction of a panoply of factors in the presence of insulin resistance results in accelerated aging. This article explores the increasing prevalence of diabetes mellitus with aging and how insulin resistance leads to accelerated frailty, disability, hospitalization, institutionalization, and death.

Five-year incidence and progression of diabetic retinopathy in a defined older population: the Blue Mountains Eye Study

AIMS

To determine 5-year incidence and progression of diabetic retinopathy in an older Australian population-based cohort.

METHODS

During the period 1992-1994, the Blue Mountains Eye Study examined 3654 residents aged 49+years (82.4% of those eligible), living in two urban postcode areas, west of Sydney, Australia. Participants were subsequently invited to attend 5-year follow-up exams. After excluding 543 (14.8%) who died during the follow-up period, 2334 persons (75.0%) were re-examined during 1997-1999. The examination included a comprehensive questionnaire, blood pressure measurement, standardised refraction, Zeiss stereo retinal photographs, and estimation of fasting blood glucose. Diabetic retinopathy was graded from the retinal photographs, using the modified Early Treatment Diabetic Retinopathy Scale classification (15-step scale).

RESULTS

Of participants with diabetes diagnosed at baseline, 150 were re-examined, including 139 with gradable fundus photographs. The cumulative 5-year incidence of diabetic retinopathy was 22.2% before 95% confidence interval (CI) 14.1-32.2%. Retinopathy progression (1+ steps) was documented in 25.9% (95% CI 18.8-34.0%) of participants with retinopathy and gradable photographs at both visits; in 58.3% of these cases, a 2+ -step progression was documented. Progression to proliferative retinopathy occurred in only 4.1% of those with retinopathy at baseline. The only baseline risk factors associated with retinopathy progression, after adjusting for age and gender, were increase in fasting blood glucose, odds ratio (OR) 1.2 (95% CI 1.1-1.4)/mmol/l, and increase in diabetes duration, OR 2.3 (95% CI 1.0-5.3)/10 years.

CONCLUSIONS

These data provide 5-year cumulative incidence of diabetic retinopathy in a defined older population. Increase in diabetes duration and elevated baseline fasting blood glucose level predicted retinopathy incidence.

The role of alexithymia factors in glucose control of persons with type 1 diabetes: a pilot study

OBJECTIVE

To clarify the respective contribution of demographic characteristics, health conditions and three psychological variables (depression, anxiety, alexithymia) for glycaemic control measured by glycated hemoglobin (HbA1c).

MATERIALS AND METHODS

Sixty-four persons diagnosed with type 1 diabetes completed psychological measures and demographic information at admission (T1) to the hospital and in a follow-up (+8 weeks) (T2). Additional information about their health conditions was also considered.

RESULTS

At T1, the alexithymia factor "difficulties describing feelings" (DDF) predicted HbA1c over and above the predictive power of demographic information, health conditions, anxiety, and depression. Additionally, higher decrease in HbA1c from T1 to T2 was predicted by higher scores on the alexithymia factor DDF at admission over and above the other predictors.

CONCLUSION

DDF is an important predictor of glucose control. Scoring higher on this factor is related to poorer glycaemic control at admission. Additionally, people with higher scores on this factor seem to benefit highly from the treatment administered at the hospital.

Population-Based Study of Nonproliferative Diabetic Retinopathy Among Type 2 Diabetic Patients in Kinmen, Taiwan

PURPOSE

This study was conducted to assess the prevalence and associated factors of nonproliferative diabetic retinopathy among type 2 diabetic patients in Kinmen, Taiwan.

METHODS

From 1991 to 1993, 971 type 2 diabetic patients in Kinmen underwent diabetic retinopathy screening performed by a panel of ophthalmologists using indirect ophthalmoscopy and 45 degrees color fundus retinal photographs.

RESULTS

Of the 971 patients screened in 1991-1993, 578 (59.5%) were examined for this study. Diabetic retinopathy was diagnosed in 127 patients (22.0%), including nonproliferative diabetic retinopathy in 13.3%, proliferative diabetic retinopathy in 1.4%, legal blindness in 1.4%, and ungradable diabetic retinopathy in 5.9%. Significant associated factors of nonproliferative diabetic retinopathy based on multiple logistic regression analysis were fasting plasma glucose (FPG) at baseline [> or =126 mg/dl vs. <126 mg/dl; odds ratio (OR) = 2.89; 95% confidence interval (CI), 1.01-9.09], 2-h postload at baseline (> or =200 vs. <200 mg/dl; OR = 1.48; 95% CI, 1.09-2.07); HbA1c at follow-up (> or =7% vs. <7%; OR = 6.54; 95% CI, 3.01-14.20), duration of diabetes (> or =15 years vs. <10 years; OR = 6.72; 95% CI, 2.13-21.18), and incremental systolic blood pressure between baseline and follow-up (OR = 1.02; 95% CI, 1.00-1.04).

CONCLUSIONS

In addition to the longer duration of type 2 diabetes, FPG at baseline, poorly controlled glucose concentration, and altered blood pressure may increase the risk of nonproliferative diabetic retinopathy in type 2 diabetic patients.

Depression and coronary heart disease in women with diabetes

OBJECTIVE

The protective effects of female gender on the appearance and course of coronary heart disease (CHD) in nondiabetic subjects are diminished in the presence of diabetes. Depression predicts onset of and poor outcome from CHD in nondiabetic populations. We hypothesized that the doubled rates of depression in female diabetic patients could help explain the high prevalence of CHD in women with diabetes.

METHOD

Seventy-six female type 1 and type 2 diabetic patients with (N=16) or without (N=60) active major depression (DSM-III) at index evaluation underwent systematic annual investigation of diabetes and its complications for up to 10 years. Occurrences of CHD and other macrovascular complications were examined in relation to depression status using survival analysis statistics. A multivariate model incorporating other CHD risk factors (age, duration of diabetes, body mass index, glycosylated hemoglobin, and presence of hypertension, hyperlipidemia, or tobacco use) was used to determine independent effects of depression on outcome.

RESULTS

Development of CHD was significantly more rapid in the depressed subset (p<0.01 between 10-year curves), an effect that persisted after controlling for base-line differences in body mass index. Depression also was retained as an independent predictor of CHD in the multivariate model with an age-adjusted hazard ratio of 5.2 (95% CI: 1.4-18.9; p=.01). In contrast, depression did not predict the development of clinically apparent peripheral or cerebrovascular disease.

CONCLUSIONS

In this sample of diabetic women, major depression was an independent risk factor that accelerated the development of CHD. Depression recognition and management may improve outcomes from diabetes in this gender subgroup.

Anxiety and poor glycemic control: a meta-analytic review of the literature

OBJECTIVE

To determine whether anxiety is associated with poor glycemic control in adults with type 1 or type 2 diabetes.

METHOD

MEDLINE, PubMed, and PsycINFO databases were used to locate studies that measured the association of anxiety with glycemic control. Meta-analytic procedures were used to convert the findings to a common metric, compute effect sizes (ES), and statistically analyze the collective data.

RESULTS

The search procedures identified 12 studies, 11 (92 percent) of which satisfied the criteria for inclusion in the meta-analysis. In this overall group, anxiety was not associated with glycemic control (p = 0.19), although the ES was marginally statistically significant (ES = .09, 95 percent CI = 0.04 to 0.14). In studies that determined anxiety from diagnostic interviews, anxiety was associated with hyperglycemia (p = 0.003) and the ES was also statistically significant (ES: 0.25, 95 percent CI = 0.10 to 0.38).

CONCLUSIONS

The existing literature suggests that anxiety disorders are associated with hyperglycemia in diabetic patients. Additional studies are required to confirm the magnitude of the relationship, to elucidate moderating and causal factors, and to determine whether successful treatment of anxiety improves glycemic control.

Prospective analysis of mortality, morbidity, and risk factors in elderly diabetic subjects: Nagano study

OBJECTIVE

To clarify mortality and morbidity of intensively managed elderly diabetic individuals and to explore factors predicting mortality and diabetes-related end points.

RESEARCH DESIGN AND METHODS

A total of 390 elderly (>or=65 years of age) outpatients with type 2 diabetes ( 173 men and 217 women, mean age 73.0 years) were analyzed. The mean HbA(1c) upon entry was 6.8% (332 receiving oral hypoglycemics and/or insulin) and blood pressure upon entry was 136/74 mmHg (219 receiving antihypertensive drugs). The patients have been followed-up for 3 years with HbA(1c) <7.0% and blood pressure <145/80 mmHg as targets, with mortality and an aggregate of fatal and nonfatal diabetes-related events as end points. Mortality rate and causes of mortality, as well as risk factors for mortality and morbidity, were determined.

RESULTS

The mortality rate, 2.9% per year, was comparable to that of the age- and sex-matched general population. Stroke was a leading cause of mortality after malignancy. By the univariate Cox proportional hazards model, only high serum creatinine and prior stroke were highly significant and strong risks for both end points. In those without prior stroke and receiving antihypertensive agents, the incidence of the diabetes-related end point based on their systolic blood pressure (SBP) quartile was U-shaped, with the nadir at the 3rd (SBP, 137-147 mmHg) and the peak at the 1st (SBP <or= 125 mmHg) quartile.

CONCLUSIONS

In well-controlled elderly diabetic subjects, there was no excessive mortality compared to the age- and sex-matched general population. Renal dysfunction and prior stroke were independent risks for mortality and morbidity. In those without prior stroke, a risk of too much lowering of blood pressure was suggested.

Treatment of depression in diabetes: impact on mood and medical outcome

Depression is prevalent as a co-morbid condition in diabetes. The efficacy of depression treatment with either pharmacological agents or psychotherapy has been demonstrated in the few available controlled trials. Depression has been associated with poor glycemic control and with accelerated rates of coronary heart disease in diabetic patients. Reported depression treatment trials demonstrate benefits of depression remission on glycemic control as well as mood and the potential for improvement in the course and outcome of diabetes. Because adverse effects of pharmacological agents on glycemic control have been observed, optimal therapies that improve both depression and measures of diabetes are still being sought. This review critically examines the efficacy of depression treatment in diabetes patients, the effects of depression treatment on the medical condition, and methodological issues important in the performance of treatment trials in the patient population.

Tablet-breaking ability of older persons with type 2 diabetes mellitus

PURPOSE

The purpose of this study was to assess the ability of older persons with type 2 diabetes to accurately break in half 2 different formulations of micronized glyburide tablets.

METHODS

Thirty persons with type 2 diabetes, over age 70, were recruited from the St Louis University geriatric clinics. Participants were randomly assigned to 2 groups. Group A broke 30 Glynase Prestabs and 30 generic tablets using 2 different manual tablet-breaking methods. Group B broke 15 Glynase Prestabs and 15 generic tablets without instructions. Visual analog scales were used to assess pain and difficulty of tablet breaking.

RESULTS

A higher percentage of successful tablet breaking was reported with Glynase Prestabs (80%) compared with the generic tablets (33%). Mean pain scores for breaking Glynase Prestabs were 0.1 (Group A) and 0.9 (Group B). Higher pain scores were obtained for the generic tablets (2.1 for Group A, 3.2 for Group B). Glynase Prestabs were easier to break in both groups, and the resultant half tablets showed less variance from the expected theoretical weight (50% of whole parent tablet weight).

CONCLUSIONS

Older adults broke Glynase Prestabs more accurately and with less difficulty than generic micronized glyburide tablets. This variation in ease of tablet breaking and accuracy between different tablet formulations affect bioavailability and patient compliance.

Variations in the care of elderly persons with diabetes among endocrinologists, general internists, and geriatricians

BACKGROUND

The American Diabetes Association (ADA) clinical practice recommendations have been widely promoted, but they lack a geriatric-specific approach to care. We aimed to determine the style of care that endocrinologists, general internists, and geriatricians provided to their elderly patients with diabetes and to what extent these medical professionals adhered to the ADA standards.

METHODS

We performed a retrospective cohort study of a stratified sample of 531 diabetic patients aged 65 years and older from the endocrinology, general internal medicine, and geriatrics clinics of an urban academic medical center.

RESULTS

Patients of geriatricians were older, had higher comorbidity, and were more likely to be demented. The average number of diabetic complications was similar across the specialties, although patients of endocrinologists had higher prevalence of neuropathy and retinopathy compared with patients of geriatricians. Endocrinologists were more likely to use insulin, multiple types of insulin, and combined oral hypoglycemic and insulin therapies. Most patients had hemoglobin A1c measured, and average values were similarly high across specialties at 8.6%. Blood pressures were above 130/85 mm Hg in 85% of the patients. All specialties rarely measured urine microalbumin; geriatricians seldom performed fractionated cholesterol tests, and ophthalmology visits occurred in only half of the patients.

CONCLUSION

Endocrinologists had the most aggressive, complex diabetes treatment regimens, although geriatricians had older patients with more dementia and lower prevalence of microvascular complications. Average hemoglobin A1c levels and blood pressures were higher than recommended among patients of all three specialties. Screening for diabetic complications and hyperlipidemia was lower than advised.

Early macular dysfunction detected by focal electroretinographic recording in non-insulin-dependent diabetics without retinopathy

The focal electroretinogram, which measures the functional integrity of the distal retina of the macula, was recorded with a hand-held stimulator-ophthalmoscope in 26 eyes from patients with non-insulin-dependent diabetes mellitus with normal fundus photography, and in 52 control eyes of similar age range. Implicit time and amplitude of the responses were studied as a function of the age, glycemic control through glycosylated hemoglobin measurement and duration of diabetes. Implicit time and amplitude were significantly delayed (F=5.05, p=0.028) and reduced (F=11.26, p=0.013) in diabetic patients without diabetic retinopathy compared to control subjects. Moreover, there was a significant relationship between the implicit time (r=0.57, p=0.002) and amplitude (r=-0.65, p=0.0004) with the duration of diabetes but not with hemoglobin Alc. These results strongly suggest an early macular dysfunction in non-insulin-dependent diabetes mellitus before the appearance of diabetic retinopathy.

Diabetes mellitus in older persons

The relative importance and mechanisms of deficient insulin secretion versus deficient action during aging are still debated. Whatever mechanisms eventually explain the emergence of impaired glucose tolerance during aging, the clinically important extrinsic modifiers of glycemic levels include diet, medications, activity, and chronic illness and stress. Although prospective studies are not available in the elderly, retrospective studies suggest that good blood glucose control reduces the likelihood and severity of stroke, cardiovascular disease, visual impairment, nephropathy, infections, and even cognitive dysfunction. Good control also seems to reduce nocturia, polyuria, and hypovolemia. Therapy of older persons begins with diet, exercise, and oral agents, failing which, insulin is employed. Since many of the newer oral agents carry less risk of hypoglycemia, achieving tighter control in the elderly has become more feasible.

Importance of glucose control

The importance of glycemic control in reducing the microvascular complications of type 1 diabetes has been clearly demonstrated with a long-term prospective, randomized interventional trial. The data are not as strong with regards to type 2 diabetes. The results of several prospective studies and one interventional study, however, all report benefits of improved glycemic indices on reducing microvascular complications. The available literature evaluating the relationship between glycemic control and macrovascular disease in type 1 and type 2 diabetes demonstrates the importance of glucose control. One could make rational scientific arguments or criticize the design and interpretations of any one individual study. Yet collectively the evidence is powerful. Additionally, there have been no negative studies reported. Lowering the glycosylated hemoglobin to less than 2 percentage points above the upper limit of normal should be the first glycemic goal for most patients with diabetes. Obviously, some patients cannot obtain this degree of control for a variety of reasons. Moreover, the intensity of therapy needs to be individualized and tailored to each patient. In addition, intensive glycemic control does not necessarily mean multiple injections or insulin pumps or home glucose monitoring 10 times a day. Intensive glycemic control means that the glycohemoglobin (hemoglobin and A1C and blood glucose values are in a normal or near-normal range, no matter how simple or how complex the treatment regimen. The most controversial issue is with regards to the relationship between hyperinsulinemia and accelerated atherosclerosis. This association is not consistently found in many of the large prospective studies, and certainly there has never been a direct cause-and-effect relationship proven. Most experts in the field recommend that insulin be reserved for patients with type II diabetes when oral therapy cannot achieve near-normal glycemic control. Weight gain and hypoglycemia are adverse effects of sulfonylurea and insulin therapy. These adverse effects are dwarfed, however, by the acute and chronic complications of poorly controlled diabetes. Lastly, estimates on the economic benefits of reducing long-term microvascular and macrovascular complications in populations are staggering. Based on the available literature, all patients with diabetes should be educated and have access to an appropriate individualized treatment regimen with the goal to normalize or near-normalize glycemic control. This should be the standard of care until proven otherwise.

Clinical and biochemical outcomes of type 2 diabetes mellitus in Canterbury, New Zealand: a 6-year cohort study

There is a paucity of data regarding outcomes of Type 2 diabetes mellitus. A cohort of 447 Type 2 diabetic subjects (208 male, 239 female; age range 30-82 years, median 62 years; and of predominantly European origin) was characterised in a clinic survey in 1989. Individual status (dead or alive) at 1 June 1995 was ascertained. At 6 years, 289 subjects were confirmed as alive and 133 as dead--only 25 were untraceable. Of those subjects identified as alive, follow-up clinical and biochemical data were obtained for 253 (87.5%) individuals. In those subjects, glycated haemoglobin deteriorated from 63.1 +/- 18.7 mmol/mol haem in 1989 to 71.7 +/- 24.4 in 1995, P < 0.0001. An increased prevalence of retinopathy was evident at 6-year follow-up, 59.7% cases in 1995 compared with 39.5% in 1989, P < 0.001. Similarly there was an increased prevalence of coronary artery disease (CAD) (33.6 vs 18.2% of cases), albuminuria (26.5 vs 19% of cases; P < 0.001), and hypertension (71.5 vs 54.9% of cases; P < 0.001) in 1995 vs 1989, respectively. Multiple logistic regression analysis showed that glycated haemoglobin (odds ratio (OR) for 18 mmol/mol haem change, 1.78; 95% CI, 1.15-2.85), hypertension (OR, 3.33; 95% CI, 1.40-8.41) and known duration of diabetes (OR for 7 year change, 2.12; 95% CI, 1.24-3.80) were predictors for development of retinopathy. There is therefore a deterioration in glycaemic control in Type 2 diabetes over 6 years and an increased prevalence of complications that present strategies in a multidisciplinary specialist diabetes clinic are unable to prevent on a sustainable basis.

Importance of Control in Type II Diabetes Mellitus

OBJECTIVE

To determine the effect of maintenance of control of type II diabetes mellitus on the occurrence of complications.

METHODS

Various published studies of populations of patients with diabetes are reviewed, and their results in terms of diabetic control and development of retinopathy, nephropathy, neuropathy, and macrovascular disease are summarized.

RESULTS

Maintenance of near-euglycemia reduced the risk of worsening diabetic retinopathy; proliferative retinopathy developed in few patients with well-controlled diabetes. Similarly, worsening proteinuria was more common in patients with fair and poor control of diabetes in comparison with those who were able to maintain good control of diabetes. Furthermore, patients with poor diabetic control experienced a faster deterioration of peripheral neurologic function than did the patients with well-controlled diabetes. In five prospective studies of a total of 2,471 patients with type II diabetes, stricter control of diabetes was associated with fewer cardiovascular events and deaths.

CONCLUSION

Overwhelming evidence from published prospective studies indicates that the complications often associated with type II diabetes can be minimized or delayed by maintaining good control of the disease.

Effects of nortriptyline on depression and glycemic control in diabetes: results of a double-blind, placebo-controlled trial

OBJECTIVE

Depression is a prevalent and chronic condition in diabetes and is associated with poor glucose regulation and poor compliance with diabetes treatment. This investigation evaluated the effects of nortriptyline on depression and glycemic control to see whether depression in diabetes is treatable and whether restoring mental health contributes to improved medical outcome.

METHOD

Sixty-eight diabetic patients with poor glycemic control, 28 of whom had active major depression (DSM-IIIR), completed a randomized, placebo-controlled, double-blind trial involving 8 weeks of treatment with nortriptyline targeted to therapeutic plasma levels (50-150 ng/ml). Depression improvement was determined with the Beck Depression Inventory; glucose control was measured by glycated hemoglobin levels. Compliance behavior was assessed using medication dispensing devices and glucometers equipped with electronic memory.

RESULTS

The reduction in depression symptoms was significantly greater in depressed patients treated with nortriptyline compared with those receiving placebo (-10.2 vs -5.8, p = .03). Nortriptyline was not statistically superior to placebo in reducing glycated hemoglobin of the depressed subjects (p = .5). However, path analysis indicated that the direct effect of nortriptyline was to worsen glycemic control whereas depression improvement had an independent beneficial effect on glycated hemoglobin. These findings were not explained by the relationships of nortriptyline treatment to weight change (r = -0.21, p = .31) or depression improvement to compliance with the protocol for self-monitoring of blood glucose (r = 0.01, p = .97).

CONCLUSIONS

Major depression in diabetic patients can be effectively treated with nortriptyline at the expense of a direct hyperglycemic effect. Path analysis demonstrated a treatment-independent effect of depression improvement on glycemic control, suggesting that a more ideal antidepressant agent may both restore mental health and improve medical outcome.

Diabetes in the elderly

Diabetes affects at least 20% of the population over the age of 65. Half of these patients are unaware that they have the disease. Diabetes in middle-aged subjects is characterized by an impairment in glucose induced insulin release, increased fasting hepatic glucose output and resistance to insulin mediated glucose disposal. In contrast, diabetes in the elderly is primarily associated with insulin deficiency. The presentation of diabetes in the aged is often non-specific. The elderly have an increased frequency of complications from diabetes. They are particularly susceptible to hypoglycaemia, because of reduced awareness of hypoglycaemic warning symptoms and altered release of counterregulatory hormones. Although no data are yet available from randomized controlled trials, there is abundant epidemiological evidence to suggest that adequate control of blood glucose can be expected to reduce the risk of long-term complications. A team approach is ideal for the management of the elderly patient with diabetes. Little data is available on which to base a diet and exercise prescription for elderly patients. Gliclazide appears to be the sulphonylurea of choice in the aged because it is associated with a lower frequency of hypoglycaemic reactions. Urine glucose testing is unreliable, and capillary glucose monitoring is preferred. Fructosamine may prove to be superior to haemoglobin A1C for monitoring long-term control.

Lipoprotein(a) is a risk factor for diabetic retinopathy in the elderly

OBJECTIVE

To assess whether serum lipoprotein(a) is a risk factor for diabetic retinopathy in the elderly.

DESIGN

A cross-sectional study.

SETTING

Outpatient diabetic clinic.

PATIENTS

One hundred four noninsulin-dependent diabetic patients (35 males, 69 females). Twenty-three were less than 60 years of age (middle-aged), and 81 were 60 years or older (elderly).

MEASUREMENT

Levels of lipoprotein(a) (Lp(a)) and lipids were measured in fasting serum. HbA1c was also measured as an indicator of diabetic control. Other indicators possibly related to retinopathy were also checked. Retinopathy was estimated by photographs of fundi.

RESULTS

Significantly higher indicators in the group with retinopathy than in the group without were: HbA1c, Lp(a), duration of diabetes, and systolic blood pressure (BP) in the total cases; HbA1c, duration of diabetes, and Lp(a) in the middle-aged; HbA1c, systolic BP, and Lp(a) in the elderly. Multiple logistic regression analysis showed that only HbA1c and Lp(a) were independent risk factors for retinopathy in all cases and in the elderly. The incidence of retinopathy was positively correlated to serum Lp(a) levels.

CONCLUSION

Lp(a) is an independent risk factor for diabetic retinopathy.