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PubMed1985

Longitudinal changes in time estimation in affective disorders: a preliminary study.

8 patients with hospital diagnoses of major affective disorder were studied by repeated measurements of time estimation using the three different methods of metronome adjustment, verbal estimation and operative estimation (production) of short time intervals. Retrospective estimations of longer intervals were also studied. The diagnoses were evaluated according to DSM III criteria. The degree of mental disturbance was rated with subscales of the Comprehensive Psychopathological Rating Scale. Earlier findings had indicated that manic patients tend to overestimate short time intervals and that some depressed patients underestimated time, but some investigators have reported different results. A longitudinal study could possibly support the earlier findings if the time estimations should vary with the clinical states of the patients. Such a variation was suggested by the results of 5 of the 8 patients. In several cases there were statistically significant correlations between the results of time estimations and the rating scores. This partly supports earlier findings. Associations between time estimations and changes in clinical state seem to be present in some cases of major affective disorders. Operative estimations were best correlated with ratings in most cases.

Adult↗
PubMed2000

A comparison of the longitudinal changes in quantitative ultrasound with dual-energy X-ray absorptiometry: the four-year effects of hormone replacement therapy.

Quantitative ultrasound (QUS) has been proposed as a tool which can measure both the quantitative and qualitative aspects of bone tissue and can predict the future risk of osteoporotic fractures. However, the usefulness of QUS in long-term monitoring has yet to be defined. We studied a group of early postmenopausal women over a 4-year period. Thirty subjects were allocated to hormone replacement therapy and 30 selected as controls matched for age, years past the menopause (YPM) and bone mineral density (BMD) at the anteroposterior spine (AP spine). The mean age of the subjects was 52.4 years (SD 3.9 years), mean YPM 4.0 years (SD 3.2) and all subjects had a BMD T-score above -2.5 SD (number of standard units related to the young normal mean population). BMD was measured at baseline and annually by dual-energy X-ray absorptiometry (DXA) at the AP spine and total hip, and QUS carried out at the calcaneus, measuring broadband ultrasound attenuation (BUA), speed of sound (SOS) and Stiffness. Mean percentage changes from baseline were assessed at 2 and 4 years. The overall treatment effect (defined as the difference in percentage change between the two groups) was: AP spine BMD, 11.4%; total hip BMD, 7.4%; BUA, 6.4%; SOS, 1.1%; and Stiffness, 10.4% (p<0.01). To compare the long-term precision of the two techniques we calculated the Standardized Precision, which for QUS was approximately 2-3 times that of DXA, for a given rate of change. The ability of each site to monitor response to treatment was assessed by calculating the Treatment Response Index (Treatment Effect/Standardized Precision), which was: AP spine BMD, 10.4; total hip BMD, 3.9; BUA, 3.1; SOS, 0.3; and Stiffness, 4.2. This was then normalized for AP spine BMD (to compare the role of QUS against the current standard, AP Spine BMD), which was: total hip BMD, 0.38; BUA, 0.30; Stiffness, 0.40 (p<0.01); and SOS, 0.03 (NS). In summary, QUS parameters in the early menopause showed a similar rate of decline as AP spine BMD and total hip BMD measured by DXA. Hormone replacement therapy results in bone gain at the AP spine and total hip, and prevents loss in BUA and SOS measured by QUS at the calcaneus. QUS has a potential role in long-term monitoring, although presently the time period to follow individual subjects remains 2-3 times that for DXA, for a given rate of change. Anteroposterior spine remains the current optimal DXA monitoring site due to its greater rate of change and better long-term precision.

Absorptiometry, Photon↗
PubMedDate not supplied

Prostatic growth rate determined from MRI data: age-related longitudinal changes.

Men with prostatic enlargement are at highest risk of developing symptomatic lower urinary tract symptoms (LUTS) and related outcomes, such as acute urinary retention. The study of prostatic growth rate can identify the age range at which prostate growth peaks. Evaluation of the natural course of prostate growth requires repeated intraindividual volume measurements at time intervals sufficient to document growth. Our objective was to examine age-stratified prostate growth rates from men taking part in a longitudinal study of aging using magnetic resonance imaging (MRI) of the prostate. Sixty-four men (ages 30-71 years) enrolled in the Baltimore Longitudinal Study of Aging (BLSA) who had T2 pelvic MRIs taken approximately every 2 years were studied. Men were age stratified into four groups: <45, 45-55, 56-65, and >65 years old. Whole prostate and central gland (anatomically referred to as the transition zone) volumes were determined from the MRI images by a semi-automated image analysis program. Peripheral gland volumes were calculated as the difference between whole prostate and central gland volumes. Growth rates (cc per year) were calculated as change in volume divided by the time interval. On the basis of measurements from the T2 images (n = 128), we observed a linear trend between prostate volume and age. The overall prostate growth rate was 2.36 +/- 3.52 cc per year. Age-stratified growth rates revealed that prostate growth increased with age, peaked at 4.15 +/- 4.98 cc/year for the 56-65-year-old age group and then declined rapidly for the older-aged men. The central gland growth rates followed a trend similar to total prostate volume. These data suggest that there is an age-related increase in prostate growth rate that peaks in men ages 56-65 and then declines. Identification of this trend in prostate growth may aid physicians in targeting men for early diagnosis of LUTS and for possible early intervention. Future studies with a larger sample size are necessary to substantiate these findings.

Adolescent↗
PubMed2000

Longitudinal changes in growth hormone secretory process irregularity assessed transpubertally in healthy boys.

Clarifying the time evolution, and underlying neuroendocrine regulation, of hormone secretion during puberty is of pivotal importance both physiologically and clinically. We sought to determine whether clinical growth and elevated growth hormone (GH) release in pubertal boys are associated with shifts in the irregularity of GH secretory patterns. We studied GH release in 23 healthy boys longitudinally at approximately 4-mo intervals over a 6-yr period throughout puberty, by repetitive blood sampling at 20-min intervals for 24 h on each study date. To quantify serial irregularity in the GH profiles, we utilized approximate entropy (ApEn), a scale- and model-independent quantification of the extent of sequential "randomness." Complementary statistical analyses establish that on a per-subject basis, serum GH concentration-time series show greatest secretory disorderliness (maximal ApEn) in prepuberty and mid-to-late puberty, followed by a steep decline in ApEn to maximal orderliness in postpubertal adolescence (P < 0.0001, ANOVA). Pooling all subject comparisons, we observed a persistent positive correlation between ApEn and growth velocity (GrVel), Pearson r = 0.467 (P < < 10(-10)). Moreover, in general, ApEn(GH) preceded GrVel evolution, with a time frame lead of 4-8 mo providing the most pronounced correlations between ApEn and GrVel. In the setting of low postpubertal growth, per-subject ApEn values fell to approximately one-half of maximal ApEn values and, on average, were in the 13th percentile from minimal (P < < 10(-10)) for fully mature boys. Thus, in a longitudinal transpubertal analysis, greater irregularity in GH secretion corresponds to greater linear growth in boys, which culminates in highly regular GH secretory dynamics after sexual maturity. In addition to clinical utility, there may be added experimental merit in knowing that GH dynamics typically predict accelerated linear growth in 4-8 mo.

Adolescent↗
PubMed1997

Longitudinal changes in testosterone, luteinizing hormone, and follicle-stimulating hormone in healthy older men.

Cross-sectional studies have demonstrated a decline in testosterone and free and bioavailable testosterone with age. This occurs in a majority of older persons without an increase in luteinizing hormone (LH), suggesting that a component of the testosterone decrease is due to secondary hypogonadism. To determine whether these findings could be duplicated in a longitudinal study, we measured testosterone, LH, follicle-stimulating hormone (FSH), and sex hormone-binding globulin (SHBG) levels in 77 men participating in the New Mexico Aging Process Study who had sera available in 1980 or 1981 and two or more serial samples in 1982, 1984, 1989, and/or 1994. Thirty-nine subjects had samples available from both 1980 and 1994. The age at entry into the study ranged from 61 to 87 years. Testosterone levels decreased over the 15 years of the study. In persons who were alive for the duration of the study, testosterone levels were significantly lower 5 years before termination of the study (P < .05). Testosterone levels did not differ at entry into the study among those who died and those who were alive at the end of the study period. Eight of 77 subjects (10%) had LH levels above the normal range at some time during the study. In contrast, 43% of subjects had elevated FSH levels. Both LH and FSH increased significantly with age. SHBG levels were measured in 1980 and 1994 and increased significantly with age (P < .0001). LH and FSH were highly correlated with one another, but neither correlated with testosterone. This study demonstrated a longitudinal decline in testosterone and an increase in LH and FSH in older men. The average rate of decrement in testosterone concentration was 110 ng/dL every decade.

Aged↗
PubMedDate not supplied

Serial cognitive testing in temporal lobe epilepsy: longitudinal changes with medical and surgical therapies.

Cognitive testing was repeated at intervals ranging from 1 to 8 years in 47 adult patients with temporal lobe epilepsy (TLE). Each patient underwent standardized batteries, including the Wechsler Adult Intelligence Scale, Revised (WAIS-R), and Wechsler Memory Scale (WMS). Both surgically treated and nonsurgical patients were examined. The nonsurgical group underwent serial testing for clinical indications, usually for complaints of memory dysfunction. Longitudinal testing could not verify any mean deterioration of intellect or memory in this group; variance over time was similar to test-retest norms in healthy controls. WAIS-R scores before and after resection in the surgical group were similar to our serial WAIS-R data in nonsurgical patients. When we divided surgical patients according to side of epileptogenesis, we noted the expected differences in verbal and visual memory. Right-sided surgery patients improved significantly in Full-Scale IQ (FSIQ) and tended to improve in logical memory on postoperative testing. Patients undergoing left resections had no retest improvement and tended to show decrease in several measures of verbal memory. Our findings should stimulate continued investigation into the natural history of lateralized memory and intellectual function in epilepsy, particularly to clarify long-term cognitive outcome in nonsurgical patients.

Adult↗
PubMed1985

Validation of exercise-enhanced risk assessment of coronary heart disease events: longitudinal changes in incidence in Seattle community practice.

Noninvasive criteria developed in a learning series for exercise-enhanced risk assessment for events due to coronary heart disease have been applied to a test series in a later population sample. Men in the same age and risk groups for each pretest clinical classification show similar gradients of risk. Thus, exercise-enhanced criteria for risk assessment are validated. Age-standardized event rates show a reduction longitudinally in healthy men and patients who have had coronary bypass surgery.

Adult↗
PubMed2003

Longitudinal changes in the accuracy of reported energy intake in girls 10-15 y of age.

BACKGROUND: Dietary records are often used to estimate individual energy needs and population energy requirements. However, significant underreporting of total energy intake (EI) has been found when EI is compared with total energy expenditure (EE) measured by doubly labeled water. OBJECTIVE: This study aimed to determine whether the accuracy of reported EI decreases from middle childhood to adolescence. DESIGN: In this longitudinal study of 26 healthy girls, EI and EE were measured at ages 10, 12, and 15 y. Accuracy of reported EI (EI/EE x 100%) was calculated at each age. At study entry, girls had a mean (+/- SD) body mass index (in kg/m(2)) of 16.8 +/- 1.9 and percentage body fat of 24.0 +/- 4.6%. Measurements of EI were a 7-d dietary record and those of EE were by doubly labeled water. RESULTS: As they got older, girls tended to report EI less accurately: the average accuracy was 88 +/- 13% at age 10 y, 77 +/- 21% at age 12 y, and 68 +/- 17% at age 15 y. The declines in reporting accuracy from age 10 y to age 12 y and from age 10 y to age 15 y were statistically significant (P = 0.03 and P = 0.001, respectively). Reporting accuracy also declined from age 12 to age 15 y but not significantly. When percentage body fat was added to the model, results were essentially unchanged. CONCLUSION: Because of the decline in EI reporting accuracy with age, the use of EI data obtained from dietary records in adolescent girls will result in substantial underestimation of energy needs.

Adolescent↗
PubMed1994

Longitudinal changes in symptoms and plasma homovanillic acid levels in chronically medicated schizophrenic patients.

A correlation has been noted between the changes in plasma homovanillic acid concentrations and changes in psychiatric symptoms induced by neuroleptic treatment. Our objective was to determine whether plasma homovanillic acid concentration changed in accordance with the changes in symptoms over time. Twenty-eight chronically medicated schizophrenic inpatients received the same treatment regimen for 1 year. Symptoms and plasma homovanillic acid concentrations were examined every month and whenever conditions deteriorated. Plasma homovanillic acid concentrations were significantly higher in the patients in the worst condition than in the patients in the best condition. Further, when comparing the best and worst conditions of both the positive and negative symptoms, the change in psychiatric rating of positive and negative symptoms was correlated significantly with the change in plasma homovanillic acid level. These results suggest that a change in plasma homovanillic acid concentration can be produced not only by neuroleptic-induced dopaminergic blocking but also by a change in positive and negative symptoms of schizophrenia.

Adult↗
PubMed2005

The relationship of longitudinal change in reproductive hormones and vasomotor symptoms during the menopausal transition.

CONTEXT: The relationship of reproductive hormones to vasomotor symptoms (VMS) has been incompletely explored, although an increase in such symptoms at midlife and their reduction with hormone therapy suggest a strong and direct relationship. Vasomotor symptoms are reported by 65-76% of women traversing the menopausal transition and are a primary reason for medical intervention during this life stage. OBJECTIVE: The purpose of this report was to relate longitudinal serum concentrations of the reproductive hormones estradiol (E2), FSH, testosterone (T), dehydroepiandrosterone sulfate (DHEAS), and SHBG and the free hormone indices free E2 index (FEI) and free T index (FTI) with the occurrence of VMS in women traversing the menopausal transition. DESIGN AND SETTING: The Study of Women's Health Across the Nation is a multisite, longitudinal, cohort study of the menopausal transition being conducted in community-based groups of women. PARTICIPANTS AND MAIN OUTCOME MEASURES: At baseline, 3302 menstruating women who belonged to one of five ethnic/racial groups were recruited and followed up with annual visits. Frequencies of symptoms (hot flashes, night sweats) for the prior 2 wk and measures of other covariates as well as potentially confounding variables were self-reported in the annual interview. Serum was obtained annually, on d 2-5 of a spontaneous cycle in cycling women or within 90 d of the anniversary of the baseline study visit in noncycling women and assayed for FSH, E2, T, SHBG, and DHEAS. FTI and FEI were calculated. This analysis incorporated available longitudinal data from 3293 women, excluding information collected at or after first report of hormone therapy use or hysterectomy. Data were analyzed using longitudinal marginal logistic regression models and a partial proportional odds model. RESULTS: After adjusting for age, body mass index, and other related covariates, VMS prevalence increased with higher (log)FSH concentrations, and the increase was greater when blood was drawn more than 5 d after menses began. FSH concentrations were positively associated with the frequency of either hot flashes or night sweats, and higher FSH concentrations were associated with greater odds of reporting more frequent symptoms. Vasomotor symptom prevalence decreased with higher (log)E2, (sqrt)SHBG, and (log)FEI but only when these hormone values were modeled independently of (log)FSH values and the specimens were obtained outside the d 2-5 window. When modeled simultaneously with (log)FSH, (log)E2, (sqrt)SHBG, and (log)FEI were no longer significantly associated with symptom prevalence. (Cubic root)T and (sqrt)DHEAS concentrations and (log)FTI were not associated with the prevalence of VMS. CONCLUSIONS: Annual serum FSH concentrations, but not E2, T, DHEAS, FTI, or FEI when collectively modeled longitudinally, are associated with both the prevalence and frequency of VMS in women at midlife.

Adult↗
PubMed1998

Longitudinal changes in dehydroepiandrosterone concentrations in men and women.

Dehydroepiandrosterone, an adrenal steroid, has many purported roles in the body and has been used as an oral supplement in the treatment of various illnesses. Because little is known about normal changes over time in dehydroepiandrosterone concentrations, we studied the 5-year change in plasma dehydroepiandrosterone concentrations in 614 free-living adults. Two hundred seventy-three males and 341 females had dehydroepiandrosterone and dehydroepiandrosterone sulfate concentrations measured in 1989 and 1994. Demographic data were also obtained. Dehydroepiandrosterone concentrations differed significantly by sex and 5-year age group. The average decline in dehydroepiandrosterone was 5.6%/year, and the rate of decline was directly related to age but not to sex, measures of adiposity, or serum glucose. Dehydroepiandrosterone sulfate concentrations differed significantly by sex and age group. The average decline in the sulfated hormone was 2.0%/year and was not related to age, sex, measures of adiposity, or serum glucose. Knowledge of the natural course of age-related changes in dehydroepiandrosterone and dehydroepiandrosterone sulfate concentrations is essential to our understanding of the relationship of dehydroepiandrosterone to chronic diseases.

Adult↗
PubMed2002

Early detection and longitudinal changes in amyotrophic lateral sclerosis by (1)H MRSI.

OBJECTIVE: To determine 1) the reproducibility of metabolite measurements by (1)H MRS in the motor cortex; 2) the extent to which (1)H MRS imaging (MRSI) detects abnormal concentrations of N-acetylaspartate (NAA)-, choline (Cho)-, and creatine (Cre)-containing compounds in early stages of ALS; and 3) the metabolite changes over time in ALS. METHODS: Sixteen patients with definite or probable ALS, 12 with possible or suspected ALS, and 12 healthy controls underwent structural MRI and multislice (1)H MRSI. (1)H MRSI data were coregistered with tissue-segmented MRI data to obtain concentrations of NAA, Cre, and Cho in the left and right motor cortex and in gray matter and white matter of nonmotor regions in the brain. RESULTS: The interclass correlation coefficient of NAA was 0.53 in the motor cortex tissue and 0.83 in nonmotor cortex tissue. When cross-sectional data for patients were compared with those for controls, the NAA/(Cre + Cho) ratio in the motor cortex region was significantly reduced, primarily due to increases in Cre and Cho and a decrease in NAA concentrations. A similar, although not significant, trend of increased Cho and Cre and reduced NAA levels was also observed for patients with possible or suspected ALS. Furthermore, in longitudinal studies, decreases in NAA, Cre, and Cho concentrations were detected in motor cortex but not in nonmotor regions in ALS. CONCLUSION: Metabolite changes measured by (1)H MRSI may provide a surrogate marker of ALS that can aid detection of early disease and monitor progression and treatment response.

Amyotrophic Lateral Sclerosis↗
PubMed2006

Longitudinal changes of cerebral glucose metabolism in semantic dementia.

BACKGROUND: Semantic dementia (SD). OBJECTIVE: To identify the pattern of decline of cerebral glucose metabolism in SD using cerebral (18)F-fluoro-2-desoxy-D-glucose positron emission tomography scanning ((18)F-FDG-PET). METHODS: Eight patients with SD underwent (18)F-FDG-PET at baseline and at re-examination in average 15 months later. RESULTS: Compared with healthy control subjects, patients with SD showed a significant asymmetrical (left > right) hypometabolism of the temporal lobes, particularly of the anterior poles, at baseline. At follow-up, we observed a deterioration of cognitive abilities. However, in addition to the temporal lobes no other cortical or subcortical region showed a significant reduction of glucose metabolism except the anterior cingulate cortex (pcorr < 0.05). CONCLUSION: Subtle functional changes suffice to produce significant neuropsycho- logical deterioration.

Age of Onset↗
PubMed2006

Longitudinal changes in aerobic capacity: implications for concepts of aging.

BACKGROUND: Whereas aerobic capacity declines with age, major factors responsible for such decline have been poorly defined by past studies. METHODS: Participants were relatively healthy older individuals (339 women, 253 men) in whom demographic information and cardiopulmonary physiological measurements were obtained at baseline and biannually for three additional measurements. RESULTS: The study identified progressive declines in both forced expiratory volume in 1 second (FEV(1)) and in maximal exercise heart rate as two variables that accounted primarily for the longitudinal decline of aerobic performance in this cohort of relatively fit older persons who achieved high respiratory exchange ratios (RER; mean = 1.08 for women, 1.12 for men). Whereas women achieved a peak oxygen consumption (VO(2peak)) only 77% that of men, oxygen uptake became similar to men (to 95%) when measured per kilogram of lean body mass rather than per kilogram of total body mass. During the 6 years of the study (four time points) aerobic capacity declined in both sexes, however, less steeply for women than for men (18% vs 24% per decade, respectively). The rate of decline was independent of baseline variables such as body composition (e.g., lean body mass, lean/fat ratio), smoking status, medications, or concomitant health conditions, even though these variables strongly influenced baseline aerobic performance. Inclusion of FEV(1) and maximal exercise heart rate into the statistical models, however, accounted for most of the longitudinal decline of aerobic performance. When adjusted for these two variables, aerobic capacity declined 9.7% and 10.4% per decade in women and men, respectively. CONCLUSIONS: Our findings emphasize the primary importance of declining FEV(1) and declining maximal exercise heart rate in accounting for the "aging effect" on aerobic capacity. Thus, when comparing longitudinal studies, all estimates of aerobic decline should be interpreted with respect to the specific variables included in the models, which also need to include FEV(1) and maximal exercise heart rate.

Aged↗
PubMed1992

Longitudinal changes in skin-prick test reactivity over 2 years in a population of schoolchildren with respiratory symptoms.

As part of a larger epidemiological study, 114 children with respiratory symptoms, born between 1978 and 1980, were skin-prick tested to Dermatophagoides pteronyssinus (DP), mixed grass pollens (G) and cat dander (C), and to histamine and saline controls (Bencard, U.K.) using 1 mm prick-lancets (Dome/Hollister-Stier), between July and September 1987 and again in October 1989. A weal > or = 2 mm to one or more allergens was regarded as a positive result. Each child was tested by the same investigator on each occasion, using similar techniques. Three children were excluded from analysis as they had failed to respond to histamine testing on one of the two occasions. In 1987, of the 111 children analysed, 58 (52%) children were skin-test positive, and 53 (48%) skin-test negative, while in 1989 62 (56%) were positive and 49 (44%) negative. Twelve children (11%) changed status from negative to positive, while eight (7%) changed from positive to negative. For the group as a whole the percentage agreement between the results obtained 2 years apart was 82%. In comparison to previous studies a greater number of subjects in this population than expected changed atopic status. We therefore further examined the data from those who had changed status and classified as borderline those subjects with no difference in weal size of greater than 2 mm for any allergen between 1987 and 1989. Only five children then changed status from negative to positive, none from positive to negative and 15 demonstrated only borderline changes. The coefficients of repeatability for the 106 children who did not change status were 3.37 mm, 2.80 mm and 2.33 mm for D. pteronyssinus, mixed grass pollens and cat dander respectively. The good short-term repeatability of the testing method was demonstrated in a group of 29 similar children; the coefficients of repeatability were 0.38 mm for DP and G, and 0.72 mm for C. These data demonstrate that, in a population of children with respiratory symptoms, skin-prick testing within individuals is highly repeatable over the short term, but poorly repeatable over a 2 year period. However, the percentage agreement in skin-prick test status for the group as a whole was high (82%). While no child became unequivocally skin-test negative having been previously positive, a small number of children changed status from negative to unequivocally positive, suggesting a genuine but small (4%) increase in the prevalence of skin-test positivity in this population.

Allergens↗