Longitudinal post-shunt outcomes in idiopathic normal pressure hydrocephalus with and without comorbid Alzheimer's disease

OBJECTIVE

Alzheimer's disease (AD) is highly comorbid with idiopathic normal pressure hydrocephalus (iNPH) and may diminish the benefits of shunting; however, findings in this area are mixed. We examined postoperative outcomes, with emphases on cognition and utilization of novel scoring procedures to enhance sensitivity.

METHODS

Using participant data from an iNPH outcome study at Butler Hospital, a mixed effect model examined main and interaction effects of time since surgery (baseline, 3 months, 12 months, and 24-60 months) and AD comorbidity (20 iNPH and 11 iNPH+AD) on activities of daily living (ADLs) and iNPH symptoms. Regression modeling explored whether baseline variables predicted improvements 3 months postoperatively.

RESULTS

There were no group differences in gait, incontinence, and global cognition over time, and neither group showed changes in ADLs. Cognitive differences were observed postoperatively; iNPH patients showed stable improvements in working memory (p = 0.012) and response inhibition (p = 0.010), while iNPH + AD patients failed to maintain initial gains. Regarding predicting postoperative outcomes, baseline AD biomarkers did not predict shunt response at 3 months; however, older age at surgery predicted poorer cognitive outcomes (p = 0.04), and presurgical Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) (p = 0.035) and Mini-Mental Status Examination (MMSE) scores (p = 0.009) predicted improvements incontinence.

CONCLUSION

iNPH + AD may be linked with greater declines in aspects of executive functioning postoperatively relative to iNPH alone. While baseline AD pathology may not prognosticate shunt response, younger age appears linked with postsurgical cognitive improvement, and utilizing both brief and comprehensive cognitive measures may help predict improved incontinence. These results illustrate the potential benefits of surgery and inform postoperative expectations for those with iNPH + AD.

Abstract TP156: NIH Stroke Scale at Discharge as a Predictor for Return to Work Status After Mild Stroke

Background: A significant proportion of patients are unable to return to work (RTW) post stroke. While post-stroke depression and fatigue have been linked to patients’ RTW status, the role of discharge NIHSS has not been studied.

Objective: To evaluate role of stroke severity, depression, fatigue, and cognitive impairment on patients’ ability to RTW.

Methods: A retrospective study was conducted using a survey completed by a convenience sample of patients during follow-up in stroke clinic. The survey included PHQ-9, Fatigue Assessment Scale (FAS), and the Montreal Cognitive Assessment (MoCA). Demographic, work status, and clinical data (discharge NIHSS, mRS, medical history) were also collected. NIHSS was evaluated both continuously and dichotomized ( < 1, > 1). Patients who did and did not RTW were compared using chi square tests of proportions and Wilcox Ranked Sum tests; independence of factors was explored using logistic regression predicting RTW.

Results: Out of 135 patients surveyed, 41% (N=56) reported employment at the time of their stroke. Of those, a significant percentage of patients were unable to RTW post stroke (57.1%); 39.3% (N=22) were unable to RTW due to physical limitations. Further analysis revealed patients who did not RTW were more likely to suffer from fatigue (p=0.026), have higher rates of cognitive impairment (p=0.027) and a higher NIHSS at discharge (p<0.001). Very low NIHSS was a very strong RTW predictor as patients with an NIHSS ≤ 1 at discharge were 15 times more likely to RTW than patients with a higher NIHSS (p=.001). Patients who worked in professional, managerial, or artistic occupations pre-stroke were more likely to return to work than those in public service, skilled or unskilled labor occupations (p=0.023). In multivariate analyses, fatigue, cognitive impairment and depression were no longer significant when NIHSS at discharge was a covariate. Type of occupation was independent of NIHSS.

Conclusions: For patients with mild stroke, NIHSS at discharge indicating minimal to no disability is a strong independent predictor for RTW status. For patients with greater deficit, depression, fatigue and cognitive impairment could play a greater role; additional studies of patients with greater variety of stroke severity would be needed.

Abstract TP161: Sexual Dysfunction in Mild Stroke

Background: Stroke impacts several aspects of patients’ lives and sexual dysfunction post stroke has been reported in 40%-50% of patients. Current investigations have revealed links to depression, however this has not been examined specifically in mild stroke.

Objective: To determine prevalence and factors associated with sexual dysfunction after mild stroke

Design/methods: A retrospective study was conducted on a self-report questionnaire completed by a convenience sample of patients during a hospital follow-up appointment in the stroke clinic. Patients were asked about sexual dysfunction after stroke and if yes, to specify the cause: safety concern, physical limitation, consequence or change in libido. In addition, patients completed a PHQ-9 to measure depression, Fatigue Assessment Scale (FAS), and the Montreal Cognitive Assessment (MoCA). A thorough review of clinical history including NIHSS, mRS and demographics was completed by researchers. Descriptive statistics were used to identify and understand the patient population. Mild stroke was defined as NIHSS ≤ 5.

Results: In our study of 135 patients, 21 (16%) did not respond to the sexual dysfunction question. Of the 114 who responded, only 11 (9.6%) reported sexual dysfunction and 9 (81%) attributed their sexual dysfunction to physical limitations. Descriptive statistics of the respondent subgroup indicate that the cohort was 59% male with a median (IQR) age of 64 (57,75) and that 52% were living with someone at the time. The mean NIHSS on discharge was 1 (IQR 0-3) and 77% were ischemic strokes. Few patients experienced post stroke depression (21.9%, N=25), and the cohort reported low levels of fatigue (median FAS=19). Low incidence and response rates precluded an analysis of specific predictors in this cohort.

Conclusion: Physical limitations are reported to be the main cause of post stroke sexual dysfunction. Roughly 1 in 10 patients with mild stroke reported experiencing sexual dysfunction, however twice as many did not respond to the question. Therefore, the true incidence is unclear, prompting the need for further investigation on post stroke sexual dysfunction in mild stroke.