In vivo detection of distal tumor glycolytic flux stimulated by hepatic ablation in a breast cancer model using hyperpolarized 13C MRI

PURPOSE

Hepatic thermal ablation therapy can result in c-Met-mediated off-target stimulation of distal tumor growth. The purpose of this study was to determine if a similar effect on tumor metabolism could be detected in vivo with hyperpolarized ¹³C MRI.

MATERIALS AND METHODS

In this prospective study, female Fisher rats (n = 28, 120-150 g) were implanted with R3230 rat breast adenocarcinoma cells and assigned to either: sham surgery, hepatic radiofrequency ablation (RFA), or hepatic RFA + adjuvant c-Met inhibition with PHA-665752 (RFA + PHA). PHA-665752 was administered at 0.83 mg/kg at 24 h post-RFA. Tumor growth was measured daily. MRI was performed 24 h before and 72 h after treatment on 14 rats, and the conversion of ¹³C-pyruvate into ¹³C-lactate within each tumor was quantified as lactate:pyruvate ratio (LPR). Comparisons of tumor growth and LPR were performed using paired and unpaired t-tests.

RESULTS

Hepatic RFA alone resulted in increased growth of the distant tumor compared to sham treatment (0.50 ± 0.13 mm/day versus 0.11 ± 0.07 mm/day; p < 0.001), whereas RFA + PHA (0.06 ± 0.13 mm/day) resulted in no significant change from sham treatment (p = 0.28). A significant increase in LPR was seen following hepatic RFA (+0.016 ± 0.010, p = 0.02), while LPR was unchanged for sham treatment (-0.048 ± 0.051, p = 0.10) or RFA + PHA (0.003 ± 0.041, p = 0.90).

CONCLUSION

In vivo hyperpolarized ¹³C MRI can detect hepatic RFA-induced increase in lactate flux within a distant R3230 tumor, which correlates with increased tumor growth. Adjuvant inhibition of c-Met suppresses these off-target effects, supporting a role for the HGF/c-Met signaling axis in these tumorigenic responses.

Acute Hemorrhagic Cholecystitis with Large Hemoperitoneum: Treatment with Microcoil Embolization and Subsequent Cholecystectomy

Hemorrhagic cholecystitis is a potentially deadly and difficult to recognize entity. It is associated with cystic artery pseudoaneurysm and is usually seen in the setting of acute calculous cholecystitis. We report two cases of hemorrhagic cholecystitis with arteriographic findings of cystic artery pseudoaneurysms that were successfully embolized using microcoils, facilitating subsequent cholecystectomy. Both cases had unusual presentations of gallbladder rupture with hemoperitoneum, the latter of which was atypical occurring in the absence of gallstones. We believe when hemorrhagic cholecystitis is suspected, a two-step therapeutic approach should be employed with embolization of the bleeding cystic artery followed by cholecystectomy. A comprehensive literature review and discussion of hemorrhagic cholecystitis will be provided.

Porphyromonas gingivalis-mediated Epithelial Cell Entry of HIV-1

HIV-1 relies on the host's cell machinery to establish a successful infection. Surface receptors, such as CD4, CCR5, and CXCR4 of T cells and macrophages, are essential for membrane fusion of HIV-1, an initiate step in viral entry. However, it is not well defined how HIV-1 infects CD4-negative mucosal epithelial cells. Here we show that there is a specific interaction between HIV-1 and an invasive oral bacterium, Porphyromonas gingivalis. We found that HIV-1 was trapped on the bacterial surface, which led to internalization of HIV-1 virions as the bacteria invaded CD4-negative epithelial cells. Both bacterial and viral DNA was detected in HeLa and TERT-2 cells exposed to the HIV-1-P. gingivalis complexes 2 hr after the initial infection but not in cells exposed to HIV-1 alone. Moreover, epithelial cell entry of HIV-1 was positively correlated with invasive activity of the P. gingivalis strains tested, even when the binding affinities of HIV-1 to these strains were similar. Finally, it was demonstrated that the viral DNA was integrated into the genome of the host epithelial cells. These results reveal a receptor-independent HIV-1 entry into epithelial cells, which may be relevant in HIV transmission in other mucosal epithelia where complex microbial communities can be found.

Environmental hazards and stress: evidence from the Texas City Stress and Health Study

BACKGROUND

Substantial research has suggested that exposure to environmental health hazards, such as polluting industrial activity, has deleterious effects on psychological and physiological well-being. However, one gap in the existing literature is comparative analysis of objective and subjective exposure's relative association with various measurable outcomes of exposure.

METHODS

These relationships were explored within a community sample of 2604 respondents living near a large petrochemical complex in Texas City, Texas, USA. Objective exposure was investigated using distance of residence from a cluster of petrochemical plants and subjective exposure using residents' concern about potential health effects from those plants. Regression models were then used to examine how each type of exposure predicts perceived stress, physiological markers of stress and perceived health.

RESULTS

Results suggest that objective exposure was associated primarily with markers of physiological stress (interleukin-6 and viral reactivation), and subjective exposure (concern about petrochemical health risk) was associated with variables assessing perceived health.

CONCLUSIONS

From the analysis, it can be inferred that, in the context of an environmental hazard of this type, subjective exposure may be at least as important a predictor of poor health outcomes as objective exposure.

Perceived health change in the aftermath of a petrochemical accident: an examination of pre-accident, within-accident, and post-accident variables

BACKGROUND

Little research has been conducted on changes in perceived health after an industrial accident. Using data from an ongoing survey on stress and health in a petrochemical complex in Texas City, Texas, the associations of a petrochemical accident with perceived health changes were examined.

METHODS

The mean changes in perceived mental and physical health across pre-accident, within-accident, and post-accident categories were compared. The association of these categorical variables with the change in perceived mental and physical health using multiple regression was also examined.

RESULTS

Significant declines in both perceived mental and physical health were observed for the sample. Regression analyses showed that middle age, lower education level and reported damage in the neighbourhood were associated with decreases in perceived mental health. Lower education level, explosion impact, and distance from the explosion site were associated with decreases in perceived physical health.

CONCLUSIONS

These results indicate that both pre-accident and within-accident variables, such as education level and explosion impact, are associated with decreases in perceived physical and mental health. Even a modest event within the range of accidents and disasters was shown to be associated with negative health outcomes for a population-based sample.

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.

The Relationship Between Blood Pressure and Mortality in the Oldest Old

OBJECTIVES

To explore the relationship between systolic and diastolic blood pressure and risk of 6-year, all-cause mortality in men and women age 65 to 84 versus those 85 and older.

DESIGN

A population-based longitudinal study.

SETTING

This study was conducted at four different sites: East Boston, Massachusetts; New Haven, Connecticut; two rural counties in Iowa; and Piedmont, North Carolina.

PARTICIPANTS

12,802 community-dwelling persons age 65 and older.

MEASUREMENTS

Baseline measurements collected include demographics, self-reported chronic medical conditions, blood pressure measurements, medications, health habits, and hospitalizations.

RESULTS

Unadjusted actuarial survival analyses show that men age 65 to 84 years with systolic blood pressure < 130 mmHg have significantly lower mortality compared with those with systolic blood pressure > or = 180 mmHg (P < .0001). In contrast, men 85 and older with systolic blood pressure > or = 180 mmHg have significantly lower mortality compared with those with systolic blood pressure < 130 mmHg (P < .0001). In Cox proportional hazards analyses controlling for other predictors of survival, the hazard of death associated with each 10-mmHg increase in systolic blood pressure is positively associated among men age 65 to 84 years and negatively associated among men age 85 and older (Hazard ratio and 95% confidence interval (CI): 1.04 (1.01, 1.07) for younger men vs 0.92 (0.86, 0.99) for older men). Among women age 65 to 84, the hazard of death significantly increased with increase in systolic blood pressure (P < .0001), while there was no relationship between level of systolic blood pressure and survival in women 85 and older. Both men 65 to 84 years old and those 85 and older showed a negative relationship between diastolic blood pressure and all-cause mortality (Hazard ratio 0.93, 95% CI (0.88-0.97) for men age 65-84 years, and Hazard ratio 0.90, 95% CI 0.80-1.02 for men 85 and older).

CONCLUSION

In men age 85 and older, higher systolic blood pressure is associated with better survival.

The use of herbal medicine by older Mexican Americans

BACKGROUND

Little is known about use of herbal medicines by older Mexican Americans. The objective of this study was to determine the characteristics among older Mexican Americans that correlate with use of herbal medicines.

METHODS

We administered a cross-sectional regional sample survey, the 1993-1994 Hispanic Established Populations for the Epidemiologic Study of the Elderly of Mexican Americans, by in-home interviews of noninstitutionalized older Mexican Americans age 65 and over living in Texas, New Mexico, Colorado, Arizona, and California.

RESULTS

The use of herbal medicine in the 2 weeks prior to the interview was reported by 9.8% of the sample. Chamomile and mint were the two most commonly used herbs. Users of herbal medicines were more likely to be women, born in Mexico, over age 75, living alone, and experiencing some financial strain. Having arthritis, urinary incontinence, asthma, and hip fracture were also associated with an elevated use of herbal medicines, whereas heart attacks were not. We found that herbal medicine use was substantially higher among individuals reporting any disability in activities of daily living, poor self-reported health, and depressive symptoms. Herbal medicine use was associated with the use of over-the-counter medications but not with prescription medications. Herbal medicine use was particularly high among respondents who had over 24 physician visits during the year prior to interview.

CONCLUSIONS

Herbal medication use is common among older Mexican Americans, particularly among those with chronic medical conditions, those who experience financial strain, and those who are very frequent users of formal health care services.

Clinical significance of falling blood pressure among older adults

We assessed the prevalence of falling blood pressure among older adults and its relationship to subsequent outcomes, using public use data from four sites of the Established Populations for Epidemiologic Studies of the Elderly. Seventeen percent of subjects had a decrease in systolic blood pressure of 20 mm Hg or greater and 22% had a decrease in diastolic blood pressure of 10 mm Hg or greater between year 0 and year 3. Falling systolic and diastolic blood pressure was associated with increased all-cause mortality (OR 1.5, 95% CI 1.3, 1.7), cardiovascular mortality (OR 1.6, 95% CI 1.3, 1.9) and all cardiovascular events (OR 1.4, 95% CI 1.2, 1.6) in the subsequent 3 years (years 4 to 6). Increasing amount of fall in blood pressure was associated with increasing risk of mortality. The magnitude of effect of falling blood pressure on adverse outcomes declined and became nonsignificant after adjusting for comorbidity and functional status at baseline. Thus, falling blood pressure is common among older adults and is a marker for underlying poor health and subsequent mortality.

Increase of chemotherapy use in older women with breast carcinoma from 1991 to 1996

BACKGROUND

There is little population-based information available on the actual use of chemotherapy and how closely this use mirrors consensus recommendations. The authors hypothesized that given the relative stability of consensus conference recommendations on chemotherapy use during the period 1991-1996 the patterns of use would more closely approximate consensus recommendation over time.

METHODS

The authors studied women who received a diagnosis of Stage I-IV (American Joint Committee on Cancer staging) breast carcinoma at age 65 years and older from 1991 through 1996, using the SEER cancer registry cases linked with Medicare claims.

RESULTS

Overall, women whose disease was diagnosed in 1996 had a 30% higher chance of receiving chemotherapy than those in 1991, after controlling for changes in tumor size, stage, and other factors. The use of chemotherapy was strongly influenced by age, with women age 65-69 years more than twice as likely to receive it as were women 70 years and older. The increase over time in chemotherapy depended on both tumor stage and patient age. For Stage I tumor, there was no increase in chemotherapy for any age. For Stage II, the increase was limited to younger women, whereas for Stage III and IV it was observed in women age 70 years and older.

CONCLUSIONS

There was a significant increase of chemotherapy use over time from 1991 to 1996 in women age 65 years and older with breast carcinoma. The increase was limited to younger women and those with advanced stage at diagnosis. Thus, consensus recommendations and community practice seemed to mirror each other over time.

Chronic rheumatologic symptoms in a tri-ethnic sample of men and women aged 75 and older

BACKGROUND

The high prevalence of musculoskeletal symptoms in elderly persons tends to obscure the recognition of specific medical conditions. The purpose of this study is to describe the prevalence of chronic rheumatologic symptoms and the associated measures of health status in an older population.

METHODS

This is a cross-sectional study of 507 noninstitutionalized tri-ethnic men and women aged 75 and older living in Galveston County, Texas. A home interview collected data on demographics, chronic medical conditions, cognition, depression, and functional status. Site, severity, and duration of rheumatologic symptoms such as morning stiffness, body tenderness, and body aching in the past month were also collected.

RESULTS

There was a high prevalence of nonspecific rheumatologic symptoms such as morning stiffness (32% in the shoulder girdle, 31% in the hip girdle), tenderness to touch (9%), and generalized body aching (11%) in the study population. Twenty-one percent of the subjects reported either bilateral shoulder or hip girdle stiffness or tenderness lasting more than 30 minutes almost every day or every day or generalized body aching most of the time during the past month. Age-, gender-, and ethnicity-adjusted multivariate analyses showed that more than three self-reported chronic medical conditions, poor or fair self-reported health, impairment in instrumental activities of daily living (IADL), and the presence of depressive or anxiety symptoms were associated with the presence of these chronic rheumatologic symptoms.

CONCLUSION

Chronic rheumatologic symptoms are common in people aged 75 and older. Such symptoms are markers for underlying poor health and for anxiety and depression among older subjects.

Impact of arthritis on disability among older Mexican Americans

OBJECTIVE

To estimate the impact of self-reported diagnosis of arthritis at baseline on the two year incidence of limitation in activities of daily living and instrumental activities of daily living in initially non-disabled Mexican-American elderly.

DESIGN

Longitudinal study. SETTING Southwestern United States (Texas, New Mexico, Colorado, Arizona and California).

SUBJECTS

A probability sample of 2,167 non-institutionalized Mexican-American men and women, aged 65 or older.

MEASURES

Having ever been told by a doctor that a subject had arthritis, Activities of Daily Living (ADL), Instrumental Activities of Daily Living (IADL), depressive symptomatology, presence of chronic diseases (diabetes mellitus, heart attack, stroke, cancer), and body mass index (BMI).

RESULTS

Among non-disabled persons at baseline, 11.2% of subjects with arthritis reported at least one ADL limitation after two years, compared to 6.9% of subjects without arthritis. Similarly, among non-disabled persons at baseline, 34.7% of subjects with arthritis reported at least one IADL limitation after two years, compared to 27.0% of subjects without arthritis. In logistic regression analysis, depression, diabetes, and arthritis were found to be predictive of the development of ADL disability, controlling for sociodemographic variables. Depression was the only condition that significantly predicted IADL disability.

CONCLUSIONS

Subjects with arthritis were more likely to develop ADL and IADL disability over a two-year period than those without arthritis.

Impact of pain on disability among older Mexican Americans

BACKGROUND

Joint pain is a very common complaint among elderly persons and may lead to functional disability. The purpose of this study is to estimate the prevalence of self-reported pain on weight bearing and its impact on the 2-year incidence of limitation in lower-body activities of daily living (ADL) in initially nondisabled Mexican American elderly subjects.

METHODS

We studied a probability sample of 2167 noninstitutionalized Mexican American men and women aged 65 or older residing in five Southwestern states. Subjects were asked about pain on weight bearing, ADL, depressive symptomatology, and the presence of chronic diseases. The body mass index was computed using measured height and weight. Finally, a three-task (tandem balance, 8-foot walk, and repeated chair stands), performance-based, lower-body function test was performed.

RESULTS

The overall prevalence of pain on weight bearing in the sample was 31.9%, with 37.7% for women versus 24.0% for men (p <.001). The most prevalent sites of pain were knees (14.7%), followed by ankle/feet (12.1%). In a logistic regression analysis, pain was a significant independent predictor of subsequent disability and of the inability to perform tandem balance, 8-foot walk, and repeated chair stands.

CONCLUSIONS

Pain on weight bearing is prevalent among older Mexican Americans and is a major independent risk factor for subsequent disability.

The association between emotional well-being and the incidence of stroke in older adults

OBJECTIVE

Individuals with high levels of depressive symptoms have an increased risk of many illnesses, including stroke. Measures of depressive symptoms include questions about the presence of negative affect, such as sadness, as well as the absence of positive affect, such as happiness and optimism. We assessed whether positive or negative affect, or both, predicted risk of stroke.

METHODS

Data were from a 6-year prospective cohort study of a population-based sample of 2478 older whites and blacks from five counties in North Carolina who reported no history of stroke at the baseline interview. Baseline, in-person interviews were conducted to gather information on sociodemographic, psychosocial, and health-related characteristics of subjects. Thereafter interviews were conducted annually for 6 years.

RESULTS

Increasing scores on the modified version of the Center for Epidemiological Studies Depression Scale (CES-D) were significantly associated with stroke incidence for the overall sample (relative risk [RR] = 1.04 for each one-point increase, 95% confidence interval [CI] = 1.01-1.09) over the 6-year follow-up period after adjusting for sociodemographic characteristics, blood pressure, body mass index, smoking status, and selected chronic diseases. Positive affect score demonstrated a strong inverse association with stroke incidence (RR = 0.74, 95% CI = 0.62-0.88).

CONCLUSIONS

Increasing scores on the modified CES-D are related to an increased risk of stroke, whereas high levels of positive affect seem to protect against stroke in older adults.

Patterns of use of chemotherapy for breast cancer in older women: findings from Medicare claims data

PURPOSE

There is little population-based information available on the use of chemotherapy in women with breast cancer. This study describes the use of chemotherapy through analysis of Medicare claims and determines the correlates of chemotherapy use.

PATIENTS AND METHODS

We used the merged Surveillance, Epidemiology, and End Results-Medicare database and identified women > or = 65 years of age diagnosed with breast cancer in 1991 and 1992. Chemotherapy was ascertained from Medicare claims through procedure codes for chemotherapy made within 24 months of the diagnosis.

RESULTS

In women with stages I, II, III, and IV breast cancer, the percentage receiving chemotherapy within 24 months of diagnosis was 5.1%, 19.5%, 33.9%, and 35.2%, respectively. Most women receiving chemotherapy had two to 12 claims; the median number was eight. Use of chemotherapy decreased significantly with age across all tumor stages; eg, in women with stage III cancer, the use of chemotherapy declined from 49% in those aged 65 to 69 years to 10% in those > or = 80 years old. In a multivariate analysis, there was little variation by ethnicity. Chemotherapy use was highest (70%) in women aged 65 to 69 years with node-positive and estrogen receptor-negative tumors and lowest (5%) in those with node-negative and estrogen receptor-positive tumors. Compared with those without comorbid diseases, patients with a comorbidity score of 2 had significantly lower use of chemotherapy.

CONCLUSION

Medicare claims data seem to provide valuable information on the use of chemotherapy for breast cancer in older women. However, external validation of the accuracy and completeness of these data is required before any firm conclusion can be drawn.

Spectroscopic evidence for amyloid-like interfacial self-assembly of hydrophobin Sc3

Amphipathic fungal proteins called hydrophobins are able to self-assemble into insoluble supramolecular structures at hydrophobic/hydrophilic interfaces, but the molecular mechanism and underlying protein conformation changes are not known. Secondary-structure prediction indicated that hydrophobin Sc3 is an all-beta protein. Many amyloidogenic proteins self-assemble into insoluble amyloid fibrils while undergoing a change to an all-beta conformation. In this study we show that two dyes, thioflavin T, and Congo red, which are widely used for specific detection of stacked beta sheets, interact with Sc3 assemblies in the same way as with the amyloid beta-sheet fibrils. We conclude that Sc3, and probably other hydrophobins too, self-assemble at interfaces in the same manner as amyloidogenic proteins, i.e., through beta-sheet stacking.

Prevalence of arthritis in older Mexican Americans

OBJECTIVE

This study examines the prevalence of self-reported physician-diagnosed arthritis and arthritis symptoms and their relationship to functional limitations in Mexican American elderly.

METHODS

We conducted a cross-sectional study using a probability sample of 2,873 non-institutionalized Mexican American men and women aged 65 or older, residing in the southwestern United States. Measures included self-reported physician-diagnosed arthritis, morning pain or stiffness, pain when standing, global health rating, activities of daily living (ADL), instrumental activities of daily living (IADL), depressive symptoms, presence of chronic diseases (diabetes mellitus, hypertension, heart attack, stroke), and body mass index. The Mantel-Haenszel chi-square statistic was used to test differences by arthritis status, and a logistic regression model was used to predict the odds of having arthritis.

RESULTS

The overall prevalence of self-reported physician-diagnosed arthritis in the sample was 40.8 percent, 50.0 percent among women and 28.8 percent among men (P < 0.001). Morning pain or stiffness was reported by 37.7 percent of respondents and pain when standing or walking by 31.9 percent. All comorbid conditions, and both IADL and ADL limitations, were more prevalent in those with arthritis than in those without arthritis. Female sex and several medical conditions were independently associated with self-reported arthritis.

CONCLUSIONS

Self-reported physician-diagnosed arthritis is common among older Mexican Americans. Functional limitation and disability are more prevalent among subjects with arthritis than among those without arthritis.

Accuracy and completeness of Medicare claims data for surgical treatment of breast cancer

BACKGROUND

Although a number of studies have used Medicare claims data to study trends and variations in breast cancer treatment, the accuracy and completeness of information on surgical treatment for breast cancer in the Medicare data have not been validated.

OBJECTIVES

This study assessed the accuracy and completeness of Medicare claims data for breast cancer surgery to determine whether Medicare claims can serve as a source of data to augment information collected by cancer registries.

METHODS

We used the Surveillance, Epidemiology and End Results (SEER) Cancer Registry-Medicare data and compared Medicare claims on surgery with the surgery recorded by the SEER registries for 23,709 women diagnosed with breast cancer at > or =65 years of age from 1991 through 1993.

RESULTS

More than 95% of women having mastectomies according to the Medicare data were confirmed by SEER. For breast-conserving surgery, 91% of cases were confirmed by SEER. The Medicare physician services claims and inpatient claims were approximately equal in accuracy on type of surgery. The Medicare outpatient claims were less accurate for breast-conserving surgery. In terms of completeness, when the 3 claims sources were combined, 94% of patients receiving breast cancer surgery according to SEER were identified by Medicare.

CONCLUSIONS

The combined Medicare claims database, which includes the inpatient, outpatient, and physician service claims, provides valid information on surgical treatment among women known to have breast cancer. The claims are a rich source of data to augment the information collected by tumor registries and provide information that can be used to follow long-term outcomes of Medicare beneficiaries.

An approach to identifying incident breast cancer cases using Medicare claims data

This study developed and evaluated a method for ascertaining a newly diagnosed breast cancer case using multiple sources of data from the Medicare claims system. Predictors of an incident case were operationally defined as codes for breast cancer-related diagnoses and procedures from hospital inpatient, hospital outpatient, and physician claims. The optimal combination of predictors was then determined from a logistic regression model using 1992 data from the linked SEER registries-Medicare claims data base and a sample of noncancer controls drawn from the SEER areas. While the ROC curve demonstrates that the model can produce levels of sensitivity and specificity above 90%, the positive predictive value is comparatively low (67-70%). This low predictive value is largely the result of the model's limitation in distinguishing recurrent and secondary malignancies from incident cases and possibly from the model identifying true incident cases not identified by SEER. Nevertheless, the logistic regression approach is a useful method for ascertaining incident cases because it allows for greater flexibility in changing the performance characteristics by selecting different cut-points depending on the application (e.g., high sensitivity for registry validation, high specificity for outcomes research). It also allows us to make specific adjustments to population based estimates of breast cancer incidence with claims.

Obesity and health conditions in elderly Mexican Americans: the Hispanic EPESE. Established Population for Epidemiologic Studies of the Elderly

The objective of this analysis was to determine the prevalence of obesity and its association with selected medical conditions in a non-institutionalized elderly Mexican-American population. Data employed are from a representative sample of 3050 elderly Mexican Americans from the five Southwestern states: Texas, California, Colorado, New Mexico, and Arizona. Complete Body Mass Index (BMI) data were available for 2769 individuals. The in-home survey obtained socio-demographic data, anthropometric measurements, including height and weight, blood pressure readings, self-reported health conditions and depressive symptomatology. It was found that 23% of men and 35% of women were obese (BMI > or =30 kg/m2). Using a weighted logistic regression model, a BMI of > or =26 kg/m2 was associated with a significantly higher risk of diabetes; a BMI of > or =30 kg/m2 was significantly associated with arthritis and measured hypertension and a BMI<22 kg/m2 was associated with a higher likelihood of self-reported cancer. In addition, the prevalence of obesity was found to be much higher in this elderly Mexican-American population than in the general population.

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.

Relationship between low blood pressure and depressive symptomatology in older people

OBJECTIVES

To determine if low blood pressure is associated with a definable constellation of somatic and psychological symptoms in older persons.

DESIGN

A population-based study.

SETTING

In-home interviews in five southwestern states.

PARTICIPANTS

A total of 2723 Mexican Americans aged 65 or older not living in institutions.

MEASURES

Blood pressure, Center for Epidemiologic Studies Depression Scale (CES-D), global self-rating of health, and self-esteem.

RESULTS

Bivariate analyses indicate a significant relationship between low blood pressure and increased depressive symptomatology; for example, systolic hypotensive subjects scored a CES-D mean of 12.07 +/- .67 compared to 8.99 +/- .95 for normotensives (P < .01). Regression analyses supported these findings when controlling for confounders such as gender, age, and use of antihypertensive medications. Subjects with low blood pressure also scored lower on self-esteem and global self-reported health and reported more days waking up feeling tired.

CONCLUSIONS

These data support the existence of a relationship between low blood pressure and higher levels of depressive symptomatology as well as a constellation of somatic and psychosocial symptoms.

Ethnic variation in attitudes toward hypertension in adults ages 75 and older

BACKGROUND

Although critical to the management of hypertension, the attitudes of geriatric patients and possible ethnic group differences in attitudes concerning the disease are poorly understood.

METHODS

Data from a 1995-1996 population-based survey of 507 Hispanic American, African American, and non-Hispanic white adults ages 75 and older were used to assess ethnic differences in perceptions regarding the cause, prevention, and treatment of hypertension, as well as associations between perceptions and use of preventive health services.

RESULTS

African Americans were more likely to attribute hypertension to health behaviors and stress. In contrast, Hispanic Americans were more likely consider the disease a normal part of aging, whereas non-Hispanic whites were more likely to attribute hypertension to heredity or mechanistic causes. Non-Hispanic whites were less likely to perceive hypertension as preventable, whereas Hispanic Americans were less likely to feel that hypertension was treatable. The odds of having a primary care physician, blood pressure checked, or glaucoma checked were lower among older African Americans and Hispanic Americans than older non-Hispanic whites. The odds of having had a recent physical and of emergency room use were higher among African Americans and lower among Hispanic Americans, in relation to non-Hispanic whites.

CONCLUSION

Ethnic differences regarding hypertension were clearly evident in this sample of older adults. In addition, attitudes regarding the cause and treatment of hypertension were found to be associated with both the use and the underuse of preventive health services in all three ethnic groups.

Temporal and regional variation in the use of breast-conserving surgery and radiotherapy for older women with early-stage breast cancer from 1983 to 1995

BACKGROUND

Authorities recommend radiation therapy after breast-conserving surgery for breast cancer. Numerous studies have reported that older women diagnosed with breast cancer are less likely to receive radiation after breast-conserving surgery. It is unclear how care of older women with breast cancer has changed over time.

METHODS

Women with local or regional stage breast cancer diagnosed between 1983-1995 were identified from the Surveillance, Epidemiology, and End Results (SEER) Cancer Registries. The treatment information in SEER includes type of surgical procedures and receipt of radiation therapy.

RESULTS

There were small increases in the percentage of women receiving breast-conserving surgery during the 1980s followed by substantial increases in the 1990s. Age was a major factor in determining receipt of radiation therapy after breast-conserving surgery. A large increase in use of radiotherapy after surgery was observed in women aged > or = 75, from below 30% in 1983 to over 50% in 1995. Women aged > or = 75 diagnosed in 1992-1995 were 1.76 and 2.34 times more likely to receive radiation for local and regional stage respectively, as compared to those in 1983-1987. There was no increase in use of radiation for women aged < 65.

CONCLUSIONS

There has been a substantial increase in use of breast-conserving surgery and in receipt of radiation therapy after breast-conserving surgery in older women. However, there was a net increase in the percentage of all women with breast cancer who received this surgery without radiotherapy, due to the large increase in the overall percentage of women receiving this surgery.

Aging versus disease: the opinions of older black, Hispanic, and non-Hispanic white Americans about the causes and treatment of common medical conditions

BACKGROUND

Little is known about how older people interpret disease and how those interpretations might relate to use of medical services.

OBJECTIVE

To assess opinions of older subjects about the cause and treatment of common diseases and how they are related to health behaviors.

DESIGN

In-home interview of a population-based sample (n = 601) of noninstitutionalized black, Hispanic, and non-Hispanic white American men and women aged 75 and older in Galveston County, Texas.

RESULTS

Substantial proportions of the subjects considered heart disease, arthritis, or difficulty sleeping to be a normal part of aging. In multivariate analyses including age, gender, education, marital status, living arrangement, global self-rating of health, and comorbidity, older black subjects were less likely to view heart disease (OR = 0.41; 95% CI, 0.26-0.64), arthritis (OR = 0.48; 95% CI, 0.31-0.73), or sleep problems (OR = 0.50; 95% CI, 0.32-0.77) as a normal part of aging than were non-Hispanic whites. Blacks were more than three times as likely to attribute heart disease to overwork or stress than were non-Hispanic whites. In multivariate analyses, subjects who considered all three of the medical conditions to be a normal part of aging ("fatalistic") were less likely to have received preventive medical services in the previous year (OR = 0.13; 95% CI, 0.02-0.96), and subjects who felt that nothing could be done to treat any of the conditions ("nihilistic") were less likely to have a regular physician (OR = 0.24; 95% CI, 0.08-0.74).

CONCLUSIONS

Substantial numbers of older subjects are fatalistic about the cause of disease and/or nihilistic about its treatment. These attitudes are associated with decreased utilization of health services. Attempts to improve the health of underserved groups should employ interventions that are sensitive to the health beliefs of the targeted group.

Changes in blood pressure and risk factors for cardiovascular disease among older Mexican-Americans from 1982-1984 to 1993-1994

OBJECTIVE

To determine the 10-year changes in blood pressure and cardiovascular risk factors among older Mexican-Americans.

DESIGN

Comparative analyses of the Hispanic Health and Nutrition Examination Survey (HHANES) and the Hispanic EPESE (Established Populations for Epidemiologic Studies of the Elderly). Both of these were population-based studies using a multistage stratified probability sampling design of noninstitutionalized persons.

SETTING

Five US states in the southwest: Arizona, California, Colorado, New Mexico, and Texas.

PARTICIPANTS

A total of 216 Mexican-Americans aged 65 to 74 from the 1982-1984 HHANES and 3050 Mexican-Americans aged 65+ from the 1993-1994 Hispanic EPESE.

MEASUREMENTS

Mean systolic and diastolic blood pressure; cigarette smoking; high levels of alcohol use; body mass index and obesity; self-reported heart attack, stroke, and diabetes; hypertension.

RESULTS

Among 65- to 74-year-old Mexican-Americans, there was a decrease over time in the percent of those who smoked cigarettes from 27.60% to 13.96% and a decrease in mean systolic blood pressure level. The percent of subjects categorized as obese or severely obese increased significantly, as did the prevalence of diagnosed diabetes, increasing from 20.06% in 1982-1984 to 29.82% in 1993-1994. Mean diastolic blood pressure increased from 77.15 mm Hg in 1982-1984 to 81.21 mm Hg in 1993-1994.

CONCLUSIONS

Our findings suggest major changes in cardiovascular risk factors between 1982-1984 and 1993-1994 among older Mexican-Americans.

Information on radiation treatment in patients with breast cancer: the advantages of the linked medicare and SEER data. Surveillance, Epidemiology and End Results

Several studies have found underutilization of radiotherapy in patients with breast cancer; but there are concerns about the completeness of various databases on radiotherapy. We used the linked Medicare-SEER (Surveillance, Epidemiology and End Results) database to compare information on receipt of radiotherapy after diagnosis of breast cancer. More than 18% of women identified by Medicare data as receiving radiotherapy were not so identified by SEER, and 7% of those identified as receiving radiotherapy by SEER were not identified by Medicare. Risk of discordance on radiotherapy information between the two data sets was especially high in women receiving breast-conserving surgery. The combined SEER-Medicare database gives a more complete picture on the use of radiotherapy. The previously reported geographic variations in the use of radiotherapy for breast cancer may be due in part to underreporting of radiotherapy in some areas.

Disability in older adults. 2: Physical activity as prevention

In this 2nd article in the series on older adults (persons aged > or = 65 years), the role of physical activity in preventing disability associated with aging in the absence of specific illnesses is discussed, and different types of activities and the measures of outcome are described. Evidence for physical activity as a prevention measure is restricted to primary and secondary prevention because the application of physical activity for tertiary prevention of disability is limited. Chronic disease is considered in the context of its influence on disability only when physical activity offers some potential benefit to elderly persons.

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 declining use of axillary dissection in patients with early stage breast cancer

OBJECTIVES

To determine any changes in usage of axillary dissection over time from 1983 to 1993, and to characterize those patients who do not receive axillary node dissection.

METHODS

A total of 129,946 female patients receiving cancer-directed surgery for early stage breast cancer, who were identified from the SEER (Surveillance, Epidemiology and End Results) program and diagnosed from 1983 to 1993, were included in the study. The surgical treatment and axillary dissection were based on treatment data collected by the SEER during the first course of therapy. Logistic regression analyses were used to assess the effect of patient and tumor characteristics on the likelihood of not receiving different types of treatment.

RESULTS

The percentage of women not receiving axillary dissection has increased over time, from 14.4% in 1983 to 16.8% in 1993. Nearly a quarter of women undergoing breast conserving surgery for local stage breast cancer receive neither axillary dissection nor radiotherapy. Older, unmarried, and non-white women and those with very small (< 0.5 cm) or very large (> or = 4 cm) tumors were most likely to receive neither axillary node dissection nor irradiation. Among those not receiving axillary dissection, 42% had tumors 1-3 cm in size and were not receiving radiation therapy.

CONCLUSIONS

There is an apparent divergence between the type of patient who has been recommended as an appropriate candidate for avoiding axillary dissection (those with small tumors and those who will receive adjuvant therapy) and those who are actually not receiving axillary dissection in the community.

Lower body functioning as a predictor of subsequent disability among older Mexican Americans

BACKGROUND

Disability measures among elderly non-Hispanic White populations have traditionally been associated with activities of daily living (ADLs) and instrumental activities of daily living (IADLs). More recently, performance-based measures have increasingly been used to predict the onset of disability in initially nondisabled elderly populations.

METHODS

We used data from two waves (1993-94 and 1995-96) of the Hispanic Established Populations for the Epidemiologic Studies of the Elderly (EPESE) to assess the degree with which lower mobility performance measures predict future disability in a representative sample of older Mexican Americans from the Southwestern United States.

RESULTS

Performances on an 8-foot walk, repeated chair stands, and standing balance among nondisabled subjects at baseline were significantly associated with the onset of ADL and lower body disability 2 years later, controlling for age, gender, and the presence of medical conditions. The results were significant for each performance measure and for a measure combining all three.

CONCLUSION

This study offers further evidence that performance-based measures of lower body function are able to predict future disability in older Mexican Americans, as has been found with other elderly populations. These measures were able to detect changes over a relatively short period of time (2 years). In addition, the study found that the short (8-foot) walk was the most sensitive measure in predicting future disability.

Impact of selected medical conditions on self-reported lower-extremity function in Mexican-American elderly

OBJECTIVE

To examine the independent impact of common medical conditions on lower-extremity function in Mexican-American elderly.

DESIGN

Cross-sectional study using a probability sample of non-institutionalized Mexican Americans aged 65 or older.

SETTING

The five Southwestern states, Texas, New Mexico, Arizona, Colorado and California.

PARTICIPANTS

All subjects were interviewed in person (n = 2,873) or by proxy (n = 177) in their homes during late 1993 and early 1994.

MAIN OUTCOME MEASURES

Respondents were asked whether they could perform four activities related to lower-extremity function without help: walking across a small room, getting from a bed to a chair, walking up and down stairs, and walking half a mile. A summary measure of lower body disability created from these four items was regressed on seven common medical conditions plus five control variables using multiple logistic regression.

RESULTS

Adjusted Odds Ratios (OR) suggested that impaired lower-extremity function was associated with previous diagnosis of hip fracture (OR = 4.28), stroke (OR = 3.47), lower extremity arthritis (OR = 2.60), heart attack (OR = 2.29), diabetes (OR = 2.03) and obesity (OR = 1.50). Impaired lower-extremity function was significantly associated with older age (75+ years old), gender (female) and marital status (unmarried). In addition, there was a linear increase in the risk of function loss by number of medical conditions.

CONCLUSIONS

It appears that Mexican-American elderly diagnosed with medical conditions, especially stroke and hip fracture, have a high risk for lower-extremity dysfunction. These findings have implications for efforts to prevent or reduce lower-extremity dysfunction, as well as for the provision of community-based long-term care services for Mexican-American elderly.

The association between chronic diseases and depressive symptomatology in older Mexican Americans

BACKGROUND

Among the elderly population, the risk for psychological distress increases with the number of chronic diseases and accompanying functional disability. The prevalence of chronic medical conditions and functional disability varies substantially across ethnocultural groups, however. Using data from the Hispanic EPESE, we previously reported that among older Mexican Americans, the total number of chronic medical conditions and the presence of functional impairment are strong predictors of depressive symptoms.

METHODS

Using multiple regression, we examined the association between specific chronic diseases, individual functional disabilities, and depressive symptoms in this group of ethnic elders.

RESULTS

Multiple regression models indicated that diabetes (OR = 1.25, 95% CI = 1.03-1.56), arthritis (OR = 1.42, 95% CI = 1.17-1.72), urinary incontinence (OR = 1.94, 95% CI = 1.46-2.59), bowel incontinence (OR = 2.28, 95% CI = 1.15-4.55), kidney disease (OR = 3.11, 95% CI = 1.13-8.58), and ulcers (OR = 2.56, 95% CI = 1.23-5.29) were predictive of high levels of depressive symptoms. Hip fracture, although recognized as having a substantial impact on functional status, was not found to be associated with depressive symptoms. History of stroke was not significantly associated with depressive symptoms in bivariate or multivariate analyses, but history of stroke with residual speech problems was predictive (OR = 2.16, 95% CI = 1.01-4.79). Among specific activities of daily living, only impaired ability to walk across a room (OR = 1.65, 95% CI = 1.04-2.73) or to bathe oneself (OR = 1.87, 95% CI = 1.12-3.12) proved to be predictive in multivariate analyses.

CONCLUSIONS

This constellation of chronic medical conditions and functional disabilities is very different from those reported to be associated with depressive symptoms in older non-Hispanic White and African Americans, and appears to comprise those conditions most associated with substantial physical impairment, pain, and discomfort.

Measuring frailty in the hospitalized elderly: concept of functional homeostasis

Functional homeostasis is the ability of an individual to withstand illness without loss of function. We investigate whether the level of functional homeostasis predicts adverse outcomes in the 6 months posthospital discharge in older men and women. A prospective cohort study was conducted in an acute care geriatric inpatient unit of a university hospital. Subjects included a consecutive series of patients admitted to the unit. The Functional Independence Measure (FIM) instrument was used to assess patients at four time points: preillness, hospital admission, hospital discharge, and 6 months postdischarge. Of the 122 subjects available for analysis, 64 (52%) experienced a decline in functional level from preillness to hospital discharge and were defined as having poor functional homeostasis, whereas 58 (48%) experienced no change or an increase in functional status and were defined as having good functional homeostasis. Those with poor functional homeostasis had a higher 6-month readmission rate to the hospital (59.4 v 39.7%; P=0.03) and a higher rate of any adverse outcome (78.1 v 50%; P=0.001) than those with good functional homeostasis. In logistic regressive analyses, functional homeostasis remained a significant and powerful predictor of adverse outcomes independent of actual level of function at discharge, age, gender, living status, and other factors that might influence outcomes. Change in functional status associated with an acute illness is an independent predictor of adverse outcomes and, in this study, a better predictor than actual level of function at discharge. Functional homeostasis is one approach to the quantification of the important but elusive concept of frailty in the elderly.

Undertreatment of hypertension in older Mexican Americans

OBJECTIVE

To identify the prevalence of hypertension and factors associated with nontreatment and poor control of hypertension in Mexican Americans aged 65 years and older.

DESIGN

A population-based survey of older Mexican Americans conducted in 1993-1994.

SETTING

Subjects residing in five Southwestern states: Texas, New Mexico, Colorado, Arizona, and California.

PARTICIPANTS

An area probability sample of 3050 noninstitutionalized Mexican American men and women aged 65 and older took part in a 90-minute in-home interview, which included review of all medications taken and two sitting blood pressure measurements.

OUTCOME MEASURES

Measured were previous diagnoses of hypertension, current medication for hypertension, and current blood pressure

RESULTS

Sixty-one percent of older Mexican-Americans were hypertensive, and 51% of those with hypertension were taking antihypertensive medications. Only 25% of hypertensive subjects (18% of males and 30% of females) were in good blood pressure control (i.e., systolic blood pressure < 140 mm Hg and diastolic blood pressure < 90 mm Hg). In multivariate analyses, factors associated with increased likelihood of treatment included female gender (OR = 1.9), history of heart disease (OR = 2.4), possessing a regular source of health care (OR = 2.7), and having seen a physician two or more times in the previous year (OR = 3.8). These were also independent predictors of good blood pressure control.

CONCLUSION

Nontreatment of hypertension is still a major public health concern in older Mexican Americans. We estimate that adequate blood pressure control in this population would prevent approximately 30,000 adverse cardiovascular events over 10 years, affecting approximately 6% of the entire Mexican American older population.

Lower-extremity functioning in older Mexican Americans and its association with medical problems

OBJECTIVE

To describe lower-extremity functioning in community-dwelling older Mexican Americans and to examine its relationship with medical problems.

DESIGN

Cross-sectional analyses of survey and performance-based data obtained in a population-based study employing area probability sampling.

SETTING

Households within selected census tracts of five Southwestern states: Arizona, California, Colorado, New Mexico, and Texas.

PARTICIPANTS

A total of 2873 Mexican Americans aged 65 years and older.

MEASUREMENTS

A multidimensional questionnaire assessing demographic, sociocultural, and health variables. Standardized tests of lower-extremity physical functioning included measures of standing balance, repeated chair stands, walking, and an overall summary measure.

RESULTS

Regression analyses revealed that being more than age 75 and female, having arthritis diabetes, visual impairments, or being obese or underweight were all significantly associated with performance on both individual and summary tests of lower-extremity functioning. In separate regression analyses, the total number of medical conditions was also associated with performance.

CONCLUSIONS

The likelihood of predicting performance or inability to complete tests of lower-extremity functioning was greatest for those aged 80 and older, those with arthritis or diabetes, and those with three or more medical conditions. Because of the high prevalence of diabetes in Mexican Americans, documentation of the association of diabetes with performance-based tests of lower-extremity functioning may help guide early interventions targeted to prevent progression to more severe limitations or disability.

Effect of Nancy Reagan's mastectomy on choice of surgery for breast cancer by US women

CONTEXT

While the actions of popular figures are believed to influence the behavior of the general public, including health care decisions, little research has examined such an effect.

OBJECTIVE

To determine whether a temporal association exists between use of breast-conserving surgery (BCS) for treatment of breast cancer and Nancy Reagan's mastectomy in October 1987.

DESIGN/SETTING

Population-based observational cohort study.

PATIENTS

Two sources of data: (1) 82 230 women aged 30 years and older who were included in the Surveillance, Epidemiology, and End Results tumor registry because of a diagnosis of local or regional breast cancer from 1983 to 1990; and (2) 80057 female Medicare beneficiaries aged 65 to 79 years who received inpatient surgery for local or regional breast cancer in 1987 or 1988.

MAIN OUTCOME MEASURE

Percentage of use of BCS vs mastectomy over time.

RESULTS

Compared with women undergoing surgery for breast cancer in the third quarter of 1987 (just prior to Mrs Reagan's mastectomy), women were 25% less likely to undergo BCS in the fourth quarter of 1987 (odds ratio [OR], 0.75; 95% confidence interval [CI], 0.66-0.85) and in the first quarter of 1988 (OR, 0.76; 95% CI, 0.67-0.86). In subsequent quarters, the rate returned to the baseline. In multivariate analyses, the decline was significant among white but not nonwhite women. It was most prominent among women aged 50 to 79 years in the central and southern regions of the country, and most sustained among women living in areas with lower levels of income and education.

CONCLUSIONS

Celebrity role models can influence decisions about medical care. The influence appears strongest among persons who demographically resemble the celebrity, and those of lower income and educational status.

Complications of acute myocardial infarction in patients > or = 90 years of age

Forty consecutive 90-year-old persons with an acute myocardial infarction were studied to describe the noncardiac complications of their care. Common negative consequences of hospitalization of these patients included delirium, pressure ulcers, and poor ambulatory status at discharge.

Geographic variations in breast cancer mortality: do higher rates imply elevated incidence or poorer survival?

OBJECTIVES

Mortality rates from breast cancer are approximately 25% higher for women in the northeastern United States than for women in the South or West. This study examined the hypothesis that the elevation is due to decreased survival rather than increased incidence.

METHODS

Data on breast cancer incidence, treatment, and mortality were reviewed.

RESULTS

The elevated mortality in the Northeast is apparent only in older women. For women aged 65 years and older, breast cancer mortality is 26% higher in New England than in the South, while incidence is only 3% higher. Breast cancer mortality for older women by state correlates poorly with incidence (r = 0.28).

CONCLUSIONS

Those seeking to explain the excess breast cancer mortality in the Northeast should assess survival and should examine differences in cancer control practices that affect survival.

Immunodeficiency of aging

Aging is associated with declines in multiple areas of immune function, but to date no single mechanism has emerged as being responsible for all the observed changes. Many changes occur at different rates within individuals as well as between individuals. With advancing age there is a concomitant increase in the incidence of many infections and cancers. It is being increasingly acknowledged that autoimmune processes play a proinflammatory role in the development of many pathological conditions, such as atherosclerosis. However, direct causal relationships between specific changes in immunity and the occurrence of specific diseases are rare. There is accumulating epidemiological, in vivo and in vitro evidence to support many such direct relationships in both animals and humans. It is likely that the mechanisms underlying age-related changes in immunity are multifactorial, with both genetic and environmental factors playing a significant role. Despite the current lack of unifying theories, much active and exciting work is proceeding in the area of immune stimulation. Studies describing age-related changes in immunity, as well as the testing of interventions to reverse these changes, will continue to fill the gaps in our knowledge, leading to a more comprehensive understanding of immunosenescence.

Factors influencing unawareness of hypertension among older Mexican Americans

BACKGROUND

The objective of the study was to identify factors associated with unawareness of hypertension among Mexican Americans age 65 years and older.

METHODS

This was a population-based survey of 3,050 older Mexican Americans conducted in five Southwestern states in 1993-1994. An in-home interview included sociodemographics, review of medications, and blood pressure measurements.

RESULTS

Sixty percent of all subjects were hypertensive, and 37% of these were unaware of their diagnosis. Unaware hypertensive had significantly higher mean blood pressures than did aware hypertensives (145.7/ 86.2 mm Hg vs 142.4/83.1 mm Hg). While 77% of aware hypertensives were treated, only 10% of unaware hypertensives were treated. In multivariate analyses, factors associated with unawareness included male gender (OR = 1.8), being married (OR = 1.6), having Medicaid (OR = 1.6), having made fewer than two visits to a doctor in the past year (OR = 2.8), having a history of heart disease (OR = 0.57) or stroke (OR = 0.37), and having poor self-reported health (OR = 0.43).

CONCLUSION

Despite 3 decades of hypertension detection and education programs, unawareness of hypertension remains high among older Mexican Americans. There is a continued need for community-based education programs for hypertensives who are unaware of their diagnosis, and also there is need for programs to increase access to primary care physicians.

The effect of legislative requirements on the use of breast-conserving surgery

BACKGROUND

We studied the effect of state legislation requiring the disclosure of options for the treatment of breast cancer on the use of breast-conserving surgery in clinical practice.

METHODS

The National Cancer Institute's Surveillance, Epidemiology, and End Results registry provided data on women from 30 through 79 years of age who underwent breast-conserving surgery or mastectomy for local or regional breast cancer from 1983 through 1990. We examined the trend over time in use of breast-conserving surgery among patients in four sites (Connecticut, Iowa, Seattle, and Utah) where there were no state laws specifically requiring the disclosure of options for the treatment of breast cancer by physicians. For four additional sites (Detroit, Atlanta, New Mexico, and Hawaii) that had such legislation, we determined whether the rate of breast-conserving surgery after the legislation was different from the expected rate.

RESULTS

An attorney rated the legislation as giving most direction to physicians in Michigan, followed by Hawaii, Georgia, and New Mexico. The rate of breast-conserving surgery was up to 8.7 percent higher than expected in Detroit for six months after the passage of the Michigan law (P<0.01). The rate was up to 13.2 percent higher than expected in Hawaii for 12 months after that state's law was passed (P<0.05) and up to 6.0 percent higher than expected in Atlanta for 3 months after the passage of the Georgia law (P<0.01). After these transient increases, the surgery rates reverted to the expected levels. No significant effect was detected in New Mexico, where only a resolution without legal force was passed.

CONCLUSION

Legislation requiring physicians to disclose options for the treatment of breast cancer appeared to have only a slight and transient effect on the rate of use of breast-conserving surgery.

The effect of medical conditions on the functional limitations of Mexican-American elderly

We examined the relationship of self-reported functional status to common medical conditions using a probability sample of 3050 noninstitutionalized Mexican-American men and women aged 65 or older and residing in the Southwestern United States (Arizona, California, Colorado, New Mexico, and Texas). All subjects were interviewed in person (n = 2,873) or by proxy (n = 177) in their homes during late 1993 and early 1994. The questionnaire obtained information on self-reported functional status and prevalence of arthritis, cancer, diabetes, stroke, heart attack, and hip fracture. The prevalence of medical conditions ranged from 4.1% for hip fracture to 40.8% for arthritis. Prevalence of impairments in seven activities of daily living ranged from 5.4% for eating to 11.7% for bathing, while 25.1% could not walk up and down stairs, and 28.9% could not walk a half mile without help. In multiple logistic regression analyses, previous diagnoses of stroke and hip fracture were most predictive of functional limitations, though all conditions examined (arthritis, cancer, diabetes, stroke, heart attack, and hip fracture) were independently associated with increased odds of impairment in some activities of daily living. In general, the odds for functional impairment associated with specific medical conditions were higher than those previously published for non-Hispanic white populations. The fact that Mexican-American elderly who live in the community and who have medical conditions, especially stroke and hip fracture, are at high risk for functional impairment probably reflects the low rate of institutionalization in this population and has implications for the provision of community-based long-term care services for Mexican-American elderly.

Determinants of survival in older cancer patients

BACKGROUND

We and others have previously described a number of characteristics that are associated with delays in diagnosis and increased risk for inadequate treatment of older women and men with cancer. These characteristics include poor social support, limited access to transportation, and impaired cognition. However, there is little information on how these factors influence survival of older cancer patients.

PURPOSE

The purpose of the study was to determine which patient characteristics predicted survival up to 10 years after the diagnosis of cancer.

METHODS

In 1984, we initiated a population-based study of men and women who were 65 years of age or older, living in a six-county area of New Mexico, and newly diagnosed with cancer. For 646 individuals with cancer of the breast (n = 188), prostate (n = 247), or colon or rectum (n = 211), we assessed patient baseline characteristics, disease stage at diagnosis, and adequacy of treatment (definitive or nondefinitive) as determinants of survival for up to 10 years following diagnosis. Multivariate survival models were used to analyze the data; all P values were two-sided.

RESULTS

In multivariate analyses, we first included all patient characteristics, except the stage at diagnosis and the adequacy of treatment. In this initial analysis, the following were among variables that were significantly associated with patient survival: age, education, cancer knowledge, ethnic group, and cognitive status. When stage at diagnosis and adequacy of treatment were added to the model, both advanced stage at diagnosis (hazard ratio = 1.7 [95% confidence interval ¿CI¿ = 1.3-2.1] for diagnosis at regional stage versus local stage; hazard ratio = 3.0 [95% CI = 2.0-4.7] for distant stage versus local stage) and inadequate treatment (hazard ratio = 1.6 [95% CI = 1.1-2.3]) were associated with poor survival. However, adding stage at diagnosis and adequacy of treatment to the analysis had little influence on the magnitude of the effect of patient characteristics on survival. In separate analyses of patient data by cancer site, receipt of nondefinitive therapy was associated with increased mortality among patients with colon/rectal cancer (hazard ratio = 7.8 [95% CI = 2.8-21.4]) and breast cancer (hazard ratio = 2.2 [95% CI = 1.1-4.3]) but not among patients with prostate cancer (hazard ratio = 1.0 [95% CI = 0.6-1.9]).

CONCLUSIONS

Advanced stage at diagnosis and inadequate treatment of older cancer patients are associated with poor survival. Impaired cognition and inadequate education in elderly patients are also associated with poor survival. This decreased survival does not appear to be a consequence of known barriers to health care that are responsible for delays in diagnosis and for inadequate treatment.

IMPLICATIONS

Efforts to facilitate early diagnosis and receipt of definitive treatment for cancer in older individuals may improve their survival.