Walking the dog: the effect of pet ownership on human health and health behaviors

pre-printThis analysis explores whether pet owners have better physical health outcomes, and if so, whether the positive physical health benefits are explained by better health behaviors that result from having to take care of the pet's physical needs. Data come from the National Health and Nutrition Examination Survey (NHANES), a representative sample of the non-institutionalized United States population. Analyses were limited to persons living alone (n=2474) in order to isolate primary pet caretakers from those merely living in a pet household. Results showed that pet owners, particularly dog and cat owners, had more positive physical health outcomes when compared to non pet owners or those owning other types of pets. Surprisingly, the effect of pet ownership was not mediated by health behaviors such as recreational walking. However, the health benefits of pet ownership were largely reduced once sociodemographic variables such as age, socioeconomic status, and residential location were controlled. The positive health effects of pet ownership appear to be primarily the result of selection, not increased physical activity associated with the active caretaking of pets

Obesity in America, 1960-2000: is it an age, period or cohort phenomenon?

ManuscriptIncreasing rates of obesity have sparked tremendous public concern because excess body weight is linked to a host of mortality, morbidity, and disability outcomes. Using five waves of data from the National Health and Nutrition Examination Survey (NHANES), this project privides a four-decade picture of body weight trends among American adults age 20-74. Specifically, this paper asks whether some birth cohorts have been more affected by these secular changes than others. It then considers the implications of these trends on future health and mortality. A series of graphical approaches provide the necessary background to estimate an age-period-cohort model of these trends. Results suggest that the Obesity Epidemic has occurred after the late 1970s, that the prevalence of obesity increases across the various stages of the adult life course, and that those cohorts born after 1915 have successfully higher rates of obesity at every stage of the life course

Feeling lonely vs. being alone: loneliness and social support among recently bereaved persons

pre-printObjectives: Despite increases in social support following widowhood, loneliness is among the most frequently reported challenges of bereavement. This analysis explores the dynamic relationship between social support and loneliness among recently bereaved older adults. Methods: Using longitudinal data from "Living After Loss" (n=328), latent growth curve modeling was used to estimate changes in loneliness and social support during the first year and a half of bereavement among older adults age 50+. Results: Both loneliness and social support declined over the first year and a half of bereavement. Greater social support was associated with lower levels of loneliness overall, but the receipt of social support did not modify one's expression of loneliness over time. Loneliness was more highly correlated with support from friends than family. Together, social support from both friends and family accounted for 36% of the total variance in loneliness. Discussion: There is conceptual and empirical overlap between the concepts of loneliness and social support, but results suggest that loneliness following widowhood cannot be remedied by interventions aimed only at increasing social support. Social support, especially that from friends, appears to be most effective if it is readily accessible and allows the newly bereaved an opportunity to express him/herself

Grief, depressive symptoms, and physical health among recently bereaved spouses

pre-printPurpose of Study: Widowhood is among the most distressing of all life events, resulting in both mental and physical health declines. This paper explores the dynamic relationship between physical health and psychological well-being among recently bereaved spouses. Design and Method: Using a sample of 328 bereaved persons who participated in the Living After Loss study, we modeled trends in physical health, somatic symptoms, and psychological well-being over the first year and a half of widowhood. The primary focus is whether physical health at the time of widowhood modifies psychological well-being over time. Results: There were considerable somatic symptoms during the earliest months of bereavement, but no major health declines over the first year and half of bereavement. Those in poor health had initially higher levels of grief and depressive symptoms, but the trajectories or changes over time were similar regardless of health status. Those with poor health at the time of widowhood had significantly higher risks of complicated grief and major depression disorder. Implications: Bereavement requires physical and emotional adjustment, but the psychological trajectory of bereavement may be somewhat universal. Bereavement support ought to include a focus on self-care and health promotion in addition to emotional support, especially since those with poor health initially may be most susceptible to prolonged and intense clinical distress

Parental divorce among young and adult children: a long-term quantitative analysis of mental health and family solidarity

Journal ArticleIn 2008, it was estimated that 40 percent of all marriages ended in divorce (U.S. Census, 2004) . Research has long suggested that the consequences of divorce can be profound for the children of divorced families (Amato, 2000). For example, children who experienced parental divorce were 50 percent more likely to develop health problems than children from intact two parent families (Angel, 1988; Tucker et al., 1997; Strohschei 2005). Similarly, children from divorced families also exhibit poorer academic performance (Astone & McLanahan, 1991; Wolfinger, 2003), delayed psychological development (Kurdek, Fine, & Sinclair,1994), strained relationships with family members (Hurre, 2006; Portman 2009), and poorer mental health (Ängarne-Lindberg, 2009). Some research has focused on the consequences of parental divorce as immediate or short-term consequences that are faced by the children - this is often referred to as a "crisis model"- whereas other research has documented the long-term effects of divorce - this is often referred to as the "chronic strain" model-, those consequences that persist for many years after parental divorce (Amato, 2000). Furthermore, scant research has attempted to isolate the potentially differential experiences of adult children (those who experience parental divorce as adults) compared to those who experience parental divorce earlier in the life course. About 20 percent of divorces occur in couples married over 15 years (Cooney, 1994), suggesting that parental divorce is not isolated to young children only. The purpose of this analysis is to identify whether children exhibited different types of consequences based on the age at which their parents divorced. Specifically, we explore whether the timing of parental divorce has long-term consequences on two distinct outcomes: the child's perceptions of family-solidarity and their mental health status later in life. These two outcomes were chosen because they represent a range of consequences involving both personal mental health and subsequent relationships with family

Humor, laughter, and happiness in the daily lives of recently bereaved spouses

Journal ArticleThe positive psychology movement has created more interest in examining the potential value of experiencing positive emotions (e.g., humor, laughter, and happiness) during the course of bereavement. This study of 292 recently widowed (5-24 weeks) men (39%) and women (61%) age 50 and over examined both the perceived importance of and actual experience of having positive emotions in their daily lives and how they might impact bereavement adjustments. We found that most of the bereaved spouses rated humor and happiness as being very important in their daily lives and that they were also experiencing these emotions at higher levels than expected. Experiencing humor, laughter, and happiness was strongly associated with favorable bereavement adjustments (lower grief and depression) regardless of the extent to which the bereaved person valued having these positive emotions

Birth cohort effects on abdominal obesity in the United States: the Silent Generation, Baby Boomers and Generation X

Background—Abdominal obesity predicts a wide range of adverse health outcomes. Over the past several decades, prevalence of abdominal obesity has increased markedly in industrialized countries like the U.S. No previous analyses, however, have evaluated whether there are birth cohort effects for abdominal obesity. Estimating cohort effects is necessary to forecast future health trends and understand past population-level trends. Methods—This analysis evaluated whether there were birth cohort effects for abdominal obesity for the Silent Generation (born 1925-1945), children of the Great Depression; Baby Boomers (born 1946-1964); or Generation X (born 1965-1980). Cohort effects for prevalence of abdominal obesity were estimated using the median polish method with data collected from the National Health and Nutrition Examination Survey between 1988 and 2008. Respondents were aged 20-74 years. Results—After taking into account age effects and ubiquitous secular changes, the Silent Generation and Generation X had higher cohort-specific prevalence of abdominal obesity than the Baby Boomers. Effects were more pronounced in women than men. Conclusions—This work presents a novel finding: evidence that the birth cohorts of the post-World War II Baby Boom appeared to have uniquely low cohort effects on abdominal obesity. The growing prosperity of the post-World-War II U.S. may have exposed the Baby Boom generation to lower levels of psychosocial and socioeconomic stress than previous or subsequent generations. By identifying factors associated with the Baby Boomers’ low cohort-specific sensitivity to the obesogenic environment, the obesity prevention community can identify early-life factors that can protect future generations from excess weight gain

A procedure to correct proxy-reported weight in the National Health Interview Survey, 1976–2002

<p>Abstract</p> <p>Background</p> <p>Data from the National Health Interview Survey (NHIS) show a larger-than-expected increase in mean BMI between 1996 and 1997. Proxy-reports of height and weight were discontinued as part of the 1997 NHIS redesign, suggesting that the sharp increase between 1996 and 1997 may be artifactual.</p> <p>Methods</p> <p>We merged NHIS data from 1976–2002 into a single database consisting of approximately 1.7 million adults aged 18 and over. The analysis consisted of two parts: First, we estimated the magnitude of BMI differences by reporting status (i.e., self-reported versus proxy-reported height and weight). Second, we developed a procedure to correct biases in BMI introduced by reporting status.</p> <p>Results</p> <p>Our analyses confirmed that proxy-reports of weight tended to be biased downward, with the degree of bias varying by race, sex, and other characteristics. We developed a correction procedure to minimize BMI underestimation associated with proxy-reporting, substantially reducing the larger-than-expected increase found in NHIS data between 1996 and 1997.</p> <p>Conclusion</p> <p>It is imperative that researchers who use reported estimates of height and weight think carefully about flaws in their data and how existing correction procedures might fail to account for them. The development of this particular correction procedure represents an important step toward improving the quality of BMI estimates in a widely used source of epidemiologic data.</p

Clarifying hierarchical age–period–cohort models: A rejoinder to Bell and Jones

Previously, Reither et al. (2015) demonstrated that hierarchical age–period–cohort (HAPC) models perform well when basic assumptions are satisfied. To contest this finding, Bell and Jones (2015) invent a data generating process (DGP) that borrows age, period and cohort effects from different equations in Reither et al. (2015). When HAPC models applied to data simulated from this DGP fail to recover the patterning of APC effects, B&J reiterate their view that these models provide “misleading evidence dressed up as science.” Despite such strong words, B&J show no curiosity about their own simulated data—and therefore once again misapply HAPC models to data that violate important assumptions. In this response, we illustrate how a careful analyst could have used simple descriptive plots and model selection statistics to verify that (a) period effects are not present in these data, and (b) age and cohort effects are conflated. By accounting for the characteristics of B&J's artificial data structure, we successfully recover the “true” DGP through an appropriately specified model. We conclude that B&Js main contribution to science is to remind analysts that APC models will fail in the presence of exact algebraic effects (i.e., effects with no random/stochastic components), and when collinear temporal dimensions are included without taking special care in the modeling process. The expanded list of coauthors on this commentary represents an emerging consensus among APC scholars that B&J's essential strategy—testing HAPC models with data simulated from contrived DGPs that violate important assumptions—is not a productive way to advance the discussion about innovative APC methods in epidemiology and the social sciences

Nitrated α–Synuclein Immunity Accelerates Degeneration of Nigral Dopaminergic Neurons

The neuropathology of Parkinson's disease (PD) includes loss of dopaminergic neurons in the substantia nigra, nitrated alpha-synuclein (N-alpha-Syn) enriched intraneuronal inclusions or Lewy bodies and neuroinflammation. While the contribution of innate microglial inflammatory activities to disease are known, evidence for how adaptive immune mechanisms may affect the course of PD remains obscure. We reasoned that PD-associated oxidative protein modifications create novel antigenic epitopes capable of peripheral adaptive T cell responses that could affect nigrostriatal degeneration.Nitrotyrosine (NT)-modified alpha-Syn was detected readily in cervical lymph nodes (CLN) from 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) intoxicated mice. Antigen-presenting cells within the CLN showed increased surface expression of major histocompatibility complex class II, initiating the molecular machinery necessary for efficient antigen presentation. MPTP-treated mice produced antibodies to native and nitrated alpha-Syn. Mice immunized with the NT-modified C-terminal tail fragment of alpha-Syn, but not native protein, generated robust T cell proliferative and pro-inflammatory secretory responses specific only for the modified antigen. T cells generated against the nitrated epitope do not respond to the unmodified protein. Mice deficient in T and B lymphocytes were resistant to MPTP-induced neurodegeneration. Transfer of T cells from mice immunized with N-alpha-Syn led to a robust neuroinflammatory response with accelerated dopaminergic cell loss.These data show that NT modifications within alpha-Syn, can bypass or break immunological tolerance and activate peripheral leukocytes in draining lymphoid tissue. A novel mechanism for disease is made in that NT modifications in alpha-Syn induce adaptive immune responses that exacerbate PD pathobiology. These results have implications for both the pathogenesis and treatment of this disabling neurodegenerative disease