Lack of Health Insurance and Decline in Overall Health In Late Middle Age
Source: Baker DW, et al. N Engl J Med. 2001;345:1106-1112.
It is intuitive that uninsured Americans would use fewer healthcare services. Whether insurance status is related to overall health in late middle age is little studied. As many as 1 in 6 persons age 55-64 are uninsured in the United States. Baker and colleagues examined the health status of persons included in the Florida Health and Retirement Survey Database (n = 9824) as observed over a 4-year time period. Over the study period, 79.6% were continuously insured, 10.9% intermittently insured, and 9.5% continuously uninsured.
Uninsured persons were 2-2.5 times more likely to report a major decline in overall health, more heavily weighted among those continuously uninsured. New difficulties with mobility (eg, walking or stair-climbing) were also more common in uninsured individuals.
The deleterious effects of uninsured status were not related to gender, ethnicity, or income, but better baseline health was associated with greater risk for major decline in health status among the uninsured. The number of persons uninsured over age 55 is increasing. The observation that uninsured status increases the likelihood of negative health outcomes is concerning.
Long-Term Weight Loss with Sibutramine
Source: Wirth A, Krause J. JAMA. 2001;286:1331-1339.
The burgeoning epidemic of obesity and its consequences shows no signs of diminution. Currently available pharmacotherapy tools have enjoyed only modest use in the clinical setting. Long-term trials are necessary to convince the physician and patient populations that pharmacotherapy of obesity is meritorious. This 1-year trial of obese adults (BMI > 30) used sibutramine 15 mg on a daily continuous or daily intermittent schedule vs. placebo. The intermittent schedule used a 7-week hiatus of pharmacotherapy after each 3-month segment, based upon the observation that weight reductions tend to slow after this interval.
Subsequent to the 4-week run-in period, at 1 year patients on treatment lost a mean of 4% of their body weight (continuous regimen) and 3.5% on the intermittent schedule, both of which results were significantly greater than placebo. Although sibutramine has been reported to be associated with changes in blood pressure, no blood pressure changes were seen during the study period in this population. Sibutramine is effective in long-term (1 year) management of obesity.
Prediction of All-Cause and Cardiovascular Mortality in Elderly People from One Low Serum Thyrotropin Result
Source: Parle JV, et al. Lancet. 2001; 358:861-865.
Subclinical hyperthyroidism (SCH) is defined as a subnormal TSH level accompanied by normal levels of T4 and T3; as is implied in the name designation, persons must also be free of symptoms of hyperthyroidism. The pathologic consequences (or lack thereof) have been thus far ill-defined. Parle and colleagues evaluated the impact of SCH upon mortality in a large population (n = 1191) of persons older than age 60 followed for up to 10 years (mean follow-up, 8.2 years). Of the study population, 6% fulfilled diagnostic criteria for SCH.
All-cause mortality was significantly increased at years 2, 3, 4, and 5 after study entry for those with SCH, mostly due to an increased risk of death from circulatory diseases. Earlier reports have indicated an increased risk of atrial fibrillation in persons with SCH. Parle et al suggest that persistently low TSH levels in asymptomatic persons with normal levels of T4 and T3 are indicative of increased mortality risk; whether reducing T4 or T3 levels to a point where TSH is normalized will reduce risk of mortality is not yet known.
Prevalence of Hereditary Hemochromatosis in Late-Onset Type 1 Diabetes Mellitus
Source: Ellervik C, et al. Lancet. 2001;358:1405-1409.
It comes as a surprise to many clinicians that hemochromatosis (HCRM) is literally one of the most common genetic disorders in persons of northern European descent; in America, it has a gene frequency of 10%, hence it is more frequent than such disorders as cystic fibrosis. HCRM can manifest diversely, including liver disease, diabetes, heart failure, arthritis, and pituitary hypogonadism. Ellervik and colleagues postulated that HCRM is often overlooked as an etiology of, or contributor to, such disorders.
The study population included 716 type 1 adult-onset diabetics. Adult diabetics were chosen because systemic manifestations of HCRM usually manifest after age 50. The odds ratio (4.6) for homozygous HCRM in the diabetic population when compared to the unselected comparison population suggests a relevant role for HCRM in adult onset type 1 diabetes.
All patients who were HCRM homozygotes manifested an elevated serum transferrin saturation. Ellervik et al conclude that HCRM, a potentially correctable cause of diabetes and other maladies, is often overlooked. Their data suggest that, extrapolating from their Danish population, 15-20 cases of type 1 diabetes per million population could be prevented by discovery and appropriate treatment of HCRM with simple venesection. They further suggest that any type 1 adult onset diabetic merits screening for HCRM, since disease progress could be favorably affected by venesection control of HCRM.
Hormone Replacement Therapy and Dry Eye Syndrome
Source: Schaumberg DA, et al. JAMA. 2001;286:2114-2119.
Dry eye syndrome (DES), also known as keratoconjunctivitis sicca, can cause substantial debilitation due to adverse symptoms of dryness and irritation, as well as the morbidity of increased risk of corneal infection, ultimately potentially leading to permanent visual impairment. Unfortunately, management tools for DES are often unsatisfactory.
The combination of estrogen and progesterone to menopausal women, hormone replacement therapy (HRT), is used by more than one third of American women, but the relationship between HRT and DES is not yet studied. Schaumberg and colleagues used the data set of the participants in the Women’s Health Study (n = 39,876) to evaluate the relationship between HRT, estrogen replacement therapy (ERT), or non-use of hormone replacement with DES.
HRT use was significantly associated with DES. Estrogen replacement therapy (ERT) was associated with the highest prevalence of DES (9.1%), compared with HRT users (6.7%) and never-users of HRT (5.9%).
The mechanism(s) by which gonadal steroids might influence ocular lubrication is uncertain. Basic science studies have suggested that androgens favorably effect lacrimal and meibomian gland function, but estrogen may exacerbate dry eye. Schaumberg et al suggest that clinicians inform potential recipients of HRT/ERT that an increased likelihood of DES may be associated with its use.
Association Between Myeloperoxidase Levels and Risk of Coronary Artery Disease
Source: Zhang R, et al. JAMA. 2001; 286:2136-2142.
The association between inflammatory markers and the presence of atherosclerosis suggests that C-reactive protein, adhesion molecules, and other cytokines are potentially etiologically involved. Moreover, there is some substantiation for the use of such markers to predict risk of acute vascular events.
Myeloperoxidase (MPO) is an enzyme that is secreted from a variety of cells, such as neutrophils and macrophages. Normally, MPO is stored within quiescent cells, but is not released until the cells are activated, as occurs in states of acute inflammation. There is a putative link between MPO and endothelial dysfunction. Zhang and colleagues sought to establish the relationship between MPO activity and coronary artery disease. Study subjects included 333 adults, approximately half of whom had angiographically-demonstrated CAD.
MPO levels were significantly higher in persons with CAD than controls. Comparing levels of MPO, those in the highest quartile of MPO had almost a 9-fold increased odds ratio of CAD, compared with those in the lowest quartile. Zhang et al suggest that MPO levels may serve as a marker to identify persons with CAD who are not otherwise detected by typical risk factors.