Disability in Older Adults 1: Prevalence,Causes, and Consequences

The effects of disability on an aging population's health and welfare are an important issue in gerontological research. The rapid growth of the elderly population and increases in longevity have led to an ongoing debate about whether longer lives can be matched by longer active lives that are free from disability. After a detailed review of current disability literature, the authors discuss the impact of disability in the elderly, defining disability and reviewing three classes of disability—physical, mental, and social. Both subjective and objective disability measures are described, and disability trends and prevalence rates are reviewed and compared cross culturally, by gender, by age, and over time. The path from chronic disease to disability is described and the consequences of living with disability are discussed in terms of family burdens and the increased need for medical care.     

The effect of thrombopoietin on the proliferation and differentiation of murine hematopoietic stem cells

In this study, we explored whether thrombopoietin (Tpo) has a direct in vitro effect on the proliferation and differentiation of long-term repopulating hematopoietic stem cells (LTR-HSC). We previously reported a cell separation method that uses the fluorescence-activated cell sorter selection of low Hoescht 33342/low Rhodamine 123 (low Ho/low Rh) fluorescence cell fractions that are highly enriched for LTR-HSC and can reconstitute lethally irradiated recipients with fewer than 20 cells. Low Ho/low Rh cells clone with high proliferative potential in vitro in the presence of stem cell factor (SCF) + interleukin-3 (IL-3) + IL-6 (90% to 100% HPP-CFC). Tpo alone did not induce proliferation of these low Ho/low Rh cells. However, in combination with SCF or IL-3, Tpo had several synergistic effects on cell proliferation. When Tpo was added to single growth factors (either SCF or IL-3 or the combination of both), the time required for the first cell division of low Ho/low Rh cells was significantly shortened and their cloning efficiency increased substantially. Moreover, the subsequent clonal expansion at the early time points of culture was significantly augmented by Tpo. Low Ho/low Rh cells, when assayed in agar directly after sorting, did not form megakaryocyte colonies in any growth condition tested. Several days of culture in the presence of multiple cytokines were required to obtain colony-forming units-megakaryocyte (CFU-Mk). In contrast, more differentiated, low Ho/high Rh cells, previously shown to contain short- term repopulating hematopoietic stem cells (STR-HSC), were able to form megakaryocyte colonies in agar when cultured in Tpo alone directly after sorting. These data establish that Tpo acts directly on primitive hematopoietic stem cells selected using the Ho/Rh method, but this effect is dependent on the presence of pluripotent cytokines. These cells subsequently differentiate into CFU-Mk, which are capable of responding to Tpo alone. Together with the results of previous reports of its effects on erythroid progenitors, these results suggest that the effects of Tpo on hematopoiesis are greater than initially anticipated.     

Frailty in older Mexican Americans

OBJECTIVES: To identify sociodemographic characteristics and health performance variables associated with frailty in older Mexican Americans. DESIGN: A prospective population-based survey. SETTING: Homes of older adults living in the southwest. PARTICIPANTS: Six hundred twenty-one noninstitutionalized Mexican-American men and women aged 70 and older included in the Hispanic Established Populations for Epidemiologic Study of the Elderly participated in a home-based interview. MEASUREMENTS: Interviews included information on sociodemographics, self-reports of medical conditions (arthritis, diabetes mellitus, heart attack, hip fracture, cancer, and stroke) and functional status. Weight and measures of lower and upper extremity muscle strength were obtained along with information on activities of daily living and instrumental activities of daily living. A summary measure of frailty was created based on weight loss, exhaustion, grip strength, and walking speed. Multivariable linear regression identified variables associated with frailty at baseline. Logistic regression examined variables predicting frailty at 1-year follow-up. RESULTS: Sex was associated with frailty at baseline (F=4.28, P=.03). Predictors of frailty in men included upper extremity strength, disability (activities of daily living), comorbidities, and mental status scores (Nagelkerke coefficient of determination (R(2))=0.37). Predictors for women included lower extremity strength, disability (activities of daily living), and body mass index (Nagelkerke R(2)=0.29). At 1-year follow-up, 83% of men and 79% of women were correctly classified as frail. CONCLUSION: Different variables were identified as statistically significant predictors of frailty in Mexican-American men and women aged 70 and older. The prevention, development, and treatment of frailty in older Mexican Americans may require consideration of the unique characteristics of this population.     

Hypertension in dialysis and kidney transplant patients

For the first time, the Canadian Hypertension Education Program has studied the evidence supporting blood pressure control in people requiring renal replacement therapy for end-stage kidney disease, including those on dialysis and with renal transplants. According to the Canadian Organ Replacement Registry’s 2008 annual report, there were an estimated 33,832 people with end-stage renal disease in Canada at the end of 2006, an increase of 69.7% since 1997. Of these, 20,465 were on dialysis and 13,367 were living with a functioning kidney transplant. Thus, it is becoming more likely that primary care practitioners will be helping to care for these complex patients. With the lack of large controlled clinical trials, the consensus recommendation based on interpretation of the existing literature is that blood pressure should be lowered to below 140/90 mmHg in hypertensive patients on renal replacement therapy and to below 130/80 mmHg for renal transplant patients with diabetes or chronic kidney disease.     

Adolescents with type 1 diabetes and risky behaviour

Aim: The aim of the student is to assess whether adolescents with type 1 diabetes mellitus (T1DM) in Italy differ from their healthy peers in regard to risky behaviour. Methods: Data were collected from 215 patients, aged 14 ± 2 years with a mean disease duration of 7 ± 5 years. The control group was comprised of 464 healthy adolescents recruited among high school students. Each patient completed an anonymous confidential questionnaire to determine the prevalence of sexual behaviour, alcohol and tobacco consumption, illicit drug use, and, among patients with diabetes and frequency of mismanagement related to diabetes care. Results: Compared with controls, subjects with diabetes showed a similar rate of sexual intercourse among males and lower rates among females (34.8% vs 35.5%, p NS and 29.4% vs 41.4%, p < 0.05, respectively). Males in the diabetes group reported a higher rate of tobacco use, whereas females showed similar or higher rates of use for every illicit drug studied. Among patients with diabetes, those who are engaged in risky behaviour showed a higher rate of treatment mismanagement (76% vs 34%, p < 0.01). Conclusion: Adolescents with T1DM are as likely as their healthy peers to engage in risky behaviour, indicating the potential benefit of anticipatory guidance concerning glycaemic control and increased risk of acute and chronic complications.     

Oligosaccharides in human milk during different phases of lactation

Twenty-one oligosaccharides of human milk were quantified by high-performance anion-exchange chromatography. Milk samples were collected from 18 mothers during the first 3 mo of lactation. The data show that the highest amount of all oligosaccharides is present at day 4 postpartum (20 g l⁻¹) and then decreases by about 20% at day 30 of lactation. The protective role played by these substances against different infectious agents, in different organs and systems of the breastfed baby, is emphasized.     

Emotional well-being predicts subsequent functional independence and survival

OBJECTIVE: To determine whether positive affect has an independent effect on functional status, mobility, and survival in an older Mexican American sample. DESIGN: A 2-year prospective cohort study. SETTING: Five Southwestern states: Texas, California, Arizona, New Mexico, and Colorado. PARTICIPANTS: A population-based sample of 2282 Mexican Americans aged 65 to 99 who reported no functional limitations at baseline interview. MEASUREMENTS: In-home interviews in 1993-1994 and again in 1995-1996 assessed demographic variables, health conditions, activities of daily living, performance-based mobility, survival, and a rating of positive and negative affect. RESULTS: In multivariate analyses, there was a direct relationship between positive affect scores at baseline and mobility, functional status, and survival 2 years later, controlling for functional status, sociodemographic variables, major chronic conditions, body mass index (BMI), smoking status, drinking status, and negative affect at baseline. Subjects with high positive affect were half as likely (odds ratio (OR) = 0.48; 95% confidence interval (CI) 0.29, 0.93) to become disabled in activities of daily living (ADLs), two-thirds as likely (OR = 0.64; 95% CI 0.51, 0.79) to have a slow walking speed, and half as likely (OR 0.53; 95% CI 0.30, 0.93) to have died during the 2-year follow-up compared to those with lower positive affect scores. CONCLUSIONS: Our results support the concept that positive affect, or emotional well-being, is different from the absence of depression or negative affect. Positive affect seems to protect individuals against physical declines in old age.     

The coeliac iceberg in Italy. A multicentre antigliadin antibodies screening for coeliac disease in school-age subjects

Background : Recent studies suggest that coeliac disease (CD) is one of the commonest, life-long disorders in Italy. The aims of this multicentre work were: (a) to establish the prevalence of CD on a nationwide basis; and (b) to characterize the CD clinical spectrum in Italy. Patients and methods : Fifteen centres screened 17201 students aged 6–15 years (68.6% of the eligible population) by the combined determination of serum IgG- and IgA-antigliadin antibody (AGA) test; 1289 (7.5%) were IgG and/or IgA-AGA positive and were recalled for the second-level investigation; 111 of them met the criteria for the intestinal biopsy: IgA-AGA positivity and/or AEA positivity or IgG-AGA positivity plus serum IgA deficiency. Results : Intestinal biopsy was performed on 98 of the 111 subjects. CD was diagnosed in 82 subjects (75 biopsy proven, 7 not biopsied but with associated AGA and AEA positivity). Most of the screening-detected coeliac patients showed low-grade intensity illness often associated with decreased psychophysical well-being. There were two AEA negative cases with associated CD and IgA deficiency. The prevalence of undiagnosed CD was 4.77 × 1000 (95% CI 3.79–5.91), 1 in 210 subjects. The overall prevalence of CD, including known CD cases, was 5.44 × 1000 (95% CI 4.57–6.44), 1 in 184 subjects. The ratio of known to undiagnosed CD cases was 1 in 7. Conclusions : These findings confirm that, in Italy, CD is one of the most common chronic disorders showing a wide and heterogeneous clinical spectrum. Most CD cases remain undiagnosed unless actively searched.     

Trends in length of stay, living setting, functional outcome, and mortality following medical rehabilitation

Context  Changes in reimbursement have reduced length of stay (LOS) for patients receiving inpatient medical rehabilitation. The impact of decreased LOS on functional status, living setting, and mortality is not known. Objective  To examine changes in LOS, functional status, living setting, and mortality in patients completing inpatient rehabilitation. Design  Retrospective cohort study from 1994 through 2001 using information submitted to the Uniform Data System for Medical Rehabilitation. Setting and Participants  Data were analyzed from 744 inpatient medical rehabilitation hospitals and centers located in 48 US states. A total of 148 807 patient records from 5 impairment groups (stroke, brain dysfunction, spinal cord dysfunction, other neurologic conditions, and orthopedic conditions) were examined. Patients’ mean age was 67.8 (SD, 15.8) years; the sample was 59% female and 81% non-Hispanic white. Main Outcome Measures  Discharge setting, follow-up living setting, change in functional status, and mortality. Results  Median LOS decreased from 20 to 12 days (P<.001) from 1994 to 2001. The proportional decrease in median LOS was greatest (42%) for patients with orthopedic conditions. Mean days to follow-up remained constant from 89 in 1994 to 90 in 2001. Functional status was clinically stable, while efficiency (functional status change divided by LOS) increased significantly (P<.001). Rates of discharge to home and living at home at follow-up remained stable, ranging from 81% to 93%. However, mortality at 80- to 180-day follow-up increased from less than 1% in 1994 to 4.7% in 2001. Conclusions  Length of stay for inpatient rehabilitation decreased substantially from 1994 to 2001. Effectiveness as measured by change in functional status did not change clinically, and living setting did not change. Efficiency for functional outcomes improved but mortality at follow-up increased.      

Neighbourhood composition and depressive symptoms among older Mexican Americans

STUDY OBJECTIVE: Research suggests that economically disadvantaged neighbourhoods confer an increased risk of depression to their residents. Little research has been reported about the association between ethnic group concentration and depression. This study investigated the association between neighbourhood poverty and neighbourhood percentage Mexican American and depressive symptoms for older Mexican Americans in the south western United States. DESIGN: A population based study of older non-institutionalised Mexican Americans from the baseline assessment (1993/94) of the Hispanic established population for the epidemiologic study of the elderly (H-EPESE) merged with 1990 census data. SETTING: Five south western states in the United States. PARTICIPANTS: 3050 Mexican Americans aged 65 years or older. MAIN RESULTS: There was a strong correlation between the percentage of neighbourhood residents living in poverty and the percentage who were Mexican American (r = 0.62; p<0.001). Percentage neighbourhood poverty and percentage Mexican American had significant and opposite effects on level of depressive symptoms among older Mexican Americans. After adjusting for demographic and other individual level factors, each 10% increase in neighbourhood population in poverty was associated with a 0.763 (95% CI 0.06 to 1.47) increase in CES-D score, while each 10% increase in Mexican American neighbourhood population was associated with a -0.548 (95% CI -0.96 to -0.13) unit decrease in CES-D score among older Mexican Americans residing in their neighbourhoods. CONCLUSIONS: The findings suggest a sociocultural advantage conferred by high density Mexican American neighbourhoods, and suggest the need to include community level factors along with individual level factors in community based epidemiological health studies.