Trends in the Prevalence and Ratio of Diagnosed to Undiagnosed Diabetes According to Obesity Levels in the U.S.

Abstract

FRANK VINICOR, MD, MPH 1OBJECTIVE -To examine trends in the prevalence of diagnosed and undiagnosed diabetes and the proportion of total cases previously diagnosed, according to obesity status in the U.S. over the past 40 years.RESEARCH DESIGN AND METHODS -We assembled data from five consecutive cross-sectional national surveys: National Health Examination Survey I (1960Survey I ( -1962, National Health and Nutrition Examination Survey (NHANES) I (1971-1974), NHANES II (1976-1980, NHANES III (1988), and NHANES 1999-2000. Diagnosed diabetes was ascertained, and height and weight were measured in adults aged 20 -74 years in all surveys. In NHANES II, NHANES III, and NHANES 1999 -2000, a fasting glucose level Ն126 mg/dl was used to identify cases among individuals not reporting diabetes. Design-based analyses and Bayesian models estimate the probability that prevalence of diabetes increased within four BMI groups (Ͻ25, 25-29, 30 -34, and Ն35 kg/m 2 ). 1976 -1980 and 1999 -2000, significant increases in the prevalence of diagnosed diabetes (3.3-5.8%, probability Ͼ99.9%) were accompanied by nonsignificant increases in undiagnosed diabetes (2.0 -2.4%, 66.6%). This resulted in an increase in total diabetes (5.3-8.2%, Ͼ99.9%) and a modest nonsignificant increase in the proportion of cases that were diagnosed (62-70%, 62.4%). However, these trends varied considerably by BMI level. In individuals with BMI Ն35 kg/m 2 , diagnosed diabetes increased markedly (from 4.9% in 1960, to 8.6% during 1976 -1980, to 15.1% in 1999 -2000; probability Ͼ99.9%), whereas undiagnosed diabetes declined considerably (12.5% during 1976 -1980 to 3.2% in 1999 -2000, probability of increase 4.5%) Therefore, the proportion of total diabetes cases that were diagnosed increased from 41 to 83% (probability 99.9%) among individuals with BMI Ն35 kg/m 2 . By comparison, changes in prevalence within BMI strata Ͻ35 kg/m 2 were modest and there was no increase in the percent of total cases that were diagnosed. RESULTS -In the U.S. population aged 20 -74 years betweenCONCLUSIONS -National surveys over the last several decades have found large increases in diagnosed diabetes, particularly in overweight and obese individuals, but this has been accompanied by large decreases in undiagnosed diabetes only among individuals with BMI Ն35 kg/m 2 . This suggests that improvements in diabetes awareness and detection are most prominent among this subgroup.

Prevalence of diabetes mellitus in Croatia

“…The proportion of undiagnosed persons was higher in men and lower in older and obese individuals, as reported in most studies [18,20,29,30]. As these data depend on various factors, there might even be as many as 150 undiagnosed patients with DM to every 100 diagnosed individuals with diabetes [31].…”

Hospital admissions associated with body mass index in Canadian adults

“…Obesity and overweight contribute significantly to morbidity and mortality and account for a significant percentage of overall health-care costs. 17 Excess body weight has been linked to many diseases 17 such as cardiovascular disease, 18 diabetes 19 and other metabolic disorders, 20 cancer, 21 pulmonary obstructive disease, 22 gallbladder stone, 23 arthritis. 24 Health-care expenditures associated with obesity are substantial and increasing.…”

The Chronic Kidney Disease Epidemic

“…Although some would argue that it is not the obesity per se but rather the associated diseases (hypertension and diabetes), other, more subtle influences, such as obesity-related inflammation/oxidative stress, also may contribute (31). Figure 2 shows trends for hypertension (Ͼ140/90 mmHg), high cholesterol (Ͼ240 mg/dl), smoking, diabetes (total and undiagnosed), CKD, and microalbuminuria from the National Health Examination Survey (NHES); NHANES I, II, III; and 1999 through 2000 national surveys (32)(33)(34)(35). Diabetes and obesity have increased, whereas other risks such as hyperlipidemia, smoking, and hypertension have declined.…”

“…Treatment strategies with lower BP goals and early ACE inhibition and angiotensin receptor blocker use may be working. Supporting this argument are the findings of better BP and cholesterol control in the segments of the population with obesity and diabetes (33,46). ACE inhibition/angiotensin receptor blocker use has nearly doubled in the CKD (with and without diabetes) populations from the NHANES III (1988 through 1994) to the 1999 through 2002 survey and has increased nearly as great in incident ESRD patients in the past few years (21).…”