Adverse selection, moral hazard, and wealth effects in the Medigap insurance market

Using data from a longitudinal study of the recently retired we attempt to separate the moral hazard effect of Medicare supplementary (Medigap) insurance on health care expenditures from the adverse selection effect of poor health on Medigap coverage. We find evidence of adverse selection, but its magnitude is unlikely to create serious efficiency problems. Taking adverse selection into account reduces the estimate of the moral hazard effect. In addition, we find a strong positive wealth effect on the demand for supplementary insurance.     

Evaluation of the results of external choledochoduodenostomy for retained, recurrent, or primary common duct stones.

Twenty-five patients were treated for retained, recurrent, or primary common duct stones by permanent drainage of the biliary tract with external choledochoduodenostomy. Twenty-one patients had common duct stones which became evident two to fifty years after the initial biliary tract procedure and which may represent stones formed in the common duct. Three recent patients had a clinical history of primary common duct stones, had stones which were soluble in chloroform-methanol solution, and had hepatic bile which was lithogenic as determined by evaluating the molar percentage of cholesterol, phospholipid, and bile salt in bile samples obtained at the time of choledochoduodenostomy. These data suggest that further stone formation is possible and that permanent bypass of the sphincter of Oddi is indicated to prevent recurrent bile duct obstruction. Long-term evaluation of the results of external choledochoduodenostomy indicates that the procedure is safe and effective in the prevention of recurrent biliary tract calculi.     

Adolescent depressive disorder: a population-based study of ICD-10 symptoms

OBJECTIVE: Earlier studies have suggested that symptoms of depressive disorder in adolescents may differ from those found in adults. Even so, diagnostic criteria developed in adults have come to be widely applied to younger subjects. This study examines the frequency of ICD-10 symptoms in depressive disorder and their association with severity in a large community sample of adolescents aged 15 to 18 years. METHOD: A six-wave prospective study of adolescent health and emotional wellbeing in 2032 Australian secondary school students provided an opportunity to conduct a two-phase study of adolescent onset depression. A self-administered computerised form of the revised Clinical Interview Schedule (CIS-R) was used as a first phase diagnostic measure. Second phase assessment using the Composite International Diagnostic Interview (CIDI) allowed the delineation of a group fulfilling criteria on both instruments. The ICD-10 symptoms and severity profiles for depression were generated with standard algorithms. RESULTS: 1947 (95.8%) out of 2032 subjects in the designated sample completed phase 1 assessment at least once. Participation rates at phase 2 interviews were 93%. Over the 30-month study period 69 subjects (10 male, 59 female) fulfilled criteria for ICD-10 depressive episodes on both the CIS-R and CIDI. Thirty-one per cent (n = 21) had experienced a severe episode, 46% (n = 32) moderate and 23% (n = 16) mild episodes. Loss of interest and pleasure, decreased energy and fatigue, sleep disturbance, suicidal ideation and diminished concentration most clearly distinguished adolescents with depressive disorder from controls. Self-reproach and guilt, psychomotor agitation and/or retardation and appetite disturbance with weight change showed the clearest increase in frequency with increasing severity of episode. The somatic syndrome was reported by close to one in three of those with a severe depressive episode, but was uncommon in those with mild and moderate episodes. CONCLUSIONS: The ICD-10 diagnostic criteria are applicable to depressive disorder in older adolescents. With the exception of depressed mood, found in one in five non-cases, all other symptoms were common in cases and uncommon in non-cases. Practitioner awareness of symptoms indicating the presence and severity of disorder should enhance early identification and choice of treatment in adolescent depression.     

An Investigation of the Impact of Posttraumatic Stress Disorder on Physical Health

In a large sample of Gulf War veterans (N = 2301) we examined the relations between PTSD symptoms assessed immediately upon returning from the Gulf War and self-reported health problems assessed 18–24 months later. PTSD symptomatology was predictive of self-reported health problems over time for both men and women veterans, even after the effects of combat exposure were removed from the analysis. Female veterans reported significantly more health problems than male veterans, however, there was no interactive effect of gender and PTSD on health problems. These findings provide further support for the theory that psychological response to stressors impacts health outcome.     

Endotoxemia during supraceliac aortic crossclamping is associated with suppression of the monocyte CD14 mechanism: possible role of transforming growth factor-beta1

PURPOSE: Monocyte CD14 and its soluble form (sCD14) mediate the proinflammatory response to endotoxemia. The aim of this study was to measure the changes to these factors after major aortic surgery and the possible inhibitory role of transforming growth factor-beta(1) (TGF-beta(1)) during these procedures. METHODS: Twenty-four patients with supraceliac aortic crossclamping during thoracoabdominal aortic aneurysm (TAAA) repair and 12 patients with infrarenal aortic crossclamping as part of infrarenal aneurysm repair (AAA) were studied. Blood was collected at incision, aortic clamping, and reperfusion and at 1, 8, and 24 hours after reperfusion. Samples were assayed for endotoxin, peripheral blood monocyte CD14 expression, sCD14, tumor necrosis factor-alpha, and TGF-beta(1). RESULTS: Although there was significant endotoxemia on reperfusion in both groups of patients, peak plasma endotoxin levels were significantly higher in patients with TAAA (P =.001). Monocyte CD14 and plasma sCD14 were significantly decreased in patients with TAAA at reperfusion and 1 hour after reperfusion (P <.01, both points). In patients with AAA, a significant upregulation of CD14 was observed at 24 hours after reperfusion (P <.01), but no significant changes in sCD14 were observed. TNF-alpha showed no significant changes during the study period in both groups. In patients with TAAA, TGF-beta(1) showed significant elevation at all time points (P <.01); whereas in patients with AAA, TGF-beta(1) showed no significant changes. CONCLUSION: Splanchnic ischemia reperfusion in patients who undergo supraceliac aortic clamping is associated with peripheral blood monocyte CD14 suppression and significant elevation of TGF-beta(1). TGF-beta(1) may play an important role in modulating the immune response to endotoxemia during major aortic aneurysm surgery.     

X-radiation induces 8-hydroxy-2'-deoxyguanosine formation in vivo in rat mammary gland DNA

Ionizing radiation is a carcinogen that induces oxidative DNA damage. 8- Hydroxy-2'-deoxyguanosine (8-OHdG) is a relatively abundant, mutagenic lesion that is widely regarded as a reliable index of oxidative DNA damage. The purpose of this study was to examine the effects of X- radiation on levels of 8-OHdG in the context of an experimental model for breast cancer in which chronic radiation exposure has been shown to be carcinogenic in Sprague-Dawley rats. A secondary objective of this study was to determine if the use of phenol during DNA isolation affected the concentration of 8-OHdG subsequently measured. Our results indicate that a profoundly carcinogenic dose of radiation induced a small but significant increase in 8-OHdG concentration in mammary gland DNA, and that the use of a phenol-based versus a salt-based method of DNA isolation had no significant impact on the levels of 8-OHdG detected in either control or irradiated tissue.