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Declan Lyons

Publications and source records attributed to Declan Lyons.

8 recordsLinked to original sources

A review of approaches to mobility telemonitoring of the elderly in their living environment.

Rapid technological advances have prompted the development of a wide range of telemonitoring systems to enable the prevention, early diagnosis and management, of chronic conditions. Remote monitoring can reduce the amount of recurring admissions to hospital, facilitate more efficient clinical visits with objective results, and may reduce the length of a hospital stay for individuals who are living at home. Telemonitoring can also be applied on a long-term basis to elderly persons to detect gradual deterioration in their health status, which may imply a reduction in their ability to live independently. Mobility is a good indicator of health status and thus by monitoring mobility, clinicians may assess the health status of elderly persons. This article reviews the architecture of health smart home, wearable, and combination systems for the remote monitoring of the mobility of elderly persons as a mechanism of assessing the health status of elderly persons while in their own living environment.

Aged↗

Treatment of vasodepressor carotid sinus syndrome with midodrine: a randomized, controlled pilot study.

OBJECTIVES: To evaluate the efficacy of treatment of the vasodepressor form of carotid sinus hypersensitivity (carotid sinus syndrome (CSS)) with midodrine. DESIGN: A prospective, double-blind, randomized, controlled trial of crossover design. SETTING: A dedicated outpatient facility with access to tilt-table, digital arterial photoplethysmography, and 24-hour ambulatory blood pressure (BP) monitoring equipment. PARTICIPANTS: Ten older adults (4 male, 6 female, mean age 75, range 66-86 years) with a history of unexplained syncope who displayed an asymptomatic decrease in systolic BP (SBP) of more than 50 mmHg or a symptomatic decrease of more than 30 mmHg within 30 seconds of carotid sinus massage (CSM). MEASUREMENTS: Symptom reproduction and BP and heart rate changes were evaluated after CSM in supine and semierect positions on the right and then left sides. These measurements were performed on the final day of placebo and active-treatment phases. Ambulatory 24-hour BP monitoring took place on the penultimate and final days of each treatment phase. RESULTS: Eight patients were symptomatic after their initial CSM. The mean+/-standard deviation SBP decrease after initial CSM was 54+/-22 mmHg. Initial mean 24-hour ambulatory BP was 127/70+/-7/5 mmHg. Eight patients reported symptoms after CSM at the end of the placebo phase. The mean SBP decrease at the end of the placebo phase was 49+/-12 mmHg. The mean 24-hour ambulatory BP was 127/69+/-9/7 mmHg. One patient reported symptoms after CSM at the end of the active-treatment phase. The mean SBP decrease at the end of the active-treatment phase was 36+/-9 mmHg. The mean 24-hour ambulatory BP at the end of the treatment phase was 133/75+/-7/6 mmHg. The differences in symptom reporting and mean SBP decrease after CSM were both significant (P<.01 and P=.03, respectively). CONCLUSION: The results of this pilot study suggest that treatment of vasodepressor CSS with midodrine significantly reduced the rate of symptom reporting and attenuated SBP decreases after CSM but increased mean 24-hour ambulatory BP.

Accidental Falls↗

Does the crack silently break the back? Long-term follow-up and assessment of risk factors for regional osteoporosis following tibial shaft fractures.

The aim of this study is to determine the incidence and to quantify the risk factors for developing long-term regional osteopenia/osteoporosis (RO) following tibial fractures. We studied 42 adult subjects (8 females and 34 males) who had sustained a tibial fracture 16 yr prior to the study. Mechanism and type of injury, method of treatment, length of immobilization, weight-bearing status, and healing time were determined from the patient records. A questionnaire covering known causes of generalized osteoporosis (GO), including history of smoking, alcohol consumption, medications, other fractures, thyroid/parathyroid disorders, epilepsy, and renal disorders, was answered by all the subjects. Bone mineral density (BMD) of lumbar vertebrae 1-4 and both proximal femurs was assessed using dual-energy X-ray absorptiometry (DXA) scanning. T- and Z-scores were generated. Assessment of risk factors was done by calculating the odds ratio (OR) and 95% confidence interval (CI). The incidence of significant loss of BMD as defined by the World Health Organization (T-score <-1) of the ipsilateral neck of femur and/or lumbar spine was found to be 40%. None of our subjects had any known cause for GO. The following risk factors were found to be statistically significant in unadjusted models: smoking (OR 22, 95% CI = 4 - >40), alcohol >20 units/wk (OR 11, 95% CI 2 = 2-54), open fracture (OR 17, 95% CI = 2.9 - >40), nonweight bearing >4 wk (OR 15, 95% CI 2.9- >40), and delayed union defined as healing time more than 6 mo (OR 15, 95% CI 1.54 - >40). Permanent regional loss of BMD occurs in a significant proportion of tibial shaft fracture patients. Modern fracture management should include identifying "at-risk" patients and appropriate preventive measures to prevent fragility fractures.

Absorptiometry, Photon↗

Orthostatic tolerance in older patients with vitamin B12 deficiency before and after vitamin B12 replacement.

Orthostatic hypotension (OH) and vitamin B12 deficiency are common disorders in older people. Several case series have reported an association between vitamin B12 deficiency and OH. The effect of vitamin B12 replacement on this dysfunction has not been studied. We prospectively studied responses to head up tilt in patients over 70 years with vitamin B12 deficiency (intervention group) and compared their responses after replacement to those of matched patients with idiopathic OH and normal serum vitamin B12 concentrations (control group). Blood pressure (BP), heart rate (HR) and systemic vascular resistance (SVR) changes during orthostatic stress were evaluated using digital artery photoplethysmography. Eight patients and eight controls were studied. Initial head up tilt produced a mean BP decrease of 44/29 mmHg (s.e.m. 4/4 mmHg) in the intervention group and 33/12 mmHg (s.e.m. 3/2 mmHg) in the control group. Repeat head up tilt 6 months after vitamin B12 replacement produced a mean BP decrease of 15/9 mmHg (s.e.m. 5/2 mmHg) in the intervention group. The mean decrease in the control group was 30/12 mmHg (s.e.m. 2/2 mmHg). The difference in BP decreases between groups was statistically significant for both systolic and diastolic BP (p < 0.001 for both systolic BP and diastolic BP). Mean SVR in the intervention group decreased by 658 dynes/cm5/sec (s.e.m. 74 dynes/cm5/sec) during initial head up tilt. Mean SVR during repeat head up tilt decreased by 79 dynes/cm5/sec (s. e. m. 12 dynes/cm5/sec). Mean SVR in the control group decreased by 158 dynes/cm5/sec (s. e. m. 10 dynes/cm5/sec) during initial head up tilt and by 258 dynes/cm5/sec (s. e. m. 31 dynes/cm5/sec). The difference in SVR changes between groups was statistically significant (p = 0.02). We conclude that replacing vitamin B12 in older patients with vitamin B12 deficiency is associated with improved orthostatic tolerance to head up tilt.

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Differences in the behavioral and psychological symptoms between Alzheimer's disease and vascular dementia: are the different pharmacologic treatment strategies justifiable?

BACKGROUND: This study aimed (1) to compare the behavioral and psychological symptoms of dementia (BPSD) between patients with Alzheimer's disease (AD) and vascular dementia (VaD); (2) to investigate the differences in the correlates of BPSD between them; and (3) to suggest potential different pharmacological strategies in treating BPSD of either etiology. METHODS: In a study group of 135 patients with dementia (99 AD, 36 VaD), information on age, gender, education, age at onset and duration of dementia was collected. The severity of dementia was measured by the following assessment scales: Korean version of Mini-Mental State Examination (MMSE-K) for cognitive function; Blessed Dementia Scale (BDS) for functional activities of daily living (ADL); Barthel Index (BI) for physical ADL; and Brief Psychiatric Rating Scale (BPRS), Hamilton Depression Scale (HAM-D) and Hamilton Anxiety Scale (HAM-A) for BPSD. The independent variables between the patients with AD and VaD were compared, and then the correlations of BPSD with other variables were estimated. RESULTS: HAM-D and HAM-A scores were higher in patients with VaD than in those with AD, while other variables demonstrated no statistical differences. BPRS score correlated with scores on MMSE-K, BDS and BI in AD, but only with BDS in VaD. The HAM-D score correlated with scores on BDS and BI in AD, but only with BDS in VaD. The HAM-A score was correlated with score on BDS in AD not in VaD. CONCLUSIONS: BPSD were more severe in the patients with VaD. However, BPSD correlated more prominently with cognitive or ADL impairments in patients with AD. Different treatment approaches to BPSD may be required according to the clinical differentiation of dementia type.

Aged↗

Paradoxical vasodilation during lower body negative pressure in patients with vasodepressor carotid sinus syndrome.

OBJECTIVES: To elucidate the pathophysiological mechanism of the vasodepressor form (VD) of carotid sinus syndrome (CSS) by maneuvers designed to induce generalized sympathetic activation after baroreceptor unloading (lower body negative pressure, LBNP) or direct peripheral adrenoreceptor stimulation via local administration of norepinephrine (NA). DESIGN: Subjects were identified with VD of CSS through diagnostic testing. SETTING: Research laboratory. PARTICIPANTS: Eleven young controls (YC) (mean age +/- standard error of mean = 22.8 +/- 0.7), eight elderly controls (EC) (72.6 +/- 0.6), and eight elderly patients with VD (78.7 +/- 1.7). MEASUREMENTS: Forearm arterial blood flow (FABF) was measured in the left and right arms by venous occlusion plethysmography. Measurements were performed during baseline conditions, LBNP (-20 mmHg), and intra-arterial NA infusion in the left brachial artery at three progressively increasing rates (60, 120, and 240 pmol/min). RESULTS: During LBNP, FABF significantly decreased in YC (baseline 3.61 +/- 0.30 vs -20 mmHg 2.96 +/- 0.24 mL/100 g/min, P =.030) and EC (4.05 +/- 0.74 vs 3.69 +/- 0.65 mL/100 g/min, P =.033) but increased in elderly patients with VD (3.65 +/- 0.60 vs 4.54 +/- 0.80 mL/100 g/min, P =.020). During NA infusion, a significant forearm vasoconstriction occurred in YC (FABF left:right ratio 1.00 +/- 0.05 at baseline; 0.81 +/- 0.08 at 60 pmol/min, P =.034; 0.81 +/- 0.05 at 120 pmol/min, P <.001; 0.72 +/- 0.04 at 240 pmol/min, P <.001), whereas no significant FABF changes were observed in EC (1.04 +/- 0.06; 0.96 +/- 0.07, P =.655; 0.89 +/- 0.10, P =.401; 0.94 +/- 0.10, P =.590) or elderly patients with VD (1.04 +/- 0.06; 1.16 +/-0.10, P =.117; 1.04 +/- 0.08, P =.602; 1.11 +/- 0.10, P =.305). CONCLUSION: VD of CSS is associated with a paradoxical vasodilatation during LBNP and an impairment of peripheral alpha-adrenergic responsiveness, which may be age-related.

Adrenergic alpha-Agonists↗

Postprandial hypotension.

Postprandial hypotension is a prevalent condition in the elderly population and seems to be more common in frail elderly individuals who may be more susceptible to complications such as syncope and falls. Diagnosis is relatively easy and may be reversible in many cases. The epidemiology and pathophysiology of postprandial hypotension are not defined fully; however, a number of pathologic processes likely are involved, including abnormal sympathetic function, baroreceptor function, and vasoactive peptide release and activity. The precise relationship between symptoms and postprandial reductions in blood pressure is unclear. Blood pressure maintenance after a meal may depend on the interaction of some or all of the mechanisms outlined previously to compensate for the increase in bowel blood volume. The impairment of one or more of these mechanisms could result in inadequate compensation that leads to hypotension. If so, the presence of symptoms depends on that individual patient's ability to exercise adequate compensatory cerebral autoregulation. A hypertensive elderly patient may experience symptoms with only a small reduction in blood pressure, whereas a patient with autonomic failure may require a much larger fall in blood pressure to occur before they become symptomatic. The current definition of postprandial hypotension uses a threshold of 20 mm Hg as a cut off for diagnosis, but this may not be relevant to the presence or absence of symptoms. Further epidemiologic data are needed. Additionally, there is a lack of controlled trial evidence for the drugs that are used to treat this condition, and treatment often is carried out on a trial-and-error basis. Further research must be performed to identify the specific pathophysiology in certain patient groups, such as elderly hypertensive patients and those with autonomic failure, and to identify effective pharmacologic therapies that can be supported by randomized, placebo-controlled trials.

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