The prevalence and pathological correlates of orthostatic hypotension and its subtypes when measured using beat-to-beat technology in a sample of older adults living in the community.

BACKGROUND: beat-to-beat technology is increasingly used for investigating orthostatic intolerance (OI) but the prevalence of orthostatic hypotension (OH) diagnosed with this technology is unclear. OBJECTIVES: (i) to use beat-to-beat technology to define the prevalence of OH, (ii) to investigate the pathological correlates of OH, (iii) to report the diversity of postural BP responses. METHODS: cross-sectional study of adults ≥ 65 years. BP responses to a 3-min head-up tilt were analysed. RESULTS: of 326 participants, 203(62.3%) were females. The median (IQR) age was 73 (70-78). One hundred and ninety-one (58.6%) met standard (20 mmHg systolic/10 mmHg diastolic) criteria for OH. The prevalence was higher in females (60.1% F versus 56.1% M); 47% were arteriolar subtype, 33% were venular, 9% were mixed and 11.0% could not be classified. Morphological analysis identified 102 subjects with 'small drop, overshoot', 131 with 'medium drop, slow recovery' and 31 with 'large drop, nonrecovery'. Those with OH had a lower BMI (P = 0.02), a higher resting heart rate (P = 0.005), were more likely to take a psychotropic (P = 0.02), have vertigo (P = 0.004) and report OI (P = 0.02). The 95th centile for the duration of systolic BP (SYSBP) decay >20 mmHg was 175 s and the slope of systolic BP decay was 4.75 mmHg/s. The 5th centile for percentage recovery of SYSBP was 81.4%. CONCLUSION: (i) beat-to-beat methods identify a higher prevalence of OH than sphygmomanometry, (ii) the pathological correlates of OH diagnosed in this manner are similar to those described for sphygmomanometry, (iii) there is a diverse pattern of orthostatic BP decay that could be used in future research to predict adverse outcomes in OH.

Specialist medication review does not benefit short-term outcomes and net costs in continuing-care patients.

OBJECTIVES: to evaluate specialist geriatric input and medication review in patients in high-dependency continuing care. DESIGN: prospective, randomised, controlled trial. SETTING: two residential continuing care hospitals. PARTICIPANTS: two hundred and twenty-five permanent patients. INTERVENTION: patients were randomised to either specialist geriatric input or regular input. The specialist group had a medical assessment by a geriatrician and medication review by a multidisciplinary expert panel. Regular input consisted of review as required by a medical officer attached to each ward. Reassessment occurred after 6 months. RESULTS: one hundred and ten patients were randomised to specialist input and 115 to regular input. These were comparable for age, gender, dependency levels and cognition. After 6 months, the total number of medications per patient per day fell from 11.64 to 11.09 in the specialist group (P = 0.0364) and increased from 11.07 to 11.5 in the regular group (P = 0.094). There was no significant difference in mortality or frequency of acute hospital transfers (11 versus 6 in the specialist versus regular group, P = 0.213). CONCLUSION: specialist geriatric assessment and medication review in hospital continuing care resulted in a reduction in medication use, but at a significant cost. No benefits in hard clinical outcomes were demonstrated. However, qualitative benefits and lower costs may become evident over longer periods.

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.

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.

Underlying mechanisms of impaired visceral pain perception in older people.

There is increasing recognition that aging can have a profound effect on the presentation of illness. Older patients with diseases of visceral organs are much more likely than younger adults to present atypically. Examples are the frequent absence of pain in older patients with conditions such as myocardial infarction, peptic ulcer disease, and pneumothorax. Recent developments have helped elucidate the complex processes involved in signaling information from the effects of noxious stimuli on visceral organs, but understanding of why older patients with visceral disease are more likely to present without pain is still rudimentary. Much of the previous experimental evidence on age-related differences relates to somatic rather than visceral sources of pain. As a result, it may not have direct comparability with transmission of information on visceral damage or noxious stimulation. This article reviews the published pathophysiological data on sensory transmission from visceral organs. Where possible, this is correlated with other published clinical studies on age-related differences in visceral pain perception. Areas in which experimental evidence is absent are also highlighted. Finally suggestions are made as to how newer experimental and neuroimaging techniques may help to increase understanding of this complex subject and its resulting clinical applicability.