Psychosocial issues in long-term space flight: overview

Anecdotal evidence of the individual and interpersonal problems that occurred during the Shuttle-Mir Space Program (SMSP) and other long-duration Russian/Soviet missions, and studies of personnel in other isolated and confined extreme (ICE) environments suggest that psychosocial elements of behavior and performance are likely to have a significant impact on the outcome of long-duration missions in space. This impact may range from individual decrements in performance, health and well being, to catastrophic mission failure. This paper reviews our current understanding of the psychosocial issues related to long duration space missions according to three different domains of behavior: the individual domain, the interpersonal domain and the organizational domain. Individual issues include: personality characteristics that predict successful performance, stress due to isolation and confinement and its effect on emotions and cognitive performance, adaptive and maladaptive coping styles and strategies, and requirements for the psychological support of astronauts and their families during the mission. Interpersonal issues include: impact of crew diversity and leadership styles on small group dynamics, adaptive and maladaptive features of ground-crew interactions, and processes of crew cohesion, tension and conflict. Organizational issues include: the influence of organizational culture and mission duration on individual and group performance, and managerial requirements for long duration missions. Improved screening and selection of astronaut candidates, leadership, coping and interpersonal skills training of personnel, and organizational change are key elements in the prevention of performance decrements on long-duration missions.

Circannual pattern of hypothalamic-pituitary-thyroid (HPT) function and mood during extended antarctic residence

The seasonal variation in thyroid function and mood was examined in 10 men and two women who spent the 1997 or 1998 austral winter at McMurdo Station, Antarctica. Serum samples of TSH, free T3 and free T4 were collected each month over a 10-month period (October-August), along with responses to the Profile of Mood States (POMS) and the Center for Epidemiologic Studies - Depression (CES-D) Scale. Both TSH and mood (a summary score created from the POMS depression, anger, fatigue and confusion subscales) exhibited a circannual pattern with peaks during the months of November and July and a trough during the months of March and April. High levels of tension-anxiety and confusion were preceded by declines in free T3 and T4. However, increases in tension-anxiety and total mood disturbance also preceded a decline in free T3 levels, suggesting a feedback of mood on T3 levels. Levels of free T4 were independently associated with preceding increases in anger scores. These results support the hypothesis that the symptoms characteristic of the winter-over syndrome is a state of relative CNS hypothyroidism. This model of seasonal variation in thyroid function and mood also has implications for an understanding of potential mechanisms underlying the association between latitude and SAD or S-SAD.

Impairment in cognitive and exercise performance during prolonged antarctic residence: effect of thyroxine supplementation in the polar triiodothyronine syndrome

Humans who work in Antarctica display deficits in cognition, disturbances in mood, increased energy requirements, a decline of thyroid hormone products, and an increase of serum TSH. We compared measurements in 12 subjects, before deployment (baseline), with 11 monthly studies during Antarctic residence (AR). After 4 months of AR (period 1), half of the subjects (T(4) group) received L-thyroxine [64 nmol.day(-)(1) (0.05 mg.day(-)(1))]; and the other half, a placebo (placebo group) for the next 7 months of AR (period 2). During period 1, there was a 12.3 +/- 5.1% (P < 0.03) decline on the matching-to-sample (M-t-S) cognitive task and an increase in depressive symptoms, compared with baseline. During the intervention in period 2, M-t-S scores for the T(4)-treated group returned to baseline values; whereas the placebo group, in contrast, showed a reduced M-t-S score (11.2 +/- 1.3%; P < 0.0003) and serum free T(4) (5.9 +/- 2.4%; P < 0.02), compared with baseline. The change in M-t-S score was correlated with the change in free T(4) (P < 0.0003) during both periods, and increases in serum TSH preceded worsening scores in depression, tension, anger, lack of vigor, and total mood disturbance (P < 0.001) during period 2. Additionally, the submaximal work rate for a fixed O(2) use decreased 22.5 +/- 4.9% in period 1 and remained below baseline in period 2 (25.2 +/- 2.3%; P < 0.005) for both groups. After 4 months of AR, the L-thyroxine supplement was associated with improved cognition, which seems related to circulating T(4). Submaximal exercise performance decrements, observed during AR, were not changed with this L-thyroxine dose.

The use of complementary and alternative medicine by primary care patients. A SURF*NET study

BACKGROUND

Despite the increased use and acceptance of complementary and alternative medicine (CAM) practices and practitioners by patients and health care providers, there is relatively little information available concerning the reasons for use or its effect on patient health status and well-being.

METHODS

We conducted a survey of 542 patients attending 16 family practice clinics that belong to a community-based research network in San Diego, California, to determine patients' reasons for using CAM therapies in conjunction with a visit to a family physician and the impact of these therapies on their health and well-being.

RESULTS

Approximately 21% of the patients reported using one or more forms of CAM therapy in conjunction with the most important health problem underlying their visit to the physician. The most common forms of therapy were visiting chiropractors (34.5%) of CAM users), herbal remedies and supplements (26.7%), and massage therapy (17.2%). Recommendations from friends or coworkers, a desire to avoid the side effects of conventional treatments, or failure of conventional treatments to cure a problem were the most frequently cited reasons for using these therapies. Use of practitioner-based therapies was significantly and independently associated with poor perceived health status, poor emotional functioning, and a musculoskeletal disorder, usually low back pain. Use of self-care-based therapies was associated with high education and poor perceived general health compared with a year ago. Use of traditional folk remedies was associated with Hispanic ethnicity.

CONCLUSIONS

Sociodemographic characteristics and clinical conditions that predict use of CAM therapies by primary care patients in conjunction with a current health problem vary with the type of therapy used.

Relationship of climate, ethnicity and socioeconomic status to Kawasaki disease in San Diego County, 1994 through 1998

BACKGROUND

Kawasaki disease (KD) is the most common cause of acquired heart disease in children in the United States. By monitoring trends in patient numbers and demographics during a 5-year period, we were able to explore the relationship between climate, ethnicity, socioeconomic status and susceptibility to KD.

METHODS

We conducted active surveillance for all patients hospitalized with KD in San Diego County from 1994 through 1998. Data on seasonal variation in monthly rainfall and temperature were obtained from the US Meteorological Service. Patient sex, age, date of admission and self-reported ethnicity were identified from patient medical records. Socioeconomic status was assessed on the basis of insurance status among patients hospitalized at a single institution.

RESULTS

During the 5-year period there were 169 cases of KD in San Diego County. The overall annual incidence of KD in children < 5 years of age ranged from 8.0 to 15.4/100 000. KD incidence was inversely associated with average monthly temperature (r = -0.47, P < 0.001) and positively associated with average monthly precipitation (r = -0.52, P < 0.001). Asian/Pacific Islanders < 5 years of age were 2.7 times as likely and Hispanics were one-third as likely to be hospitalized for KD than children from all other ethnic groups combined. Children with private or military insurance in all ethnic groups were more likely to have a diagnosis of KD than children with government assistance or no insurance. After controlling for insurance status, only Asian/Pacific Islanders remained at increased risk (rate ratio, 2.14) for KD relative to all other ethnic groups combined.

CONCLUSION

KD is a common childhood vasculitis of unknown etiology. The skewed ethnic distribution and seasonality are consistent with the hypothesis that KD is an infectious disease that is influenced by environmental and genetic factors.

Sociocultural change and health status among the Seri Indians of Sonora, Mexico

The influence of changes in sociocultural status on obesity, arterial blood pressure, and depression was examined in a cohort of 81 Seri Indians living in two communities in Sonora, Mexico. Residents of the less acculturated and modernized community, Desemboque, exhibited significantly higher waist circumference and prevalence of obesity than did residents of the more acculturated and modernized community of Punta Chueca. The prevalence of obesity was also significantly associated with low levels of acculturation and modernization, while the prevalence of clinically significant depressive symptoms was associated with low levels of modernization and household income. Lifestyle incongruity was a significant independent risk factor for body mass index and depressive symptom scores but not for arterial blood pressure. The results support the notion of a curvilinear relationship between health status and sociocultural change in which health status initially declines with increasing lifestyle incongruity but eventually improves with increasing acculturation, modernization, and income.

Summary of research issues in behavior and performance in isolated and confined extreme (ICE) environments

The papers in this section of the workshop describe behavioral and performance charges in isolated and confined extreme (ICE) environments. These changes include increased disturbances of mood, rates of psychiatric disorder, and interpersonal tension, and a disruption of circadian rhythms. The workshop ended with four specific recommendations for future research.

Behavior and performance on long-duration spaceflights: evidence from analogue environments

BACKGROUND

Analyses of data collected in Antarctica since 1963 were conducted to identify features of behavior and performance likely to occur during long-duration missions in space.

METHODS

The influence of mission duration and station latitude on POMS mood scores was examined in 450 American men and women who wintered-over in Antarctica between 1991 and 1998. The influence of crewmember social characteristics, personality traits, interpersonal needs, and station environments on measures of behavior and performance at the end of the austral winter was examined in 657 American men who wintered-over between 1963 and 1974. Both data sets were used to examine the influence of crew social structure on individual performance.

RESULTS

Seasonal variations in mood appear to be associated with the altered diurnal cycle and psychological segmentation of the mission. Concurrent measures of personality, interpersonal needs, and coping styles are better predictors of depressed mood and peer-supervisor performance evaluations than baseline measures because of the unique features of the station social and physical environments and the absence of resources typically used to cope with stress elsewhere. Individuals in crews with a clique structure report significantly more depression, anxiety, anger, fatigue and confusion than individuals in crews with a core-periphery structure. Depressed mood is inversely associated with severity of station physical environment, supporting the existence of a positive or "salutogenic" effect for individuals seeking challenging experiences in extreme environments.

CONCLUSION

Behavior and performance on long-duration spaceflights is likely to be seasonal or cyclical, situational, social, and salutogenic.

Predictors of behavior and performance in extreme environments: the Antarctic space analogue program

BACKGROUND

To determine which, if any, characteristics should be incorporated into a select-in approach to screening personnel for long-duration spaceflight, we examined the influence of crewmember social/ demographic characteristics, personality traits, interpersonal needs, and characteristics of station physical environments on performance measures in 657 American men who spent an austral winter in Antarctica between 1963 and 1974.

METHODS

During screening, subjects completed a Personal History Questionnaire which obtained information on social and demographic characteristics, the Deep Freeze Opinion Survey which assessed 5 different personality traits, and the Fundamental Interpersonal Relations Orientation-Behavior (FIRO-B) Scale which measured 6 dimensions of interpersonal needs. Station environment included measures of crew size and severity of physical environment. Performance was assessed on the basis of combined peer-supervisor evaluations of overall performance, peer nominations of fellow crew-members who made ideal winter-over candidates, and self-reported depressive symptoms.

RESULTS

Social/demographic characteristics, personality traits, interpersonal needs, and characteristics of station environments collectively accounted for 9-17% of the variance in performance measures. The following characteristics were significant independent predictors of more than one performance measure: military service, low levels of neuroticism, extraversion and conscientiousness, and a low desire for affection from others.

CONCLUSIONS

These results represent an important first step in the development of select-in criteria for personnel on long-duration missions in space and other extreme environments. These criteria must take into consideration the characteristics of the environment and the limitations they place on meeting needs for interpersonal relations and task performance, as well as the characteristics of the individuals and groups who live and work in these environments.

Sleep and mood during a winter in Antarctica

Seasonal variations in sleep characteristics and their association with changes in mood were examined in 91 American men and women who spent the 1991 austral winter at three different research stations in Antarctica. Measures of total hours of sleep over a 24-hr period, duration of longest (i.e., "nighttime") sleep event, number of sleep events, time of sleep onset, and quality of sleep remained unchanged over the course of the austral winter (March through October). However, exposure to total darkness based on station latitude was significantly associated with total hours of sleep, duration of longest sleep event, time of sleep onset, and quality of sleep. Reported vigor the previous month was a significant independent predictor of changes in all five sleep measures; previous month's measures of all six POMS subscales were significant independent predictors of sleep quality. Sleep characteristics were significant independent predictors of vigor and confusion the following month; total sleep, longest sleep event, sleep onset and sleep quality were significant independent predictors of tension-anxiety and depression. Changes in mood during the austral winter are preceded by changes in sleep characteristics, but prolonged exposure to the photo-periodicity characteristic of the high latitudes appears to be associated with improved sleep. In turn, mood changes appear to affect certain sleep characteristics, especially sleep quality.

Stages of change in mood and behavior during a winter in Antarctica

Seasonal variation in mood and behavior was examined in 87 American men and women who spent the 1991 austral winter at three different research stations in Antarctica. The South Pole station (90 degrees S) crew reported a significant decline in tension/anxiety, depression, anger, confusion, and fatigue from March to August, followed by a significant increase in tension/anxiety and fatigue and a significant decline in vigor from August to October. The McMurdo station (78 degrees 51' S) crew also reported a significant decline in tension/anxiety from March to July and a significant increase in tension/anxiety from July to August. In contrast, the Palmer station (64 degrees 46' S) crew experienced no significant changes in any mood subscale from May to October. The nonlinear pattern of change in mood suggests that adaptation to prolonged isolation and confinement in an extreme environment occurs in two or three stages.

Longitudinal studies of behavior and performance during a winter at the South Pole

BACKGROUND

Evidence of a specific pattern of performance decrement in isolated and confined (ICE) environments has not been consistently demonstrated in previous research.

HYPOTHESIS

Decrements in performance in ICE environments: a) occur in a linear, dose-response manner; b) occur in stages; or c) do not occur at all.

METHODS

There were 83 members of the United States Antarctic Program who spent an austral winter at the Amundsen-Scott South Pole Station (90 degrees S) between 1991 and 1994 and completed the Profile of Moods States (POMS) once a month for an 8-mo period from March through October.

RESULTS

Over the entire 8-mo period, there was a decline in depression (p = 0.007) and vigor (p < 0.0001), and an increase in fatigue (p = 0.059) and tension-anxiety (p = 0.075). Of these four measures, only vigor exhibits a linear pattern. Mean scores for tension-anxiety and fatigue were lower during the first half of the winter than the second half (p = 0.074 and 0.077, respectively). In comparisons between each quarter and the remaining three quarters, averaged mean tension-anxiety scores and fatigue scores were lower during the second quarter (p = 0.009 and 0.03, respectively), and higher during the fourth quarter (p = 0.025 and 0.035, respectively) than during the previous three quarters combined.

CONCLUSIONS

The duration of optimal performance in isolated and extreme environments and the explanation for changes in performance during long duration assignments in such environments both depend on what behavioral measure is used to assess performance.

People in high latitudes: the "Big Five" personality characteristics of the circumpolar sojourner

The personality of the polar sojourner has been of interest to psychologists for a number of years. Using the NEO Five Factor Inventory, this study examined the general personality factors of the polar worker compared to a normative population, and how these factors differ according to the worker's occupational classification and the polar region in which he or she is working. It was found that polar workers scored higher than a normative group on all factors except Neuroticism. Comparisons across occupational groups showed that scientists were lower than military personnel on Extraversion and lower than technical/support staff on Agreeableness and Conscientiousness. The analysis by polar region indicated that Antarctic workers were higher than Arctic personnel on Extraversion, Agreeableness, and Conscientiousness. A group of Italian Antarctic personnel, completing a translated form of the NEO-FFI, scored lower than the rest of the polar groups on all factors. These findings are discussed in light of various features of the polar environment and Gunderson's 3-predictor model of polar adaptability.

Physicians who are certified in family practice and psychiatry: who are they and how do they use their combined skills?

BACKGROUND

The American Board of Family Practice (ABFP) and the American Board of Psychiatry and Neurology (ABPN) have jointly established their guidelines for a combined residency training program in family practice-psychiatry. As the new combined programs develop, it is of interest to learn about those physicians who are already board certified in both family practice and psychiatry.

METHODS

The ABFP provided a list of the 39 physicians in the United States who in 1995 held certification by both the ABFP and the ABPN. A questionnaire eliciting demographic data, information on practice patterns, and comments was mailed to each of them.

RESULTS

Ninety percent of the physicians responded. Sixty percent reported that they practice both family medicine and psychiatry, 20 percent practice in communities with a population of 30,000 or less, and the great majority were very satisfied with their choice of specialties.

CONCLUSION

The responding family physician-psychiatrists chose their specialties one at a time, in sequence. Although their practice patterns are interesting, we believe residents who select a combined residency will have different practice patterns, choosing to practice both specialties from the outset. After graduates of these newly emerging combined residencies have entered practice, it will be useful to study how they make use of their combined skills.

The influence of women on the health care-seeking behavior of men

BACKGROUND

Gender and social relationships are believed to have a strong influence on health care attitudes and behavior. This study was designed to determine the effect of the gender of closely associated persons on the health care-seeking behavior of persons of the opposite sex.

METHODS

We developed a 14-item questionnaire that requested information on social and demographic characteristics, health status, and influences on the decision to seek health care, and administered it to 314 consecutive patients seen at two family medicine clinics in San Diego, California. Data were analyzed by means of one way analysis of variance for continuous variables and the chi-square test for categorical variables. Additionally, data were analyzed by means of a multivariant logistic regression model that calculated odds ratios and 95% confidence intervals.

RESULTS

Men were 2.7 times more likely than women to be influenced to seek health care by a member of the opposite sex (95% CI, 1.6 to 4.6). Married patients were 2.4 times more likely than unmarried patients to be influenced to seek health care by a member of the opposite sex (95% CI, 1.4 to 4.3).

CONCLUSIONS

Women exert an important influence on the decisions of men to seek health care.

Social skills training for drug prevention in high-risk female adolescents

BACKGROUND

The effectiveness of social skills training/social network restructuring in the primary and secondary prevention of drug use was examined in a multiethnic cohort of 296 female adolescents ages 14 to 19 years who were pregnant or parenting and/or at risk for drug use.

METHODS

Subjects were randomly assigned to one of two conditions: (a) PALS Skills Training or (b) a control intervention involving no skills training. PALS Skills Training is a combination of cognitive and behavioral techniques to improve social skills and to restructure the teens' social network. All students also participated in a 16-week normative education "Facts of Life" course.

RESULTS

The prevalence of alcohol and any drug use increased significantly over the three assessment periods in the PALS Skills group but not in the No Skills group. Teens in the PALS Skills group who reported no drug use at baseline were 2.9 times as likely to be using marijuana than teens in the No Skills group at 3 months postintervention. PALS Skills Training was no more effective in the secondary prevention of drug use than the control intervention.

CONCLUSIONS

Social skills training was found to be ineffective as a means of primary prevention among non-drug-using high-risk adolescents and may even be counterproductive as a means of primary prevention of marijuana use in this population. When combined with normative information on drug use prevalence, acceptability, and hazards, social skills training is no more effective as a means of secondary prevention than normative education alone.

Subsyndromal seasonal affective disorder in Antarctica

The seasonality of depressed mood was examined in 70 men and women who spent the 1991 austral winter at three American research stations in Antarctica. Seasonal Pattern Assessment Questionnaire global seasonality scores increased significantly from late summer (February/March) to midwinter (July/August; p < .001). Only one case of seasonal affective disorder (SAD) was found during midwinter, but the prevalence of subsyndromal SAD increased significantly, from 10.5 to 28.4 per 100, during this period. Station latitude was significantly associated with SAD-specific symptoms and global Structured Interview Guide for the Hamilton Depression Rating Scale-Seasonal Affective Disorders Version scores in midwinter and in early spring (October). The results suggest that even clinically normal individuals are likely to experience symptoms of subsyndromal SAD in high latitude environments, that these variations become more pronounced with increasing latitude, and that they can be detected through repeated administrations of instruments such as the Seasonal Pattern Assessment Questionnaire and Structured Interview Guide for the Hamilton Depression Rating Scale-Seasonal Affective Disorders Version.

Depressive symptoms in overweight and obese older adults: a test of the "jolly fat" hypothesis

The association between body weight and depressive symptoms in older adults was examined in a population-based study of 2,245 noninstitutionalized men and women aged 50 to 89 years living in Rancho Bernardo, California, U.S.A. The prevalence of Beck Depression Inventory scores > or = 13 was inversely associated with body weight in men, but not in women. Overweight and obese 50- to 69-yr-old women were more depressed than women with a body mass index below 25 kg/m2, but the difference was only marginally significant (p = 0.09). When age, health status and medication use were controlled, the odds of being depressed were 0.34 (p = 0.004) in overweight men and 0.28 (p = 0.09) in obese men, compared to men with a body mass index below 25 kg/m2. In this cohort, depression in men was inversely associated with body weight, supporting the "Jolly Fat" hypothesis. The likelihood that more stigma is attached to excessive weight in women than men may account for the lack of an inverse association between weight and depression in women.

Psychological functioning among members of a small polar expedition

BACKGROUND

While depressed mood, insomnia, irritability and impaired cognition represent common responses to the physical and psychosocial stressors associated with polar environments, wide variations exist in their expression and the degree to which they adversely affect the health and performance of polar expeditioners. In particular, the process of successful adaptation to polar environments and the psychosocial characteristics associated with this process remains poorly understood.

HYPOTHESIS

Psychosocial characteristics associated with successful coping with typical stressors are also associated with successful adaptation in polar environments.

METHODS

The 4 men and 3 women participating in a 3-week scientific expedition in the Canadian High Arctic completed a battery of psychological questionnaires, including the Profile of Mood States (POMS), prior to their departure to Isachsen, N.W.T. In Isachsen, subjects completed the POMS and the Structured Interview Guide for the Hamilton Depression Rating Scale--Seasonal Affective Disorders Version (SIGH-SAD) each week.

RESULTS

Good psychological adjustment was demonstrated by a significant decline in POMS factor scores for tension-anxiety (p = 0.005), fatigue (p < 0.0001), and confusion (p = 0.024) from baseline to Week 3, and a significant decline in SIGH-SAD depressive symptoms (p < 0.0001) during Weeks 1-3. This is attributed to high levels of paratelic dominance and low levels of neuroticism, and use of planful problem-solving as a coping strategy more frequently than other coping strategies.

CONCLUSIONS

Improved psychological functioning among polar expeditioners reflects a combination of psychosocial characteristics that facilitate successful adaptation to any stressful experience, as well as characteristics specifically adaptive for living in polar environments.

Acculturation as a risk factor for chronic disease among Cambodian refugees in the United States

Although the concept of acculturation originated within anthropology, in recent years it has assumed a prominent role within epidemiology as a risk factor for chronic disease. However, these studies often consider acculturation in structural terms, reflected in differences between groups assumed to lie along the same continuum, all moving in the same direction toward greater acculturation to the values and behaviors of the dominant society. This paper addresses how acculturation should be conceptualized when examining it as a potential risk factor for chronic disease and how it should be measured so that it becomes both theoretically and clinically meaningful. Four case studies of Cambodian refugees of San Diego, California are used to illustrate the following: (1) the importance of integrating an acculturation-as-process perspective with an acculturation-as-structure perspective; (2) viewing acculturation as both individual and group experience of conflict and negotiation between two systems of behavior and belief; (3) measuring it longitudinally and as narrative; and (4) understanding that rather than being an inherent health risk, it may also promote health by creating access to certain forms of health care unavailable in the country of origin and by contributing to the abandonment of risky health-related behaviors and the adoption of behaviors that promote good health.

Seasonal variation of depressive symptoms in Antarctica

Symptom characteristics and risk factors for seasonal variation in depressive symptoms were prospectively examined in 119 men and women who overwintered in Antarctica. Over a 12-month period, this cohort reported significant increases in their global depressive symptom scores as well as several individual symptoms associated with winter depression. Summer depression and marital status were significant independent predictors of winter depression. Factor analyses of summer and winter symptoms revealed a set of symptoms traditionally associated with the winter-over experience in a distinct factor not found in summer. These results indicate that even asymptomatic, clinically normal populations experience seasonal variation in mood in high-latitude environments. However, this seasonal variation may be the result of social isolation during the winter months rather than the prolonged absence of sunlight.

Does Beano prevent gas? A double-blind crossover study of oral alpha-galactosidase to treat dietary oligosaccharide intolerance

BACKGROUND

Beano, an over-the-counter oral solution of alpha-galactosidase, is used to prevent flatus and other gastrointestinal symptoms resulting from a high-fiber diet. The efficacy of this product, however, has not yet been adequately evaluated.

METHODS

Nineteen subjects were randomized into two groups and fed test meals of meatless chili. At the first test meal, group 1 received eight drops of alpha-galactosidase solution and group 2 received eight drops of placebo. After the meal, subjects were asked to keep a careful record of gastrointestinal symptoms, including occurrences of intestinal gas passage, for the next 6 hours. One week later, an identical test meal was served to each study subject and the solutions were reversed. Again subjects recorded their symptoms for the next 6 hours. Data were analyzed by means of paired t tests.

RESULTS

The number of flatulence events per hour was significantly less in the group treated with alpha-galactosidase than placebo over the 6-hour follow-up period (F = 2.87, P = .016). When the two groups were compared at each follow-up interval, this difference was statistically significant only for the 5th hour after ingesting the test meal (t = 2.19, P = .04). No differences between the two groups were found in the extent of bloating or pain following the meal.

CONCLUSIONS

Oral alpha-galactosidase solution is efficacious, at least in some patients, for the prophylaxis of gastrointestinal intolerance of oligosaccharides.

'Betelmania'. Betel quid chewing by Cambodian women in the United States and its potential health effects

Although an estimated 10% to 25% of the world's population chews betel quid, this practice is virtually unknown in the United States. Health care professionals coming into contact with immigrants and refugees from India, New Guinea, and Southeast Asia will increasingly notice this habit. Possible hazards associated with the chewing of the various ingredients of the quid include oral cancer and an addictive potential as strong as for cigarettes. We surveyed a group of Cambodian refugee women who are addicted to betel nut and its associated components. Participant-directed interviews uncovered some of the cultural meanings surrounding the ritual of preparing and using the betel quid and the role of culture in the beliefs and behaviors related to chemical addiction.

Low blood pressure and depression in older men: a population based study

OBJECTIVE

To determine if an association exists between low blood pressure and depressive symptoms in older men living in the community.

DESIGN

Cross sectional, population based study.

SETTING

Town of Rancho Bernardo, California, United States.

SUBJECTS

846 men aged 60-89 years. Comparisons between hypotensive, normotensive, and hypertensive groups were limited to 594 men not taking drugs for hypertension.

MAIN OUTCOME MEASURES

Mean scores on Beck depression inventory and prevalence of scores > or = 13.

RESULTS

Men with diastolic blood pressure < 75 mm Hg had significantly higher depression scores (mean scores 6.35 v 4.96; P < 0.001) and more categorical depression (7.6% v 1.8% with scores > or = 13; P < 0.01) than men with diastolic blood pressure levels between 75 and 85 mm Hg. Men with diastolic blood pressure levels > 85 mm Hg had higher depression scores than men with intermediate blood pressure levels (mean scores 5.85 v 4.96; P < 0.05). Men with diastolic hypotension scored significantly higher on both affective and somatic item subscales of the Beck depression inventory and on individual measures of fatigue, pessimism, sadness, loss of appetite, weight loss, and preoccupation with health. Low diastolic blood pressure was a significant predictor of both mean depression score and prevalence of categorical depression, independent of age and change in weight since the baseline visit. The presence of several chronic diseases was associated with depressed mood and higher blood pressure but not with low blood pressure.

CONCLUSION

The association of relatively low diastolic blood pressure with higher depressive symptom scores and rates of categorical depression was independent of age or weight loss. Since fatigue is a prominent symptom of depression, any association of low blood pressure with fatigue could reflect depressive disorders or clinically important depression.

Cigarette smoking behavior and beliefs of Hispanics in California

We examined the association between ethnicity and cigarette smoking beliefs and behavior in a 1990 random-digit dialing telephone survey of 3,164 Hispanic and 17,975 non-Hispanic white adults in California. Ethnic self-identification and native language were associated with the prevalence of current smoking in women but not in men. However, both male and female Hispanics smoked fewer cigarettes per day than their non-Hispanic counterparts. Hispanics who reported smoking in the past 12 months were more likely than non-Hispanics to have reached the action stage of cessation and to report an attempt to quit smoking. Spanish-speaking Hispanics were most likely to believe in the harmful effects of smoking, but also most likely to believe that smoking was not addictive, that they were not addicted to cigarettes, and that smoking is something everyone should try once. Cessation and prevention programs that target Hispanic populations must be especially sensitive to values and gender-specific acculturation processes that create a discrepancy between the desire to adopt the lifestyles of the dominant society and the recognition of the concomitant health-related risks.

Community patterns of psychiatric disorders after the Exxon Valdez oil spill

OBJECTIVE

This study examined the relationship between exposure to the Exxon Valdez oil spill and subsequent cleanup efforts and the prevalence of generalized anxiety disorder, posttraumatic stress disorder (PTSD), and depressive symptoms in 13 Alaska communities.

METHOD

A community survey of 599 men and women was conducted approximately 1 year after the spill occurred. Questions from the National Institute of Mental Health Diagnostic Interview Schedule were used to assess symptoms of generalized anxiety disorder and PTSD. The Center for Epidemiologic Studies Depression (CES-D) Scale was used to assess levels of depressive symptoms.

RESULTS

The post-spill (i.e., 1-year) prevalence of generalized anxiety disorder and PTSD for the study communities with all degrees of exposure was 20.2% and 9.4%, respectively. The prevalence of respondents with CES-D Scale scores above 16 and 18 was 16.6% and 14.2%, respectively. When compared with the unexposed group, members of the high-exposure group were 3.6 times as likely to have generalized anxiety disorder, 2.9 times as likely to have PTSD, 1.8 times as likely to have a CES-D Scale score of 16 and above, and 2.1 times as likely to have a CES-D Scale score of 18 and above. Women exposed to this event were particularly vulnerable to these conditions, and Alaska Natives were particularly vulnerable to depressive symptoms after the oil spill.

CONCLUSIONS

The results suggest that the oil spill's impact on the psychosocial environment was as significant as its impact on the physical environment. The Exxon Valdez experience suggests a number of implications for the mental health needs of disaster victims, particularly in primary care settings.

Plasma cholesterol and depressive symptoms in older men

In several clinical trials of interventions designed to lower plasma cholesterol, reductions in coronary heart disease mortality have been offset by an unexplained rise in suicides and other violent deaths. We have tried to find out whether depressive illness is related to low plasma cholesterol concentrations in men of 50 years and older. In 1985-87, Beck depression inventories were obtained from 1020 white men, aged 50-89 years, in the Rancho Bernardo, California, cohort. Disease history and behaviours were assessed by standard questionnaires. Plasma cholesterol and weight were measured at this time, as they had been in 1972-74. Among men aged 70 years and older, categorically defined depression was three times more common in the group with low plasma cholesterol (< 4.14 mmol/L) than in those with higher concentrations (5/31 [16%] vs 22/363 [6%]; p = 0.033). Depressive symptom scores correlated significantly and inversely with plasma cholesterol concentrations, even after adjustment for age, health status, number of chronic illnesses, number of medications, and exercise, as well as measured weight loss and change in plasma cholesterol in the previous 13 years. Our finding that low plasma cholesterol is associated with depressive symptoms in elderly men is compatible with observations that a very low total cholesterol may be related to suicide and violent death. Since cholesterol lowering in the general population is widely recommended, this observation warrants further investigation.

Going to extremes: the cultural context of stress, illness and coping in Antarctica

The question of whether the concept of adaptation remains useful in medical anthropology is examined in the context of the human experience in Antarctica. This experience is characterized by prolonged isolation, confinement, and exposure to extreme environmental conditions. Men and women who winter-over at scientific research stations often exhibit a complex of psychophysiological symptoms in response to these stressors. However, this experience also appears to provide long-term health benefits. It is argued that the psychological symptoms are themselves part of the process of coping and do not necessarily represent an inability to adapt to the extreme environment. Coping is viewed as a process of negotiation leading to a compromise between individual and group needs. The cultural systems of Antarctic research stations are both a product of this negotiation and a set of normative and pragmatic rules regulating this process. Further, this process fosters the acquisition of new strategies or resources for coping with subsequent stressful experiences.

Estrogen use and depressive symptoms in postmenopausal women

The potential antidepressant effects of estrogen replacement therapy were examined cross-sectionally in a population of 1190 women 50 years and older living in Rancho Bernardo, California. Of the total, 294 (24.7%) were currently using estrogen. Among women aged 50-59 years, those currently using noncontraceptive estrogen had a significantly higher rate of Beck Depression Inventory scores of 13 or higher than all untreated women of the same age and higher mean depressive symptom scores than women who had never used estrogen. However, after age 60, mean depressive symptom scores and rates of categorical depression increased significantly in the untreated women but not in the treated women. A similar pattern was found when depressive symptom measures of treated and untreated women were stratified by the number of years since last menstrual period. Greater depressive symptoms in currently treated versus untreated women aged 50-59 years may reflect treatment selection bias, as a higher proportion of symptomatic depressed climacteric women seek treatment. The decreased risk of depressive symptoms after age 60 may reflect a long-term benefit of estrogen replacement or the selective discontinuation of estrogen by depressed women. In this cohort, reports of hot flushes, moods, and insomnia as the reason for estrogen use fell in parallel with a decline in depressive symptoms with increasing age, suggesting that hormone replacement therapy provided relief of physical symptoms, ie, possible causes of psychological distress. Clinical trials are needed to confirm these observations and postulated explanations.

Ethnic differences in stress, coping, and depressive symptoms after the Exxon Valdez oil spill

This study assessed levels of depressive symptomatology in a household probability sample of Alaskan Native (N = 188) and Euro-American (N = 371) residents of 13 communities in Alaska. Our objective was to examine ethnic differences in both the association between depressive symptomatology and exposure to the Exxon Valdez oil spill and subsequent cleanup efforts, and in the role of family support as a moderator of exposure to this technological disaster. Level of exposure was significantly associated with mean Center for Epidemiological Studies-Depression Scale scores in both Natives (p less than .05) and Euro-Americans (p less than .01). Both ethnic groups also reported significant declines in traditional relations with increasing levels of exposure (p less than .001). However, Natives had a significantly higher mean Exposure Index score than Euro-Americans and were more likely to report working on cleanup activities, damage to commercial fisheries, and effects of the spill on subsistence activities. Depressive symptomatology was associated with reported participation in cleanup activities and other forms of contact with the oil in Natives, and reported damage to commercial fisheries, use of affected areas, and residence in a community in geographic proximity to the spill in Euro-Americans. Perceived family support was not directly associated with depressive symptoms in either ethnic group, but did serve to buffer the effects of exposure on depressive symptoms in Euro-Americans. The results suggest that cultural differences play an important role in determining the psychosocial impacts of a technological disaster, particularly with respect to exposure, appraisal of an event as stressful, perceived family support as a moderator of stress, and expression of depressive symptomatology.

Type 2 diabetes and depressive symptoms in older adults: a population-based study

The prevalence of depressive symptoms and its association with Type 2 (non-insulin-dependent) diabetes was examined in a population-based study of 1586 men and women aged 50 years or older. Men and women with previously diagnosed diabetes had significantly higher mean Beck Depression Inventory total, somatic subscale, and affective subscale scores than normal men and women and individuals with newly diagnosed diabetes. The age- and sex-adjusted rates of Inventory scores of 13 or greater among individuals with previously diagnosed diabetes was 3.7 times greater than the rates among individuals with newly diagnosed diabetes (p less than 0.05). Medication use and fasting plasma glucose were unrelated to symptom score. The number of other chronic conditions and age were significant independent predictors of depressive symptoms in all diabetic men and women. Results suggest that depressive symptoms in individuals with Type 2 diabetes may be related to awareness of diabetic condition in addition to poor health.

Suicides in active-duty enlisted Navy personnel

Cases of completed suicide among U.S. Navy enlisted personnel occurring from 1974 through 1985 were identified and compared with similar rates in the U.S. general population and in the U.S. Army. Although the Navy suicide rate was the lowest of the three groups, this rate increased between 1976 and 1983. This was in contrast to national and Army trends during the same period. Young white males in the apprentice/recruit and blue-collar occupations had the highest rates of completed suicide in the Navy. Recommendations for prevention and treatment are discussed.

Increasing incidence of varicella hospitalizations in United States Army and Navy personnel: are today's teenagers more susceptible? Should recruits be vaccinated?

Hospital records for 10,687 United States Army and Navy adult varicella (chickenpox) admissions were reviewed. Annual hospital admission rates for varicella increased more than fourfold in the active-duty army during 1980 to 1988 and more than 18-fold among active-duty navy enlisted personnel during 1975 to 1988. Fifty-seven percent of varicella admissions occurred in the most junior military members, aged 17 to 20. More than half of the total varicella admissions occurred in personnel with less than a year of military service. Multivariate analysis of the navy data confirmed increasing time-related trends of risk, suggesting a national temporal trend of increased varicella susceptibility in US teenagers and young adults. Administering a safe and effective varicella vaccine to army and navy recruits could prevent more than 7260 hospital-bed days during the first year of use.

Ten-year profile of infectious and parasitic disease hospitalizations in the U.S. Navy

Age-adjusted rates of total first hospital admissions of U.S. Navy enlisted personnel with diagnoses of infectious and parasitic diseases declined from a high of 112.9 per 10,000 person-years in 1977 to a low of 50.3 per 10,000 person-years in 1982. Ten specific diagnoses accounted for 78% of these hospitalizations. Eight diagnoses exhibited significant increases in rates over the study period. Improved medical care and prophylaxis, greater emphasis on outpatient care, changing social characteristics of Navy personnel, and changes in deployment theaters may account for the observed trends in hospitalization.

Psychosocial effects of adjustment in Antarctica: lessons for long-duration spaceflight

This paper examines the utility of remote, isolated Antarctic research stations as analogs for long-duration spaceflights from the perspective of psychosocial processes of adaptation and adjustment. Certain features of the physical and man-made environments found in Antarctica are similar to those that will be encountered in outer space. In both settings, men and women are likely to experience a number of physiological and psychological changes in response to the extreme environmental conditions and the prolonged isolation and confinement. Biomedical research in Antarctica provides an opportunity to study the causes of these changes and to develop strategies for reducing the risks to health and well-being before they pose a serious threat to crew safety and mission success. A number of lessons for long-duration spaceflight are examined, including screening and selection of personnel; training programs designed to facilitate individual adjustment and group adaptation and minimize group conflict; identification of optimal leadership characteristics for small, isolated groups; an understanding of social dynamics and group "microcultures" necessary for the organization and management of small but heterogeneous groups; organization of work activities; facility design; and support infrastructure.

Chronic illness and depressive symptoms in the elderly: a population-based study

A cross-sectional study of the distribution of depressive symptoms and association between depressed mood and chronic illness was conducted in a geographically defined population in southern California of 1617 men and women aged 65 years and older. The prevalence of depressed mood for the total population was 5.2%. Women exhibited a significantly higher mean depressive symptom score and a prevalence rate almost twice that of men. Depressive symptoms were associated with several risk factors in both sexes, including age, self-perception of current health status, number of reported chronic diseases and medications and amount of exercise. However, the relationship between physical illness and depressive symptoms appeared to differ by sex with respect to the nature of the disease or disability and the type of medication currently used. These findings indicate that the risk of depression does not diminish with age among the elderly as other studies have suggested.

The biocultural context of social networks and depression among the elderly

The association between the size and structure of social networks and the prevalence of depressive symptoms was examined in a population-based study of 1615 men and women age 65 years and older. Age was significantly associated with marital status, social network index quartile, and the social relationship to the primary source of support. Women and men differed with respect to current marital status, number of close friends and relatives, frequency of face-to-face contact, and participation in voluntary associations and religious institutions. Regardless of their marital status, women were also less likely than men to point to a spouse as their primary source of support. Beck Depression Inventory mean scores and rates of depressive symptoms were inversely associated with social network index and participation in voluntary associations and religious institutions for both men and women. Individuals with no primary source of support or who depended on a relative had significantly higher than expected mean scores and rates of depressive symptoms. Both social network index and social distance to primary source of support were independently associated with depression after controlling for age, sex, and number of chronic conditions. Participation in voluntary associations, social distance from primary source of support, church membership, and number of close friends were also significant independent predictors of depressive symptoms. Results indicate that depressive symptoms are inversely associated with the size of social networks. The structure of these networks, in turn, is influenced by biological factors such as age, physical disability, and mortality of network members, and by culturally-determined rules that define the individuals and institutions available for support. However, these rules appear to differ for men and women.

Viral hepatitis in the US Navy, 1975-1984

The epidemiology of viral hepatitis in US Navy enlisted personnel was reviewed for the years 1975-1984. Hospital discharge summaries of all active duty enlisted personnel admitted to a US Navy treatment facility were used for the study. From 1975 to 1984, total first hospitalizations for viral hepatitis declined from 128 per 100,000 personnel (95% confidence interval (Cl) 118-139) to 56 per 100,000 personnel (95% Cl 50-63). The highest incidence of acute viral hepatitis (115 per 100,000 personnel) was found in the youngest age groups aged 24 years and less. Risk factors for acute hepatitis included a previous hospitalization with either drug abuse (relative risk = 363) or a sexually transmitted disease (relative risk = 25) listed among the discharge diagnoses. Having a medical job classification was also associated with an increased risk of acute hepatitis. The steep decline in the incidence of viral hepatitis during this 10-year period may have been due to decreasing drug abuse in the US Navy. Immunization of high-risk groups in the US Navy with hepatitis B vaccine could be an effective policy for the prevention of acute viral hepatitis.