Prevalence of advance care directives in the community: a telephone survey of three Australian States.

BACKGROUND: The community prevalence of advance care directives (ACD) is low despite known benefits of advance care planning for patients, families and health professionals. AIM: To determine the community prevalence of instructional and appointing ACD in New South Wales, Victoria and Queensland and factors associated with completion of these documents. METHODS: A telephone survey of adults living in New South Wales, Victoria and Queensland (n = 1175) about completion of instructional ACD (making their own decisions about future healthcare) and appointing ACD (appointing another to decide). Quota sampling occurred based on population size by state, gender and age, with oversampling in smaller jurisdictions (Victoria and Queensland). RESULTS: Overall response rate was 33%. Six per cent of respondents reported completing an instructional ACD while 12% reported completing an appointing ACD. Female gender, higher educational level, personal experience of a major health scare and being widowed were significant predictors of completing an instructional ACD. Older age, higher educational level and being widowed were significant predictors of completing an appointing ACD. CONCLUSIONS: Despite long-standing efforts to increase advance care planning, community prevalence of ACD remains low, particularly for instructional ACD. This study found some different predictors for instructional ACD compared with appointing ACD, and also a potential role for experiential factors in triggering uptake. These findings suggest supplementing general community awareness campaigns with more nuanced and targeted efforts to improve ACD completion.

Community Knowledge of Law on End-of-life Decision-making: An Australian Telephone Survey.

The law has a clear role to play in supporting patients and their substitute decision-makers (SDMs) to be involved in end-of-life (EOL) decision-making. Although existing literature suggests that knowledge of EOL law is variable among health professionals, there is little information about the extent and sources of such knowledge within the general community. A telephone survey of a representative sample of adults in three Australian States used six case scenarios to examine the extent to which adults know their legal duties, rights and powers as patients or SDMs; the sources from which people derive relevant legal knowledge; experiences of EOL decision-making; and individual characteristics associated with levels of knowledge. The results show considerable variation in levels of legal knowledge dependent primarily of the area of decision-making presented, some sizeable gaps in people's knowledge of EOL law, and varied awareness of how to access appropriate information on this subject. This study points to the need to increase community legal literacy around EOL decision-making, enhance awareness of the role of law in these circumstances and promote the availability of reliable and accessible information on the law at the time when it is needed.

HIV neuropathy: an in vivo confocal microscopic study.

Several approaches exist for quantitative assessment of human immunodeficiency virus (HIV)-associated distal sensory polyneuropathy (DSP). While useful, each has some limitations. This study evaluated non-invasive, in vivo reflectance confocal microscopy (RCM) of Meissner corpuscles (MCs) as a measure of HIV-DSP. Forty-eight adults (29 HIV-infected, 19 controls) underwent RCM of MC density (MCs/mm(2)) at the arch, fingertip, and thenar eminence (TE); ankle skin biopsy to measure epidermal nerve fiber density (ENFD); electrophysiologic studies; and tactile, vibration, and thermal threshold testing. HIV+ subjects were clinically categorized as having DSP signs or no signs. MC densities were lower in HIV+ subjects with DSP signs than in controls (arch, p = 0.0003; fingertip, p < 0.0001; TE, p = 0.0002). Tactile thresholds in the TE and foot were worse in HIV-DSP than in controls, but in this mild DSP cohort, sural amplitudes, ENFD, and vibration and thermal thresholds did not differ significantly from controls. Fingertip MC densities and tactile thresholds at the foot were also lower in HIV+ subjects without DSP signs than in controls. Other sensory measures were not significantly different in HIV+ subjects without DSP signs than in controls. MC density correlated inversely with tactile thresholds at each imaging location. The results suggest that RCM of MC density complements existing sensory DSP measures and discriminates mild HIV-DSP from controls at a stage when sural amplitudes do not. Further studies are required to determine whether RCM of MC density can establish quantitative changes in DSP, in response to treatment or disease progression.

In vivo confocal microscopy of Meissner corpuscles as a novel sensory measure in CMT1A.

Reliable, valid, and responsive outcomes for different aspects of Charcot-Marie-Tooth (CMT) neuropathy have become increasingly important in an emerging era of therapy development. Measures of the sensory component of CMT in particular are limited. One novel approach with potential applicability to CMT is non-invasive in vivo reflectance confocal microscopy (RCM) of Meissner corpuscles (MCs). In this prospective study, we evaluated MC densities using RCM, and touch-pressure and vibration sensation thresholds in a cohort of Charcot-Marie-Tooth type 1A (CMT1A) subjects with comparison to healthy controls. MC density was lower in CMT1A subjects than in controls at the fingertip (digit V) (2.59 ± 2.73 MCs/mm(2) vs. 6.77 ± 3.68 MCs/mm(2) , p = 0.001), but not more proximally at the thenar eminence. Touch-pressure thresholds were higher in CMT1A than in controls at digit V (p = 0.002) and at the thenar eminence (p = 0.0001). Vibration thresholds in CMT1A at digit V were also higher than in controls (p = 0.0001). A lower MC density at digit V was associated with greater global CMT severity as reflected by the Charcot-Marie-Tooth neuropathy score (CMTNS) (r = -0.76, p = 0.004) and the Neuropathy impairment score (NIS) (r = -0.73, p = 0.007). Similarly, worse touch-pressure thresholds at the fingertip (digit V) were associated with more severe CMT1A on the CMTNS (r = 0.71, p = 0.009) and NIS (r = 0.70, p = 0.011). Vibration thresholds at digit V were not associated with either the CMTNS (r = 0.11, p = 0.74) or NIS (r = 0.21, p = 0.52). Non-invasive in vivo RCM of MC density at the hand and the evaluation of touch-pressure thresholds show promise as measures of sensory structure and function in CMT1A.

In-vivo reflectance confocal microscopy of Meissner's corpuscles in diabetic distal symmetric polyneuropathy.

OBJECTIVE: To evaluate in-vivo reflectance confocal microscopy (RCM) of Meissner's corpuscles (MC) in diabetic distal symmetric polyneuropathy (DSP). METHODS: Forty-three adults with diabetes and 21 control subjects underwent RCM of MC density at the fingertip of digit V, thenar eminence (TE), and arch of the foot, ankle skin biopsy for epidermal nerve fiber density (ENFD), electrophysiological studies, monofilament threshold testing, and timed vibration at the toe. Subjects with diabetes were subdivided into groups with and without clinical DSP using the American Academy of Neurology (AAN) case definition and neuropathy outcomes were compared across groups. RESULTS: Both diabetic groups (with and without AAN clinical DSP criteria) had objective evidence of peripheral sensory involvement using conventional sensory measures, although those with clinical DSP criteria had greater abnormalities. MC densities were lower in the entire diabetic group at the TE and digit V relative to controls. MC densities at all imaging sites were associated with corresponding conventional sensory measures. MC densities were reduced in subjects without AAN clinical DSP criteria at the TE and digit V compared to controls whereas conventional upper limb sensory measures did not differ between these groups. CONCLUSIONS: In-vivo RCM of MC density at digit V is a non-invasive, painless, objective marker in diabetes that offers a window into early large fiber sensory nerve terminal loss. Further studies are needed to determine whether RCM of MCs can identify quantitative changes in DSP associated with disease progression or treatment.

Dissociation of Structural and Functional Integrities of the Motor System in Amyotrophic Lateral Sclerosis and Behavioral-Variant Frontotemporal Dementia.

BACKGROUND AND PURPOSE: This study investigated the structural and functional changes in the motor system in amyotrophic lateral sclerosis (ALS; n=25) and behavioral-variant fronto-temporal dementia (bvFTD; n=17) relative to healthy controls (n=37). METHODS: Structural changes were examined using a region-of-interest approach, applying voxel-based morphometry for gray-matter changes and diffusion tensor imaging for white-matter changes. Functional changes in the motor system were elucidated using threshold-tracking transcranial magnetic stimulation (TMS) measurements of upper motor-neuron excitability. RESULTS: The structural analyses showed that in ALS there were more white-matter changes in the corticospinal and motor-cortex regions and more gray-matter changes in the cerebellum in comparison to controls. bvFTD showed substantial gray- and white-matter changes across virtually all motor-system regions compared to controls, although the brainstem was affected less than the other regions. Direct comparisons across patient groups showed that the gray- and white-matter motor-system changes inclusive of the motor cortex were greater in bvFTD than in ALS. By contrast, the functional integrity of the motor system was more adversely affected in ALS than in bvFTD, with both patient groups showing increased excitability of upper motor neurons compared to controls. CONCLUSIONS: Cross-correlation of structural and functional data further revealed a neural dissociation of different motor-system regions and tracts covarying with the TMS excitability across both patient groups. The structural and functional motor-system integrities appear to be dissociated between ALS and bvFTD, which represents useful information for the diagnosis of motor-system changes in these two disorders.

Patient identification of the symptomatic impact of charcot-marie-tooth disease type 1A.

OBJECTIVE: The burden of Charcot-Marie-Tooth type 1A (CMT1A), the most common inherited peripheral neuropathy, including impact on patient quality of life (QOL) is not well understood. This study aims to qualitatively describe the range of symptoms associated with CMT1A and impact on QOL. METHODS: We performed qualitative interviews with 16 adult CMT1A patients. Each interview was analyzed using a qualitative framework technique to identify and index symptoms by theme. RESULTS: Sixteen patients provided 656 quotes. One hundred forty-five symptoms of importance were identified representing 20 symptomatic themes. Symptoms associated with difficulty with mobility and ambulation, specific activity impairment, and emotional distress were the most frequently mentioned. CONCLUSIONS: Multiple symptoms contribute to CMT1A disease burden, some previously underrecognized. Improved recognition of underrecognized symptoms will optimize patient care and QOL.

Conduction slowing in diabetic distal polyneuropathy.

The pathophysiologic significance of motor conduction slowing observed in diabetic distal symmetrical polyneuropathy (DSP) remains controversial. We have used multiple linear regression analysis of compound muscle action potential (CMAP) amplitude vs. motor conduction velocity (CV) and distal latency (DL) in 57 patients with diabetic DSP and 34 patients with amyotrophic lateral sclerosis (ALS) to determine whether motor conduction slowing in diabetic DSP is due mainly to loss of large axons as in ALS or whether there is an additional demyelinative component. We found amplitude-dependent slowing of CV and DL in both diabetic DSP and ALS in the upper and lower extremities, consistent with a loss of large myelinated fibers. However, in diabetic DSP, there was also significant amplitude-independent slowing in intermediate but not distal nerve segments, supportive of an additional demyelinative component. CMAP amplitude vs. CV and DL regression analyses using ALS as a control group for relatively pure axon loss may provide pathophysiologic information about motor nerves in other neuropathic disorders.