Risk factors, comorbidities, quality of life, and complications after surgery in idiopathic normal pressure hydrocephalus: review of the INPH-CRasH study

Neurosurg Focus 49 (4):E8, 2020

Idiopathic normal pressure hydrocephalus (INPH) is a dementia treatable by insertion of a shunt that drains CSF. The cause of the disease is unknown, but a vascular pathway has been suggested. The INPH-CRasH (Comorbidities and Risk Factors Associated with Hydrocephalus) study was a modern epidemiological case-control study designed to prospectively assess parameters regarding comorbidities and vascular risk factors (VRFs) for INPH, quality of life (QOL), and adverse events in patients with shunted INPH. The objective of this review was to summarize the findings of the INPH-CRasH study.

METHODS VRFs, comorbidities, QOL, and adverse events were analyzed in consecutive patients with INPH who underwent shunt placement between 2008 and 2010 in 5 of 6 neurosurgical centers in Sweden. Patients (n = 176, within the age span of 60–85 years and not having dementia) were compared to population-based age- and gender-matched controls (n = 368, same inclusion criteria as for the patients with INPH). Assessed parameters were as follows: hypertension; diabetes; obesity; hyperlipidemia; psychosocial factors (stress and depression); smoking status; alcohol intake; physical activity; dietary pattern; cerebrovascular, cardiovascular, or peripheral vascular disease; epilepsy; abdominal pain; headache; and clinical parameters before and after surgery. Parameters were assessed through questionnaires, clinical examinations, measurements, ECG studies, and blood samples.

RESULTS Four VRFs were independently associated with INPH: hyperlipidemia, diabetes, obesity, and psychosocial factors. Physical inactivity and hypertension were also associated with INPH, although not independently from the other risk factors. The population attributable risk percent for a model containing all of the VRFs associated with INPH was 24%. Depression was overrepresented in patients with INPH treated with shunts compared to the controls (46% vs 13%, p < 0.001) and the main predictor for low QOL was a coexisting depression (p < 0.001). Shunting improved QOL on a long-term basis. Epilepsy, headache, and abdominal pain remained common for a mean follow-up time of 21 months in INPH patients who received shunts.

CONCLUSIONS The results of the INPH-CRasH study are consistent with a vascular pathophysiological component of INPH. In clinical care and research, a complete risk factor analysis as well as screening for depression and a measurement for QOL should probably be included in the workup of patients with INPH. The effect of targeted interventions against modifiable VRFs and antidepressant treatment in INPH patients should be evaluated. Seizures, headache, and abdominal pain should be inquired about at postoperative follow-up examinations.

Complications in awake versus asleep DBS

J Neurosurg 127:360–369, 2017

As the number of deep brain stimulation (DBS) procedures performed under general anesthesia (“asleep” DBS) increases, it is more important to assess the rates of adverse events, inpatient lengths of stay (LOS), and 30-day readmission rates in patients undergoing these procedures compared with those in patients undergoing traditional “awake” DBS without general anesthesia.

METHODS All patients in an institutional database who had undergone awake or asleep DBS procedures performed by a single surgeon between August 2011 and August 2014 were reviewed. Adverse events, inpatient LOS, and 30-day readmissions were analyzed.

RESULTS A total of 490 electrodes were placed in 284 patients, of whom 126 (44.4%) underwent awake surgery and 158 (55.6%) underwent asleep surgery. The most frequent overall complication for the cohort was postoperative mental status change (13 patients [4.6%]), followed by hemorrhage (4 patients [1.4%]), seizure (4 patients [1.4%]), and hardwarerelated infection (3 patients [1.1%]). Mean LOS for all 284 patients was 1.19 ± 1.29 days (awake: 1.06 ± 0.46 days; asleep: 1.30 ± 1.67 days; p = 0.08). Overall, the 30-day readmission rate was 1.4% (1 awake patient, 3 asleep patients). There were no significant differences in complications, LOS, and 30-day readmissions between awake and asleep groups.

CONCLUSIONS Both awake and asleep DBS can be performed safely with low complication rates. The authors found no significant differences between the 2 procedure groups in adverse events, inpatient LOS, and 30-day readmission rates.

Adverse Events Associated With Deep Brain Stimulation for Movement Disorders: Analysis of 510 Consecutive Cases

DBS 2 leads metal head holder

Operative Neurosurgery 11:190–199, 2015

Although numerous studies have focused on the efficacy of deep brain stimulation (DBS) for movement disorders, less is known about surgical adverse events, especially over longer time intervals.

OBJECTIVE: Here, we analyze adverse events in 510 consecutive cases from a tertiary movement disorders center at up to 10 years postoperatively.

METHODS: We conducted a retrospective review of adverse events from craniotomies between January 2003 and March 2013. The adverse events were categorized into 2 broad categories—immediate perioperative and time-dependent postoperative events.

RESULTS: Across all targets, perioperative mental status change occurred in 18 (3.5%) cases, and symptomatic intracranial hemorrhage occurred in 4 (0.78%) cases. The most common hardware-related event was skin erosion in 13 (2.5%) cases. The most frequent stimulation-related event was speech disturbance in 16 (3.1%) cases. There were no significant differences among surgical targets with respect to the incidence of these events. Time-dependent postoperative events leading to the revision of a given DBS electrode for any reason occurred in 4.7% 6 1.0%, 9.3% 6 1.4%, and 12.4% 6 1.5% of electrodes at 1, 4, and 7 years postoperatively, respectively. Staged bilateral DBS was associated with approximately twice the risk of repeat surgery for electrode replacement vs unilateral surgery (P = .020).

CONCLUSION: These data provide low incidences for adverse events in a large series of DBS surgeries for movement disorders at up to 10 years follow-up. Accurate estimates of adverse events will better inform patients and caregivers about the potential risks and benefits of surgery and provide normative data for process improvement.