Marcel E. Salive

Lower-Extremity Function in Persons over the Age of 70 Years as a Predictor of Subsequent Disability

BACKGROUND Functional assessment is an important part of the evaluation of elderly persons. We conducted this study to determine whether objective measures of physical function can predict subsequent disability in older persons. METHODS This prospective cohort study included men and women 71 years of age or older who were living in the community, who reported no disability in the activities of daily living, and who reported that they were able to walk one-half mile (0.8 km) and climb stairs without assistance. The subjects completed a short battery of physical-performance tests and participated in a follow-up interview four years later. The tests included an assessment of standing balance, a timed 8-ft (2.4-m) walk at a normal pace, and a timed test of five repetitions of rising from a chair and sitting down. RESULTS Among the 1122 subjects who were not disabled at base line and who participated in the four-year follow-up, lower scores on the base-line performance tests were associated with a statistically significant, graduated increase in the frequency of disability in the activities of daily living and mobility-related disability at follow-up. After adjustment for age, sex, and the presence of chronic disease, those with the lowest scores on the performance tests were 4.2 to 4.9 times as likely to have disability at four years as those with the highest performance scores, and those with intermediate performance scores were 1.6 to 1.8 times as likely to have disability. CONCLUSIONS Among nondisabled older persons living in the community, objective measures of lower-extremity function were highly predictive of subsequent disability. Measures of physical performance may identify older persons with a preclinical stage of disability who may benefit from interventions to prevent the development of frank disability.

Serum creatinine levels in the US population: Third National Health and Nutrition Examination Survey

This report describes the distribution of serum creatinine levels by sex, age, and ethnic group in a representative sample of the US population. Serum creatinine level was evaluated in the third National Health and Nutrition Examination Survey (NHANES III) in 18,723 participants aged 12 years and older who were examined between 1988 and 1994. Differences in mean serum creatinine levels were compared for subgroups defined by sex, age, and ethnicity (non-Hispanic white, non-Hispanic black, and Mexican-American). The mean serum creatinine value was 0.96 mg/dL for women in the United States and 1.16 mg/dL for men. Overall mean creatinine levels were highest in non-Hispanic blacks (women, 1.01 mg/dL; men, 1.25 mg/dL), lower in non-Hispanic whites (women, 0.97 mg/dL; men, 1.16 mg/dL), and lowest in Mexican-Americans (women, 0.86 mg/dL; men, 1.07 mg/dL). Mean serum creatinine levels increased with age among both men and women in all three ethnic groups, with total US mean levels ranging from 0.88 to 1.10 mg/dL in women and 1.00 to 1.29 mg/dL in men. The highest mean creatinine level was seen in non-Hispanic black men aged 60+ years. In the total US population, creatinine levels of 1.5 mg/dL or greater were seen in 9.74% of men and 1.78% of women. Overall, among the US noninstitutionalized population, 10.9 million people are estimated to have creatinine values of 1.5 mg/dL or greater, 3.0 million have values of 1.7 mg/dL or greater, and 0.8 million have serum creatinine levels of 2.0 mg/dL or greater. Mean serum creatinine values are higher in men, non-Hispanic blacks, and older persons and are lower in Mexican-Americans. In the absence of information on glomerular filtration rate (GFR) or lean body mass, it is not clear to what extent the variability by sex, ethnicity, and age reflects normal physiological differences rather than the presence of kidney disease. Until this information is known, the use of a single cutpoint to define elevated serum creatinine values may be misleading.

Calcium-channel blockade and incidence of cancer in aged populations

BACKGROUND Calcium-channel blockers can alter apoptosis, a mechanism for destruction of cancer cells. We examined whether the long-term use of calcium-channel blockers is associated with an increased risk of cancer. METHODS Between 1988 and 1992 we carried out a prospective cohort study of 5052 people aged 71 years or more and who lived in three regions of Massachusetts, Iowa, and Connecticut USA. Those taking calcium-channel blockers (n = 451) were compared with all other participants (n = 4601). The incidence of cancer was assessed by survey of hospital discharge diagnoses and causes of death. These outcomes were validated by the cancer registry in the one region where it was available. Demographic variables, disability, cigarette smoking, alcohol consumption, blood pressure, body-mass index, use of other drugs, hospital admissions for other causes, and comorbidity were all assessed as possible confounding factors. FINDINGS The hazard ratio for cancer associated with calcium-channel blockers (1549 person-years, 47 events) compared with those not taking calcium-channel blockers (17225 person-years, 373 events) was 1.72 (95% CI 1.27-2.34, p = 0.0005), after adjustment for confounding factors. A significant dose-response gradient was found. Hazard ratios associated with verapamil, diltiazem, and nifedipine did not differ significantly from each other. The results remained unchanged in community-specific analyses. The association between calcium-channel blockers and cancer was found with most of the common cancers. INTERPRETATION Calcium-channel blockers were associated with a general increased risk of cancer in the study populations, which suggested a common mechanism. These observational findings should be confirmed by other studies.

Multimorbidity in Older Adults

Multimorbidity, the coexistence of 2 or more chronic conditions, has become prevalent among older adults as mortality rates have declined and the population has aged. We examined population-based administrative claims data indicating specific health service delivery to nearly 31 million Medicare fee-for-service beneficiaries for 15 prevalent chronic conditions. A total of 67% had multimorbidity, which increased with age, from 50% for persons under age 65 years to 62% for those aged 65-74 years and 81.5% for those aged ≥85 years. A systematic review identified 16 other prevalence studies conducted in community samples that included older adults, with median prevalence of 63% and a mode of 67%. Prevalence differences between studies are probably due to methodological biases; no studies were comparable. Key methodological issues arise from elements of the case definition, including type and number of chronic conditions included, ascertainment methods, and source population. Standardized methods for measuring multimorbidity are needed to enable public health surveillance and prevention. Multimorbidity is associated with elevated risk of death, disability, poor functional status, poor quality of life, and adverse drug events. Additional research is needed to develop an understanding of causal pathways and to further develop and test potential clinical and population interventions targeting multimorbidity.

Association of visual impairment with mobility and physical function.

To examine the association of distant vision and physical function in the population of older adults.

Do calcium channel blockers increase the risk of cancer

Calcium channel blockers can block calcium signals that trigger cell differentiation and apoptosis, which are important mechanisms of cancer growth regulation. To ascertain whether calcium channel blocker use was associated with an increased risk of cancer, 750 hypertensive persons age > or = 71 years, with no history of cancer at baseline, were followed from 1988 through 1992. The patients were using either beta-blockers, angiotensin converting enzyme inhibitors or calcium channel blockers (verapamil, nifedipine, and diltiazem; mainly of the short-acting variety). Compared to beta-blockers (n = 424, 28 events), after adjusting for age, gender, race, smoking, body mass index, and number of hospital admissions not related with cancer, the relative risks of cancer (95% confidence interval) for angiotensin converting enzyme inhibitors (n = 124, 6 events) and calcium channel blockers (n = 202, 27 events) were 0.73 (0.30 to 1.78) and 2.02 (1.16 to 3.54), respectively. These findings indicate that calcium channel blocker therapy might increase the risk of cancer. New data are needed in patients using modern calcium channel blocker agents with more gradual absorption. This report should encourage further study of cancer outcomes in elderly patients who are vulnerable to cancer and who are receiving calcium channel blockers.

Anemia and Hemoglobin Levels in Older Persons: Relationship with Age, Gender, and Health Status

To determine the relationship of hemoglobin levels and anemia with age and health status in older adults.

An overview of the vaccine adverse event reporting system (VAERS) as a surveillance system

We evaluated the Vaccine Adverse Event Reporting System (VAERS), the spontaneous reporting system for vaccine-associated adverse events in the United States, as a public health surveillance system, using evaluation guidelines from the Centers for Disease Control and Prevention. We found that VAERS is simple for reporters to use, flexible by design and its data are available in a timely fashion. The predictive value positive for one severe event is known to be high, but for most events is unknown. The acceptability, sensitivity and representativeness of VAERS are unknown. The study of vaccine safety is complicated by underreporting, erroneous reporting, frequent multiple exposures and multiple outcomes.

Association of education with incidence of cognitive impairment in three established populations for epidemiologic studies of the elderly.

We analyzed the association of education, occupation, and sex with incidence of cognitive impairment using data from three communities in the Established Populations for Epidemiologic Studies of the Elderly (EPESE) projects (New Haven, East Boston, and Iowa). Participants were initially interviewed in 1981-1983, with follow-up 3 and 6 years later. Incident cognitive impairment was defined on the basis of either: (1) increase in the number of errors in Short Portable Mental Status Questionnaire (SPMSQ) (i.e. from a baseline level below the cutoff value to a score above the cutoff), or (2) inability to respond to interview questions at a follow-up contact (requiring a proxy informant), or (3) death with a recorded diagnosis of a dementing illness. In multiple logistic regression models, the major factors predicting the development of cognitive impairment were advanced age, any errors on baseline SPMSQ, 8 or fewer years of education, and occupation. Education and occupation remained significant predictors after controlling for age, site, sex, stroke, and baseline SPMSQ score.

Functional Blindness and Visual Impairment in Older Adults from Three Communities

PURPOSE The purpose of this study is to examine the association of sociodemographic factors with functional blindness and visual impairment in an aged population. METHODS Three population-based cohorts (East Boston, MA; New Haven, CT; and Iowa and Washington Counties, IA) of persons aged 71 years and older were screened for bilateral functional near and distant vision during an in-home interview in 1988. RESULTS Screening was completed by 5335 participants. The prevalence of functional blindness increased with age, from 1% at age 71 to 74 years to 17% in those 90 years of age and older. Functional visual impairment increased from 7% at age 71 to 74 years to 39% in those 90 years of age and older. In multivariate analyses, residence in a nursing home, older age, glaucoma, insulin-requiring diabetes at baseline, East Boston site, history of cataract, and lower 1982 income were independent and significantly associated with both functional blindness and visual impairment. Age and nursing home residence were significantly (P < 0.05) more strongly associated with blindness (odds ratios 4.8 and 6.1, respectively) than they were with visual impairment. CONCLUSION Functional blindness and visual impairment are quite prevalent among the oldest old and the institutionalized. The number of affected individuals will increase as the population ages and life expectancy increases. Although visual problems are associated with aging, nursing home residence, health problems, and socioeconomic conditions, they may be readily remediable and may lead to immediate improvements in quality of life.