Health‐related quality‐of‐life outcome in patients with idiopathic normal‐pressure hydrocephalus – a 1‐year follow‐up study

Background and purpose This prospective study explored the factors affecting the health‐related quality‐of‐life (HRQoL) outcome in patients with idiopathic normal‐pressure hydrocephalus (iNPH) 1 year after the installation of the cerebrospinal fluid shunt. Methods The HRQoL outcome was evaluated using a 15D instrument, in which the minimum clinically significant change/difference has been estimated to be ±0.015. The follow‐up data (15D, Mini‐Mental State Examination, Beck Depression Inventory, iNPH Grading Scale), frontal cortical biopsy, Charlson Age Comorbidity Index and body mass index of 145 patients diagnosed with iNPH by clinical and radiological examination were analyzed. Results At 1‐year follow‐up, 63 (43%) patients had experienced a clinically significant improvement in HRQoL. Multivariate binary logistic regression analysis indicated that the absence of amyloid‐β and hyperphosphorylated tau pathology in the frontal cortical biopsy (53% vs. 33%; absolute risk difference, 20%; adjusted odds ratio, 2.27; 95% confidence interval, 1.07–4.84; P < 0.05) and lower body mass index (adjusted odds ratio, 0.90, 95% confidence interval, 0.82–0.98; P < 0.05) predicted favorable HRQoL outcome 1 year after the shunting. Conclusions Less than half of the patients with iNPH experienced clinically significant favorable HRQoL outcome, partly explained by the patient's characteristics and comorbidities. The HRQoL approach reveals aspects that are important for the patient's well‐being, but may also improve the quality of the outcome assessment of cerebrospinal fluid shunting. Study results may help clinicians to estimate which patients will benefit shunt surgery.