Biomedical subjects

C Derby

Publications and source records attributed to C Derby.

9 recordsLinked to original sources

PubMed2006

Incidence of epilepsy in a racially diverse, community-dwelling, elderly cohort: results from the Einstein aging study.

OBJECTIVE: To determine age-specific incidence and cumulative incidence of epilepsy in a well-defined cohort of elderly people, and to examine how rates of epilepsy are modified by sex, race, stroke, dementia, head injury, and depression. METHODS: The authors examined data from a reconstructed cohort based on 1919 community-dwelling volunteers, followed as part of a large ongoing prospective aging study. RESULTS: Age-specific incidence was 10.6 (per 100,000 person-years) between ages 45 and 59, 25.8 between ages 60 and 74, and 101.1 between ages 75 and 89. Cumulative incidence was 0.15% from age 45 to age 60, 0.38% to age 70, 1.01% to age 80, and 1.47% to age 90. In addition, the difference in cumulative incidence among African-American subjects approached statistical significance (57.6/100,000 person-years versus 26.1 in Caucasian, p=0.10), and the difference in incidence among subjects reporting a history of stroke was significantly elevated (p=0.029). Incidence of epilepsy was not statistically elevated among males, those with dementia, or individuals reporting a history of head injury or treatment for depression. Among "healthy" subjects without history of stroke, head injury, or dementia, we observed a cumulative risk of epilepsy with onset after age 60 of only 1.1%. CONCLUSIONS: The incidence of epilepsy was low in this relatively healthy cohort of elderly people, especially among subjects without known risk factors. In this study we identified African-American race as a risk factor in the elderly for epilepsy independent of stroke.

Black or African American↗

PubMed2006

Leisure activities and the risk of amnestic mild cognitive impairment in the elderly.

OBJECTIVE: To study the influence of leisure activity participation on risk of development of amnestic mild cognitive impairment (aMCI). METHODS: The authors examined the relationship between baseline level of participation in leisure activities and risk of aMCI in a prospective cohort of 437 community-residing subjects older than 75 years, initially free of dementia or aMCI, using Cox analysis adjusted for age, sex, education, and chronic illnesses. The authors derived Cognitive and Physical Activity Scales based on frequency of participation in individual activities. RESULTS: Over a median follow-up of 5.6 years, 58 subjects had development of aMCI. A one-point increase on the Cognitive (hazard ratio [HR] 0.95, 95% CI 0.91 to 0.99) but not Physical Activities Scale (HR 0.97, 95% CI 0.93 to 1.01) was associated with lower risk of aMCI. Subjects with Cognitive Activity scores in the highest (HR 0.46, 95% CI 0.24 to 0.91) and middle thirds (HR 0.52, 95% CI 0.29 to 0.96) had a lower risk of aMCI compared with subjects in the lowest third. The association persisted even after excluding subjects who converted to dementia within 2 years of meeting criteria for aMCI. CONCLUSIONS: Cognitive activity participation is associated with lower risk of development of amnestic mild cognitive impairment, even after excluding individuals at early stages of dementia.

Aged↗

PubMed2005

Dementia incidence may increase more slowly after age 90: results from the Bronx Aging Study.

BACKGROUND: Dementia incidence increases dramatically from age 65 to age 85, with many studies reporting a doubling every 5 years. The incidence beyond age 85 is not established. OBJECTIVE: To estimate the incidence of dementia as a function of age, with a particular focus on persons aged 85 and over. METHODS: The Bronx Aging Study began in 1980 with 488 healthy, nondemented community-dwelling individuals, age 75 to 85. Persons in the study received clinical examinations and cognitive testing approximately every 12 months until death or loss to follow-up. The diagnosis of dementia was made using Diagnostic and Statistical Manual of Mental Disorders-III-R at diagnostic case conferences. Dementia incidence rates were calculated for 5-year age bands using person-time of follow-up as the denominator. RESULTS: The relative incidence rate ratios of dementia for age 80 to 84 vs 75 to 79 was 2.32 (95% CI 1.23 to 4.37), the relative rate for age 85 to 89 vs 80 to 84 was 1.89 (95% CI 1.26 to 2.83), the relative rate for age 90 to 94 vs 85 to 89 was 1.49 (95% CI 0.86 to 2.58), while the relative rate for age 95 to 99 vs 90 to 94 was 1.31 (95% CI 0.38 to 4.46). Similar results were seen for men and women considered separately. Had the rate of increase from age 75 to 89 continued into the 90s, the study would have had 73% power to detect a significant difference between the rates for age 90 to 94 and 85 to 89 given the amount of observed follow-up time. CONCLUSIONS: Whereas dementia incidence continues to increase beyond age 85, the rate of increase appears to slow relative to that of 65- to 85-year-olds. These results suggest that dementia in the oldest old might be related not to the aging process itself but with age-associated risk factors.

Age Distribution↗

PubMed1996

Balance and strength training in older adults: intervention gains and Tai Chi maintenance.

OBJECTIVE: To determine the effect on balance and strength of 3 months of intensive balance and/or weight training followed by 6 months of low intensity Tai Chi training for maintenance of gains. DESIGN: Randomized control intervention. Four groups in 2 x 2 design: Control, Balance, Strength, Balance + Strength, using blinded testers. SETTING: Exercise and balance laboratory at University of Connecticut Health Center. PARTICIPANTS: Subjects were 110 healthy community dwellers (mean age 80) who were free of dementia, neurological disease, and serious cardiovascular or musculoskeletal conditions. INTERVENTIONS: Short-term training (3 months) occurred 3 times/week (45 minutes Balance and Strength, 90 minutes Balance + Strength). Balance training included equilibrium control exercises of firm and foam surfaces and center-of-pressure biofeedback. Strengthening consisted of lower extremity weight-lifting. All subjects than received long-term group Tai Chi instruction (6 months, 1 hour, 1 time/week). MEASUREMENTS: Losses of balance during Sensory Organization Testing (LOB), single stance time (SST), voluntary limits of stability (FBOS), summed isokinetic torque of eight lower extremity movements (ISOK), and usual gait velocity (GVU). RESULTS AND CONCLUSIONS: Balance training meaningfully improved all balance measures by restoring performance to a level analogous to an individual 3 to 10 years younger: LOB = -2.0 +/- 0.3 (adjusted paired differences, P < .005 ANOVA); SST = 7.0 +/- 1.2 sec; and FBOS = 9.0 +/- 2.0% of foot length (P < .05). Strengthening increased ISOK by 1.1 +/- 0.1 Nm kg-1 (P < .005). There was no interaction between balance and strength training. Significant gains persisted after 6 months of Tai Chi, although there was some decrement.

Aged↗

PubMed1993

Altered sensory function and balance in older persons.

The effects of three different visual inputs (eyes open, eyes closed, and inaccurate) while standing on an unstable surface (respectively, UEO, UEC, UI) were compared in a group of healthy elderly community dwellers (N = 239; mean age 76) and young (N = 34; mean age 34) adults. Subjects with medical factors known to affect balance were excluded. Body sway and loss of balance measured dynamic force platform (EquiTest, NeuroCom International). Visual and somatosensory inputs were rendered inaccurate through tilting of the standing surface and/or the visual surround proportional to the subject's angle of sway (sway-referencing). The elderly group had significantly more difficulty balancing during UEC and UI, and a larger proportion lost their balance during UI. These findings are compared to those of other dynamic posturography studies in which sensory inputs were controlled. Issues of age, frailty, screening, and test protocol are addressed in order to account for differences in results among studies.

Aged↗

PubMed1993

Training balance and strength in the elderly to improve function.

Short-term exposure to altered sensory input or destabilizing platform movement results in significant improvement in sway control and inhibition of inappropriate motor responses, resulting in improved balance during repetitive testing. In addition, there is recent evidence that strength and function can be increased in both active and frail elderly who participate in strength training programs. Therefore, the hypotheses to be tested are that (1) balance training alone, or (2) strength training alone will each be capable of significantly improving balance, gait, and functional mobility, and that (3) a combined program of balance and strength training will be more effective than either approach alone. These hypotheses will be tested relative to a control group, using a 2 x 2 design (30 subjects per group), in a community-dwelling elderly at least 75 years of age. Intervention sessions of at least 45 minutes will occur three times per week for 3 months, with 6 months of follow-up, home-based Tai Chi training. The primary outcome variable is a basic measure of functional balance, ie, the occurrence of loss of balance during tilts of the support and/or movement of the visual surround.

Aged↗

PubMed1991

DNA polymorphism haplotypes of the human lipoprotein lipase gene: possible association with high density lipoprotein levels.

Lipoprotein lipase (LPL) plays a central role in the metabolism of lipoproteins by hydrolyzing the core triglycerides of circulating very low density lipoproteins and chylomicrons. The enzyme is encoded by a gene about 30 kb in size located on the short arm of human chromosome 8. We have determined the locations of the four common DNA polymorphisms along the gene, including a polymorphism that occurred only among an American black population examined. These restriction site polymorphisms were used for haplotype analysis of Mediterranean and US black families. Estimation of the extent of nonrandom association between these polymorphisms indicated considerable linkage disequilibrium between these sites. No correlation was observed between the level of linkage disequilibrium and the physical distance of the polymorphic sites. The polymorphism information content of the haplotypes ranged from 0.65 to 0.74, thereby constituting a relatively useful genetic marker on chromosome 8. We tested for possible associations between the polymorphisms and circulating lipoprotein phenotypes in a population of 139 Caucasians undergoing coronary arteriography and 50 of their spouses. Some possibly significant associations between LPL gene polymorphisms and levels of high density lipoprotein cholesterol (P = 0.015) and total plasma cholesterol (P = 0.025) were observed. In contrast to a previous report, we found no significant associations with the levels of plasma triglycerides.

Adult↗

PubMed1988

Enzymatic analysis of total- and HDL-cholesterol: comparison with the standardized Liebermann-Burchard method used by the Lipid Research Clinics program.

We compared two enzymatic cholesterol methods with the standardized chemical method used in the Lipid Research Clinic's (LRC) program. The methods were used to measure total cholesterol and high density lipoprotein (HDL) cholesterol in heparin-MnCl2 supernatants of 1,812 sera collected over a 16-mth period from subjects who were sampled as part of the Hispanic Health and Nutrition Examination Survey. Thirty percent of the subjects had fasted for 12 h or more before venepuncture. The enzymatic total cholesterol values were 1.4-1.8% lower than the LRC method and both enzymatic methods correlated highly with the LRC method (r greater than 0.97). The enzymatic HDL cholesterol values were 2.4 and 6.4% higher than the LRC method, and the correlation between the enzymatic and LRC methods was greater than 0.93. The differences between the enzymatic and LRC methods were the same in samples from fasting and non-fasting subjects.

Cholesterol↗

PubMed1984

Predicting the outcome of hospitalization for elderly persons: home versus nursing home.

Fifty elderly persons who had been admitted to an acute care hospital from home and discharged to nursing homes were compared with 50 elderly persons who had been admitted to the same hospital from home and discharged to home during the same period. Discriminant function analyses were done to predict discharge status from patient characteristics at the time of admission as well as later in the hospital stay. Discharge status was predicted correctly for 88% of men and 75% of women, using patient characteristics available at the time of admission. When certain characteristics available later in the hospital stay were added, prediction improved to 98% for men and 86% for women.

Activities of Daily Living↗