Waiting time for surgery influences the outcome in idiopathic normal pressure hydrocephalus - a population-based study

Deformation of brain in normal pressure hydrocephalus is more readily associated with slow vasomotion rather than heartbeat related pulsations of intracranial pressure

OBJECTIVE

Enlarged brain ventricles, compressed parasagittal cerebrospinal fluid spaces, steep callosal angle, dilated sylvian fissures and focal cortical sulcal dilatation are typical imaging features of idiopathic normal pressure hydrocephalus (iNPH). The pathophysiological mechanisms behind these morphological changes are poorly understood, but the hydrodynamic concepts of communicating hydrocephalus suggest that increased heartbeat related intracranial pulsations are involved in ventricular enlargement. In this cross-sectional study we analysed the association between the radiological findings of iNPH and the physiological intracranial pressure (ICP) waveform components.

METHODS

117 patients with suspected iNPH underwent computerised overnight ICP monitoring with calculation of heartbeat related ICP pulse wave amplitude (calculated in the frequency domain, AMP, and time domain, MWA), amplitude of respiration induced ICP waves (RESP), power of slow vasogenic waves (SLOW), and index of cerebrospinal compensatory reserve (RAP). Radiological morphological data was recorded from computed tomography using Evans Index (EI), frontal occipital horn ratio (FOHR), and disproportionately enlarged subarachnoid space hydrocephalus (DESH) score.

RESULTS

The strongest correlation was observed between SLOW and DESH (r = 0.44, p < 0.012). SLOW also correlated with ventricular size as measured with EI (r = 0.23, p = 0.045) and FOHR (r = 0.26, p = 0.037). ICP and RESP also correlated with DESH (r = 0.25, p = 0.037 and r = 0.25, p = 0.038, respectively). AMP and MWA were not correlated with the radiological data.

CONCLUSIONS

Mainly SLOW showed correlations with the morphological imaging features of iNPH. SLOW is influenced by vasomotion and intracranial compliance. This study suggests that the magnitude of ICP slow wave activity, but not ICP pulse component is related to the size of brain ventricles and DESH in iNPH.

Utility and Efficacy of a Virtual Normal Pressure Hydrocephalus Support Group

OBJECTIVE

Normal pressure hydrocephalus (NPH) is a neurodegenerative process for which our team previously demonstrated the efficacy of an in-person NPH support group. However, in this study, we aimed to examine the educational benefits and efficacy of a virtual NPH support group.

METHODS

Monthly virtual meetings were held from July 2022 to June 2023 for NPH patients and their friends/families. The format of each meeting consisted of a physician-led presentation, question and answer sessions, group discussions, and polls to evaluate the meeting. The survey included questions to gather participant demographics and evaluate the benefits of education, emotional well-being, and virtual format.

RESULTS

Over one year, 11 virtual support group meetings were held and attended by 343 participants. The average survey ratings for gained knowledge, self-efficacy, and satisfaction ranged from 4.15 to 4.60 on a five-point scale, demonstrating strongly positive outcomes since a score above 3 is considered favorable. In this study, patients reported improved education, coping and communication skills, and emotional support. We also demonstrated high participant satisfaction and continued interest in meetings.

CONCLUSIONS

This study demonstrates that virtual, physician-led support groups can be effective in providing education, emotional, and peer support for NPH patients and their friends/families. Improved knowledge and accessibility to educational and social resources can improve patient health outcomes by improving adherence to physician recommendations.

Gait characteristics in idiopathic normal pressure hydrocephalus: A controlled study using an inertial sensor system

BACKGROUND

Gait disturbance is the most pronounced symptom in idiopathic normal pressure hydrocephalus (iNPH). Some gait parameters have been previously described, but an in-depth description of the gait pattern is lacking. The aim was to quantitatively evaluate gait in iNPH patients before and after shunt surgery and compare it to healthy individuals (HI), and correlate it with functional tests preoperatively.

METHODS

In total, 47 patients and 42 HI were included. The patients were assessed with the iNPH scale (total, gait and balance domain scores were analyzed), the timed up and go test (TUG) and an inertial sensor gait analysis system, RehaGait®, pre- and postoperatively. The HI were assessed with TUG and RehaGait®. Gait variables were: stride length, stride duration, velocity, cadence, variability, stance, swing, single support, double support, step height, hip, knee and ankle joint angles.

RESULTS

Compared to HI, the main differences in the gait variables were: decreased stride length (p < 0.01), velocity (p < 0.01), swing time (p < 0.01), single support (p < 0.01), hip flexion (p < 0.01), heel strike angle (p < 0.01) and toe-off angle (p < 0.01). Step height was normalized postoperatively; all other variables remained significantly worse than the HI. There were strong correlations between stride length, velocity, heel strike angle, and toe-off angle and the functional gait tests, but no correlations for any variable and the balance domain score.

CONCLUSIONS

The patients walked with reduced hip flexion, heel strike angle and toe-off angle, and had shorter strides, decreased velocity, and increased time for swing and single support, compared to HI. Step height was the only gait variable normalized after shunt surgery. Ankle joint kinematics correlated strongly with the results in functional gait tests. More research is warranted about how gait speed affects other gait variables in iNPH.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04795089.

Depressive symptoms, functional impairment, and health-related quality of life in idiopathic normal pressure hydrocephalus: A population-based study

BACKGROUND

Maximising quality of life is a central goal for all healthcare, especially when dealing with dementing disorders. In this study we aimed to compare health-related quality of life (HRQoL), depressive symptoms and functional impairment between individuals with and without idiopathic normal pressure hydrocephalus (iNPH) from the general population.

METHODS

A total of 122 individuals, 30 with iNPH (median age 75 years, 67 females) underwent neurological examinations and computed tomography of the brain with standardised rating of imaging findings and clinical symptoms. The participants completed the Geriatric Depression Scale (GDS-15) and the HRQoL instrument EQ5D-5L. In addition, the modified Rankin Scale (mRS) was used to evaluate functional impairment.

RESULTS

Compared with participants without iNPH, those with iNPH reported a higher score on GDS-15 (median 3 vs 1) and mRS (median 2 vs 1) (p < 0.05). Further, those with iNPH rated lower on EQ5D-5L (index 0.79, VAS 70) than those without iNPH (index 0.86, VAS 80) (p < 0.05). In logistic regression models, low HRQoL was associated with more depressive symptoms, a higher degree of iNPH symptoms, and lower functional status.

CONCLUSIONS

In this population-based sample, those with iNPH had more depressive symptoms, lower functional status, and worse quality of life compared to those without iNPH. The strongest association with low HRQoL was found for depressive symptoms, functional level, and degree of iNPH symptoms. These results underline the value of shunt surgery because of its potential to reduce symptoms and disability in iNPH and therefore improve HRQoL.

Symptoms and signs did not predict outcome after surgery: a prospective study of 143 patients with idiopathic normal pressure hydrocephalus

OBJECTIVE

To determine the utility of symptoms, signs, comorbidities and background variables for the prediction of outcome of treatment in iNPH.

METHODS

A prospective observational study of consecutively included iNPH patients, who underwent neurological, physiotherapeutic and neuropsychological assessments before and after shunt surgery. The primary outcome measure was the total change on the iNPH scale, and patients were defined as improved postoperatively if they had improved by at least five points on that scale.

RESULTS

143 iNPH patients were included, and 73% of those were improved after surgery. None of the examined symptoms or signs could predict which patients would improve after shunt surgery. A dominant subjective complaint of memory problems at baseline was predictive of non-improvement. The reported comorbidities, duration of symptoms and BMI were the same in improved and non-improved patients. Each of the symptom domains (gait, neuropsychology, balance, and continence) as well as the total iNPH scale score improved significantly (from median 53 to 69, p < 0.001). The proportions of patients with shuffling gait, broad-based gait, paratonic rigidity and retropulsion all decreased significantly.

DISCUSSION

This study confirms that the recorded clinical signs, symptoms, and impairments in the adopted clinical tests are characteristic findings in iNPH, based on that most of them improved after shunt surgery. However, our clinical data did not enable predictions of whether patients would respond to shunt surgery, indicating that the phenotype is unrelated to the reversibility of the iNPH state and should mainly support diagnosis. Absence of specific signs should not be used to exclude patients from treatment.

Predictors of Satisfactory Surgical Outcome in Idiopathic Normal Pressure Hydrocephalus (Review)

Idiopathic normal pressure hydrocephalus is a widespread neurodegenerative disease of the elderly. If not treated surgically early, it results in a severe decrease in quality of life and disability. According to current clinical Russian and foreign guidelines the candidates for CSF shunting procedures are selected based on the results of invasive tests, though treatment outcomes are not always optimal. At the same time, in the last decade there have been published a number of studies on promising noninvasive diagnosis and prognosis of the surgical treatment of idiopathic normal pressure hydrocephalus based on neuroimaging findings. The aim of the present systematic review is to demonstrate the most promising imaging predictors of satisfactory outcomes of CSF shunting procedures in patients with idiopathic normal pressure hydrocephalus based on published literature data.

Longitudinal neuropsychological trajectories in idiopathic normal pressure hydrocephalus: a population-based study

BACKGROUND

Idiopathic normal pressure hydrocephalus (iNPH) is a progressive syndrome affecting gait, incontinence, and cognition in a significant number of older adults. Still, prospective studies on early development of symptoms are scarce.

AIM

To investigate how neuropsychological functions develop before and in already diagnosed iNPH over a two-year period in a population-based material.

METHOD

A sample of 104 participants (median [IQR] 75 [72-80] years old) from the general population underwent CT-imaging and clinical assessment at baseline and follow-up. We used the iNPH symptom scale covering four domains (Neuropsychology, Gait, Balance, Incontinence) and additional tests of executive functions. Morphological signs were rated with the iNPH Radscale. Non-parametric statistics with Bonferroni corrections and a significance-level of p < 0.05 were used.

RESULTS

Median (IQR) time to follow-up was 25 (23-26) months. Effect size (ES) for individuals who developed iNPH (n = 8) showed a large (ES r = -0.55) decline in the Gait domain and on the Radscale (ES r = -0.60), with a medium deterioration in declarative memory (ES r = -0.37). Those having iNPH at baseline (n = 12) performed worse on one executive sub-function i.e., shifting (p = 0.045).

CONCLUSION

Besides deterioration in gait and radiology, our results suggest that a neuropsychological trajectory for those developing iNPH includes a reduction in declarative memory. Executive dysfunction was limited to those already having iNPH at baseline. These findings could suggest that memory impairments are included in the early development of iNPH.

Idiopathic normal pressure hydrocephalus: postoperative patient perspective and quality of life

BACKGROUND

Idiopathic normal pressure hydrocephalus (iNPH) is a potentially reversible disease. Surgical results have been well described in the literature, but only a few studies investigated the subjective outcome. This study aimed to investigate the patient's expectations about surgery, the perceived improvement after treatment, and its impact on the quality of life (QoL).

METHODS

A new dedicated survey was created to investigate subjectively different aspects of the treatment pathway of iNPH (diagnosis, symptoms, expectations from surgery, surgical operation, surgical results, and postoperative QoL), together with the SF-12 and EQ-5D as validated, standardized tools.

RESULTS

Forty-five patients were included. Forty-three percent of cases received the diagnosis after at least 1 year, with symptoms worsening in 73%, and frustration in 93%. Reaching a diagnosis was important for 100% of patients, with high expectations from surgery; 86% of them hoped to return to a normal life. Seventy-two percent of patients reported a significant postoperative improvement (walking 68%, mood 57%). Memory and incontinence did not improve in 64% of cases. Subjectively, QoL improved in 72% of cases. The SF-12 score is comparable to controls >75 years, but lower than the 65-75 years group. The EQ-5D index was 0.66 (lower than those of the 65-75 years group = 0.823, and >75 years group = 0.724). Pain and discomfort, instead, were lower compared to the healthy population (43% vs 56%). The idea of having an implanted device and of long-term follow-up is not worrying for 80% of patients; approximately two-thirds of them reported a regained control of their lives.

CONCLUSIONS

The importance of early diagnosis and patients' perspective, alongside clinical evaluation, is highlighted. The self-reported evaluations on symptoms and QoL, along with the balance between postoperative worries and benefits, should be discussed preoperatively with patients and relatives, and included postoperatively to comprehensively assess the surgical outcome.