Lianne M. Kurina

Depression and anxiety in people with inflammatory bowel disease.

STUDY OBJECTIVE To determine whether depression or anxiety co-occurs with ulcerative colitis (UC) or Crohns disease (CD) more often than expected by chance, and, if so, whether the mental disorders generally precede or follow the inflammatory bowel diseases (IBD). DESIGN Nested case-control studies using a database of linked hospital record abstracts. SETTING Southern England. MAIN RESULTS Both depression and anxiety preceded UC significantly more often than would be predicted from the control populations experience. The associations were strongest when the mental conditions were diagnosed shortly before UC, although the association between depression and UC was also significant when depression preceded UC by five or more years. Neither depression nor anxiety occurred before CD more often than expected by chance. However, depression and anxiety were significantly more common after CD; the associations were strongest in the year after the initial record of CD. UC was followed by anxiety, but not by depression, more often than expected by chance and, again, the association was strongest within one year of diagnosis with UC. CONCLUSIONS The concentration of risk of depression or anxiety one year or less before diagnosis with UC suggests that the two psychiatric disorders might be a consequence of early symptoms of the as yet undiagnosed gastrointestinal condition. The data are also, however, compatible with the hypothesis that the psychiatric disorders could be aetiological factors in some patients with UC. Most of the excess anxiety or depression diagnosed subsequent to diagnosis of IBD occurs during the year after IBD is diagnosed and the probable explanation is that the mental disorders are sequelae of IBD.

Sleep duration and all-cause mortality: a critical review of measurement and associations

PURPOSE Variation in sleep duration has been linked with mortality risk. The purpose of this review is to provide an updated evaluation of the literature on sleep duration and mortality, including a critical examination of sleep duration measurement and an examination of correlates of self-reported sleep duration. METHODS We conducted a systematic search of studies reporting associations between sleep duration and all-cause mortality and extracted the sleep duration measure and the measure(s) of association. RESULTS We identified 42 prospective studies of sleep duration and mortality drawing on 35 distinct study populations worldwide. Unlike previous reviews, we find that the published literature does not support a consistent finding of an association between self-reported sleep duration and mortality. Most studies have employed survey measures of sleep duration, which are not highly correlated with estimates based on physiologic measures. CONCLUSIONS Despite a large body of literature, it is premature to conclude, as previous reviews have, that a robust, U-shaped association between sleep duration and mortality risk exists across populations. Careful attention must be paid to measurement, response bias, confounding, and reverse causation in the interpretation of associations between sleep duration and mortality.

The influence of ants and water availability on oviposition behaviour and survivorship of a facultatively ant-tended herbivore

1. The lycaenid butterfly Hemiargus isola associates facultatively with the ant species Formica perpilosa in arid areas of south‐western North America. Ants solicit liquid food rewards from butterfly larvae as larvae feed on the host plant, Acacia constricta. Previous studies have shown that tending by F. perpilosa enhances larval growth and pupal survivorship.

Appendicectomy, tonsillectomy, and inflammatory bowel disease: a case-control record linkage study

Study objective: To determine whether appendicectomy and tonsillectomy are associated with ulcerative colitis (UC) or Crohns disease (CD); and, if so, whether the associations are related to age at operation. Design: Nested case-control studies using a longitudinal database of linked hospital and death record abstracts. Setting: Southern England. Patients: Statistical records of people diagnosed with UC, CD, or a control condition admitted to hospitals in a defined area. Main results: Appendicectomy under the age of 20 years was associated with a significantly reduced subsequent risk of UC (relative risk =0.48, 95% confidence interval 0.30 to 0.73). The association appeared strongest for appendicectomy between 10 and 14 years of age (relative risk =0.29, 95% CI 0.09 to 0.68). Appendicectomy at the age of 20 years and over was associated with an increased subsequent risk of CD (relative risk =1.92, 95% CI 1.58 to 2.32), largely confined to those people whose CD was diagnosed within a year of appendicectomy. Appendicectomy under 20 years of age, undertaken five years or more before case or control conditions, was suggestively associated with a reduced risk of CD (relative risk =0.71, 95% CI 0.47 to 1.03). Prior tonsillectomy was not associated with any increase or decrease of risk of either UC or CD. Conclusions: Appendicectomy is associated with a reduced risk of UC; and the association is specific to young age groups when the population risk of appendicitis is itself highest. The increased risk of CD after appendicectomy, at short time intervals between the two, is probably attributable to the misdiagnosis of CD as appendicitis.

Abortion and breast cancer: a case-control record linkage study

There is controversy about whether interruption of pregnancy, particularly if it is induced rather than spontaneous, increases the risk of breast cancer. Individual studies, and reviews summarising them, have given conflicting results.1 2 Recent guidelines from the UK Royal College of Obstetricians and Gynaecologists (http://www.rcog.org.uk) state that the evidence is inconclusive but that, when only those studies least susceptible to bias are considered, induced abortion does not seem to increase risk. Most studies of this association have been case-control interview studies. An important and much discussed consideration is whether such studies are inherently subject to reporting bias—that women with breast cancer may be more likely than control women to tell the interviewer if they have had an induced abortion when questioned about their reproductive history.3-5 If there are systematic reporting biases in interview studies, neither pooling of data across studies in meta-analysis nor further similar studies will …

Assessment of Sleep in the National Social Life, Health, and Aging Project

OBJECTIVES The relationship of sleep to health has been an active area of research in recent years, and the National Social Life, Health, and Aging Project (NSHAP) expanded sleep data collection in Wave 2 with enhanced core questions and a novel sleep module that included an objective measure of sleep duration and quality. METHOD A randomly selected one-third of Wave 2 participants and their spouses or coresident partners were invited to participate in the sleep module. Objective sleep data were collected using wrist actigraphy, an accelerometer that records an integrated measure of motion over short epochs (15 s each). This information is stored and subsequently analyzed to determine sleep and wake periods by epoch. Individuals were instructed to wear the actiwatches for 72 hr. Several sleep parameters were derived from the accelerometer. Individuals concurrently kept a sleep diary. RESULTS Sleep actigraphy data were successfully collected from 780 individuals. Many of the survey-based and the actigraph-estimated sleep parameters varied by age and gender. However, age and gender patterns often differed for sleep characteristics that were both asked and measured, such as sleep duration. DISCUSSION The survey and actigraphy data provide different information about sleep characteristics. The opportunity to examine actigraph-estimated sleep characteristics in a nationally representative sample of older adults allows novel analyses of the associations of sleep parameters with social and health data.

Sickle Cell Trait, Rhabdomyolysis, and Mortality among U.S. Army Soldiers

BACKGROUND Studies have suggested that sickle cell trait elevates the risks of exertional rhabdomyolysis and death. We conducted a study of sickle cell trait in relation to these outcomes, controlling for known risk factors for exertional rhabdomyolysis, in a large population of active persons who had undergone laboratory tests for hemoglobin AS (HbAS) and who were subject to exertional-injury precautions. METHODS We used Cox proportional-hazards models to test whether the risks of exertional rhabdomyolysis and death varied according to sickle cell trait status among 47,944 black soldiers who had undergone testing for HbAS and who were on active duty in the U.S. Army between January 2011 and December 2014. We used the Stanford Military Data Repository, which contains comprehensive medical and administrative data on all active-duty soldiers. RESULTS There was no significant difference in the risk of death among soldiers with sickle cell trait, as compared with those without the trait (hazard ratio, 0.99; 95% confidence interval [CI], 0.46 to 2.13; P=0.97), but the trait was associated with a significantly higher adjusted risk of exertional rhabdomyolysis (hazard ratio, 1.54; 95% CI, 1.12 to 2.12; P=0.008). This effect was similar in magnitude to that associated with tobacco use, as compared with no use (hazard ratio, 1.54; 95% CI, 1.23 to 1.94; P<0.001), and to that associated with having a body-mass index (BMI; the weight in kilograms divided by the square of the height in meters) of 30.0 or more, as compared with a BMI of less than 25.0 (hazard ratio, 1.39; 95% CI, 1.04 to 1.86; P=0.03). The effect was less than that associated with recent use of a statin, as compared with no use (hazard ratio, 2.89; 95% CI, 1.51 to 5.55; P=0.001), or an antipsychotic agent (hazard ratio, 3.02; 95% CI, 1.34 to 6.82; P=0.008). CONCLUSIONS Sickle cell trait was not associated with a higher risk of death than absence of the trait, but it was associated with a significantly higher risk of exertional rhabdomyolysis. (Funded by the National Heart, Lung, and Blood Institute and the Uniformed Services University of the Health Sciences.).

The social structure, stress, and women's health.

Of all the social determinants of health, gender is one of the most significant. Research spanning multiple disciplines indicates that women have higher rates of psychological distress, depression, and physical morbidity than men. According to the social stress model, group differences in mental and physical health partly reflect socially structured variations in exposure and vulnerability to stress. Thus, understanding the socioenvironmental factors that influence the number and types of stressors to which women are exposed is essential to understanding women’s health risks. The structural context in which women live has changed significantly over the past 30 years. Gender roles, family roles, and family structure have undergone dramatic shifts, many of which have been particularly relevant to women. These changes have important implications for the types of stressors women face and, ultimately, for their health and well-being. This chapter reviews recent research and theory on the impact of three key demographic patterns on the number and types of stressors to which women are exposed and the consequences of these stressors for their physical and mental health. These three factors that have significantly increased stress in women are: (1) women’s increased workforce participation, (2) the rise in divorce and single parenthood, and (3) the aging of the population. We also provide an overview of the psychosocial factors that influence women’s vulnerability to stress, discuss the biologic pathways through which socioenvironmental stressors affect women’s health and well-being, and explore disease outcomes of the stress process that are especially relevant to women. We conclude with a discussion of the ways in which interdisciplinary collaborations between sociologists, psychologists, and biomedical researchers can enhance our understanding of the processes through which stressors in the social environment affect women’s health. Correspondence: Kristi Williams, Department of Sociology, The Ohio State University, 42 Bricker Hall, 190 N. O v a l H a l l , C o l u m b u s , O H 4 3 2 1 0 . E m a i l : klw@mail.sociology.ohio-state.edu. Funding for this work was provided by NIH/NIA grant 2T32AG00243 to K. Williams (NIA Specialized Training: Demography and Economics of Aging) and Alfred P. Sloan Foundation, Center on Parents, Children and Work grant 2000–6-14 to L. M. Kurina. PROD. # GRF20418

Nitrogen fixation rates of Stereocaulon vulcani on young Hawaiian lava flows

Previous research has suggested thatnitrogen-fixing lichens can play an importantrole in the nitrogen cycle of early primarysuccessional systems and other extremeenvironments. In this study, we estimaterates of nitrogen fixation by anitrogen-fixing lichen, Stereocaulonvulcani, at 1500 m on the northeast slope ofMauna Loa volcano. Using microclimatemeasurements and a climate-driven model ofnitrogen fixation, we estimate that S.vulcani fixes between 0.2 and 0.45 kg N ha−1yr−1. We calculate that S. vulcanicould have derived 40% of its nitrogencontent from biological fixation.

Insomnia Symptoms and Actigraph-Estimated Sleep Characteristics in a Nationally Representative Sample of Older Adults

BACKGROUND Reports of insomnia symptoms are common among the elderly. However, little is known about the relationship between insomnia symptoms and objective assessments of sleep in the general population of older adults. We assessed concordance between insomnia symptoms and actigraphic sleep characteristics in a nationally representative sample of older Americans. METHODS In a national probability sample of 727 adults aged 62-91 years in 2010-2011 from the National Social Life, Health, and Aging Project, respondents were asked how often they (a) feel rested when they wake up, (b) have trouble falling asleep, (c) have trouble with waking up during the night, and (d) have trouble waking up too early and not being able to fall asleep again. Responses to these questions were compared to sleep characteristics estimated from three nights of actigraphy for the same individuals. Statistical analyses were adjusted for age, gender, race and ethnicity, income, assets, and education. RESULTS Feeling rested (Question (a), above) was not correlated with any actigraphy-estimated sleep characteristics. Questions (b)-(d) each had several significant correlations with the actigraphy metrics, but generally not with the specific objective sleep characteristics that each question intended to reference. In some cases, the associations were not in the expected direction. CONCLUSIONS Although three of four questions about insomnia symptoms were significantly associated with objectively estimated sleep characteristics, responses seem to be general indicators of sleep quality rather than reports of specific sleep characteristics.