Air purifiers may tame blood sugar spikes in prediabetes

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Participant is ≥18 years old * Participant and members of household are reported to be non-smokers (defined as no household members are currently known to smoke cigarettes or use other tobacco products including e-cigarettes) * Participant is to understand/speak English or Spanish * Participant can understand study procedures and give informed consent * Participant has prediabetes, defined as the absence of diabetes and any of the following: fasting plasma glucose 100-125 mg/dL, 2 hour plasma glucose of 140-199 mg/dL after 75 g oral glucose tolerance test, or A1c 5.7- 6.4%. * Able to wear CGM for 2 two-week periods * Able to participate in telephone or video conference for home equipment setup if needed * Able to visit clinic for blood draws before and after the study period * Do not intend to sleep anywhere outside of primary bedroom for more than 48 consecutive hours or a total of 7 days during the study period. * Ability to lift, or access to assistance with lifting, 20 lb to set up air filter appliance in bedroom. * Have not undergone major dietary change (such as change from usual diet to intermittent fasting or caloric restriction) in the past 2 weeks, and do not intend to during the study period Exclusion Criteria: * Participants who have diagnosed diabetes, or take antihyperglycemic medications * Participants with known atherosclerotic disease: coronary artery disease, peripheral artery disease or history of cerebrovascular disease (stroke or Transient Ischemic Attack (TIA), carotid stenosis) * Participants with known systemic inflammatory conditions (including but not limited to: inflammatory arthritis, vasculitides, inflammatory bowel diseases, cancer within past 5 years, Hashimoto's thyroiditis) * Participants currently taking any anti-inflammatory medications or medications that target inflammatory cytokines * Pregnancy: because blood glucose problems during pregnancy require intensive monitoring and lifestyle changes to protect the mother and fetus * Participants with known or suspected Covid-19 in the prior 30 days * Participants with post-covid sequelae (a.k.a "Long covid") * Participants who are already utilizing HEPA filtration (PAC or within HVAC) in bedrooms