331 THE USE OF BODY MASS INDEX IN PREDICTING ORTHOSTATIC HYPOTENSION IN OLDER ADULTS

Background

The presence of Orthostatic Hypotension (OH) is known to be associated with an increased mortality risk. Previous Irish research has shown that elevated Body Mass Index (BMI) may be protective against OH, with overweight and obese patients having significantly smaller Systolic Blood Pressure (SBP) drops during Head-Up-Tilt (HUT) Testing.

Methods

Demographics, including age, height and weight, were obtained retrospectively from all head up tilt testing performed in a tertiary Irish hospital between 2000 and 2021. All incomplete records were excluded. A total of 4,717 patients were analysed. Linear regression models were used to examine the relationship between BMI and change in tilt SBP.

Results

2,089 males and 2,628 females over the age of 60 years old were examined. The mean age is 77 years ± 7.8 (S.D.), with majority (51.5%) of the cohort overweight or obese. 69.7% of individuals demonstrated OH. The mean change in tilt SBP was –7mmHg in the underweight and healthy weight group, and –10mmHg in the overweight or obese group. The linear regression model established that BMI significantly predicted a change in tilt SBP (beta=0.394, 95% CI: 0.235 to 0.554, p<0.001), but remains a poor predictive variable (R2=0.004) for this cohort. This correlation was similar for both genders (male: r=0.08, female: r=0.07).

Conclusion

Our findings confirmed a correlation between BMI and its predictive impact on OH in older adults. Future studies should explore targeted populations with multivariate analysis, taking into consideration age and gender, to reduce the heterogeneity of data.

220 RELATIONSHIP BETWEEN HEIGHT AND SYSTOLIC BLOOD PRESSURE IN OLDER ADULTS

Background

Hypertension is common amongst older adults in Ireland and is a major risk factor for both ischaemic and haemorrhagic stroke. Several studies have investigated the relationship between height and hypertension, however results have been inconsistent. In our Irish tertiary hospital patients undergoing tilt table testing have resting blood pressure measured prior to the test, and height recorded. Our aim was to assess whether there is a relationship between height and resting Systolic Blood Pressure (SBP) in patients aged over 60 years.

Methods

All tilt table test results between 2000 and 2021 in a single centre were reviewed retrospectively, collecting data on age, height and resting SBP. Any incomplete records were excluded, as were those from patients under 60 years old. Linear regression modelling was used to assess relationship between height and resting SBP.

Results

A total of 4,729 complete records were included for patients over 60 years old. 2630 (61.5%) of the patients were female. Mean age was 77 ± 7.8 years. 57.7% patients had either an elevated resting systolic and/or diastolic BP ≥130/80 and 28.4% ≥140/90. The linear regression model established that while height could be used to predict resting systolic blood pressure (beta=-0.166, 95% CI: –0.219 to –0.113, p<0.001), height only accounted for 0.8% of variability in resting SBP (R2 = 0.008).

Conclusion

Our large dataset establishes an association but no meaningful causation between height and resting systolic blood pressure. Current antihypertensive treatment was not recorded, which may have affected the results. Future studies will include further multivariate analysis accounting for antihypertensive use and other factors that may impact hypertension such as age, weight and gender.

Mass and the Dangers of Syncope

Introduction Syncope is defined as a transient, self-limited loss of consciousness with an inability to maintain postural tone that is followed by spontaneous recovery. We revisit situational syncope focusing on one situation, Mass. Methods We interrogated our electronic syncope database for key terms associated with situational syncope. From the most commonly encountered situation, Mass, we interrogated the results of tilt testing performed to identify evidence of orthostatic hypotension. Results There were 110 cases of situational syncope identified with 56.3% (n=62) taking place at mass. All had tilt table testing performed and 15.4% (n=17) had evidence of orthostatic hypotension. Conclusion The multiple sudden changes in position during mass from sitting to kneeling to standing can precipitate an episode of orthostatic hypotension. Consideration should be given as to whether it is safe for older mass goers to be subjected to such significant orthostatic stress.

Dedicated Orthogeriatric Service Saves the HSE a Million Euro

Hip fracture is common in older adults and is associated with high morbidity, mortality and significant health care costs. A pilot orthogeriatrics service was established in an acute hospital. We aimed to establish the cost effectiveness of this service. Length of hospital stay, discharge destination and rehabilitation requirements were analysed for a one year period and compared to patients who received usual care prior to the service. We calculated the costs incurred and savings produced by the orthogeriatric service. Median length of stay was reduced by 3 days (p < 0.001) saving €266,976. There was a 19% reduction in rehabilitation requirements saving €192,600. Median rehabilitation length of stay was reduced by 6.5 days saving €171,093. Reductions in long term care requirements led to savings of €10,934 per week. Costs to establish such a service amount to €171,564. The introduction of this service led to improved patient outcomes in a cost effective manner.

The changing face of orthostatic and neurocardiogenic syncope with age

AIM

Reports of the outcomes of syncope assessment across a broad spectrum of ages in a single population are scarce. It is our objective to chart the varying prevalence of orthostatic and neurocardiogenic syncope (NCS) as a patient ages.

METHODS

This was a retrospective study. All consecutive patients referred to a tertiary referral syncope unit over a decade were included. Patients were referred with recurrent falls or orthostatic intolerance. Tilt tests and carotid sinus massage (CSM) were performed in accordance with best practice guidelines.

RESULTS

A total of 3002 patients were included (1451 short tilt, 127 active stand, 1042 CSM and 382 prolonged tilt). Ages ranged from 11 to 91 years with a median (IQR) of 75 (62-81) years. There were 1914 females; 1088 males. Orthostatic hypotension (OH) was the most commonly observed abnormality (test positivity of 60.3%). Those with OH had a median (IQR) age of 78 (71-83) years. Symptomatic patients were significantly younger than asymptomatic (P = 0.03). NCS demonstrated a bimodal age distribution. Of 194 patients with carotid sinus hypersensitivity, the median age (IQR) was 77 (68-82) years. Those with vasovagal syncope (n = 80) had a median (IQR) age of 30 (19-44) years. There were 57 patients with isolated postural orthostatic tachycardia syndrome. Of the total patients, 75% were female. They had a median (IQR) age of 23 (17-29) years.

CONCLUSION

We have confirmed, in a single population, a changing pattern in the aetiology of syncope as a person ages. The burden of disease is greatest in the elderly.

Sitting and standing blood pressure measurements are not accurate for the diagnosis of orthostatic hypotension

INTRODUCTION

Orthostatic hypotension (OH) is associated with troublesome symptoms and increased mortality. It is treatable and deserving of accurate diagnosis. This can be time consuming. The current reference standard for its diagnosis is head-up tilt (HUT) testing with continuous beat-to-beat plethysmography. Our objective was to assess the accuracy of sit-stand testing with semi-automatic sphygmomanometry for the diagnosis of OH.

DESIGN

Retrospective test of diagnostic accuracy.

METHODS

This was a retrospective study performed using a database maintained by a busy syncope unit. HUT testing was performed using an automated tilt table with Finometer monitoring. A 3 min 70 degrees HUT was performed following 5 min supine. Sitting blood pressure (BP) was measured following 3 min rest. Standing BP was measured within 30 s of assuming the upright posture. The results of sit-stand testing were compared with HUT testing as a reference standard. Both tests happened within 5 min of each other and patients underwent no intervention between tests.

RESULTS

From a total of 1452 consecutive HUTs, we identified 730 with pre-test measures of sitting and standing BP. The mean age of this group was 70.57 years (SD = 15.1), 62% were female. The sensitivity of sit-stand testing was calculated as 15.5%, specificity as 89.9%, positive predictive value as 61.7%, negative predictive value as 50.2% and the likelihood ratio as 1.6. The area under the Receiver Operator Curve was 0.564.

CONCLUSION

We have demonstrated that sit-stand testing for OH has very low diagnostic accuracy. We recommend that the more time-consuming reference standard method of diagnosis be used if the condition is suspected.

Orthostatic hypotension: a new classification system

AIMS

Orthostatic hypotension (OH) is a common condition, which is defined as a reduction in systolic blood pressure of >or=20 mmHg or diastolic blood pressure of >or=10 mmHg within 3 min of orthostatic stress. Utilizing total peripheral resistance (TPR) and cardiac output (CO) measurements during tilt-table testing (Modelflow method), we classified OH into three categories, namely arteriolar, venular, and mixed. The principle defect in arteriolar OH is impaired vasoconstriction after orthostatic stress, reflected by absence of the compensatory increase in TPR. In venular OH, the predominant defect is excessive reduction in venous return, reflected by a large drop in CO after orthostatic stress with marked tachycardia. Mixed OH is due to a combination of both these mechanisms.

METHODS AND RESULTS

We analysed haemodynamic parameters of 110 patients with OH and categorized them as arteriolar, venular, or mixed. Significant differences between the groups were found for the magnitude and time to reach nadir of the systolic blood pressure drop post-head-up tilt. The mixed OH category had the largest systolic blood pressure reduction (42.5, 31.9, 53.3 mmHg, P < 0.001) and the longest nadir time (18.6, 20, 30.7 s, P = 0.002).

CONCLUSION

This is a practical classification tool and when validated physiologically, this system could be useful in directing treatment of OH.