Is obesity related to microvascular and macrovascular complications in diabetes? The Wisconsin Epidemiologic Study of Diabetic Retinopathy

BACKGROUND

There are few epidemiological data describing the relationship of obesity to the incidence of microvascular and macrovascular complications in patients with diabetes.

METHODS

In a population-based study performed in southern Wisconsin, 1370 persons diagnosed as having diabetes when they were 30 years of age or older (mean[+/- SD] age, 66.6 +/- 11.3 years) participated in a baseline examination, 987 in a 4-year follow-up examination, and 533 in a 10-year follow-up examination. Height and weight were measured using standard protocols. Individuals were characterized as underweight, normal weight, overweight, and obese by body mass index (expressed as weight in kilograms divided by the square of the height in meters) status. Outcomes included incidence and progression of retinopathy, incidence of gross proteinuria, incidence of lower-extremity amputation, and death due to ischemic heart disease, death due to stroke, and all-cause mortality.

RESULTS

The prevalence of being obese was 25.2%. After other risk factors were controlled for, being underweight was associated with higher incidence of diabetic retinopathy, death from stroke, and all-cause mortality. Body mass was not associated with progression of retinopathy, incidence of gross proteinuria, amputation of a lower extremity, or death due to ischemic heart disease.

CONCLUSIONS

These data suggest that obesity in persons with older-onset diabetes is not related to the long-term incidence of microvascular and macrovascular complications.

Risk of hypoglycemia in users of human insulin. The Wisconsin Epidemiologic study of Diabetic Retinopathy

OBJECTIVE

To evaluate whether there has been a change in frequency of hypoglycemic reactions associated with use of insulin of animal or human type.

RESEARCH DESIGN AND METHODS

Data are from a longitudinal population-based study of people with diabetes onset before 30 years of age who were receiving primary care in an 11-county area of south central Wisconsin in 1980. Interviews of study participants were conducted regarding occurrence of hypoglycemic reactions and the frequency, dose, and type of insulin used. At the 4-year follow-up, 727 of the 765 subjects were using only animal insulin and 33 were using human insulin; by the 10-year follow-up, 352 were using animal insulin and 388 were using human insulin.

RESULTS

Those using animal insulin reported fewer hypoglycemic reactions than did users of human insulin (chi (1)2 = 4.66, P = 0.03). Those who changed insulin type between visits were no more likely to report more hypoglycemic reactions during the year before the visit than those who remained on the same type at the two examinations (chi (4)2 = 3.37, P = 0.50). At the 10-year exam, users of human insulin were more likely to be taking multiple doses of insulin (86.6%) than were users of animal insulin (73.9%; P < 0.0001). In multiple logistic regression, the following variables were significantly related to the frequency of hypoglycemic reactions at the 10-year visit: body mass index (lower), glycosylated hemoglobin (lower), and being female.

CONCLUSIONS

In this population, level of glycemia is related to the frequency of hypoglycemic reactions. While type of insulin (human vs. animal) may be related to glycemia, it appears to have little independent effect on the frequency of reactions.

Cardiovascular disease, selected cardiovascular disease risk factors, and age-related cataracts: the Beaver Dam Eye Study

PURPOSE

To examine the associations of cardiovascular disease and selected cardiovascular disease risk factors with the prevalence of age-related cataract.

METHODS

We conducted a population-based prevalence study of adults aged 43 to 86 years (n = 4,926) in Beaver Dam, Wisconsin. An ocular examination including lens photographs, medical history, height and weight measurement, blood testing, and photograph grading was performed according to standard protocols.

RESULTS

Age and sex influenced most of the relationships between risk variables and cataract. Many relationships apparent in univariate analyses were not significant when controlling for confounders. In multivariate models, higher glycated hemoglobin was significantly and consistently associated with increased risk of nuclear cataract in women. For cortical cataract, higher serum high density lipoprotein cholesterol was associated with decreased risk in women. For posterior subcapsular cataract, men with higher ratios of total to high-density lipoprotein cholesterol were at increased risk. History of cardiovascular disease was not associated with cataracts in persons with or without diabetes after controlling for additional risk indicators.

CONCLUSIONS

Some risk factors for cardiovascular disease were associated with increased frequency of age-related lens opacities. Age and sex influenced these relationships but did not entirely explain them. Longitudinal follow-up is necessary to determine antecedent-consequent relationships that may suggest causal associations.

The relation of systemic hypertension to changes in the retinal vasculature: the Beaver Dam Eye Study

BACKGROUND PURPOSE

The objective was to investigate the relationship of systemic hypertension to the incidence of various retinal vascular lesions in the population-based Beaver Dam Eye Study.

METHODS

Subjects aged 43 through 86 years who lived in Beaver Dam, Wisconsin between 1987 and 1988 were examined between 1988 and 1990 and 5 years later, 1993-1995. Blood pressure was measured using standardized protocols. Stereoscopic color fundus photographs were graded in a masked fashion using standardized protocols to determine the presence of retinopathy (blot hemorrhages, microaneurysms, hard and soft exudates, intraretinal microvascular abnormalities, and venous beading), retinal arteriolar narrowing, and arterio-venous nicking. People with diabetes or retinal vascular occlusions were excluded from the analyses.

RESULTS

Among those examined, 2,151 (69.1%) were normotensive and 963 (30.9%) were hypertensive at baseline. Over the five-year period, retinopathy developed in 175 (6.0%), arteriolar narrowing in 282 (9.9%) and arterio-venous nicking in 201 (6.5%) nondiabetic subjects. After adjusting for age, hypertension was associated with the incidence of retinopathy (in men: relative risk [RR] 2.31, 95% confidence interval [CI] 1.54 to 3.48; in women: RR 1.61, 95% CI 1.07 to 2.43) and with arteriolar narrowing (in men: RR 1.82, 95% CI 1.25 to 2.66; in women: RR 1.36, 95% CI 1.05 to 1.77), but not with arterio-venous nicking (in men: RR 1.01, 95% CI 0.69 to 1.48; in women: RR 1.37, 95% CI 0.95 to 1.97). The five-year incidence of retinopathy and of arteriolar narrowing was higher in those subjects whose blood pressure was elevated despite use of antihypertensive medications compared with those subjects whose blood pressure was controlled with antihypertensive medications or those who were normotensive.

CONCLUSIONS

These data show a relation of hypertension to an increased incidence of retinopathy and arteriolar narrowing. Furthermore, these data suggest that pharmacologic control of blood pressure is related to a lower incidence of these anatomic retinal lesions relative to uncontrolled blood pressure.

Predicting Quality of Well-being scores from the SF-36: results from the Beaver Dam Health Outcomes Study

BACKGROUND

The SF-36 and the Quality of Well-being index (QWB) both quantify health status, yet have very different methodologic etiologies. The authors sought to develop an empirical equation allowing prediction of the QWB from the SF-36.

DATA

They used empirical observations of SF-36 profiles and QWB scores collected in interviews of 1,430 persons during the Beaver Dam Health Outcomes Study, a community-based population study of health status, and 57 persons from a renal dialysis clinic.

METHOD

The eight scales of the SF-36, their squares, and all pairwise cross-products, were used as candidate variables in stepwise and best-subsets regressions to predict QWB scores using 1,356 interviews reported in a previous paper. The resulting equation was cross-validated on the remaining 74 cases and using the renal dialysis patients.

RESULTS

A six-variable regression equation drawing on five of the SF-36 components predicted 56.9% of the observed QWB variance. The equation achieved an R2 of 49.5% on cross-validation using Beaver Dam participants and an R2 of 58.7% with the renal dialysis patients. An approximation for computing confidence intervals for predicted QWB mean scores is given.

CONCLUSION

SF-36 data may be used to predict mean QWB scores for groups of patients, and thus may be useful to modelers who are secondary users of health status profile data. The equation may also be used to provide an overall health utility summary score to represent SF-36 profile data so long as the profiles are not severely limited by floor or ceiling effects of the SF-36 scales. The results of this study provide a quantitative link between two important measures of health status.

The five-year incidence and progression of age-related maculopathy: the Beaver Dam Eye Study

PURPOSE

The aim of the study was to describe the incidence and progression of retinal drusen, retinal pigmentary abnormalities, and signs of late age-related maculopathy.

POPULATION

A population of 3583 adults (range, 43-86 years of age at baseline) living in Beaver Dam, Wisconsin, was studied during a 5-year period.

METHODS

Characteristics of drusen and other lesions typical of age-related maculopathy were determined by grading stereoscopic color fundus photographs using the Wisconsin Age-Related Maculopathy Grading System.

RESULTS

There was a statistically significant increased incidence of age-related maculopathy lesions with age (P < 0.05). Individuals 75 years of age or older had a significantly (P < 0.01) higher 5-year incidence of the following characteristics than people 43 to 54 years of age: larger sized drusen (125-249 microm, 17.6% vs. 2.1%; > or = 250 microm, 6.5% vs. 0.2%), soft indistinct drusen (16.3% vs. 1.8%), retinal pigment abnormalities (12.9% vs. 0.9%), exudative macular degeneration (1.8% vs. 0%), and pure geographic atrophy (1.7% vs. 0%). After adjusting for age, the incidence of early age-related maculopathy was 2.2 times (95% confidence interval 1.6, 3.2) as likely in women 75 years of age or older compared with men this age. At follow-up, late age-related macular degeneration was more likely to develop in eyes with soft indistinct drusen (6.5% vs. 0.1%) or retinal pigmentary abnormalities (7.1% vs. 0.1%) at baseline than in eyes without these lesions.

CONCLUSIONS

These population-based estimates document the high incidence of signs of age-related maculopathy in people 75 years of age or older, and in women compared with men that age. The findings demonstrate that the presence of soft drusen and pigmentary abnormalities significantly increases the risk for the development of geographic atrophy and exudative macular degeneration.

Change in visual acuity associated with cataract surgery. The Beaver Dam Eye Study

PURPOSE

Cataract is the most common age-related eye disease in most countries worldwide. However, unlike many age-related eye diseases, therapy, in the form of cataract surgery, is successful in restoring at least some function in the vast majority of patients. The purpose of this investigation is to evaluate the change in vision related to specific kinds of cataract and cataract surgery in a population-based study in Beaver Dam, Wisconsin.

METHODS

The data are derived from the Beaver Dam Eye Study, a population-based incidence study of age-related eye disease. Participants were seen for their baseline evaluation (n = 4926) between March 1, 1988, and September 14, 1990, and for a follow-up examination (n = 3684) an average of 4.8 years later. All examinations, interviews, lens photography, and grading were performed using standard protocols. The age range was 43 to 84 years at the census preceding the baseline examination.

RESULTS

For those with no cataract at baseline and without cataract surgery at follow-up, there was an average decline of 0.5 letters (on a logMAR scale) in the right eye by the follow-up examination. In persons with any cataract at baseline and without cataract surgery at follow-up, there was a decrease of four letters. When cataract surgery was done in the interval, it was associated with a significant (P < 0.0001) nine-letter (2-line) improvement in visual acuity.

CONCLUSION

Cataract surgery in this population was associated with a significant improvement in visual acuity. It is appropriate to evaluate visual acuity, cataract, and visual needs in planning for eye care in aging populations.

Health status and hypertension: a population-based study

We describe the relation between self-reported hypertension and measures of health-related quality of life (HRQOL) in a community-dwelling population. In a cross-sectional study, 1430 randomly selected adults, aged 45 to 89 years, were interviewed to obtain a medical history and health status measures, including the SF-36 questionnaire, the Quality of Well Being (QWB) index, and time trade-off (TTO) assessments. A total of 519 participants reported being affected by hypertension (HTN group). The HTN group, compared to the No HTN group, had significantly lower age-adjusted health status scores measured by the General Health scale of the SF-36 and by TTO, with differences between groups for each measure comprising approximately 5% of the total scale. HTNs also had a significant decline in general health status measures associated with increasing numbers of antihypertensive medications but not with specific classes of medications. We conclude that hypertension and hypertension drug therapy are associated with clinically meaningful decreases in reported health status.

Sex hormones and DHEA-SO4 in relation to ischemic heart disease mortality in diabetic subjects. The Wisconsin Epidemiologic Study of Diabetic Retinopathy

OBJECTIVE

Sex hormones are associated with atherogenic changes in lipoproteins and changes in glucose and insulin metabolism, yet few data are available on the relationship of sex hormones and dehydroepiandrosterone sulfate (DHEA-SO4) to ischemic heart disease (IHD) in diabetic subjects, a group with very high levels of IHD.

RESEARCH DESIGN AND METHODS

We examined the relation of total and free testosterone, sex hormone binding globulin, estrone, estradiol, and DHEA-SO4 to the 5-year IHD mortality in the older-onset diabetic subjects in the Wisconsin Epidemiologic Study of Diabetic Retinopathy (WESDR) in a matched diabetic subject-control design (two control subjects for every diabetic subject).

RESULTS

In men (n = 123), none of the sex hormones or DHEA-SO4 significantly predicted IHD mortality. In women (n = 120), lower levels of DHEA-SO4 (P < 0.01) and total testosterone (P = 0.07) predicted IHD mortality. These results were essentially unchanged after adjustment for duration of diabetes, GHb, diuretic use, and serum creatinine, which are major predictors of IHD mortality in the WESDR. Finding lower testosterone levels in diabetic subjects of IHD in women is contrary to data on risk factors, which suggests that increased androgen activity may be associated with worse IHD risk factors.

CONCLUSIONS

This study suggests that alterations in sex hormones and DHEA-SO4 are unlikely to explain a major proportion of the variation in IHD mortality in diabetic subjects.

Pattern of age-related maculopathy in the macular area. The Beaver Dam Eye Study

PURPOSE

To describe the distribution of lesions associated with age-related maculopathy by location in the macula in a population of adult Americans.

METHODS

Four thousand nine hundred twenty-six persons ranging in age from 43 to 84 years and living in Beaver Dam, Wisconsin, at the time of a census (1987-1988) were examined from 1988 to 1990. Lesions typical of age-related maculopathy were determined by masked grading of stereoscopic color fundus photographs using the Wisconsin Age-Related Maculopathy Grading System. The extent and prevalence of different types of lesions were determined for each of nine macular subfield regions: central, inner superior, inner nasal, inner inferior, inner temporal, outer superior, outer nasal, outer inferior, and outer temporal.

RESULTS

Lesions associated with early age-related maculopathy were distributed in specific patterns. Soft indistinct drusen were more prevalent in the temporal and superior quadrants than in the nasal and inferior quadrants, whereas pigmentary abnormalities associated with age-related maculopathy were more prevalent in the superior or nasal quadrants than in the inferior or temporal quadrants. After weighting for subfield area, all types of lesions were most prevalent in the central macular region.

CONCLUSION

Various lesions associated with early age-related maculopathy were located in specific patterns in the macula. It is not known whether these patterns resulted from environmental, anatomic, or physiologic factors.

Cigarette smoking and ten-year progression of diabetic retinopathy

PURPOSE

To examine the association between cigarette smoking and the incidence and progression of diabetic retinopathy.

METHODS

A population-based cohort study of 708 adult younger-onset persons with diabetes, 485 older-onset persons taking insulin, and 502 older-onset persons with diabetes not taking insulin who participated in baseline, 4-year, and 10-year examinations. Incidence and progression of retinopathy and progression to proliferative retinopathy were measured as determined by fundus photography.

RESULTS

Neither smoking status nor pack-years smoked showed significant associations with increased risk of retinopathy.

CONCLUSIONS

Cigarette smoking is not a risk factor for the long-term incidence of retinopathy. However, the failure to find an association between smoking and diabetic retinopathy does not imply that persons with diabetes who smoke should not stop as cigarette smoking is a risk factor for other complications and associated conditions of diabetes, particularly cardiovascular disease.

Tympanometric measures in older adults

Tympanometric measures were obtained in 1240 adults (2147 ears) ranging in age from 48 to 90 years. All subjects reported a negative history of otic disease, passed an otoscopic examination, and did not present a significant air-bone gap based on pure-tone audiometry. Relative to findings for younger adults, tympanometric measures for older adults in the present study showed greater variability, a slightly lower mean peak compensated static acoustic admittance (peak Ytm), and a significantly higher mean equivalent ear-canal volume (Vea). Across age in the present study, Vea tended to decrease with age and tympanogram width (TW) tended to increase with age. Relative to measures for females, males in the present study tended to have higher peak Ytm values, higher Vea values, and slightly lower TW values. Overall, our findings indicate a need to adopt criteria that account for age and gender effects in tympanometry protocols for older adults.

Interexaminer reliability of otoscopic signs and tympanometric measures for older adults

To accurately classify hearing loss and otic disorders among older adults, examiners must be able to consistently assess otoscopic signs and perform middle-ear screening tympanograms. As part of a population-based study of hearing loss in Beaver Dam, Wisconsin, the interexaminer reliability of otoscopic examinations and screening tympanograms was evaluated using 45 replicate examinations. Data from 1941 participants 48 to 91 years of age were used to compare otoscopic and tympanometric results. Overall agreement for nine otoscopic signs ranged from 73 percent (vascularity) to 100 percent (drainage). There were small examiner differences in tympanometric measures of equivalent ear-canal volume (Vea) and tympanogram width. No significant differences were observed for peak compensated static acoustic admittance and tympanogram peak pressure. Our findings suggest that examiners can be trained to consistently and accurately assess otoscopic signs and obtain reliable tympanometric results.

Association of zinc and antioxidant nutrients with age-related maculopathy

OBJECTIVE

To quantify relationships between dietary intake of zinc and antioxidant nutrients and early and late age-related maculopathy (ARM).

DESIGN

A retrospective longitudinal cohort design using data pertaining to diets in the past (1978-1980), which were assessed retrospectively using a food frequency questionnaire.

SETTING

Beaver Dam, Wis.

PATIENTS

A 50% random sample of free-living Beaver Dam Eye Study participants, 43 to 86 years of age (N = 1968).

MAIN OUTCOME MEASURE

The presence of early and late ARM determined from fundus photography.

RESULTS

People in the highest vs lowest quintiles for intake of zinc from foods had lower risk for early ARM (odds ratio = 0.6, 95% confidence interval, 0.4-1.0, P for trend < .05). This relationship appeared to be stronger for some types of early ARM (increased retinal pigment) than for others. Zinc intake was unrelated to late ARM. However, small numbers (n = 30) of people with this condition limit the ability to draw conclusions about this later stage. Levels of carotenoids were unrelated to early or late ARM. Odds for early ARM were lower in people in the highest vs lowest quintiles for the intake of vitamins C or E. However, these associations were not statistically significant.

CONCLUSIONS

The data are weakly supportive of a protective effect of zinc on the development of some forms of early ARM. Prospective studies are needed to further evaluate the potential influence of these and other nutritional factors on different types and stages of age-related macular degeneration.

Changes in visual acuity in a population. The Beaver Dam Eye Study

PURPOSE

To describe the change in visual acuity over a 5-year period in persons participating in a large population-based study.

METHODS

Best-corrected visual acuity was measured, after refraction, with logMAR charts using a modification of the Early Treatment Diabetic Retinopathy Study protocol in 3684 persons living in Beaver Dam, Wisconsin, who ranged in age from 43 to 86 years at the time of a baseline examination from 1988 to 1990, and at a follow-up examination from 1993 to 1995.

RESULTS

The change in the number of letters read correctly over the 5-year period varied from 0.4 +/- 4.9 (mean +/- standard deviation) in people between 43 and 54 years of age to -5.2 +/- 15.4 in people 75 years of age or older at baseline. Over the 5-year period, vision became impaired (20/40 or worse in the better eye) in 2.9% of the population and severely impaired (20/200 or worse in the better eye) in 0.3%. The visual angle doubled in 1.7% of the population, and 2.4% had improved vision. People 75 years of age or older at baseline were 12.5 times (95% confidence interval [Cl], 8.6-18.2; P < 0.001) more likely to have impaired vision, 9.7 times (95% Cl, 5.9-16.0; P < 0.001) more likely to have doubling of the visual angle, and 78 times more likely (95% Cl, 9.9-614.1; P < 0.001) to have severe visual impairment than people younger than 75 years of age at baseline. People 75 years of age or older who were living in nursing homes or group homes were 3.8 times more likely to have impaired vision, 3.3 times more likely to have severely impaired vision, and 5.7 times more likely to have a doubling of the visual angle than those not residing in a nursing home or a group home.

CONCLUSION

These data provide precise population-based estimates of incidence of visual loss over a wide spectrum of ages and show that decreased visual acuity in people 75 years of age is a common finding, especially in those who are in nursing homes or group homes.

Parental history of diabetes in a population-based study

OBJECTIVE

To evaluate the relative frequency of parental history of diabetes in a population-based study of younger- and older-onset groups of individuals with diabetes and a comparison group of individuals without diabetes.

RESEARCH DESIGN AND METHODS

Study participants were queried about a family history of diabetes. The frequencies of positive responses for parents and siblings were compared between younger- and older-onset groups.

RESULTS

At least one parent had diabetes in 18.6% of the families of younger-onset individuals and in 38.6% of the families of older-onset individuals. For those of younger-onset diabetes, 9.1% of fathers, 8.3% of mothers, and 1.3% of both parents had diabetes; the corresponding percentage for those of older-onset diabetes were 11.5, 23.5, and 3.6%, respectively. The difference between frequencies in mothers and fathers was significant (P < 0.0001) in the older-onset group. In the nondiabetic comparison group, for those of similar ages to the younger- and older-onset groups, the corresponding frequencies were 6.2 and 9.0% and 7.7 and 9.8% for fathers and mothers, respectively. The greater frequencies of diabetes in mothers of older-onset diabetic individuals were not accounted for by maternal age. In younger-onset individuals, the relative risk (RR) of diabetes in a sibling if the father had diabetes was 1.22 (95% CI, 0.72-2.05); if the mother had diabetes, the RR was 2.39 (95% CI, 1.64-3.48); and, if both parents had diabetes, the RR was 5.61 (95% CI, 3.37-9.34). In the older-onset individuals, the corresponding RR values were 1.69 (95% CI, 1.35-2.13) for fathers, 1.72 (95% CI, 1.44-2.06) for mothers, and 2.42 (95% CI, 1.81-3.25) for both parents.

CONCLUSIONS

These data confirm a familial influence on the frequency of diabetes. The excess of cases in mothers of older-onset diabetic individuals is compatible with both environmental and genetic influences.

Long-term incidence of lower-extremity amputations in a diabetic population

OBJECTIVE

To describe the 10-year cumulative incidence of and risk factors for lower-extremity amputations in diabetics.

DESIGN

Cohort study.

SETTING

Primary care.

PARTICIPANTS

Population-based sample (N = 879) of younger-onset diabetic persons (in whom diabetes was diagnosed before 30 years of age and who were taking insulin) and a stratified random sample (N = 956) of older-onset diabetic persons (diagnosis at or after 30 years of age) participating in baseline, 4-year, and 10-year examinations.

MAIN OUTCOME MEASURE

Amputations of the lower extremities as reported by the participants.

RESULTS

The 10-year cumulative incidence of lower-extremity amputation was 5.4% in younger-onset and 7.3% in older-onset persons. Multivariate analyses were performed by logistic regression. In younger-onset persons, age (odds ratio [OR] for 10 years, 2.0; 95% confidence interval [CI], 1.5-2.8), history of ulcers (OR,4.8; 95% CI, 2.3-9.9), diastolic blood pressure (OR, 2.1 for 10 mm Hg; 95% CI, 1.5-3.0), glycosylated hemoglobin level (OR, 1.4 for 1%; 95% CI, 1.2-1.6), sex (OR, 5.2 for men; 95% CI, 2.2-12.3), and retinopathy (OR, 1.2 for 2 steps; 95% CI, 1.1-1.4) were significantly associated with incidence of lower-extremity amputation. In older-onset persons, history of ulcers (OR, 3.3; 95% CI, 1.6-6.8), glycosylated hemoglobin level (OR, 1.3 for 1%; 95% CI, 1.1-1.5), duration of diabetes (OR, 1.6 for 10 years; 95% CI, 1.1-2.5), sex (OR, 2.6 for men; 95% CI, 1.3-4.9), diastolic blood pressure (OR, 0.7 for 10 mm Hg; 95% CI, 0.5-1.0), and proteinuria (OR, 2.4; 95% CI, 1.0-5.7) were significantly associated with incidence of lower-extremity amputation.

CONCLUSION

These data show there are several risk factors for lower-extremity amputation with potential for modification and preventive strategies.

The medical management of hyperglycemia over a 10-year period in people with diabetes

OBJECTIVE

The purpose of the study was to examine changes in the medical management of glycemia in diabetes and its relation to changes in hyperglycemia as measured by glycated hemoglobin.

RESEARCH DESIGN AND METHODS

A total of 765 patients with younger-onset diabetes diagnosed before 30 years of age and 533 older-onset diabetic patients participated in a population-based study in southern Wisconsin, at baseline (1980-1982), at 4 years (1984-1986), and at 10 years (1990-1992). Glycated hemoglobin, the presence of complications, and information regarding medical management of glycemia, hypoglycemic reactions, and socioeconomic factors were determined using standardized protocols at the three examinations.

RESULTS

In the younger-onset group, there was a significant increase (P < 0.001) in the use of three or more insulin injections per day or in the use of an insulin infusion pump from 3.6% of the cohort at baseline to 24.4% at the 10-year follow-up. This increase was associated with female sex, the presence of gross proteinuria, more education, and better glycemic control at baseline. In the older-onset group, there was a significant (P < 0.05) increase in the proportion of patients taking insulin, from 49.2% at baseline to 61.9% at the 10-year follow-up. This was associated with being younger, having a longer duration of diabetes, having higher glycated hemoglobin values, and having more education at baseline, or developing proliferative diabetic retinopathy or macular edema between baseline and the 4-year follow-up.

CONCLUSIONS

These data suggest a change in the pattern of use of insulin to treat people with diabetes. However, there is still a large number of individuals with poorly controlled diabetes in the population.

The incidence of hypertension in insulin-dependent diabetes

BACKGROUND

There are few epidemiologic data describing the long-term incidence of hypertension in people with diabetes.

METHODS

In a population-based study performed in southern Wisconsin, 765 individuals diagnosed as having diabetes when they were younger than 30 years and taking insulin participated in baseline, 4-year, and 10-year examinations. Blood pressure was measured by standardized protocols,and hypertension was defined as a mean systolic blood pressure of 160 mm Hg or more ( > or = 140 mm Hg in those younger than 25 years) and/or mean diastolic blood pressure of 95 mm Hg or more ( > or = 90 mm Hg in those younger than 25 years) and/or history of hypertension with the use of antihypertensive medication.

RESULTS

The prevalence of hypertension at baseline was 17.3%. The 10-year incidence of hypertension was 25.9%. The incidence of hypertension was greater with older age, longer duration of diabetes, higher glycosylated hemoglobin level, proteinuria, more severe retinopathy, and male gender. After other risk factors were controlled for, the 10-year incidence of hypertension was significantly related to higher glycosylated hemoglobin level (odds ratio, 1.23 per percentage increase; 95% confidence interval, 1.13 to 1.34) presence of gross proteinuria (odds ratio, 3.64; 95% confidence interval, 2.26 to 5.85), longer duration of diabetes (odds ratio, 1.03 per year of diabetes; 95% confidence interval, 1.01 to 1.04), and being male (odds ratio, 1.93; 95% confidence interval, 1.34 to 2.77).

CONCLUSION

These data suggest that control of hyperglycemia and prevention of gross proteinuria may lead to a reduction in the long-term incidence of hypertension.

Visual sensitivity and age-related eye diseases. The Beaver Dam Eye Study

OBJECTIVE

To evaluate the relationships between visual sensitivity and age-related ocular disorders.

DESIGN

Prevalence survey of age-related eye diseases.

SETTING

Beaver Dam, Wisconsin.

PARTICIPANTS

A total community sample of persons 43-84 at the time of the census (1987-1988) was invited to participate (n = 5.926).

MAIN OUTCOME MEASURE

Visual sensitivity was measured by a perimeter. Sensitivities were evaluated with regard to age, sex and age-related eye diseases.

RESULTS

Sensitivity was inversely associated with age and was lower in women in each age stratum. Central cataract, cataract surgery, and late age-related maculopathy were significantly related to decreased sensitivity in multivariate analyses.

CONCLUSIONS

Visual sensitivity, an indication of the ability of the eye to detect a light stimulus, was diminished in those with central cataract, cataract surgery, and late age-related maculopathy. This may be related to diminished vision in environmental conditions of low illumination. Since visual sensitivity is relative easy to determine, this test may have use as a surrogate to assess functional vision loss. Also, although cataract surgery often leads to improved high contrast acuity, there may be a loss in low contrast settings.

Prevalence of self-reported erectile dysfunction in people with long-term IDDM

OBJECTIVE

The purpose of this report is to examine the prevalence of erectile dysfunction and relationships to other characteristics in men with younger-onset diabetes.

RESEARCH DESIGN AND METHODS

In a population-based cohort study in southern Wisconsin, prevalence of erectile dysfunction was measured based on self reports in men who were 21 years of age or older, were < 30 years of age at diagnosis of diabetes, had 10 or more years of diabetes, and were taking insulin (n = 365).

RESULTS

Of the study group, 20% reported a history of erectile dysfunction. The prevalence of erectile dysfunction increased with increasing age (from 1.1% in those 21-30 years of age to 47.1% in those 43 years of age or older, P for trend < 0.0001) and with increasing duration of diabetes (P for trend < 0.0001). Erectile dysfunction was associated with presence of severe diabetic retinopathy, a history of peripheral neuropathy, amputation, cardiovascular disease, a higher glycosylated hemoglobin, use of antihypertensive medications, and higher BMI.

CONCLUSIONS

These data suggest that tighter glycemic control and careful selection of antihypertensive medications might prove beneficial.

Relation of glycemic control to diabetic microvascular complications in diabetes mellitus

OBJECTIVE

To describe the relation between glycated hemoglobin and the incidence or progression, or both, of diabetic microvascular complications in persons with insulin-dependent (IDDM) and non-insulin-dependent diabetes mellitus (NIDDM).

DESIGN

Population-based on cohort study.

SETTING

An 11-county area in southern Wisconsin.

PATIENTS

All persons with IDDM diagnosed before age 30 and taking insulin (n = 996) and a probability sample (based on duration of disease) of persons diagnosed with diabetes at age 30 or older who were either taking insulin (n = 674) or not taking insulin (n = 696) and who participated in a baseline examination from 1980 to 1982. Survivors of the cohort were re-examined again in 1984 to 1986 and 1990 to 1992.

MEASUREMENTS

The incidence and progression of diabetic retinopathy was determined by masked grading of stereoscopic color fundus photographs using the modified Early Treatment Diabetic Retinopathy Study severity scale. Gross proteinuria was determined using a dipstick. Ten-year incidence of renal dialysis or transplantation or loss of tactile sensation or of temperature sensitivity was based on self-reported history.

RESULTS

The glycated hemoglobin level at baseline was strongly related to the incidence or progression, or both, of diabetic retinopathy, the incidence of gross proteinuria, and the incidence of loss of tactile sensation or temperature sensitivity in persons with either IDDM or NIDDM.

CONCLUSIONS

These prospective epidemiologic data suggest that glycemic control is similarly related to the incidence and progression of diabetic microvascular complications in both IDDM and NIDDM. However, further evidence from clinical trials in persons with NIDDM is necessary to assess the risks and benefits of such treatment in preventing these complications.

Serum antioxidants and age-related macular degeneration in a population-based case-control study

OBJECTIVE

To investigate relationships between levels of tocopherols and carotenoids in the serum and age-related macular degeneration (ARMD).

DESIGN

A nested case-control study within a population-based cohort.

PARTICIPANTS

Cases included a sample of subjects with retinal pigment abnormalities with the presence of soft drusen (n = 127) or with late ARMD (geographic atrophy [n = 9]) or neovascular and exudative macular degeneration (n = 31). An equal number of controls (167 pairs) were selected from among participants in the Beaver Dam Eye Study. The controls had no photographic evidence of soft drusen, retinal pigment abnormalities, or late ARMD and were matched with cases for age, sex, and current smoking status.

DATA COLLECTION

Presence and severity of ARMD were determined from masked grading of fundus photographs obtained from 1988 to 1990. Levels of individual carotenoids and tocopherols were determined in serum collected at the same time.

RESULTS

Average levels of individual carotenoids were similar in cases and controls. Average levels of vitamin E (alpha-tocopherol) were lower in people with exudative macular degeneration (P = .03). However, the difference was no longer statistically significant after controlling for levels of cholesterol in the serum. Persons with levels of lycopene, the most abundant carotenoid in the serum, in the lowest quintile were twice as likely to have ARMD. Levels of the carotenoids that compose macular pigment (lutein with zeaxanthin) in the serum were unrelated to ARMD.

CONCLUSIONS

Very low levels of one (lycopene) but not other dietary carotenoids or tocopherols were related to ARMD. Lower levels of vitamin E in subjects with exudative macular degeneration compared with controls may be explained by lower levels of serum lipids.

Relation of sex hormones and dehydroepiandrosterone sulfate (DHEA-SO4) to cardiovascular risk factors in postmenopausal women

Sex hormones play a major role in determining the risk of cardiovascular disease. While several studies have shown that reduced sex hormone-binding globulin is associated with an atherogenic pattern of lipoproteins and increased glucose concentrations in premenopausal women, little data are available examining the association of sex hormone-binding globulin and sex hormones with cardiovascular risk factors in postmenopausal women, a group with high rates of cardiovascular disease. The investigators hypothesized that in postmenopausal women decreased sex hormone-binding globulin and increased testosterone would be associated with an atherogenic pattern of cardiovascular risk factors. The sex hormone-binding globulin, total and free testosterone, estrone, and dehydroepiandrosterone sulfate (DHEA-SO4) in 253 postmenopausal women who were not taking hormones were measured in a population-based study, the Beaver Dam Eye Study (Beaver Dam, Wisconsin, 1988-1990). Sex hormone-binding globulin was significantly inversely correlated with body mass index (r = -0.53, p 0.001), glycosylated hemoglobin (r = -0.34, p < 0.001), and diastolic blood pressure (r = -0.25, p < 0.001), and positively correlated with high density lipoprotein cholesterol (HDL cholesterol) (r = 0.31, p < 0.001), and HDL cholesterol/total cholesterol (r = 0.31, p < 0.001). Total (r = -0.20, p < 0.01) and free (r = -0.14, p < 0.05) testosterone were significantly inversely correlated with HDL cholesterol/total cholesterol ratio. Total testosterone concentrations were also significantly positively correlated with total cholesterol (r = 0.15), body mass index (r = 0.16), and systolic (r = 0.17) and diastolic (r = 0.18) blood pressures (all p < 0.01). DHEA-SO4 was not associated with any of the metabolic variables, while estrone was inversely associated only with the HDL cholesterol/total cholesterol ratio (r = 0.13, p < 0.05). The authors conclude that increased androgenization in postmenopausal women is associated with atherogenic changes in cardiovascular risk factors.