IMST for Dementia Risk Reduction

This is a 2-arm randomized pilot trial (N=30), including adults aged 60-80 years of age with cardiovascular risks for dementia. Participants will complete assessments prior to beginning the study, each week during the intervention, and at the conclusion of the 8-week intervention. Participants in the experimental group will complete daily high-resistance IMST training (e.g., 75% maximal inspiratory pressure), and participants in the sham condition will complete IMST training at 15% maximal inspiratory pressure. Investigators hypothesize the following: Hypothesis 1: Participants in the high-resistance IMST group will show greater reductions in systolic blood pressure and other vascular health indicators compared to those in the sham IMST group after 8 weeks.

Hypothesis 2: Participants in the high-resistance IMST group will demonstrate greater improvements in executive cognitive function than those in the sham group.

Hypothesis 3: IMST will lead to secondary improvements in mood (reduced depression and anxiety symptoms), better sleep quality (as measured by self-report and actigraphy), and improved physical function (e.g., grip strength, gait speed).

Hypothesis 4: The IMST protocol will be feasible and acceptable, with at least 80% adherence to prescribed training sessions over the 8-week period.

Inclusion criteria

• Ages 60-80
• Converted telephone MoCA total score≥18
• Presence of at least one dementia risk factor (e.g., MCI or subjective cognitive decline, hypertension [SBP >130 mmHg or on medication], sedentary lifestyle [<150 min/week], family history of dementia or self-reported APOE ε4 carrier, or mild sleep-disordered breathing; CAIDE total score [>5]
• Capable of independently completing or requiring minimal assistance with inspiratory muscle strength training (IMST)
• Willing to adhere to the IMST protocol (approximately 5-10 minutes per day for 8 weeks)
• Optional inclusion of inspiratory muscle weakness (MIP <80 cmH₂O for men, <70 cmH₂O for women) will also be assessed.

Exclusion criteria

• tMoCA <18, or diagnosis of neurodegenerative illness at the discretion of principal investigator (except MCI)
• Current evidence of any major psychiatric disorder including psychosis (at the discretion of principal investigator), bipolar disorder, severe major depression (PHQ-9 > 20)
• Unstable cardiovascular or pulmonary disease
• Recent respiratory therapy or major medication changes
• Self-reported severe untreated or unstable obstructive sleep apnea (OSA)
• Recent start (within the past month) of CPAP or BiPAP, or recent use of inspiratory muscle training
• Lung and eardrum injuries
• Non-English speaking
• Participants with a pacemaker or other medical implants containing magnets or electronics will be noted and excluded from body composition analyses.