Effects on the Olfactory Epithelium and the Olfactory Nerve From Exposure to Diesel Exhaust

Umeå University40 enrolled

Overview

The goal of this study is to study the effect exposure to air pollution and its effect on development of dementia. Does the diesel exhaust change the function of the olfactory system? Have the exposures measurable effects on the sense of smell and cognitive ability? Forty people are exposed to diesel exhaust exhaust and filtered air. The exposures are blinded and in a randomized order. Both groups undergo biopsies of the olfactory epithelium in the nose under local anesthesia after the exposures and after performing cognitive test.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

DIAGNOSTIC

Masking

QUADRUPLE

Enrollment

Conditions

Alzheimer Disease (AD)Dementia Alzheimer Type Air Pollution Exposure

Interventions

During exposure to diesel exhaust, participants alternate between 15-minute periods of rest and exercise on an ergometer cycle with a workload that results in a minute ventilation of 20L/min/m² body surface area. Symptom recording is done every 30 minutes, following a routine based on a modified Borg scale.

Filtered airOTHER

During exposure to filtered air, participants alternate between 15-minute periods of rest and exercise on an ergometer cycle with a workload that results in a minute ventilation of 20L/min/m² body surface area. Symptom recording is done every 30 minutes, following a routine based on a modified Borg scale

Eligibility

Sex: ALLMin age: 20 YearsMax age: 70 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: * Healthy * non-smoker Exclusion Criteria: * Allergic rhinitis * Asthma * Diabetes mellitus * Kidney or liver failure * Angina pectoris or previous ventricular arrhythmia * Systolic blood pressure \>190 mmHg or \<100 mmHg * Previous blood disease * Blood donation in the last three months prior to study start * Previous or ongoing tobacco smoking and exposure to air pollution in the workplace * Absence of informed consent

Outcomes

Primary Outcomes

Diesel exhaust causes cellular dysfunction of the olfactory system

RNA sequencing and DNA methylation will be conducted to identify biomarkers for acute exposure to diesel exhaust.

Time frame: 3 years.

Secondary Outcomes

Cognitive test

Olfactory function well be evaluated by using "sniffin' sticks," and a Letter-Digit Substitution Test as a marker for cognitive processing speed.

Time frame: 3 years