Cerebrospinal fluid pressure decreases with older age

Clinical studies implicate low cerebrospinal fluid pressure (CSFP) or a high translaminar pressure difference in the pathogenesis of primary open angle glaucoma (POAG) and normal tension glaucoma (NTG). This study was performed to examine the effect of age, sex, race and body mass index (BMI) on CSFP.

Electronic medical records from all patients who had a lumbar puncture (LP) performed at the Mayo Clinic from 1996-2009 were reviewed. Information including age, sex, race, height and weight, ocular and medical diagnoses, intraocular pressure (IOP) and LP opening pressure was obtained. Patients using medications or with medical diagnoses known to affect CSFP, and those who underwent neurosurgical procedures or where more than one LP was performed were excluded from analysis.

Electronic medical records of 33,922 patients with a history of having an LP during a 13-year period (1996-2009) were extracted. Of these, 12,118 patients met all entry criteria. Relative to mean CSFP at age group 20-49 (mean 11.5±2.8 mmHg), mean CSFP declined steadily after age 50, with percent reduction of 2.5% for the 50-54 age group (mean 11.2±2.7 mmHg, p<0.002) to 26.9% for the 90-95 group (mean 8.4±2.4 mmHg, p<0.001). Females had lower CSFP than males throughout all age groups. BMI was positively and independently associated with CSFP within all age groups.

There is a sustained and significant reduction of CSFP with age that begins in the 6(th) decade. CSFP is consistently lower in females. BMI is positively and independently associated with CSFP in all age groups. The age where CSFP begins to decline coincides with the age where the prevalence of POAG increases. These data support the hypothesis that reduced CSFP may be a risk factor for POAG and may provide an explanation for the mechanism that underlies the age-related increase in the prevalence of POAG and NTG.