Occupational characteristics and cognitive performance among elderly male twins

OBJECTIVE

To examine the effect of occupational characteristics on cognitive status change in members of the NAS-NRC Twins Registry of World War II veterans.

METHODS

Participants completed the modified Telephone Interview for Cognitive Status (TICS-m) on three occasions spanning a period of approximately 7 years. Based on factor analysis, occupational characteristics were interpreted as reflecting general intellectual demands (GI), human interaction and communication (HC), physical exertion (PE), and visual attention (VA).

RESULTS

Based on regression analysis of TICS-m change that was dependent on twin pairing and additionally covarying for education, age at each testing event, medical conditions, and initial TICS-m score, higher GI was associated with a modest longitudinal improvement in TICS-m performance, whereas higher PE and VA were both associated with a modest decline. Subsequent analysis revealed that these significant effects were present among dizygotic twins, but not among monozygotic twins.

CONCLUSIONS

Previous findings of a relationship between occupational characteristics and cognitive performance in later life may be partially explained by genetic factors; however, until these genes are identified, occupational characteristics may be useful markers.

Age effects of coronary artery bypass graft on cognitive status change among elderly male twins

Background: Research regarding long-term cognitive outcome following coronary artery bypass graft (CABG) is inconsistent, which may be due in part to differential genetic and environmental influences within most study samples.

Methods: The authors examined the effect of CABG on cognitive status change scores in members of the National Academy of Sciences–National Research Council Twins Registry of World War II veterans. Subjects were administered the modified Telephone Interview for Cognitive Status (TICS-m) at approximately 3-year intervals between 1990 and 2002 as part of an epidemiologic study of dementia.

Results: Based on co-twin control analyses using a repeated-measures analysis of variance matching twins discordant for CABG within the pair (n = 464 individuals) across three age categories (63 to 70, 71 to 73, 74 to 83), the authors found at follow-up that men who had CABG between ages 63 and 70 showed an increase in TICS-m scores and performed better than their co-twin who did not have the procedure. No significant differences were found within twin pairs for the older two age groups following CABG surgery. This age effect was replicated when comparing individuals positive for CABG surgery with nonfamilial, age- and education-matched controls who were negative for CABG.

Conclusions: In this study of twin pairs who share many genetic and environmental risks for cerebrovascular problems, the results suggest that timing of the CABG procedure may be important to predicting positive cognitive outcomes.

A longitudinal study of gender differences in depressive symptoms from age 50 to 80

The Obvious Depression Scale was administered to 739 community residents at ages 50, 60, and 80 years, with 151 present at all waves. Although selective attrition influenced the level of depressive symptoms in cross-sectional vs. longitudinal samples, both sets of analyses revealed higher scores in women than in men at ages 50 and 60, but not at age 80. Men showed increases in depressive symptoms from age 60 to 80, but women did not (interaction p < .002). This interaction was not present in somatic symptoms, which increased across time in both genders. Potential explanations include differential changes in social roles with aging.

Modulated kinase activities in cells undergoing tumour necrosis factor-induced apoptotic cell death

Tumour necrosis factor-alpha (TNF) has a variety of cellular effects including apoptotic and necrotic cytotoxicity. TNF activates a range of kinases, but their role in cytotoxic mechanisms is unclear. HeLa cells expressing elevated type II 75 kDa TNF receptor (TNFR2) protein, analysed by flow cytometry and Western analysis, showed altered c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (p38MAPK; but not MAPK) protein content and activation. There was greater JNK activation, but reduced p38MAPK activation in dying cells compared to those still to enter TNF-induced apoptosis. Moreover, cells displaying more rapid apoptosis possess higher levels of type I 55 kDa TNFR1 receptor isoform, but less TNFR2. These findings reveal differential kinase activation in TNF-induced apoptotic death.

A longitudinal study of gender differences in depressive symptoms from age 50 to 80

The Obvious Depression Scale was administered to 739 community residents at ages 50, 60, and 80 years, with 151 present at all waves. Although selective attrition influenced the level of depressive symptoms in cross-sectional vs. longitudinal samples, both sets of analyses revealed higher scores in women than in men at ages 50 and 60, but not at age 80. Men showed increases in depressive symptoms from age 60 to 80, but women did not (interaction p < .002). This interaction was not present in somatic symptoms, which increased across time in both genders. Potential explanations include differential changes in social roles with aging.

Personality factors differentially predict exercise behavior in men and women

Personality assessed with the Minnesota Multiphasic Personality Inventory (MMPI) in college was used to predict exercise behavior measured at midlife in 3,630 men and 796 women enrolled in the University of North Carolina Alumni Heart Study. Logistic regression models were fitted for each of the MMPI clinical scales to test the predictive effect of personality, gender, and their interaction on adult exercise behavior. Lower depression, social introversion, and psychopathic deviance scores were associated with increased probability of exercising in midlife for both men and women. Furthermore, better psychological health (indexed by lower hypochondriases and psychasthenia) in college was generally predictive of increased exercise for men, whereas higher scores on these same factors predicted midlife exercise for women. There were two other patterns of gender interactions: (a) for men, lower scores on hysteria and schizophrenia scales were associated with increased probability of exercising at midlife, whereas these factors were unrelated to exercise for women and (b) for women, lower ego strength and higher college scores on paranoia and mania were associated with exercise behavior at midlife. These data suggest that early adulthood personality predictors of exercise behavior at midlife are both gender-neutral and gender-specific; that is, where no gender differences exist, healthier personality traits predict exercise at midlife, and when gender differences do occur, healthier college patterns of personality predict exercise behavior for men and sedentary behavior for women.

Central nervous system serotonin function and cardiovascular responses to stress

OBJECTIVE

The objective of this study was to evaluate the impact of indices of central nervous system (CNS) serotonin function on cardiovascular reactivity to mental stress.

METHODS

Lumbar puncture was performed on 54 healthy volunteers to obtain cerebrospinal fluid (CSF) for determination of 5-hydroxyindoleacetic acid (5HIAA) levels. Genotypes were determined with respect to a functional polymorphism of the serotonin transporter gene promoter region (5HTTLPR). Subjects then underwent mental stress testing.

RESULTS

Persons with one or two long (l) 5HTTLPR alleles had CSF levels of the major serotonin metabolite, 5HIAA, that were 50% higher than those of persons with the s/s 5HTTLPR genotype. Persons with one or two l alleles or higher CSF 5HIAA levels also exhibited greater blood pressure and heart rate responses to a mental stress protocol.

CONCLUSIONS

These findings suggest the 5HTTLPR polymorphism affects CNS serotonin function, and they are consistent with the general hypothesis that CNS serotonin function is involved in the regulation of potentially health-damaging biobehavioral characteristics. In particular, the l allele could contribute, through its association with increased cardiovascular reactivity to stress, to increased risk of cardiovascular disease.

Depressive symptoms and survival of patients with coronary artery disease

OBJECTIVE

Multiple studies have shown that high levels of depressive symptoms increase the mortality risk of patients with established coronary disease. This investigation divided depressive symptoms into groups to assess their relative effectiveness in predicting survival.

METHODS

Questionnaires about the presence of depressive symptoms were administered to 1250 patients with significant coronary disease while they were hospitalized for diagnostic coronary angiography. Follow-up for mortality due to cardiac disease was conducted annually for up to 19.4 years. Factor analysis was used to divide items on the Zung Self-Rating Depression Scale into four groups: Well-Being, Negative Affect, Somatic, and Appetite. In addition, responses to a single item regarding feelings of hopelessness were available for 920 patients.

RESULTS

Well-Being and Somatic symptoms significantly predicted survival (p < or = .01). Negative Affect items were also related to survival (p = .0001) and interacted with age. A 2-SD difference in the Negative Affect term was associated with a relative risk of 1.29 for patients >50 years old and 1.70 for younger ones. Only Negative Affect remained significant in a model with the other symptom groups. Hopelessness also predicted survival with a relative risk of 1.5. Both the Hopelessness and Negative Affect items remained as independent predictors in the same model. All models controlled for severity of disease and treatment. With one exception (income and Hopelessness), results were essentially unchanged by additional controls for age, gender, and income.

CONCLUSIONS

Depressive symptoms differentially predicted survival, with depressive affect and hopelessness being particularly important. These effects were independent of disease severity and somatic symptoms and may be especially important in younger patients.

Documented head injury in early adulthood and risk of Alzheimer's disease and other dementias

BACKGROUND

The association between antecedent head injury and AD is inconsistent.

OBJECTIVE

To examine the association between early adult head injury, as documented by military hospital records, and dementia in late life; and to evaluate the interaction between head injury and APOE epsilon4 as risk factors for dementia.

METHODS

The study had a population-based prospective historical cohort design. It included men who were World War II Navy and Marine veterans, and were hospitalized during their military service with a diagnosis of either a nonpenetrating head injury or another unrelated condition. In 1996 to 1997, military medical records were abstracted to document the occurrence and details of closed head injury. The entire sample was then evaluated for dementia and AD using a multistage procedure. There were 548 veterans with head injury and 1228 without head injury who completed all assigned stages of the study. The authors estimated risk of dementia, specifically AD, using proportional hazards models.

RESULTS

Both moderate head injury (hazard ratio [HR] = 2.32; CI = 1.04 to 5.17) and severe head injury (HR = 4.51; CI = 1.77 to 11.47) were associated with increased risk of AD. Results were similar for dementia in general. The results for mild head injury were inconclusive. When the authors stratified by the number of APOE epsilon4 alleles, they observed a nonsignificant trend toward a stronger association between AD and head injury in men with more epsilon4 alleles.

CONCLUSIONS

Moderate and severe head injuries in young men may be associated with increased risk of AD and other dementias in late life. However, the authors cannot exclude the possibility that other unmeasured factors may be influencing this association.

Are SSRIs better than TCAs? Comparison of SSRIs and TCAs: a meta-analysis

In this analysis we examined studies of tricyclic antidepressants (TCAs) and selective serotonin reuptake inhibitors (SSRIs) to compare efficacy and drop-out rates. Frequency of reported side effects was also studied. Using Medline, we located 36 clinical trials of TCAs and SSRIs in a double-blind comparison. We performed a meta-analysis on these studies and on a subgroup of 21 studies that had more uniformly defined outcome criteria. The main outcome measures were efficacy for treatment completers and for the intention-to-treat group; drop-out rates due to adverse reactions and lack of efficacy; and reported side effects. Overall, the response rate to treatment for patients who completed a trial was 63.2% for SSRIs and 68.2% for TCAs (P = 0.038). For the intention-to-treat groups, these rates dropped to 48.0 and 48.6% (P, NS), respectively. Significantly more TCA-treated than SSRI-treated subjects dropped out due to either lack of efficacy or adverse reactions (30.0 vs. 24.7%, P = 0.01). Patients taking SSRIs experienced significantly more gastrointestinal problems and sexual dysfunction, whereas treatment with TCAs produced significantly more complaints of sedation, dizziness, and anticholinergic symptoms.

Hostility predicts magnitude and duration of blood pressure response to anger

The hypothesis that hostile and nonhostile individuals would differ in both magnitude and duration of cardiovascular reactivity to relived anger was tested. Participants were 66 older adults (mean age, 62; 38 women and 28 men; 70% Caucasian American, 30% African American). Each took part in a structured interview scored using the Interpersonal Hostility Assessment Technique. Later each relived a self-chosen anger memory while heart rate and systolic and diastolic blood pressures were measured continuously using an Ohmeda Finapres monitor. Hostile participants had larger and longer-lasting blood pressure responses to anger. African Americans also showed longer-lasting blood pressure reactivity to anger. Health and measurement implications are discussed.

Ambulatory cardiovascular activity in Vietnam combat veterans with and without posttraumatic stress disorder

The present study investigated the relationship between daily diary affect ratings and ambulatory cardiovascular activity in 117 male Vietnam combat veterans (61 with posttraumatic stress disorder [PTSD] and 56 without PTSD). Participants completed 12-14 hr of ambulatory monitoring and daily diary affect ratings. Compared with veterans without PTSD, veterans with PTSD reported higher negative affect and lower positive affect in daily diary ratings. No differences were detected for mean laboratory initial recordings or mean ambulatory heart rate (HR), systolic blood pressure (SBP), or diastolic blood pressure (DBP). However, compared with veterans without PTSD, veterans with PTSD demonstrated higher SBP and DBP variability and a higher proportion of HR activity (compared with initial recording values) during daily activity. There was a significant Time of Day x Group interaction for mean HR, with a trend for PTSD participants to maintain HR levels during evening hours.

Ambulatory cardiovascular activity in Vietnam combat veterans with and without posttraumatic stress disorder

The present study investigated the relationship between daily diary affect ratings and ambulatory cardiovascular activity in 117 male Vietnam combat veterans (61 with posttraumatic stress disorder [PTSD] and 56 without PTSD). Participants completed 12-14 hr of ambulatory monitoring and daily diary affect ratings. Compared with veterans without PTSD, veterans with PTSD reported higher negative affect and lower positive affect in daily diary ratings. No differences were detected for mean laboratory initial recordings or mean ambulatory heart rate (HR), systolic blood pressure (SBP), or diastolic blood pressure (DBP). However, compared with veterans without PTSD, veterans with PTSD demonstrated higher SBP and DBP variability and a higher proportion of HR activity (compared with initial recording values) during daily activity. There was a significant Time of Day x Group interaction for mean HR, with a trend for PTSD participants to maintain HR levels during evening hours.

APOE and AD concordance in twin pairs as predictors of AD in first-degree relatives

OBJECTIVE

To examine the independent effects of the APOE genotype (APOE) and concordance for AD in twin pairs on the occurrence of AD in first-degree relatives.

BACKGROUND

Studies of twins have been undertaken to investigate the influence of genes in a variety of conditions, including AD. A previous study, performed before reports linking APOE to AD, demonstrated an increase in AD among first-degree relatives of twins concordant for AD compared with relatives of discordant twins.

METHODS

In a sample of 94 twin pairs the authors examined the association between concordance for AD within the twin pair and family history of AD among first-degree relatives of twins. They then examined the extent to which the presence of the APOE epsilon4 allele in the twin pair explains the association between concordance for AD within the twin pair and family history of AD.

RESULTS

Concordance among twins was associated with increased risk of AD among relatives (logrank test, chi2 = 12.558; p = 0.0004), and the presence of at least one APOE epsilon4 allele in each member of the twin pair is also associated with increased risk of AD among family members (logrank test, chi2 = 7.712; p = 0.0055).

CONCLUSIONS

APOE genotype explains much but not all of the association between concordance among twins and increased familial risk of AD.

Cerebrovascular disease and depression symptoms in the cardiovascular health study

BACKGROUND AND PURPOSE

Evidence is mounting linking cerebrovascular disease with depressive symptoms in the elderly. Lesions in both white and gray matter have been associated with depressive symptoms and major depression. We sought to investigate the relationship between depressive symptoms and white and gray matter lesions in subjects participating in the Cardiovascular Health Study.

METHODS

In a sample of 3660 men and women who underwent a standardized interview, physical examination, and MRI scan, we examined the association between number of white and gray matter lesions and white matter grade (a measure of severity) and reported depressive symptoms using a modified version of the Centers for Epidemiologic Studies Depression (CES-D) scale. We controlled for a variety of demographic and medical variables as well as functional status and Modified Mini-Mental State Examination score.

RESULTS

The number of small (<3 mm) basal ganglia lesions was significantly associated with reported depressive symptoms, but white matter grade was not. In subsequent logistic regression models, number of basal ganglia lesions remained a significant predictor after controlling for non-MRI variables and severity of white matter lesions.

CONCLUSIONS

Our findings extend previous reports that linked cerebrovascular changes to depressive symptoms in clinical populations to a large community-based population. This report provides further evidence of the importance of basal ganglia lesions in geriatric depression.

Measures of hostility as predictors of facial affect during social interaction: evidence for construct validity

We assessed the construct validity of several self-report measures and an interview-based measure of hostility (Interpersonal Hostility Assessment Technique [IHAT]) by evaluating their associations with a behavioral indicator of hostile emotions (facial expressions during social interaction). Participants in the study were 123 volunteers (44% males and 56% females) who were recruited from local community organizations. Self-report measures (Cook-Medley Hostility Scale, Rotter Interpersonal Trust Scale, Buss-Durkee Hostility Inventory, and Spielberger Anger Expression Scale) were represented by factor scores reflecting Overt Hostility, Covert Hostility, and Hostile Beliefs. A canonical correlation analysis identified significant associations between a set of facial affect scores reflecting animosity and various measures of hostility. Specifically, increases in anger and disgust expressions and decreases in happy facial expressions were associated with high IHAT scores and high scores on self-report measures of Hostile Beliefs and Covert Hostility. Women were more expressive than men, especially concerning positive affect, and women had lower scores on self-report measures of Hostile Beliefs and Overt Hostility. IHAT scores were uncorrelated with any of the self-report factors which suggests the two assessment techniques are tapping different aspects of the hostility construct.

Symptoms of depression and changes in body weight from adolescence to mid-life

OBJECTIVE

To investigate the relationship of symptoms of depression to weight changes in healthy individuals of normal weight across a follow-up of over 20 y.

PARTICIPANTS AND DESIGN

College students (3885 men and 841 women) were administered a self-report depression measure in the mid-1960s. Their baseline body mass index (BMI) was calculated from their college medical records. Participants were contacted by mail in the late 1980s and asked to report their current height and weight as well as their smoking and exercise habits. Another measure of depressive symptoms was obtained from 3560 individuals at follow-up. Multiple regression models were used to relate changes in weight to depression scores while controlling for background (gender, baseline BMI and the gender by BMI interaction) and behavioral (exercise and smoking) predictors.

RESULTS

The relationship between depressive symptoms and body weight change took the form of an interaction with baseline BMI (P < 0.001). Those with high baseline depression scores gained less weight than their nondepressed counterparts if they were initially lean, but more if they were initially heavy. This trend was especially strong in those with high depression scores at both baseline and follow-up.

CONCLUSIONS

The findings support the hypothesis that depression exaggerates pre-existing weight change tendencies. This pattern would not have been detected by an examination of main effects alone, illustrating the need to move toward more complicated interactive models in the study of psychological factors and weight.

Psychosocial correlates of job strain in a sample of working women

BACKGROUND

This study identifies potential mediators of job strain effects on health by determining whether psychosocial factors known to predict an increased risk of cardiovascular disease and all-cause mortality are higher among women who report high levels of job strain.

METHODS

Measures of job strain and other psychosocial risk factors were obtained in a sample of 152 female employees of a local corporation. Canonical correlation and analyses of covariance were used to assess relationships between job demands and decision latitude and other psychosocial risk factors.

RESULTS

A significant (P = .002) solution to the canonical correlation analysis showed that high job demands and low decision latitude were correlated with a pattern of psychosocial factors consisting of (1) increased levels of negative emotions like anxiety, anger, depression, and hostility; (2) reduced levels of social support; and (3) a preponderance of negative compared with positive feelings in dealings with coworkers and supervisors. This pattern was confirmed by analyses of covariance that adjusted for demographic and specific job characteristics.

CONCLUSIONS

The canonical correlation analysis results provide empirical support for the job strain construct. The most important finding is that health-damaging psychosocial factors like job strain, depression, hostility, anxiety, and social isolation tend to cluster in certain individuals.

A twin study of late-onset depression and apolipoprotein E epsilon 4 as risk factors for Alzheimer's disease

A prior history of depression and the epsilon 4 allele of apolipoprotein E (APOE) have each been associated with development of Alzheimer's disease (AD). In a sample of 142 elderly twins from a large study of dementia, we examined the relation of major depression, APOE genotype and AD using time-dependent proportional hazards models. Compared against the risk for AD with no history of depression and no epsilon 4 allele, the risk ratio for AD with two epsilon 4 alleles was 2.87 (C.I. = 1.56-5.28), with one epsilon 4 allele, 1.82 (C.I. = 1.09-3.04) and with late-onset depression and no epsilon 4 allele, 2.95 (C.I. = 1.55-5.62). There was no suggestion of an interaction between prior depression and APOE genotype in their effects on AD risk. Results were similar when the sample was stratified by twin pair, so that a single genetic marker is unlikely to explain the relation among depression, APOE, and dementia. Risk ratios declined substantially with increasing intervals between the onset of depression and AD. Thus, for many individuals, the association of depression and AD may reflect the occurrence of prodromal depressive symptoms rather than a true risk relationship.

Apolipoprotein E epsilon 4 allele and hippocampal volume in twins with normal cognition

We examined the relation of APOE-epsilon 4, hippocampal volume, and cognitive performance in ten pairs of cognitively normal twins who had a mean age of 62.5 years (SD = 7.8). There were no significant differences in neuropsychological measures of the groups categorized by the presence of an epsilon 4 allele. However, the mean normalized right and left hippocampal volumes were smaller in the epsilon 4 groups compared to the group without epsilon 4. Combined with prior reports, these findings suggest that epsilon 4 is associated with differences in brain morphology that may be evident when no symptoms of dementia are present.

Depression and long-term mortality risk in patients with coronary artery disease

Previous research has established that patients with coronary artery disease (CAD) have an increased risk of death if they are depressed at the time of hospitalization. Follow-up periods have been short in these studies; therefore, the present investigation examined this phenomenon over an extended period of time. Patients with established CAD (n = 1,250) were assessed for depression with the Zung Self-Rating Depression Scale (SDS) and followed for subsequent mortality. Follow-up ranged up to 19.4 years. SDS scores were associated with increased risk of subsequent cardiac death (p = 0.002) and total mortality (p < 0.001) after controlling for initial disease severity and treatment. Patients with moderate to severe depression had a 69% greater odds of cardiac death and a 78% greater odds of mortality from all causes than nondepressed patients. Increased risk was not confined to the initial months after hospitalization. Patients with high SDS scores at baseline still had a higher risk of cardiac death > 5 years later (p < 0.005). Compared with the nondepressed, patients with moderate to severe depression had an 84% greater risk 5 to 10 years later and a 72% greater risk after > 10 years. Patients with mild depression had intermediate levels of risk in all models. The heightened long-term risk of depressed patients suggests that depression may be persistent or frequently recurrent in CAD patients and is associated with CAD progression, triggering of acute events, or both.

Interpersonal and self-reported hostility among combat veterans with and without posttraumatic stress disorder

The present study investigated self-reported and interpersonal hostility in 70 Vietnam combat veterans with and without posttraumatic stress disorder (PTSD) and 60 comparison community volunteer subjects. Veterans were 50 help-seeking, male Vietnam combat veterans with PTSD and 20 non-help-seeking male combat veterans without PTSD. Vietnam veterans with PTSD not only reported more hostility than non-PTSD veterans and healthy community volunteers, but also reacted behaviorally with more hostility during an interpersonal interaction. Compared to veterans without PTSD, veterans with PTSD reported significantly higher levels of hostility and demonstrated significantly greater non-verbal expressions of hostility during an interpersonal task. These results suggest that the level of hostility in PTSD combat veterans may be high as compared to comparison groups. The implications of these results and possible research directions are presented.

Alzheimer's disease in the National Academy of Sciences-National Research Council Registry of Aging Twin Veterans. III. Detection of cases, longitudinal results, and observations on twin concordance

OBJECTIVES

To detect cases of Alzheimer's disease (AD) in a large population of twins living throughout the United States and to examine concordance for AD in twins as a function of age and genotype for apolipoprotein E (APOE).

SETTING

Nationwide survey.

DESIGN

Multistage screening and field evaluation beginning with two telephone interviews and culminating with laboratory tests, longitudinal neuropsychological measures, physician examination, and diagnostic consensus among experts.

PARTICIPANTS

Membership in 1990-1991 of intact pairs in the National Academy of Sciences--National Research Council Registry of veteran twins, then aged 62 to 73 years.

MAIN OUTCOME MEASURES

Completeness of case detection was examined in collateral studies. Zygosity and APOE genotypes were determined by restriction mapping. Concordance was calculated by the proband method.

RESULTS

Ninety subjects who screened positively for AD were studied in person, and 60 whose differential diagnoses included AD were followed up, as were their co-twins. Sensitivity of screening was estimated at greater than 99%, but 24% of subjects refused participation after initial screening. Seven of 38 diagnoses of AD have been confirmed at autopsy, and 31 other subjects eventually met criteria for probable or possible AD (prevalence estimate, 0.42%, 95% confidence interval, 0.29% to 0.56%), with good interrater reliability (intraclass r = .86). Excluding one discordant pair with unknown zygosity, concordance rates were 21.1% (4/19) for monozygotic and 11.1% (2/18) for dizygotic probands. Concordance was 50% for twins sharing the epsilon 4/epsilon 4 genotype at APOE, but there were no affected co-twins of 15 probands with onset before age 70 years, no epsilon 4 allele, and no family history of AD. The mean (SD) period of discordance in the latter pairs was 11.3 (3.3) years.

CONCLUSIONS

The multistage case-detection approach achieved reliable and valid diagnoses of AD with high apparent sensitivity but substantial attrition after initial screening. Genetic influences in AD at this age are limited, except among homozygotes for allele epsilon 4 at APOE. Subjects with early-onset AD who lack the epsilon 4 allele are not rare, and their condition appears to have little genetic influence. They should be ideal for studies on environmental cause of AD.

Delayed onset of Alzheimer's disease with nonsteroidal anti-inflammatory and histamine H2 blocking drugs

Factors that modify onset of Alzheimer's disease (AD) may be revealed by comparing environmental exposures in affected and unaffected members of discordant twin pairs or sibships. Among siblings at high risk of AD, sustained use of nonsteroidal anti-inflammatory drugs (NSAIDs) was associated with delayed onset and reduced risk of AD. After adjustment for use of NSAIDs, there was minimal effect on onset with reported history of any of three common illnesses (arthritis, diabetes, or acid-peptic disease). However, independent of exposure to NSAIDs, onset was unexpectedly delayed in those reporting extended use of histamine H2 blocking drugs. Randomized clinical trials will be needed to affirm the utility of these drugs for prevention, but the present findings may have implications for pathogenesis: because NSAIDs block the calcium-dependent postsynaptic cascade that induces excitotoxic cell death in NMDA-reactive neurons, and because histamine potentiates such events, excitotoxicity may deserve additional investigation in AD.

Are vaginal and rectal pressures equivalent approximations of one another for the purpose of performing subtracted cystometry?

OBJECTIVE

To determine if rectal and vaginal pressures are clinically equivalent to one another for the purpose of calculating subtracted detrusor pressure during routine filling cystometry and pressure-flow voiding studies.

METHODS

A total of 140 consecutive filling and voiding cystometrograms were performed at separate sessions on 127 female patients undergoing routine clinical cystometry for a variety of clinical indications, usually urinary incontinence. In all cases, intravaginal as well as intrarectal pressures were measured simultaneously using microtip transducer pressure catheters, and two subtracted detrusor pressures were calculated throughout each study. Rectal and vaginal pressure measurements from the same patient were compared with the patient in the supine position with an empty bladder, in the erect position with a full bladder, and in the sitting position during voiding at the point of maximum urinary flow.

RESULTS

The mean pressures were similar in all cases. Although there was no statistical difference in the mean differences between the rectal and vaginal pressures in the supine-empty position (P = .5528), significant differences were noted between them in the erect-full and sitting-voiding positions (P = .0016 and P = .0033, respectively). Linear regression analysis of the data obtained in each position was carried out, plotting vaginal pressure on the x axis and rectal pressure on the y axis. The corresponding r values for each position were 0.431 for the supine-empty position, 0.547 for the erect-full position, and 0.478 for the sitting-voiding position, indicating poor correlation between pressures in individual patients. In nine patients (6.5%) with significant vaginal relaxation and large cystoceles, a steady rise in vaginal pressure was noted during bladder filling. In six patients (4.4%), one or more spontaneous vaginal contractions were noted during the course of the study, whereas in 68 (48.9%), spontaneous rectal contractions were present. Of the 68 cases where spontaneous rectal contractions were noted, these contractions faded away in 53 cases (77.9%) as the study progressed.

CONCLUSIONS

Rectal pressure and vaginal pressure are not the same during filling and voiding cystometry. Although they are reasonable approximations of each other for most qualitative clinical diagnostic purposes, potentially significant differences in subtracted detrusor pressure may occur, depending on which pressure is used as the approximation of intra-abdominal pressure. This may affect clinical management decisions in individual patients. The technique used for approximating abdominal pressure must be stated clearly in any report or publication dealing with subtracted cystometry.

Normal values for single exhalation diffusing capacity and pulmonary capillary blood flow in sitting, supine positions, and during mild exercise

Previous approaches to the measurements of pulmonary diffusing capacity (DL) and pulmonary capillary blood flow (QC) utilized either the rebreathing or the single inhalation technique in conjunction with radioisotope gas and mass spectrometry. In the present study, we utilized a newly developed rapid infrared analyzer in conjunction with the slow single exhalation technique on 100 healthy volunteers to establish normal values for DL and QC under sitting, supine, and exercise conditions. The exercise level was determined by a target heart rate: HRex = ([HRmax - HRrest]/3) + HRrest. Prediction equations based on regressions on age, sex, height, or weight were then computed for sitting, supine, and exercise values. We found that mean DL and QC increased by approximately 12 percent and 8 percent, respectively, from sitting to supine posture, and by approximately 30 percent and 100 percent, respectively, from sitting (rest) to mild exercise. These results provided a database for further studies in the single exhalation method in various clinical settings.

Inverse association of anti-inflammatory treatments and Alzheimer's disease: initial results of a co-twin control study

We conducted a co-twin control study among 50 elderly twin pairs with onsets of Alzheimer's disease (AD) separated by 3 or more years. Twenty-three male pairs (46%) were screened from the (U.S.) National Academy of Sciences-National Research Council Registry (NAS-NRC Registry) of World War II veteran twins; others (mostly women) had responded to advertisements or were referred from AD clinics. Twenty-six pairs (52%) were monozygous. The onset of AD was inversely associated with prior use of corticosteroids or ACTH (odds ratio [OR], 0.25; 95% confidence interval [CI], 0.06 to 0.95; p = 0.04). Similar but weaker trends were present among pairs discordant for history of arthritis or for prior daily use of nonsteroidal anti-inflammatory drugs (NSAIDs) or aspirin. The association was strongest when we combined use of steroids/ACTH or NSAIDs post hoc into a single variable of anti-inflammatory drugs (AIs) (OR, 0.24; CI, 0.07 to 0.74; p = 0.01). The inverse relation was strong in female (volunteer) twin pairs but was not present in the younger men from the NAS-NRC Registry. AIs had typically been taken for arthritis or related conditions, but a similar result was apparent after controlling statistically for the arthritis variable (OR, 0.08; CI, 0.01 to 0.69; p = 0.02). AIs have been proposed as a means of retarding the progression of AD symptoms, and these data suggest that AIs may also prevent or delay the initial onset of AD symptoms. Because of limitations in the case-control method, our results require corroboration with hypothesis-driven research designed to control bias and confounding.

Dose response relationship between plasma ACTH and cortisol after the infusion of ACTH1-24

The authors examined the dose response relationship between plasma ACTH and cortisol concentrations after the administration of various doses of ACTH1-24 (0.025 micrograms, 0.125 micrograms, 0.25 micrograms, 1 microgram, 250 micrograms) in dexamethasone-suppressed normal volunteers. A logarithmic dose-response relationship between the dose of ACTH administered and plasma cortisol concentration was found. Although there was considerable variability in plasma ACTH concentrations, there was, however, a definite correlation between area under the curve for ACTH and area under the curve for cortisol after the various doses of ACTH.

Acute childbirth morbidity: its measurement using hospital charges

OBJECTIVES

An analytic descriptive analysis of acute childbirth morbidity was carried out at Duke University Medical Center, comparing patients delivered by primary cesarean section with those delivered vaginally.

STUDY DESIGN

All primary cesarean deliveries and vaginal deliveries from July 1, 1981, through June 30, 1986, were combined with maternal and infant charge data. A total of 7256 patients were analyzed. A description of the charges for the associated diagnoses was carried out. A morbidity index was used to identify differences in predicted median hospital charges with 95% confidence intervals.

RESULTS

The ratio of mean primary cesarean delivery to mean vaginal delivery total charges was 2.5:1. The magnitude of the mean hospital charges was inversely related to the frequency of the indication with the lowest charges associated with dystocia and the highest with multiple pregnancy. Antepartum risk factors (increased maternal age, patient referral) were associated with increases in maternal and infant morbidity as measured by the morbidity index. Chronic maternal hypertension resulted in decreased maternal morbidity but increased infant morbidity when primary cesarean delivery was used. Although preterm delivery was associated with large increases in charges, it was not significantly altered by using primary cesarean delivery. Risk factors associated with the management of abnormalities of labor were associated with decreases in maternal and infant morbidity when primary cesarean delivery was used.

CONCLUSION

Analysis of acute childbirth morbidity, as measured by hospital charges, showed marked variation of diagnosis and risk-specific charges for patients delivered by primary cesarean section.

Dysphagia following brain-stem stroke. Clinical correlates and outcome

We studied 23 individuals (16 men, seven women; mean age 57 years) who had brainstem strokes confirmed by computed tomography of the head or magnetic resonance imaging. Videofluoroscopic modified barium-swallowing examination showed aspiration in 15 of 23 patients. Of the 15 aspirating patients, the majority had bilateral strokes with multiple lesion loci, most often in association with large-vessel disease. All 15 patients had involvement of the pons or medulla. Statistical analyses revealed a significant association between aspiration and pharyngeal residue observed under videofluoroscopy, cranial nerve IX abnormality, vocal fold weakness, and severe dysarthria. Despite initial severity, recovery was good. Following an aggressive program of aspiration prevention, over 80% of patients resumed full oral nutrition at the last follow-up.

Performance of new criteria for right ventricular hypertrophy and myocardial infarction in patients with pulmonary hypertension due to cor pulmonale and mitral stenosis

Historically, electrocardiographic criteria for right ventricular (RV) hypertrophy has achieved high specificity but low sensitivity. Recently, however, Butler-Leggett et al. have introduced three criteria that attained a 66% sensitivity in a population with RV hypertrophy due to mitral stenosis while maintaining a 95% specificity in an extensive normal control group. Electrocardiographic diagnosis of RV hypertrophy is principally dependent on changes in the QRS complex that may be masked or mimicked by myocardial infarction (MI). This dilemma has been confirmed by documentation of the low specificity of both the Selvester QRS scoring system for MI size estimation (greater than 3 points) and its screening subset (greater than 0 points) in a pure mitral stenosis population. This study introduces the population characterized by RV hypertrophy due to cor pulmonale, which has a mean pulmonary arterial systolic pressure that is higher than the mean for the mitral stenosis population and consequently suggests more severe RV hypertrophy. When compared, the Butler-Leggett criteria for RV hypertrophy are more sensitive in the new population than in the mitral stenosis population (89% versus 60%) and the Selvester QRS scoring system is less specific (12% versus 60%). Three sequential steps are suggested for electrocardiographic analysis: (1) diagnosis of RV hypertrophy using the Butler-Leggett criteria, (2) diagnosis of MI using the Selvester screening criteria in those patients with step 1 negative, and (3) estimation of MI size using the complete Selvester scoring system in patients with step 1 negative and step 2 positive.

Predictors of response to monoamine oxidase inhibitors: do they exist?

Multiple regression analysis was conducted on potential response predictors in a double-blind study of monoamine oxidase inhibitors (MAOI) and placebo treatment in 130 depressed outpatients. Positive main effects were found for sex (female), lack of prior hospitalization, presence of precipitating events. A negative main effect was found for concurrent physical illness. Treatment x predictor effects were found for distinct quality and non-reactivity. Non-reactivity was associated with positive outcome in the active drug group, but with negative outcome in the placebo group [corrected]. Distinct quality demonstrated a more complex effect, its presence being associated with decreased improvement in the treatment group and greater improvement in the control group. No atypical depressive symptoms predicted MAOI response, and we were unable to characterize a specifically responsive MAOI syndrome.

Clinical characteristics useful in screening for renovascular disease

In an effort to detect renovascular hypertension, clinical characteristics are used to select patients likely to have renal artery stenosis. We prospectively evaluated the ability of commonly used clinical features to predict the presence of renal artery stenosis in 100 hypertensive adults. All subjects had conventional renal arteriography. Renal artery stenosis was diagnosed if there was 50% or more stenosis of a main renal artery. Eighteen of the 100 had renal artery stenosis. The presence of a bruit was strongly associated with renal artery stenosis (P less than .0005). In patients without a bruit, only refractory hypertension was associated with the presence of renal artery stenosis (P = .051). These data suggest that a bruit and refractory hypertension are associated with renal artery stenosis, but that other clinical features investigated may not be and that other means of screening for renovascular disease are needed.

Extravascular extravasation of radiographic contrast media. Effects of conventional and low-osmolar agents in the rat thigh

We compared the damage resulting from intradermal injection of four commonly used radiographic contrast media in laboratory rats. Sixty percent meglumine diatrizoate (Reno M 60) and ioxaglate (Hexabrix) produced significantly more ulceration and crusting on gross inspection and more necrosis, edema, and hemorrhage on histologic evaluation than iopamidol 300 (Isovue) or 0.9% (normal) saline. Thirty percent meglumine diatrizoate (Reno M Dip) had an intermediate toxicity, resulting in significantly more visible swelling and more microscopically detected hemorrhage than iopamidol or saline, but less ulceration/crusting and necrosis than Reno M 60 and ioxaglate. Since the three contrast agents of similar osmolality produced different degrees of tissue damage, our results suggest that factors other than high osmolality are partially responsible for determining the severity of injuries from extravasated contrast media.

The effect of a telephone family assessment intervention on the functional health of patients with elevated family stress

A randomized trial of a telephone family assessment intervention was conducted during a 2.5 month period on 224 ambulatory primary care patients, aged 18-49 years, who were selected according to self-report of elevated family stress levels. Family physicians conducted telephone interviews to collect information from patients on their supportive and stressful family members. The working hypothesis was that this process would lead to reduction in the patient's family stress and to improvement in family support and personal health status. Patients reported that the intervention caused them to think about their family support and helped them to feel better. Comparison of family factor and functional health scores before and after intervention also indicated a limited beneficial effect, but only for a small subset of black patients. These results suggest that the telephone family assessment alone is inadequate as an intervention and should be strengthened to include professional assistance to patients for the family problems that are identified by the assessment.

Changing rates of cesarean delivery: the Duke experience, 1978-1986

There was a steady increase in the yearly cesarean delivery rate, from 14.0 to 24.8%, between July 1, 1978 and June 30, 1986 at Duke University Medical Center; this was associated predominantly with an increase in the rate of primary cesarean deliveries. The three most frequent major diagnoses associated with primary cesarean delivery changed significantly over the study period. Fetal compromise became the most commonly associated diagnosis (from third), dystocia second (from first), and maternal disease third (from second). The categories of fetal positional abnormalities (fourth), abnormalities of placentation (fifth), and multiple pregnancy (sixth) did not change in rank. Primary cesarean delivery patients were compared with patients who delivered vaginally using odds ratios, prevalence, and population-attributable fractions. The risk factors of nulliparity, gestational age less than 37 weeks, late decelerations, and referral had the largest impact on the primary cesarean rate. Decreases in rates related to an increased tolerance of abnormalities of labor were overshadowed by the effects of increased concerns related to fetal health.

Early-onset Alzheimer's disease: clinical predictors of institutionalization and death

Follow-up observations were made of 92 white patients with early-onset Alzheimer's disease to determine the demographic, clinical, and neuropsychological factors predictive of institutionalization or death. The cumulative mortality rate 5 years after entry into the study was 23.9%, compared with an expected rate of 9.5%. The 5-year cumulative rate of admission to nursing homes was 62.8%. The language ability of the patients on entry to the study, their scores on a brief screening test of cognitive function, and their overall ratings of clinical dementia were found to be predictors of subsequent institutional care and death. The age of the patients had a significant modifying effect on these predictive factors, resulting in a greater risk of institutionalization and death in younger patients with severe cognitive impairment as compared with older individuals with the same degree of dysfunction.

Alzheimer's disease: a study of epidemiological aspects

A case-control study was performed to determine the possible roles of various environmental factors, prior illnesses, drug use, and personal habits in the development of Alzheimer's disease. Such information was collected from 40 patients with onset of dementia prior to age 70 and from 80 community control subjects matched for age, sex, and race. No significant differences were found between patients and control subjects in toxic environmental exposures, animal contacts, smoking, drinking, or unusual dietary habits. A significantly higher frequency of prior thyroid disease was found in women patients than in women control subjects (25.0% and 7.1%, respectively). A history of severe head injury was also obtained significantly more often among the patients than among the controls (15.0% and 3.8%, respectively). Aside from these differences, which may prove to be important associative factors in this illness, there appeared to be no major premorbid demographic or clinical factors associated with this form of dementia. There was evidence, however, of a genetic factor that was manifested in an excess of dementia and mental retardation (including Down's syndrome) in families of patients with Alzheimer's disease.

Normal sister chromatid exchange levels in hospital sterilization employees exposed to ethylene oxide

This study was undertaken to determine whether a specific group of hospital workers exposed to ethylene oxide (ETO) in sterilizing areas showed evidence of increased levels of sister chromatid exchange (SCE) formation. SCE frequencies were determined for 14 sterilizer workers and 14 matched controls. Time-weighted average (TWA) and peak ambient levels of ETO were measured in the sterilizing areas. Results indicated that all sterilizer workers were exposed to less than 5 parts per million TWA of ETO and that there were no statistically significant differences in SCE levels between sterilizer workers and controls. Smoking habits did appear to be associated with increased SCE levels. In this particular hospital setting no evidence of genetic effects stemming from employees' exposure to low levels of ETO was found.

Alzheimer's disease: genetic aspects and associated clinical disorders

Genetic aspects and associated clinical disorders were studied in a consecutive series of 68 men and women in whom Alzheimer's disease appeared at or before age 70. Secondary cases of dementia were found in 17 (25%) of the families, affecting 22 of the probands' siblings and parents. The cumulative incidence of Alzheimer's disease in these relatives was approximately 14% at age 75. An increased frequency of Down's syndrome was observed among relatives of the probands: a rate of 3.6 per 1,000, as compared with an expected rate of 1.3 per 1,000. A history of thyroid disease was established in 9 (19.6%) of the 46 female probands, a frequency greater than that reported in the general population. There was no excess of hematological malignancies among the blood relatives, and parental age at the time of birth of the probands did not differ from the norm. The results of this study indicate that early-onset Alzheimer's disease is associated with a genetic factor manifested in a substantial familial aggregation of dementia, a probable excess of Down's syndrome in the probands' relatives, and a possible association with thyroid dysfunction in women with this form of dementia.

Logistic model estimation of death attributable to risk factors for cardiovascular disease in Evans County, Georgia

Linear logistic analysis of the relationship of cardiovascular disease risk factors to an overall measure of health effect, ten-year mortality, revealed significant associations of death with systolic blood pressure, age, sex, diabetes mellitus, smoking, cholesterol, obesity (Quetelet index), race and social index. Attributable risk and population attributable risk estimates were derived from the model by changing actual variable values to target values. The results confirmed systolic hypertension and smoking as major public health problems and diabetes mellitus as a powerful risk factor for death. The small detrimental effect of cholesterol on probability of death limits the potential for an overall beneficial effect of preventive intervention. In fact, drug intervention in two reported trials of cholesterol reduction had negative overall effects. Demonstration of the association of a characteristic with a specific disease state does not alone justify attempts to eliminate the high risk state from a population. An overall detrimental health effect must be documented by suitable studies before trials of preventive intervention are undertaken or recommendations made to the public.

Risk of stroke in asymptomatic persons with cervical arterial bruits: a population study in Evans County, Georgia

A survey of the rural community in Evans County, Georgia, revealed cervical arterial bruits in 72 (4.4 per cent) of 1620 persons 45 years of age of older without previous stroke, transient ischemic attacks, or overt ischemic heart disease. The prevalence of such asymptomatic bruits increased with age and was greater in women and persons with hypertension. We estimated the risk of stroke associated with cervical bruits during a six-year follow-up period, taking age and blood pressure into account. The presence of asymptomatic bruits was associated with a significantly higher risk of stroke in men but not in women, with odds ratios of 7.5 and 1.6, respectively. Despite the high risk of stroke among men with bruits, the correlation between the location of the bruits and the type of subsequent stroke was poor. Moreover, cervical bruits in men were a risk factor for death from ischemic heart disease. We suggest that asymptomatic cervical bruits are an indication of systemic vascular disease and do not themselves justify invasive diagnostic procedures or surgical correction of underlying extracranial arterial lesions.

Cytomegalovirus infection and chronic hemodialysis

Serologic and virologic studies of cytomegalovirus (CMV), a virus infection often disseminated in immunosuppressed patients, were initiated among hemodialysis patients, home dialysis partners, hemodialysis center personnel, and several groups of patients. No evidence was found of activation or persistence of CMV infections in connection with chronic renal disease or in association with hemodialysis. Evidence of increased CMV activation and/or infection was found among individuals who had re-entered the dialysis program following renal allograft rejection. The data indicate that dialysis personnel and home dialysis partners are not at increased risk for CMV infection. The findings of this study, which contrast with those pertaining to hepatitis B infection, suggest that different mechanisms are responsible for establishing both infection and persistence of CMV and hepatitis B.