Symptoms of Depression are Common in Patients With Idiopathic Normal Pressure Hydrocephalus: The INPH-CRasH Study

If patients with idiopathic normal pressure hydrocephalus (INPH) also have depression, this could have important clinical ramifications in assessment and management of their cognitive function and response to shunting. In many dementias, depression is overrepresented, but the prevalence of depression in shunted patients with INPH is unknown.

The objective of this case-control study was to assess the prevalence of symptoms of depression in shunted INPH patients compared with population-based controls.

INPH patients consecutively shunted from 2008 to 2010 in Sweden were analyzed. Patients remaining after inclusion (within 60-85 years and not having dementia, ie, mini-mental state examination ≥23) had a standardized visit to their healthcare provider and answered an extensive questionnaire. Age- and sex-matched population-based controls underwent the same procedure. Symptoms of depression were assessed using the Geriatric Depression Scale 15 (suspected depression defined as ≥5 points, suspected severe depression as ≥12 points). This study is part of the INPH-CRasH study.

One hundred seventy-six INPH patients and 368 controls participated. After adjustment for age, sex, cerebrovascular disease, and systolic and diastolic blood pressure, patients had a higher mean depression score (patients: 4.9 ± 3.7 SD, controls: 1.9 ± 2.3 SD; OR 1.4, 95% CI 1.3-1.6, P < .001), more patients had suspected depression (46% vs 13%, OR 6.4, 95% CI 3.8-10.9, P < .001), and more patients had suspected severe depression (7.3% vs 0.6%, OR 14.4, 95% CI 3.0-68.6, P < .005).

Symptoms of depression are overrepresented in INPH patients compared with the population, despite treatment with a shunt. Screening for depression should be done in the evaluation of INPH patients in order to find and treat a coexisting depression.