Gait velocity in senior people. An easy test for detecting mobility impairment in community elderly.

BACKGROUND: Functional assessment is an important part of the evaluation of elderly patients. Mobility problems detected by functional tests predict the development of more severe disability and injurious events such as falls and hip fractures. Several tests to evaluate mobility have been described, but most of them are difficult to perform by a primary care physicians or take much time in the ambulatory setting. PURPOSE: To evaluate different mobility test to detect mobility impairment in community senior people. Select an easier test to perform on the ambulatory ward by a GP with the hypothesis that gait velocity could be an easier test to detect early mobility impairment. METHODS: A cohort of 100 elderly subjects of 75 year and older were selected from our database and contacted by phone. The subjects were appointed and assessed by three geriatricians from January to May 2000. The measures including MMSE, Yesavage Test, ADL (Barhtel) and IADL (Lawton), the Get Up and Go test, the POMA, one leg balance test and the Gait Velocity (GV). A gait velocity of 0.8 m/s or lower was defined as a pathological gait velocity (PGV). RESULTS: 95 subjects, mean age 79.63 (+/- 4) ranged form 75 to 95. Women in 71.3%. The ADLs were normal on 85% of the patients and the MMSE was normal on 78%. There was a significant association between pathological gait velocity (<0.8m/sec) and impairment on Get up and Go (OR 2.20; 95% CI 1.44-3.34), incapacity to perform the one leg balance test (OR 2.20; 95%CI: 1.43 - 4.71) and abnormal POMA test (OR 4.60; 95 %CI 1.5-14.7). Only 15% of the subjects with normal gait velocity reported recurrent falls in the previous 6 months while 35% of subjects with pathological gait velocity did. (OR 0.32 CI95% 010-099 p < 0.044). CONCLUSION: The pathological gait velocity (<0.8m/sec) correlates with a pathologic performance of Get Up and Go test and POMA and with the incapacity to perform the One Leg Balance test. Also correlate with previous repeated falls in the last 6 (p <0.04). The gait velocity could be a test easy to perform, no time consuming, and an operative tool to apply in the ambulatory care to detect elderly patients with mobility impairment.

Lack of effective blood pressure control among an elder hypertensive population in Buenos Aires.

Our purpose was to determine the level of awareness, treatment, and control of hypertension in a population of subjects aged 65 or more. We studied a random sample from the national health care program in Buenos Aires. Letters were mailed to 1000 selected individuals. Among those eligible, 41.4% (n = 414) were enrolled. The mean age was 73.8 years and 68% were women. Prevalence of hypertension in our sample was 77.5% (n = 321). Awareness of hypertension was 60.7% (n = 195). Fifty-four percent (n = 173) of the hypertensive subjects were receiving pharmacologic treatment and only 18.5% (n = 32) of them were controlled. These results show that there is a low level of awareness, pharmacologic treatment, and control of hypertension in the studied elderly subjects.

Diastolic pressure underestimates age-related hemodynamic impairment.

It has been hypothesized that as large arteries become more rigid with age, the pattern of hypertension changes from diastolic to systolic. Thus, diastolic blood pressure (DBP) may lose its ability to reflect the increase in vascular resistance with age. To assess this, we studied the age-related changes in blood pressure pattern and its steady-state and pulsatile determinants. We performed an epidemiological analysis based on a national survey of 10,462 subjects from Argentina. A hemodynamic analysis (impedance cardiography) was then carried out in 636 consecutive hypertensive patients (age, 25 to 74 years). Whereas the rate of increment in the prevalence of mild to moderate hypertension (MMH) reached a plateau after the sixth decade, isolated and borderline systolic forms of hypertension began a steep and sustained rise. Among patients with MMH, DBP remained stable from the third to the seventh decade, whereas SBP maintained a sustained increase. Despite similar DBP, the systemic vascular resistance index increased 47% (P<.01) and the cardiac index decreased 27% (P<.01), whereas the ratio of stroke volume to pulse pressure, an index of arterial compliance, decreased 45% (P<.01). However, there were no significant differences between older patients with MMH and those with isolated systolic hypertension in the level of SBP, vascular resistance, stroke volume, and cardiac index. Compared with age-matched normotensive control subjects, the ratio of stroke volume to pulse pressure was much more reduced in isolated systolic hypertension (48%) than in MMH (30%). In summary, the present study, carried out in a large sample of hypertensive subjects with a wide age range, showed a simultaneous impairment in vascular resistance and arterial compliance associated with aging in different patterns of hypertension. The magnitude of these changes, with opposite effects on DBP but additive effects on SBP, suggests that a hemodynamic mechanism could determine the transition in the prevalence of diastolic hypertension toward a systolic pattern of hypertension with aging. Also, the results suggest that SBP, but not DBP, is a reliable indicator of the underlying hemodynamic abnormalities (high resistance and low arterial compliance) in the elderly.

Role of atrial natriuretic factor, hemodynamic changes and renal nerves in the renal effects of intraperitoneal morphine in conscious rats.

The aim of the present study was to investigate the role of renal nerves and atrial natriuretic factor (ANF) in the mechanisms responsible for the diuresis and antinatriuresis induced by morphine in rats in a normal state of hydration. Male Wistar rats weighing 350-400 g were divided into two groups: one group was subjected to bilateral renal denervation, whereas the other consisted of sham-operated controls. The animals were placed in individual metabolic cages, and morphine (1.25, 2.5, 5.0 or 10.0 mg/kg body weight) or vehicle (0.5 ml isotonic saline) was injected intraperitoneally. Urine was collected hourly for 1 h before and 3 h after morphine injection. The lower doses of morphine (1.25 and 2.5 mg/kg body weight) induced a transient increase in urine output (from 1.17+/-0.12 to 2.49+/-0.34 and from 0.78+/-0.08 to 1.71+/-0.18 microl/min, respectively). The diuretic response to these doses was similar in bilaterally denervated rats. Higher doses (5.0 and 10.0 mg/kg body weight) induced a marked but transient reduction in the urinary flow rate during the first hour (from 0.90+/-0.11 to 0.48+/-0.05 and from 1.37+/-0.17 to 0.45+/-0.08 microl/min, respectively), followed by a delayed diuretic effect. The antidiuretic action of morphine was not observed in bilaterally denervated rats. In control rats, morphine induced a dose-dependent decrease in sodium excretion 1 h after administration, an effect that was blunted in the denervated group. The lower morphine doses (1.25 and 2.5 mg/kg body weight) elicited a transient increase in the glomerular filtration rate (GFR) in both control (from 1.23+/-0.12 to 1.67+/-0.17 and from 1.28+/-0.14 to 2.41+/-0.18 ml/min) and bilaterally denervated rats (from 1.29+/-0.14 to 1.66+/-0.17 and from 1.18+/-0.22 to 1.72+/-0.19 ml/min), whereas the higher doses (5.0 and 10.0 mg/kg body weight) produced a marked, transient GFR decrease in the controls (from 1.25+/-0.11 to 0.43+/-0.05 and from 1.13+/-0.17 to 0.47+/-0.08 ml/min) and bilaterally denervated animals (from 1.48+/-0.16 to 0.74+/-0.09 and from 1.22+/-0.15 to 0.73+/-0.06 ml/min), although the reduction was less pronounced with renal denervation. Morphine induced a transient, dose-dependent reduction in blood pressure (from 114+/-1 to 71+/-6 mm Hg at 10.0 mg/kg body weight) and a dose-dependent elevation of plasma ANF. No differences in plasma ANF were observed between control and denervated animals under basal conditions (60+/-7 vs. 42+/-6 pg/ml) or after injection of 2.5 or 5.0 mg/kg of morphine (155+/-11 vs. 167+/-9 and 360+/-9 vs. 401+/-9 pg/ml, respectively). Our data suggest that the renal responses to intraperitoneal morphine administration derive from the integration of several different actions: (1) increased ANF release; (2) decreased arterial pressure; (3) subsequent activation of renal sympathetic activity, and (4) the direct effect of morphine on tubular function.