Sites of Care
Care of the older diabetic patient, similar to the care of other complex geriatric patients, has become a multidisciplinary issue with very high stakes in terms of vascular, renal, and ocular disability. Recent studies have demonstrated the value of careful management on the improvement in patient outcomes, and large-scale studies are under way to deter or prevent the emergence of clinical disease.
Treatment of Diabetes - Geriatric Medicine
Increasingly, the focus of care is planning a comprehensive, multidisciplinary treatment and assessment program designed to prevent end-organ injury and to intervene early in the course of illness. It is an encouraging time to be involved in the treatment of diabetic patients, particularly outpatients treated early in the course of their illness. Improved care of the vascular and renal complications in those with advanced disease has also produced promise for their higher quality of life.
Demographics, Epidemiology, and Risk Factors
Diabetes mellitus prevalence increases with age, and the numbers of older persons with diabetes are expected to grow as the elderly population increases in number (Figure 46.1). The National Health and Nutrition Examination Survey (NHANES III) demonstrated that, in the population over 65 years old, almost 18% to 20% have diabetes. Of great diagnostic and clinical significance is that one-half of those with diabetes mellitus are not aware they have the disease. Other abnormalities in carbohydrate metabolism that have been observed include an additional 20% to 25% older patients meeting the criteria for impaired glucose tolerance. These unknown diabetic individuals and those potentially at risk were uncovered using glucose tolerance tests, which are very sensitive to abnormalities in carbohydrate economy.
Prevalence of Gestational Diabetes Mellitus
Recent data show that gestational diabetes mellitus (GDM) prevalence has increased by ~10-100% in several race/ethnicity groups during the past 20 years. A true increase in the prevalence of GDM, aside from its adverse consequences for infants in the newborn period, might also reflect or contribute to the current patterns of increasing diabetes and obesity, especially in the offspring. Therefore, the public health aspects of increasing GDM need more attention.
The frequency of GDM usually reflects the frequency of type 2 diabetes in the underlying population. Established risk factors for GDM are advanced maternal age, obesity, and family history of diabetes.
Spontaneous hypoglycemia in adults is of two principal types: fasting and postprandial. Symptoms begin ...
Unquestionably, there are ethnic differences in the prevalence of GDM. In the U.S., Native Americans, Asians, Hispanics, and African-American women are at higher risk for GDM than non-Hispanic white women. In Australia, GDM prevalence was found to be higher in women whose country of birth was China or India than in women whose country of birth was in Europe or Northern Africa. GDM prevalence was also higher in Aboriginal women than in non-Aboriginal women. In Europe, GDM has been found to be more common among Asian women than among European women. The proportion of pregnancies complicated by GDM in Asian countries has been reported to be lower than the proportion observed in Asian women living in other continents. In India, GDM has been found to be more common in women living in urban areas than in women living in rural areas.
The trend toward older maternal age, the epidemic of obesity and diabetes, and the decrease in physical activity and the adoption of modern lifestyles in developing countries may all contribute to an increase in the prevalence of GDM. Because GDM is associated with several perinatal complications, and because women with GDM and their offspring are also at increased risk of developing diabetes later in life, it is critical to assess trends in GDM prevalence to allocate appropriate resources to perinatal management and postpartum diabetes prevention strategies. Characterizing trends in GDM might also help to understand possible mechanisms for the increase of obesity and type 2 diabetes, especially in children. Recent data show that GDM prevalence has increased by ~ 16 - 127% in several race/ethnicity groups during the past 20 years. These variations may depend on differences in methodology and study populations across studies. Methodological issues are described below as well as studies of trends in GDM. Some studies calculated the "cumulative incidence" (defined as the percentage of pregnancies in which GDM was recognized) because GDM frequency was calculated among screened pregnancies regardless of whether they delivered an infant. However, most of the studies identified only women who delivered, and therefore they calculated the "prevalence" of GDM at delivery. For simplicity, the term "prevalence" of GDM will be used for all studies, since the GDM cumulative incidence estimates are similar to the prevalence estimates, given the small number of preggnancies that were screened but did not deliver an infant.
The incidence of diabetes mellitus is approximately 2 per 1000 among those older than 45 and increases for those individuals more than 75 years old. Prevalence is much higher in older Hispanics, African Americans, Native Americans (Indians), Scandinavians, Japanese, and Micronesians.
Diabetes mellitus is the most common chronic endocrine disorder, affecting an estimated 5% to 10% of the adult population in industrialized Western countries, Asia, Africa, Central America and South America, and it has a large impact on society. The International Diabetes Federation (IDF) estimated that there were 151 million people with diabetes in 2000. Despite methodological differences, this was similar to the present estimate for a comparable population of 147 million. The IDF has subsequently released estimates of the numbers of people with diabetes for 2003 of 194 million and forecasts for 2025 of 334 million. The clinical characteristics of the diabetic population and their comorbidities have been obtained mainly from hospitals or community-based surveys. The accompanying shift in lifestyle to more sedentary activity with higher-fat diets and resultant obesity apparently underlies much of the increased prevalence of diabetes mellitus. The Saudi population is over 18 million and is rapidly growing. Previous national health surveys have provided information on the prevalence in the northwestern, southwestern, northern, eastern and central provinces.
Individuals with diabetes mellitus who are older than 65 usually have noninsulin-dependent diabetes (NIDDM). Insulin-dependent diabetes mellitus (IDDM) accounts for only 5% to 10% newly diagnosed diabetes mellitus in late life. In addition, a small proportion of older individuals who initially have NIDDM appear to become insulin dependent over time. A few clues as to who will require insulin exist. Ketosis at the time of diagnosis suggests that insulin therapy will be necessary. However, some elderly individuals with diabetes and ketosis can subsequently be treated with oral agents. The human leukocyte antigen (HLA)-DR3 serotype is more common in older adults who require insulin treatment. The frequency of antibodies to islet cells in older diabetic patients is not increased.
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